OnApplyTemplate is not being called - silverlight

I have a solution with 2 projects: Windows Phone App and a Windows Phone Class Library. The class library has a control called MessageBoxExtended which inherits from ContentControl. The project also has a Themes folder with a generic.xaml file. The file has the Build Action set to Page and it looks like this:
<ResourceDictionary
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:KontactU.Common.WPControls;assembly=KontactU.Common.WPControls"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">
<Style TargetType="local:MessageBoxExtended">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="local:MessageBoxExtended">
<Grid x:Name="LayoutRoot">
<StackPanel>
<TextBlock x:Name="lblTitle" Text="Title Goes Here" Style="{StaticResource PhoneTextTitle3Style}"/>
<TextBlock x:Name="lblMessage" Text="Some long message here repeated over and over again. Some long message here repeated over and over again. " TextWrapping="Wrap" Style="{StaticResource PhoneTextNormalStyle}" />
<StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
<Button x:Name="btnLeft" Content="Button1" Click="btnLeft_Click"></Button>
<Button x:Name="btnCenter" Content="Button2" Click="btnCenter_Click"></Button>
<Button x:Name="btnRight" Content="Button3" Click="btnRight_Click"></Button>
</StackPanel>
</StackPanel>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
The control code looks like this:
public class MessageBoxExtended : ContentControl
{
private TextBlock lblTitle;
private TextBlock lblMessage;
private Button btnLeft;
private Button btnCenter;
private Button btnRight;
private bool currentSystemTrayState;
internal Popup ChildWindowPopup
{
get;
private set;
}
private static PhoneApplicationFrame RootVisual
{
get
{
return Application.Current == null ? null : Application.Current.RootVisual as PhoneApplicationFrame;
}
}
public MessageBoxExtended()
: base()
{
DefaultStyleKey = typeof(MessageBoxExtended);
}
public override void OnApplyTemplate()
{
base.OnApplyTemplate();
lblTitle = this.GetTemplateChild("lblTitle") as TextBlock;
lblMessage = this.GetTemplateChild("lblMessage") as TextBlock;
btnLeft = this.GetTemplateChild("btnLeft") as Button;
btnCenter = this.GetTemplateChild("btnCenter") as Button;
btnRight = this.GetTemplateChild("btnRight") as Button;
InitializeMessageBoxExtended("Title", "Message", MessageBoxExtendedButtonType.Ok);
}
private void InitializeMessageBoxExtended(string title, string message, MessageBoxExtendedButtonType buttonType)
{
HideSystemTray();
lblTitle.Text = title;
lblMessage.Text = message;
switch (buttonType)
{
case MessageBoxExtendedButtonType.Ok:
btnLeft.Visibility = System.Windows.Visibility.Collapsed;
btnRight.Visibility = System.Windows.Visibility.Collapsed;
btnCenter.Content = "ok";
break;
case MessageBoxExtendedButtonType.OkCancel:
btnCenter.Visibility = System.Windows.Visibility.Collapsed;
btnLeft.Content = "ok";
btnRight.Content = "cancel";
break;
case MessageBoxExtendedButtonType.YesNo:
btnCenter.Visibility = System.Windows.Visibility.Collapsed;
btnLeft.Content = "yes";
btnRight.Content = "no";
break;
}
}
public void Show(string title, string message, MessageBoxExtendedButtonType buttonType)
{
if (ChildWindowPopup == null)
{
ChildWindowPopup = new Popup();
try
{
ChildWindowPopup.Child = this;
}
catch (ArgumentException)
{
throw new InvalidOperationException("The control is already shown.");
}
}
if (ChildWindowPopup != null && Application.Current.RootVisual != null)
{
// Configure accordingly to the type
InitializeMessageBoxExtended(title, message, buttonType);
// Show popup
ChildWindowPopup.IsOpen = true;
}
}
private void HideSystemTray()
{
// Capture current state of the system tray
this.currentSystemTrayState = SystemTray.IsVisible;
// Hide it
SystemTray.IsVisible = false;
}
}
The Windows Phone App references it and calls it in the code behind by instantiating it and calling the Show method:
MessageBoxExtended mbe = new MessageBoxExtended();
mbe.Show();
The problem is that the OnApplyTemplate is never called. I've tried commenting out all the lines in the generic.xaml, but I get the same result.
Any ideas?

Never mind, it was my mistake. I added
if (lblTitle == null)
return;
to the InitializeMessageBoxExtended() method and now it works. If you follow the logic the constructor is called before the OnApplyTemplate() which calls the InitializeMessageBoxExtended() and therefore the values are null. By adding the code above the control doesn't throw an exception, it continues and when the control is part of the VisualTree the OnApplyTemplate is called.
Hope this helps anyone out there.

Related

Custom WPF MessageBox does not return MessageBoxResult

This is the xaml "SidiMessageBoxWindow.xaml" file:
<Window
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008" mc:Ignorable="d">
<Border>
<Grid x:Name="mainGrid" Margin="0">
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<ScrollViewer Grid.Row="0" VerticalScrollBarVisibility="Auto" Margin="0">
<TextBlock x:Name="TextBlock" TextWrapping="Wrap" Text="TextBlock" ScrollViewer.VerticalScrollBarVisibility="Auto" Height="Auto"/>
</ScrollViewer>
<Grid Grid.Row="1" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Height="Auto" Width="Auto" Margin="0,10,0,0">
<Button x:Name="btnCancel" Content="Cancel" Width="Auto" MinWidth="0" Height="30"
HorizontalAlignment="Right" HorizontalContentAlignment="Center" VerticalAlignment="Center" VerticalContentAlignment="Center"
Margin="0,0,45,0" Padding="4,0,4,0" BorderThickness="1" />
<Button x:Name="btnOk" Content="Ok" Width="Auto" MinWidth="40" Height=" 30"
HorizontalAlignment="Right" HorizontalContentAlignment="Center" VerticalAlignment="Center" VerticalContentAlignment="Center"
Margin="0" Padding="4,0,4,0" BorderThickness="1" />
</Grid>
</Grid>
</Border>
and here the "SidiMessageBox1" class
I can't use "messageBox.ShowDialog();" here because I have to use the class "NTWindow" which I don't have access to.
public class SidiMessageBox1 : SidiMessageBoxWindow1
{
public static MessageBoxResult Show(ChartControl chartControl, string text, MessageBoxButton buttons = MessageBoxButton.OK)
{
if (chartControl == null)
{
return MessageBoxResult.None;
}
var messageBox = CreateMessageBox(chartControl, text, buttons);
messageBox.Show();
return messageBox.MsgBoxResult;
}
private static SidiMessageBoxWindow1 CreateMessageBox(ChartControl chartControl, string text, MessageBoxButton buttons)
{
return new SidiMessageBoxWindow1(text, buttons)
{
Owner = chartControl.OwnerChart,
Foreground = Application.Current.TryFindResource("FontControlBrush") as SolidColorBrush
};
}
}
and here is the SidiMessageBoxWindow1 class
public class SidiMessageBoxWindow1 : NTWindow
{
private static readonly string xamlFilePath = Path.Combine(Globals.UserDataDir, #"bin\Custom\AddOns\Sidi\SidiMessageBoxWindow.xaml");
private string text;
private Button btnOk, btnCancel;
private TextBlock textBlock;
private MessageBoxButton buttons;
public SidiMessageBoxWindow1()
{
}
public SidiMessageBoxWindow1(string text, MessageBoxButton buttons)
{
this.text = text;
Caption = "SidiMessageBox";
Topmost = true;
MinHeight = 100;
MinWidth = 200;
ResizeMode = ResizeMode.NoResize;
SizeToContent = SizeToContent.WidthAndHeight;
WindowStartupLocation = WindowStartupLocation.CenterOwner;
Content = LoadXaml(xamlFilePath);
Buttons = buttons;
}
private void OkButton_Click(object sender, RoutedEventArgs e)
{
btnOk.Click -= OkButton_Click;
Close();
}
private void CancelButton_Click(object sender, RoutedEventArgs e)
{
btnCancel.Click -= CancelButton_Click;
Close();
}
private DependencyObject LoadXaml(string xmlFilePath)
{
Window page;
FileStream fs = new FileStream(xmlFilePath, FileMode.Open);
page = (Window)XamlReader.Load(fs);
btnOk = LogicalTreeHelper.FindLogicalNode(page, "btnOk") as Button;
btnCancel = LogicalTreeHelper.FindLogicalNode(page, "btnCancel") as Button;
textBlock = LogicalTreeHelper.FindLogicalNode(page, "TextBlock") as TextBlock;
textBlock.Text = text;
return page.Content as DependencyObject;
}
public MessageBoxButton Buttons
{
get
{
return buttons;
}
set
{
buttons = value;
btnCancel.Visibility = Visibility.Collapsed;
btnOk.Visibility = Visibility.Collapsed;
switch (buttons)
{
case MessageBoxButton.OK:
btnOk.Visibility = Visibility.Visible;
btnOk.Click += OkButton_Click;
break;
case MessageBoxButton.OKCancel:
btnCancel.Visibility = Visibility.Visible;
btnOk.Visibility = Visibility.Visible;
btnOk.Click += OkButton_Click;
btnCancel.Click += CancelButton_Click;
break;
}
}
}
public MessageBoxResult MsgBoxResult { get; set; }
}
call:
var result = SidiMessageBox1.Show(ChartControl, "text");
the messageboxwindow looks like this:
everything works fine, as it should, except that I don't get a "MessageBoxResult" back. Unfortunately I don't know how to do that with this code.
I thank "BionicCode" for his explanation and hope for your understanding, because i am still quite a beginner ;-)
To use the Thread class is considered an obsolete programming model. Since the introduction of async and await with .NET Framework 4.5 the recommended programming model is the Microsoft Docs: Task asynchronous programming model.
As the member name Dispatcher.InvokeAsync suggests, this method is awaitable and supports asynchronous execution.
Your code actually does not execute the Window on a new thread. Because you use post related code to the Dispatcher, the Window is shown on the main thread.
Showing another Window will not block the other Window instances.
Additionally, your posted code is quite smelly. You should never block a constructor. But showing a modal dialog from a constructor will block construction. A constructor must initialize the members and return immediately.
Instead you must create and show the Window instance from your static Show method:
public static MessageBoxResult Show(ChartControl chartControl, string text, MessageBoxButton buttons)
{
if (chartControl == null)
{
return MessageBoxResult.None;
}
SidiMessageBoxWindow messageBox = CreateMessageBox(chartControl, text, buttons);
// If just an OK button, allow the user to just move away from the dialog
if (buttons == MessageBoxButton.OK)
{
messageBox.Show();
}
else
{
messageBox.ShowDialog();
}
return messageBox.MsgBoxResult;
}
private static SidiMessageBoxWindow CreateMessageBox(ChartControl chartControl, string text, MessageBoxButton buttons)
{
return new SidiMessageBoxWindow(xamlFilePath, logFilePath, text, buttons, chartControl)
{
Owner = chartControl.OwnerChart,
Foreground = Application.Current.TryFindResource("FontControlBrush") as SolidColorBrush
};
}
private SidiMessageBoxWindow(ChartControl chartControl, string text, MessageBoxButton buttons)
{
this.chartControl = chartControl;
this.text = text;
this.buttons = buttons;
}

Can anyone provide a concrete example of WPF "visual inheritance" for a dialog box?

I am an experienced WinForms developer, relatively new to WPF. I have a large WinForms application that uses a couple different base classes to represent dialog boxes. One such example is AbstractOkCancelDialog. That class contains a panel at the bottom of a dialog, with an Ok and Cancel button on the right side of the panel. I'm trying to determine the best way to handle this, as I realize that WPF doesn't provide visual inheritance.
I don't want to have to create OK and Cancel buttons, and place them, for every dialog in the application.
I have read that the way to do this in WPF is with user controls. I can envision creating a user control with OK and Cancel buttons on it. But I don't want to have to manually place that user control on hundreds of dialogs in my application. I'd really like to have something like this:
public AbstractOkCancelDialog = class(Window)
{
protected AbstractOkCancelDialogViewModel _ViewModel;
// AbstractOkCancelDialogViewModel would have commands for OK and Cancel.
// Every dialog would inherit from AbstractOkCancelDialog, and would use
// a viewmodel that inherits from AbstractOkCancelDialogViewModel. In
// this way, all view models would automatically be connected to the OK
// and Cancel commands.
}
I've seen some discussion online about how to create the base class. Those discussions explain how there can't be a xaml file associated with the dialog base class, and I understand that restriction. I just can't figure out how to automatically place the user control with the OK and Cancel buttons.
I'm hoping that someone can point me to a sample solution that shows this kind of structure. Thank you in advance!
Write one dialog class. It's a subclass of Window. It has XAML:
<Window
...blah blah blah...
Title="{Binding Title}"
>
<StackPanel MinWidth="300">
<!-- This is how you place content within content in WPF -->
<ContentControl
Content="{Binding}"
Margin="2"
/>
<StackPanel Orientation="Horizontal" HorizontalAlignment="Right" Margin="2,20,2,2">
<Button
Margin="2"
MinWidth="60"
DockPanel.Dock="Right"
Content="OK"
Click="OK_Click"
IsDefault="True"
/>
<Button
Margin="2"
MinWidth="60"
DockPanel.Dock="Right"
Content="Cancel"
IsCancel="True"
Click="Cancel_Click"
/>
</StackPanel>
</StackPanel>
</Window>
You can fancy that up endlessly, but this is a decent minimum to give you arbitrary content above a row of right-aligned buttons. Adding more buttons as needed could involve either templating that portion of the window as well, or creating them with an ItemsControl (I've done that in our production code), or a few other options.
Usage:
var vm = new SomeDialogViewModel();
var dlg = new MyDialog { DataContext = vm };
For each dialog viewmodel, consumers must define an implicit datatemplate which provides UI for that viewmodel.
I would suggest writing a dialog viewmodel interface which the consumer is expected to implement.
public interface IDialogViewModel
{
String Title { get; set; }
void OnOK();
// Let them "cancel the cancel" if they like.
bool OnCancel();
}
The window can check if its DataContext implements that interface, and act accordingly. If you like, it could require that interface and throw an exception of it isn't implemented, or it could just talk to it only if it's there. If they don't implement it but they still have a Title property, the binding to Title will still work. Bindings are "duck typed".
Naturally, you can write an OKCancelDialogViewModel or a SelectStringFromListViewModel, write corresponding DataTemplates that implement their UIs, and write nice clean static methods which show them:
public static class Dialogs
{
public static TOption Select<TOption>(IEnumerable<TOption> options, string prompt,
string title = "Select Option") where TOption : class
{
// Viewmodel isn't generic because that breaks implicit datatemplating.
// That's OK because XAML uses duck typing anyhow.
var vm = new SelectOptionDialogViewModel
{
Title = title,
Prompt = prompt,
Options = options
};
if ((bool)new Dialog { DataContext = vm }.ShowDialog())
{
return vm.SelectedOption as TOption;
}
return null;
}
// We have to call the value-type overload by a different name because overloads can't be
// distinguished when the only distinction is a type constraint.
public static TOption? SelectValue<TOption>(IEnumerable<TOption> options, string prompt,
string title = "Select Option") where TOption : struct
{
var vm = new SelectOptionDialogViewModel
{
Title = title,
Prompt = prompt,
// Need to box these explicitly
Options = options.Select(opt => (object)opt)
};
if ((bool)new Dialog { DataContext = vm }.ShowDialog())
{
return (TOption)vm.SelectedOption;
}
return null;
}
}
Here's a viewmodel datatemplate for the above selection dialog:
<Application.Resources>
<DataTemplate DataType="{x:Type local:SelectOptionDialogViewModel}">
<StackPanel>
<TextBlock
TextWrapping="WrapWithOverflow"
Text="{Binding Prompt}"
/>
<ListBox
ItemsSource="{Binding Options}"
SelectedItem="{Binding SelectedOption}"
MouseDoubleClick="ListBox_MouseDoubleClick"
/>
</StackPanel>
</DataTemplate>
</Application.Resources>
App.xaml.cs
private void ListBox_MouseDoubleClick(object sender,
System.Windows.Input.MouseButtonEventArgs e)
{
((sender as FrameworkElement).DataContext as IDialogViewModel).DialogResult = true;
}
var a = Dialogs.Select(new String[] { "Bob", "Fred", "Ginger", "Mary Anne" },
"Select a dance partner:");
var b = Dialogs.SelectValue(Enum.GetValues(typeof(Options)).Cast<Options>(),
"Select an enum value:");
Here an example of how to use a custom AlertDialog
UserControl
<UserControl x:Class="Library.Views.AlertMessageDialogView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:p="clr-namespace:Library.Properties"
DataContext="{Binding RelativeSource={RelativeSource Self}}"
FlowDirection = "{Binding WindowFlowDirection, Mode=TwoWay}">
<Grid Background="{DynamicResource WindowBackgroundBrush}">
<Canvas HorizontalAlignment="Left" Height="145" VerticalAlignment="Top" Width="385">
<Label HorizontalAlignment="Left" Height="57" VerticalAlignment="Top" Width="365" Canvas.Left="10" Canvas.Top="10" FontSize="14" >
<TextBlock x:Name="txtVocabAnglais" TextWrapping="Wrap" Text="{Binding Message, Mode=TwoWay}" Width="365" Height="57" />
</Label>
<Button x:Name="cmdCancel" Content="{x:Static p:Resources.AlertMessageDialogViewcmdCancel}" Height="30" Canvas.Left="163" Canvas.Top="72" Width="71" Command = "{Binding CancelCommand}" CommandParameter = "null" IsDefault="True"/>
</Canvas>
</Grid>
</UserControl>
ViewModel Class
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;
using System.Windows;
using System.ComponentModel;
using System.Windows.Controls;
namespace Library.ViewModel
{
public class AlertMessageDialogViewModel : BindableBaseViewModel
{
public event EventHandler CloseWindowEvent;
private string _title;
private string _message;
public BaseCommand<string> YesCommand { get; private set; }
public BaseCommand<string> CancelCommand { get; private set; }
private WinformsNameSpace.FlowDirection _windowFlowDirection;
public AlertMessageDialogViewModel()
{
CancelCommand = new BaseCommand<string>(cmdCancelBtnClick);
WindowFlowDirection = CustomFuncVar.WindowFlowDirection;
}
public WinformsNameSpace.FlowDirection WindowFlowDirection
{
get
{
return _windowFlowDirection;
}
set
{
_windowFlowDirection = value;
OnPropertyChanged("WindowFlowDirection");
}
}
public string Message
{
get
{
return _message;
}
set
{
_message = value;
OnPropertyChanged("Message");
}
}
public string Title
{
get
{
return _title;
}
set
{
_title = value;
}
}
private void cmdCancelBtnClick(string paramerter)
{
if (CloseWindowEvent != null)
CloseWindowEvent(this, null);
}
}
}
DialogMessage Class
using System;
using System.Windows;
using System.Collections.Generic;
namespace Library.Helpers
{
public static class DialogMessage
{
public static void AlertMessage(string message, string title, Window OwnerWindowView)
{
try
{
//Affichage de méssage de succès enregistrement
AlertMessageDialogViewModel alertDialogVM = new AlertMessageDialogViewModel();
alertDialogVM.Message = message;
alertDialogVM.Title = title;
// Auto Generation Window
FrameworkElement view = LpgetCustomUI.AutoGetViewFromName("AlertMessageDialogView");
view.DataContext = alertDialogVM;
Dictionary<string, object> localVarWindowProperty = new Dictionary<string, object>();
localVarWindowProperty = LpgetCustomUI.GetWindowPropretyType_400x145(Properties.Resources.ApplicationTitle);
CummonUIWindowContainer alertDialogView = new CummonUIWindowContainer(view, null, false, localVarWindowProperty);
//End Auto Generation Window
// Attachement de l'évènement de fermture de View au modèle
alertDialogVM.CloseWindowEvent += new EventHandler(alertDialogView.fnCloseWindowEvent);
if (OwnerWindowView!=null)
{
alertDialogView.Owner = OwnerWindowView;
}
else
{
alertDialogView.WindowStartupLocation = WindowStartupLocation.CenterScreen;
}
alertDialogView.ShowDialog();
}
catch (Exception ex)
{
}
}
}
}
CummonUIWindowContainer Class
namespace CummonUILibrary.CummonUIHelpers
{
public class CummonUIWindowContainer : Window
{
public event RoutedEventHandler CmbRootEvtLanguageChange;
private FrameworkElement currentView;
private ContentControl _contentcontainer;
public CummonUIWindowContainer(string usercontrolName)
{
Contentcontainer = new ContentControl();
currentView = new FrameworkElement();
}
public CummonUIWindowContainer()
{
Contentcontainer = new ContentControl();
currentView = new FrameworkElement();
}
public CummonUIWindowContainer(FrameworkElement view, object model, bool setDataContextToView, Dictionary<string, object> WindowPropertyList)
{
Contentcontainer = new ContentControl();
Contentcontainer.Name = "ContentControl";
SetWindowProperty(view, model, setDataContextToView, WindowPropertyList);
}
public void SetWindowProperty(FrameworkElement view, object model, bool setDataContextToView, Dictionary<string, object> WindowPropertyList)
{
try
{
LinearGradientBrush brush = new LinearGradientBrush();
GradientStop gradientStop1 = new GradientStop();
gradientStop1.Offset = 0;
gradientStop1.Color = Colors.Yellow;
brush.GradientStops.Add(gradientStop1);
GradientStop gradientStop2 = new GradientStop();
gradientStop2.Offset = 0.5;
gradientStop2.Color = Colors.Indigo;
brush.GradientStops.Add(gradientStop2);
GradientStop gradientStop3 = new GradientStop();
gradientStop3.Offset = 1;
gradientStop3.Color = Colors.Yellow;
brush.GradientStops.Add(gradientStop3);
this.Background = brush;
CurrentView = view;
Type elementType = this.GetType();
ICollection<string> WindowPropertyListNames = WindowPropertyList.Keys;
foreach (string propertyName in WindowPropertyListNames)
{
PropertyInfo property = elementType.GetProperty(propertyName);
property.SetValue(this, WindowPropertyList[propertyName]);
}
if (setDataContextToView == true & model != null)
{
CurrentView.DataContext = model;
}
if (CurrentView != null)
{
Contentcontainer.Content = CurrentView;
}
//Contentcontainer.Margin = new Thickness(0,0, 0, 0);
IAddChild container=this;
container.AddChild(Contentcontainer);
}
catch (Exception ex)
{
}
}
public void fnCloseWindowEvent(object sender, EventArgs e)
{
this.Close();
}
public ContentControl Contentcontainer
{
get
{
return _contentcontainer;
}
set
{
_contentcontainer = value;
}
}
public FrameworkElement CurrentView
{
get
{
return currentView;
}
set
{
if (this.currentView != value)
{
currentView = value;
//RaisePropertyChanged("CurrentView");
}
}
}
private void cmbLanguage_SelectionChanged(object sender, RoutedEventArgs e)
{
//CmbRootEvtLanguageChange(sender, e);
}
}
}
How to use the Class
DialogMessage.AlertMessage("My Custom Message", "My Custom Title Message");
Thats how i would do it
Create an abstract base class for your dialog and changing the corresponding ControlTemplate
AbstractOkCancelDialog
public abstract class AbstractOkCancelDialog : Window
{
public static readonly DependencyProperty CancelCommandParameterProperty =
DependencyProperty.Register(
"CancelCommandParameter",
typeof(object),
typeof(AbstractOkCancelDialog),
new FrameworkPropertyMetadata((object) null));
public static readonly DependencyProperty CancelCommandProperty =
DependencyProperty.Register(
"CancelCommand",
typeof(ICommand),
typeof(AbstractOkCancelDialog),
new FrameworkPropertyMetadata((ICommand) null));
public static readonly DependencyProperty OkCommandParameterProperty =
DependencyProperty.Register(
"OkCommandParameter",
typeof(object),
typeof(AbstractOkCancelDialog),
new FrameworkPropertyMetadata((object) null));
public static readonly DependencyProperty OkCommandProperty =
DependencyProperty.Register(
"OkCommand",
typeof(ICommand),
typeof(AbstractOkCancelDialog),
new FrameworkPropertyMetadata((ICommand) null));
static AbstractOkCancelDialog()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(AbstractOkCancelDialog), new
FrameworkPropertyMetadata(typeof(AbstractOkCancelDialog)));
}
public ICommand CancelCommand
{
get => (ICommand) GetValue(CancelCommandProperty);
set => SetValue(CancelCommandProperty, value);
}
public object CancelCommandParameter
{
get => GetValue(CancelCommandParameterProperty);
set => SetValue(CancelCommandParameterProperty, value);
}
public ICommand OkCommand
{
get => (ICommand) GetValue(OkCommandProperty);
set => SetValue(OkCommandProperty, value);
}
public object OkCommandParameter
{
get => GetValue(OkCommandParameterProperty);
set => SetValue(OkCommandParameterProperty, value);
}
}
Style
Put in Generic.xaml[?]
<Style
BasedOn="{StaticResource {x:Type Window}}"
TargetType="{x:Type local:AbstractOkCancelDialog}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type local:AbstractOkCancelDialog}">
<Border
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}">
<AdornerDecorator>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<ContentPresenter />
<Grid Grid.Row="1">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="Auto" />
</Grid.ColumnDefinitions>
<Button
Grid.Column="1"
Margin="5"
Command="{TemplateBinding OkCommand}"
CommandParameter="{TemplateBinding OkCommandParameter}"
Content="Ok"
DockPanel.Dock="Right" />
<Button
Grid.Column="2"
Margin="5"
Command="{TemplateBinding CancelCommand}"
CommandParameter="{TemplateBinding CancelCommandParameter}"
Content="Cancel"
DockPanel.Dock="Right" />
</Grid>
</Grid>
</AdornerDecorator>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
Now you can create your individual dialogs like you would create any other window
Brief example:
TestDialog.xaml
<local:AbstractOkCancelDialog
x:Class="WpfApp.TestDialog"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:WpfApp"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
Title="TestDialog"
Width="800"
Height="450"
OkCommand="{x:Static local:Commands.OkWindowCommand}"
OkCommandParameter="{Binding RelativeSource={RelativeSource Self}}"
CancelCommand="{x:Static local:Commands.CancelWindowCommand}"
CancelCommandParameter="{Binding RelativeSource={RelativeSource Self}}"
mc:Ignorable="d">
<Grid>
<!-- Content -->
</Grid>
</local:AbstractOkCancelDialog>
TestDialog.xaml.cs
public partial class TestDialog : AbstractOkCancelDialog
{
...
}

Template.FindName does not work if I set Name from code

As you can see in code below, I have descendant of ScrollViewer, and set Name of MyScrollView in ctor. But when I try using MyScrollViewer in control template I cannot find one via Template.FindName
If I change <local:MyScrollViewer /> to <local:MyScrollViewer Name=""PART_ContentHost"" /> code works as expected, but I am looking for solution without changing XAML.
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
var parserContext = new ParserContext
{
XamlTypeMapper = new XamlTypeMapper(new string[0]),
XmlnsDictionary =
{
{ "", "http://schemas.microsoft.com/winfx/2006/xaml/presentation" },
{ "x", "http://schemas.microsoft.com/winfx/2006/xaml" },
{ "local", "clr-namespace:" + typeof(MyScrollViewer).Namespace + ";assembly=" + typeof(MyScrollViewer).Assembly.FullName}
}
};
var template = (ControlTemplate)XamlReader.Parse(#"
<ControlTemplate TargetType=""TextBox"">
<Border>
<local:MyScrollViewer />
<!--<local:MyScrollViewer Name=""PART_ContentHost""/> -->
</Border>
</ControlTemplate>
", parserContext);
// Name=""PART_ContentHost""
Content = new MyTextBox { Template = template };
}
}
public class MyScrollViewer: ScrollViewer
{
public MyScrollViewer() => Name = "PART_ContentHost";
}
public class MyTextBox: TextBox
{
public override void OnApplyTemplate()
{
base.OnApplyTemplate();
var contentHost = Template.FindName("PART_ContentHost", this);
if (contentHost == null)
throw new Exception("Can not find PART_ContentHost");
}
}
updated:
Even I put my control template into MainWindow.xaml (and remove from MainWindow ctor), it doesnot work.
public MainWindow()
{
InitializeComponent();
}
<Window x:Class="WpfApp1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:WpfApp1"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<Grid>
<Grid.Resources>
<ControlTemplate TargetType="local:MyTextBox" x:Key="TextBoxTemplate">
<local:MyScrollViewer />
</ControlTemplate>
</Grid.Resources>
<local:MyTextBox Template="{StaticResource TextBoxTemplate}" />
</Grid>
</Window>
The constructor of MyScrollViewer will not be called on template creation with XamlReader, so the names with which MyScrollViewer was created are stored in internal dictionaries. See template.ChildNames. The constructor of MyScrollViewer will first being called, when MyTextBox becomes visible, but it's already too late.
Template being created from XAML and it notices the children names by parsing, without creation of children instances. Later the children instances will be created, but the template hold old names. So if you call Template.FindNames with new names, they will not be found.
Try
var contentHost = Template.FindName("2_T", this);
but I am looking for solution without changing XAML
Setting the name in the constructor of the ScrollViewer won't work. You have to set it in the template for it to be registered in the namescope of the template.
If you don't want to assign the element a Name in the template, you could wait for it to get created and then find it in the visual tree without using a name:
public class MyTextBox : TextBox
{
public MyTextBox()
{
Loaded += MyTextBox_Loaded;
}
private void MyTextBox_Loaded(object sender, RoutedEventArgs e)
{
MyScrollViewer sv = FindVisualChild<MyScrollViewer>(this);
//...
}
private static T FindVisualChild<T>(Visual visual) where T : Visual
{
for (int i = 0; i < VisualTreeHelper.GetChildrenCount(visual); i++)
{
Visual child = (Visual)VisualTreeHelper.GetChild(visual, i);
if (child != null)
{
T correctlyTyped = child as T;
if (correctlyTyped != null)
{
return correctlyTyped;
}
T descendent = FindVisualChild<T>(child);
if (descendent != null)
{
return descendent;
}
}
}
return null;
}
}

Opening a ContextMenu from a button click

I'm trying to create a button that displays content in a popup when it is clicked. So I came up with something simple like this :
public class DropdownButton : Button
{
public object DropdownContent
{
get { return (object)GetValue(DropdownContentProperty); }
set { SetValue(DropdownContentProperty, value); }
}
public static readonly DependencyProperty DropdownContentProperty =
DependencyProperty.Register("DropdownContent", typeof(object), typeof(DropdownButton), new PropertyMetadata(null));
protected override void OnClick()
{
base.OnClick();
if(DropdownContent != null)
{
if(DropdownContent is ContextMenu)
{
ContextMenu = (ContextMenu)DropdownContent;
ContextMenu.IsOpen = true;
}
else
{
// launch a popup
}
}
}
}
and am using it like this :
public partial class MainWindow : Window
{
public string A { get { return "A"; } }
public string B { get { return "B"; } }
public MainWindow()
{
DataContext = this;
InitializeComponent();
}
}
<Window x:Class="WpfApplication45.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:l="clr-namespace:WpfApplication45"
Title="MainWindow"
WindowStartupLocation="CenterScreen">
<Window.Resources>
<ContextMenu x:Key="sharedMenu">
<MenuItem Header="{Binding}" />
</ContextMenu>
</Window.Resources>
<StackPanel>
<UniformGrid Columns="2"
DataContext="{Binding A}">
<TextBlock Text="{Binding}"
Background="#CCC"
ContextMenu="{StaticResource sharedMenu}"/>
<l:DropdownButton DropdownContent="{StaticResource sharedMenu}" />
</UniformGrid>
<UniformGrid Columns="2"
DataContext="{Binding B}">
<TextBlock Text="{Binding}"
Background="#CCC"
ContextMenu="{StaticResource sharedMenu}"/>
<l:DropdownButton DropdownContent="{StaticResource sharedMenu}" />
</UniformGrid>
</StackPanel>
But it isn't behaving as expected. If you try clicking a button, the ContextMenu pops up but without having it's DataContext set.
If I manually set the DataContext like this :
ContextMenu = (ContextMenu)DropdownContent;
ContextMenu.DataContext = DataContext;
ContextMenu.IsOpen = true;
it breaks the binding on the TextBlocks ContextMenu
To be perfectly honest, I don't know why this works, but if I apply the following change :
protected override void OnClick()
{
base.OnClick();
if (DropdownContent != null)
{
if (DropdownContent is ContextMenu)
{
ContextMenu = (ContextMenu)DropdownContent;
ContextMenu.PlacementTarget = this;
ContextMenu.IsOpen = true;
}
else
{
// launch a popup
}
}
}
As well as disable Menu animations :
<Application.Resources>
<PopupAnimation x:Key="{x:Static SystemParameters.MenuPopupAnimationKey}">None</PopupAnimation>
</Application.Resources>
Things work ...

Locking popup position to element, or faking a popup with layers for in-place editing in an ItemsControl

What I am trying to achieve is essentially in-place editing of a databound object inside an ItemsControl in wpf.
my ItemsControl is a horizontal WrapPanel containing multiple instances of a usercontrol (NameControl) which displays as a little pink Glyph with a person's name. It looks like this
With a popup I am able to show an editor for this "Name" (Other properties of the bound object things like Address,Gender etc.) and this works absoluttely fine. My XAML at this point would be along the lines of
<Style x:Key="NamesStyle" TargetType="{x:Type ItemsControl}">
<Setter Property="ItemsPanel">
<Setter.Value>
<ItemsPanelTemplate>
<WrapPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</Setter.Value>
</Setter>
<Setter Property="ItemTemplate">
<Setter.Value>
<DataTemplate>
<StackPanel>
<Button Command="{Binding EditName}" BorderThickness="0" Background="Transparent" Panel.ZIndex="1">
<widgets:NameControl />
</Button>
<Popup IsOpen="{Binding IsEditMode}"
PlacementTarget="{Binding ElementName=button}"
Margin="0 5 0 0" Placement="Relative" AllowsTransparency="True" >
<Border Background="White" BorderBrush="DarkOrchid" BorderThickness="1,1,1,1" CornerRadius="5,5,5,5"
Panel.ZIndex="100">
<Grid ShowGridLines="False" Margin="5" Background="White" Width="300">
<!-- Grid Content - just editor fields/button etc -->
</Grid>
</Border>
</Popup>
</StackPanel>
</DataTemplate>
</Setter.Value>
</Setter>
</Style>
Giving an output when I click a Name looking like
With this look im quite happy (apart from my awful choice of colours!!) except that the popup does not move with the widow (resize/minimize/maximize) and that popup is above everything even other windows.
So one way to solve part of that is to "attach" or lock the popup position to the element. I have not found a good/easy/xaml way to do that. Ive come across a few code-based solutions but im not sure I like that. It just has a bit of a smell about it.
Another solution ive tried to achieve is to ditch the popup and try to emulate the behaviour of a layer/panel that sits above the other names but is position over (or below, im not fussy) the associated name control.
Ive tried a few different things, mainly around setting Panel.ZIndex on controls within a PanelControl (The Grid, the WrapPanel, a DockPanel on the very top of my MainWindow) with little success. I have implemented a simple BoolToVisibilityConverter to bind my editor Grid's Visibility property to my IsEditMode view model property and that works fine, but I cant for the life of me arrange my elements in the ItemsControl to show the editor grid over the names.
To do what is described above I simply commented out the Popup and added the following binding to the Border which contains the editor grid Visibility="{Binding IsEditMode, Converter={StaticResource boolToVisibility}}".
All that does is this:
It just shows the popup under the name but not over the others.
Any help? What am I doing wrong?
Sounds like a job for the AdornerLayer to me.
My implementation will just display one 'popup' at a time, and you can hide it by clicking the button another time. But you could also add a small close button to the ContactAdorner, or stick with your OK button, or fill the AdornerLayer behind the ContactAdorner with an element that IsHitTestVisible and reacts on click by hiding the open Adorner (so clicking anywhere outside closes the popup).
Edit: Added the small close button at your request. Changes in ContactAdorner and the ContactDetailsTemplate.
Another thing that you might want to add is repositioning of the adorner once it is clipped from the bottom (I only check for clipping from the right).
Xaml:
<UserControl x:Class="WpfApplication1.ItemsControlAdorner"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
mc:Ignorable="d"
xmlns:local="clr-namespace:WpfApplication1"
d:DesignHeight="300" d:DesignWidth="300">
<UserControl.DataContext>
<local:ViewModel />
</UserControl.DataContext>
<UserControl.Resources>
<local:EnumToBooleanConverter x:Key="EnumToBooleanConverter" />
<!-- Template for the Adorner -->
<DataTemplate x:Key="ContactDetailsTemplate" DataType="{x:Type local:MyContact}" >
<Border Background="#BBFFFFFF" BorderBrush="DarkOrchid" BorderThickness="1" CornerRadius="5" TextElement.Foreground="DarkOrchid" >
<Grid Margin="5" Width="300">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<TextBlock Text="Full name" />
<TextBox Grid.Row="1" Text="{Binding FullName, UpdateSourceTrigger=PropertyChanged}" />
<TextBlock Grid.Row="2" Text="Address" />
<TextBox Grid.Row="3" Grid.ColumnSpan="2" Text="{Binding Address}" />
<TextBlock Grid.Column="1" Text="Gender" />
<StackPanel Orientation="Horizontal" Grid.Column="1" Grid.Row="1" >
<RadioButton Content="Male" IsChecked="{Binding Gender, Converter={StaticResource EnumToBooleanConverter}, ConverterParameter={x:Static local:Gender.Male}}" />
<RadioButton Content="Female" IsChecked="{Binding Gender, Converter={StaticResource EnumToBooleanConverter}, ConverterParameter={x:Static local:Gender.Female}}" />
</StackPanel>
<Button x:Name="PART_CloseButton" Grid.Column="2" Height="16">
<Button.Template>
<ControlTemplate>
<Border Background="#01FFFFFF" Padding="3" >
<Path Stretch="Uniform" ClipToBounds="True" Stroke="DarkOrchid" StrokeThickness="2.5" Data="M 85.364473,6.9977109 6.0640998,86.29808 6.5333398,85.76586 M 6.9926698,7.4977169 86.293043,86.79809 85.760823,86.32885" />
</Border>
</ControlTemplate>
</Button.Template>
</Button>
</Grid>
</Border>
</DataTemplate>
<!-- Button/Item style -->
<Style x:Key="ButtonStyle1" TargetType="{x:Type Button}" >
<Setter Property="Foreground" Value="White" />
<Setter Property="FontFamily" Value="Times New Roman" />
<Setter Property="Background" Value="#CC99E6" />
<Setter Property="BorderThickness" Value="0" />
<Setter Property="MinHeight" Value="24" />
<Setter Property="Margin" Value="3,2" />
<Setter Property="Padding" Value="3,2" />
<Setter Property="Border.CornerRadius" Value="8" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Border CornerRadius="{TemplateBinding Border.CornerRadius}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Padding="{TemplateBinding Padding}" Margin="{TemplateBinding Margin}" >
<ContentPresenter VerticalAlignment="Center" HorizontalAlignment="Center" />
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<!-- ItemsControl style -->
<Style x:Key="NamesStyle" TargetType="{x:Type ItemsControl}">
<Setter Property="ItemsPanel">
<Setter.Value>
<ItemsPanelTemplate>
<WrapPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</Setter.Value>
</Setter>
<Setter Property="ItemTemplate">
<Setter.Value>
<DataTemplate>
<Button x:Name="button" Style="{StaticResource ButtonStyle1}" Content="{Binding FullName}" >
<i:Interaction.Behaviors>
<local:ShowAdornerBehavior DataTemplate="{StaticResource ContactDetailsTemplate}" />
</i:Interaction.Behaviors>
</Button>
</DataTemplate>
</Setter.Value>
</Setter>
</Style>
</UserControl.Resources>
<Grid>
<ItemsControl ItemsSource="{Binding MyContacts}" Style="{StaticResource NamesStyle}" />
</Grid>
</UserControl>
ShowAdornerBehavior, ContactAdorner, EnumToBooleanConverter:
using System.Windows;
using System.Linq;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Interactivity;
using System.Windows.Media;
using System.Windows.Data;
using System;
namespace WpfApplication1
{
public class ShowAdornerBehavior : Behavior<Button>
{
public DataTemplate DataTemplate { get; set; }
protected override void OnAttached()
{
this.AssociatedObject.Click += AssociatedObject_Click;
base.OnAttached();
}
void AssociatedObject_Click(object sender, RoutedEventArgs e)
{
var adornerLayer = AdornerLayer.GetAdornerLayer(this.AssociatedObject);
var contactAdorner = new ContactAdorner(this.AssociatedObject, adornerLayer, this.AssociatedObject.DataContext, this.DataTemplate);
}
}
public class ContactAdorner : Adorner
{
private ContentPresenter _contentPresenter;
private AdornerLayer _adornerLayer;
private static Button _btn;
private VisualCollection _visualChildren;
private double _marginRight = 5;
private double _adornerDistance = 5;
private PointCollection _points;
private static ContactAdorner _currentInstance;
public ContactAdorner(Button adornedElement, AdornerLayer adornerLayer, object data, DataTemplate dataTemplate)
: base(adornedElement)
{
if (_currentInstance != null)
_currentInstance.Hide(); // hides other adorners of the same type
if (_btn != null && _btn == adornedElement)
{
_currentInstance.Hide(); // hides the adorner of this button (toggle)
_btn = null;
}
else
{
_adornerLayer = adornerLayer;
_btn = adornedElement;
// adjust position if sizes change
_adornerLayer.SizeChanged += (s, e) => { UpdatePosition(); };
_btn.SizeChanged += (s, e) => { UpdatePosition(); };
_contentPresenter = new ContentPresenter() { Content = data, ContentTemplate = dataTemplate };
// apply template explicitly: http://stackoverflow.com/questions/5679648/why-would-this-contenttemplate-findname-throw-an-invalidoperationexception-on
_contentPresenter.ApplyTemplate();
// get close button from datatemplate
Button closeBtn = _contentPresenter.ContentTemplate.FindName("PART_CloseButton", _contentPresenter) as Button;
if (closeBtn != null)
closeBtn.Click += (s, e) => { this.Hide(); _btn = null; };
_visualChildren = new VisualCollection(this); // this is needed for user interaction with the adorner layer
_visualChildren.Add(_contentPresenter);
_adornerLayer.Add(this);
_currentInstance = this;
UpdatePosition(); // position adorner
}
}
/// <summary>
/// Positioning is a bit fiddly.
/// Also, this method is only dealing with the right clip, not yet with the bottom clip.
/// </summary>
private void UpdatePosition()
{
double marginLeft = 0;
_contentPresenter.Margin = new Thickness(marginLeft, 0, _marginRight, 0); // "reset" margin to get a good measure pass
_contentPresenter.Measure(_adornerLayer.RenderSize); // measure the contentpresenter to get a DesiredSize
var contentRect = new Rect(_contentPresenter.DesiredSize);
double right = _btn.TranslatePoint(new Point(contentRect.Width, 0), _adornerLayer).X; // this does not work with the contentpresenter, so use _adornedElement
if (right > _adornerLayer.ActualWidth) // if adorner is clipped by right window border, move it to the left
marginLeft = _adornerLayer.ActualWidth - right;
_contentPresenter.Margin = new Thickness(marginLeft, _btn.ActualHeight + _adornerDistance, _marginRight, 0); // position adorner
DrawArrow();
}
private void DrawArrow()
{
Point bottomMiddleButton = new Point(_btn.ActualWidth / 2, _btn.ActualHeight - _btn.Margin.Bottom);
Point topLeftAdorner = new Point(_btn.ActualWidth / 2 - 10, _contentPresenter.Margin.Top);
Point topRightAdorner = new Point(_btn.ActualWidth / 2 + 10, _contentPresenter.Margin.Top);
PointCollection points = new PointCollection();
points.Add(bottomMiddleButton);
points.Add(topLeftAdorner);
points.Add(topRightAdorner);
_points = points; // actual drawing executed in OnRender
}
protected override void OnRender(DrawingContext drawingContext)
{
// Drawing the arrow
StreamGeometry streamGeometry = new StreamGeometry();
using (StreamGeometryContext geometryContext = streamGeometry.Open())
{
if (_points != null && _points.Any())
{
geometryContext.BeginFigure(_points[0], true, true);
geometryContext.PolyLineTo(_points.Where(p => _points.IndexOf(p) > 0).ToList(), true, true);
}
}
// Draw the polygon visual
drawingContext.DrawGeometry(Brushes.DarkOrchid, new Pen(_btn.Background, 0.5), streamGeometry);
base.OnRender(drawingContext);
}
private void Hide()
{
_adornerLayer.Remove(this);
}
protected override Size MeasureOverride(Size constraint)
{
_contentPresenter.Measure(constraint);
return _contentPresenter.DesiredSize;
}
protected override Size ArrangeOverride(Size finalSize)
{
_contentPresenter.Arrange(new Rect(finalSize));
return finalSize;
}
protected override Visual GetVisualChild(int index)
{
return _visualChildren[index];
}
protected override int VisualChildrenCount
{
get { return _visualChildren.Count; }
}
}
// http://stackoverflow.com/questions/397556/how-to-bind-radiobuttons-to-an-enum
public class EnumToBooleanConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
return value.Equals(parameter);
}
public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
return value.Equals(true) ? parameter : Binding.DoNothing;
}
}
}
ViewModel, MyContact:
using System;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Windows.Input;
namespace WpfApplication1
{
public class ViewModel : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged(string propertyName)
{
if (this.PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
private ObservableCollection<MyContact> _myContacts = new ObservableCollection<MyContact>();
public ObservableCollection<MyContact> MyContacts { get { return _myContacts; } set { _myContacts = value; OnPropertyChanged("MyContacts"); } }
public ViewModel()
{
MyContacts = new ObservableCollection<MyContact>()
{
new MyContact() { FullName = "Sigmund Freud", Gender = Gender.Male },
new MyContact() { FullName = "Abraham Lincoln", Gender = Gender.Male },
new MyContact() { FullName = "Joan Of Arc", Gender = Gender.Female },
new MyContact() { FullName = "Bob the Khann", Gender = Gender.Male, Address = "Mongolia" },
new MyContact() { FullName = "Freddy Mercury", Gender = Gender.Male },
new MyContact() { FullName = "Giordano Bruno", Gender = Gender.Male },
new MyContact() { FullName = "Socrates", Gender = Gender.Male },
new MyContact() { FullName = "Marie Curie", Gender = Gender.Female }
};
}
}
public class MyContact : INotifyPropertyChanged
{
private string _fullName;
public string FullName { get { return _fullName; } set { _fullName = value; OnPropertyChanged("FullName"); } }
private string _address;
public string Address { get { return _address; } set { _address = value; OnPropertyChanged("Address"); } }
private Gender _gender;
public Gender Gender { get { return _gender; } set { _gender = value; OnPropertyChanged("Gender"); } }
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged(string propertyName)
{
if (this.PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
public enum Gender
{
Male,
Female
}
Personally I hate WPF's built in Popup control for exactly those reasons, and my workaround is to use a Custom Popup UserControl
Basically I'll put the Popup in a panel that allows it's children to overlap, such as a Grid or a Canvas, and position it on top of whatever content it's supposed to be on top of.
It includes DependencyProperties to specify it's parent panel and if it's open or not, and is part of the normal VisualTree so it will move around with your Window and act the same way any regular UI element would.
Typical usage would look like this:
<Grid x:Name="ParentPanel">
<ItemsControl ... />
<local:PopupPanel Content="{Binding PopupContent}"
local:PopupPanel.PopupParent="{Binding ElementName=ParentPanel}"
local:PopupPanel.IsPopupVisible="{Binding IsPopupVisible}" />
</Grid>
The code for the UserControl can be found on my blog along with a downloadable example of its use, but I'll also post a copy of it here.
The XAML for the UserControl is:
<UserControl x:Class="PopupPanelSample.PopupPanel"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:PopupPanelSample"
FocusManager.IsFocusScope="True"
>
<UserControl.Template>
<ControlTemplate TargetType="{x:Type local:PopupPanel}">
<ControlTemplate.Resources>
<!-- Converter to get Popup Positioning -->
<local:ValueDividedByParameterConverter x:Key="ValueDividedByParameterConverter" />
<!-- Popup Visibility -->
<BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter" />
<Style x:Key="PopupPanelContentStyle" TargetType="{x:Type Grid}">
<Setter Property="Grid.Visibility" Value="{Binding Path=IsPopupVisible,
RelativeSource={RelativeSource AncestorType={x:Type local:PopupPanel}},
Converter={StaticResource BooleanToVisibilityConverter}}"/>
</Style>
</ControlTemplate.Resources>
<Grid x:Name="PopupPanelContent" Style="{StaticResource PopupPanelContentStyle}">
<Grid.Resources>
<!-- Storyboard to show Content -->
<Storyboard x:Key="ShowEditPanelStoryboard" SpeedRatio="5">
<DoubleAnimation
Storyboard.TargetName="PopupPanelContent"
Storyboard.TargetProperty="RenderTransform.(ScaleTransform.ScaleX)"
From="0.00" To="1.00" Duration="00:00:01"
/>
<DoubleAnimation
Storyboard.TargetName="PopupPanelContent"
Storyboard.TargetProperty="RenderTransform.(ScaleTransform.ScaleY)"
From="0.00" To="1.00" Duration="00:00:01"
/>
</Storyboard>
</Grid.Resources>
<!-- Setting up RenderTransform for Popup Animation -->
<Grid.RenderTransform>
<ScaleTransform
CenterX="{Binding Path=PopupParent.ActualWidth, Converter={StaticResource ValueDividedByParameterConverter}, ConverterParameter=2, RelativeSource={RelativeSource AncestorType={x:Type local:PopupPanel}}}"
CenterY="{Binding Path=PopupParent.ActualHeight, Converter={StaticResource ValueDividedByParameterConverter}, ConverterParameter=2, RelativeSource={RelativeSource AncestorType={x:Type local:PopupPanel}}}"
/>
</Grid.RenderTransform>
<!-- Grayscale background & prevents mouse input -->
<Rectangle
Fill="Gray"
Opacity="{Binding Path=BackgroundOpacity, RelativeSource={RelativeSource AncestorType={x:Type local:PopupPanel}}}"
Height="{Binding RelativeSource={RelativeSource AncestorType={x:Type local:PopupPanel}}, Path=Height}"
Width="{Binding RelativeSource={RelativeSource AncestorType={x:Type local:PopupPanel}}, Path=Width}"
/>
<!-- Popup Content -->
<ContentControl x:Name="PopupContentControl"
KeyboardNavigation.TabNavigation="Cycle"
PreviewKeyDown="PopupPanel_PreviewKeyDown"
PreviewLostKeyboardFocus="PopupPanel_LostFocus"
IsVisibleChanged="PopupPanel_IsVisibleChanged"
HorizontalAlignment="Center" VerticalAlignment="Center"
>
<ContentPresenter Content="{TemplateBinding Content}" />
</ContentControl>
</Grid>
</ControlTemplate>
</UserControl.Template>
</UserControl>
And the code-behind the UserControl looks like this:
using System;
using System.ComponentModel;
using System.Globalization;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Threading;
namespace PopupPanelSample
{
/// <summary>
/// Panel for handling Popups:
/// - Control with name PART_DefaultFocusControl will have default focus
/// - Can define PopupParent to determine if this popup should be hosted in a parent panel or not
/// - Can define the property EnterKeyCommand to specifify what command to run when the Enter key is pressed
/// - Can define the property EscapeKeyCommand to specify what command to run when the Escape key is pressed
/// - Can define BackgroundOpacity to specify how opaque the background will be. Value is between 0 and 1.
/// </summary>
public partial class PopupPanel : UserControl
{
#region Fields
bool _isLoading = false; // Flag to tell identify when DataContext changes
private UIElement _lastFocusControl; // Last control that had focus when popup visibility changes, but isn't closed
#endregion // Fields
#region Constructors
public PopupPanel()
{
InitializeComponent();
this.DataContextChanged += Popup_DataContextChanged;
// Register a PropertyChanged event on IsPopupVisible
DependencyPropertyDescriptor dpd = DependencyPropertyDescriptor.FromProperty(PopupPanel.IsPopupVisibleProperty, typeof(PopupPanel));
if (dpd != null) dpd.AddValueChanged(this, delegate { IsPopupVisible_Changed(); });
dpd = DependencyPropertyDescriptor.FromProperty(PopupPanel.ContentProperty, typeof(PopupPanel));
if (dpd != null) dpd.AddValueChanged(this, delegate { Content_Changed(); });
}
#endregion // Constructors
#region Events
#region Property Change Events
// When DataContext changes
private void Popup_DataContextChanged(object sender, DependencyPropertyChangedEventArgs e)
{
DisableAnimationWhileLoading();
}
// When Content Property changes
private void Content_Changed()
{
DisableAnimationWhileLoading();
}
// Sets an IsLoading flag so storyboard doesn't run while loading
private void DisableAnimationWhileLoading()
{
_isLoading = true;
this.Dispatcher.BeginInvoke(DispatcherPriority.Render,
new Action(delegate() { _isLoading = false; }));
}
// Run storyboard when IsPopupVisible property changes to true
private void IsPopupVisible_Changed()
{
bool isShown = GetIsPopupVisible(this);
if (isShown && !_isLoading)
{
FrameworkElement panel = FindChild<FrameworkElement>(this, "PopupPanelContent");
if (panel != null)
{
// Run Storyboard
Storyboard animation = (Storyboard)panel.FindResource("ShowEditPanelStoryboard");
animation.Begin();
}
}
// When hiding popup, clear the LastFocusControl
if (!isShown)
{
_lastFocusControl = null;
}
}
#endregion // Change Events
#region Popup Events
// When visibility is changed, set the default focus
void PopupPanel_IsVisibleChanged(object sender, DependencyPropertyChangedEventArgs e)
{
if ((bool)e.NewValue)
{
ContentControl popupControl = FindChild<ContentControl>(this, "PopupContentControl");
this.Dispatcher.BeginInvoke(DispatcherPriority.Render,
new Action(delegate()
{
// Verify object really is visible because sometimes it's not once we switch to Render
if (!GetIsPopupVisible(this))
{
return;
}
if (_lastFocusControl != null && _lastFocusControl.Focusable)
{
_lastFocusControl.Focus();
}
else
{
_lastFocusControl = FindChild<UIElement>(popupControl, "PART_DefaultFocusControl") as UIElement;
// If we can find the part named PART_DefaultFocusControl, set focus to it
if (_lastFocusControl != null && _lastFocusControl.Focusable)
{
_lastFocusControl.Focus();
}
else
{
_lastFocusControl = FindFirstFocusableChild(popupControl);
// If no DefaultFocusControl found, try and set focus to the first focusable element found in popup
if (_lastFocusControl != null)
{
_lastFocusControl.Focus();
}
else
{
// Just give the Popup UserControl focus so it can handle keyboard input
popupControl.Focus();
}
}
}
}
)
);
}
}
// When popup loses focus but isn't hidden, store the last element that had focus so we can put it back later
void PopupPanel_LostFocus(object sender, RoutedEventArgs e)
{
DependencyObject focusScope = FocusManager.GetFocusScope(this);
_lastFocusControl = FocusManager.GetFocusedElement(focusScope) as UIElement;
}
// Keyboard Events
private void PopupPanel_PreviewKeyDown(object sender, KeyEventArgs e)
{
if (e.Key == Key.Escape)
{
PopupPanel popup = FindAncester<PopupPanel>((DependencyObject)sender);
ICommand cmd = GetPopupEscapeKeyCommand(popup);
if (cmd != null && cmd.CanExecute(null))
{
cmd.Execute(null);
e.Handled = true;
}
else
{
// By default the Escape Key closes the popup when pressed
var expression = this.GetBindingExpression(PopupPanel.IsPopupVisibleProperty);
var dataType = expression.DataItem.GetType();
dataType.GetProperties().Single(x => x.Name == expression.ParentBinding.Path.Path)
.SetValue(expression.DataItem, false, null);
}
}
else if (e.Key == Key.Enter)
{
// Don't want to run Enter command if focus is in a TextBox with AcceptsReturn = True
if (!(e.KeyboardDevice.FocusedElement is TextBox &&
(e.KeyboardDevice.FocusedElement as TextBox).AcceptsReturn == true))
{
PopupPanel popup = FindAncester<PopupPanel>((DependencyObject)sender);
ICommand cmd = GetPopupEnterKeyCommand(popup);
if (cmd != null && cmd.CanExecute(null))
{
cmd.Execute(null);
e.Handled = true;
}
}
}
}
#endregion // Popup Events
#endregion // Events
#region Dependency Properties
// Parent for Popup
#region PopupParent
public static readonly DependencyProperty PopupParentProperty =
DependencyProperty.Register("PopupParent", typeof(FrameworkElement),
typeof(PopupPanel), new PropertyMetadata(null, null, CoercePopupParent));
private static object CoercePopupParent(DependencyObject obj, object value)
{
// If PopupParent is null, return the Window object
return (value ?? FindAncester<Window>(obj));
}
public FrameworkElement PopupParent
{
get { return (FrameworkElement)this.GetValue(PopupParentProperty); }
set { this.SetValue(PopupParentProperty, value); }
}
// Providing Get/Set methods makes them show up in the XAML designer
public static FrameworkElement GetPopupParent(DependencyObject obj)
{
return (FrameworkElement)obj.GetValue(PopupParentProperty);
}
public static void SetPopupParent(DependencyObject obj, FrameworkElement value)
{
obj.SetValue(PopupParentProperty, value);
}
#endregion
// Popup Visibility - If popup is shown or not
#region IsPopupVisibleProperty
public static readonly DependencyProperty IsPopupVisibleProperty =
DependencyProperty.Register("IsPopupVisible", typeof(bool),
typeof(PopupPanel), new PropertyMetadata(false, null));
public static bool GetIsPopupVisible(DependencyObject obj)
{
return (bool)obj.GetValue(IsPopupVisibleProperty);
}
public static void SetIsPopupVisible(DependencyObject obj, bool value)
{
obj.SetValue(IsPopupVisibleProperty, value);
}
#endregion // IsPopupVisibleProperty
// Transparency level for the background filler outside the popup
#region BackgroundOpacityProperty
public static readonly DependencyProperty BackgroundOpacityProperty =
DependencyProperty.Register("BackgroundOpacity", typeof(double),
typeof(PopupPanel), new PropertyMetadata(.5, null));
public static double GetBackgroundOpacity(DependencyObject obj)
{
return (double)obj.GetValue(BackgroundOpacityProperty);
}
public static void SetBackgroundOpacity(DependencyObject obj, double value)
{
obj.SetValue(BackgroundOpacityProperty, value);
}
#endregion ShowBackgroundProperty
// Command to execute when Enter key is pressed
#region PopupEnterKeyCommandProperty
public static readonly DependencyProperty PopupEnterKeyCommandProperty =
DependencyProperty.RegisterAttached("PopupEnterKeyCommand", typeof(ICommand),
typeof(PopupPanel), new PropertyMetadata(null, null));
public static ICommand GetPopupEnterKeyCommand(DependencyObject obj)
{
return (ICommand)obj.GetValue(PopupEnterKeyCommandProperty);
}
public static void SetPopupEnterKeyCommand(DependencyObject obj, ICommand value)
{
obj.SetValue(PopupEnterKeyCommandProperty, value);
}
#endregion PopupEnterKeyCommandProperty
// Command to execute when Enter key is pressed
#region PopupEscapeKeyCommandProperty
public static readonly DependencyProperty PopupEscapeKeyCommandProperty =
DependencyProperty.RegisterAttached("PopupEscapeKeyCommand", typeof(ICommand),
typeof(PopupPanel), new PropertyMetadata(null, null));
public static ICommand GetPopupEscapeKeyCommand(DependencyObject obj)
{
return (ICommand)obj.GetValue(PopupEscapeKeyCommandProperty);
}
public static void SetPopupEscapeKeyCommand(DependencyObject obj, ICommand value)
{
obj.SetValue(PopupEscapeKeyCommandProperty, value);
}
#endregion PopupEscapeKeyCommandProperty
#endregion Dependency Properties
#region Visual Tree Helpers
public static UIElement FindFirstFocusableChild(DependencyObject parent)
{
// Confirm parent is valid.
if (parent == null) return null;
UIElement foundChild = null;
int childrenCount = VisualTreeHelper.GetChildrenCount(parent);
for (int i = 0; i < childrenCount; i++)
{
UIElement child = VisualTreeHelper.GetChild(parent, i) as UIElement;
// This is returning me things like ContentControls, so for now filtering to buttons/textboxes only
if (child != null && child.Focusable && child.IsVisible)
{
foundChild = child;
break;
}
// recursively drill down the tree
foundChild = FindFirstFocusableChild(child);
// If the child is found, break so we do not overwrite the found child.
if (foundChild != null) break;
}
return foundChild;
}
public static T FindAncester<T>(DependencyObject current)
where T : DependencyObject
{
// Need this call to avoid returning current object if it is the same type as parent we are looking for
current = VisualTreeHelper.GetParent(current);
while (current != null)
{
if (current is T)
{
return (T)current;
}
current = VisualTreeHelper.GetParent(current);
};
return null;
}
/// <summary>
/// Looks for a child control within a parent by name
/// </summary>
public static T FindChild<T>(DependencyObject parent, string childName)
where T : DependencyObject
{
// Confirm parent and childName are valid.
if (parent == null) return null;
T foundChild = null;
int childrenCount = VisualTreeHelper.GetChildrenCount(parent);
for (int i = 0; i < childrenCount; i++)
{
var child = VisualTreeHelper.GetChild(parent, i);
// If the child is not of the request child type child
T childType = child as T;
if (childType == null)
{
// recursively drill down the tree
foundChild = FindChild<T>(child, childName);
// If the child is found, break so we do not overwrite the found child.
if (foundChild != null) break;
}
else if (!string.IsNullOrEmpty(childName))
{
var frameworkElement = child as FrameworkElement;
// If the child's name is set for search
if (frameworkElement != null && frameworkElement.Name == childName)
{
// if the child's name is of the request name
foundChild = (T)child;
break;
}
else
{
// recursively drill down the tree
foundChild = FindChild<T>(child, childName);
// If the child is found, break so we do not overwrite the found child.
if (foundChild != null) break;
}
}
else
{
// child element found.
foundChild = (T)child;
break;
}
}
return foundChild;
}
#endregion
}
// Converter for Popup positioning
public class ValueDividedByParameterConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
double n, d;
if (double.TryParse(value.ToString(), out n)
&& double.TryParse(parameter.ToString(), out d)
&& d != 0)
{
return n / d;
}
return 0;
} public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
throw new NotImplementedException();
}
}
}

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