How to use ColumnDefinitions.Add correctly? - wpf

Question

I copied an example about dock panel from "WPF 4.5 Unleashed" ch.5. In the example the dock is set to be in the right of the grid So when in the code behind layer0.ColumnDefinitions.Add(column1CloneForLayer0); called, a column with content column1CloneForLayer0 will be created in the right side of the grid.
In my project I almost did the same thing, but when I call the function to add a column with some content, some empty space's created at the right side.. which is not as expected.So what's the right thing to do?
1.How to Add a column in the left side of a grid?
2.In the example the column was created yet why it's empty? Maybe Do i need to set the Z Index?
Update
I added something similar in the original example in the book and get wrong result. Below is the the source codes. I just added a leftToolBox in the left.
https://www.dropbox.com/sh/61hm139j77kz9k1/AACKqhG5uXFkQgnt8fWi4NvNa?dl=0
Update2
Relevant codes: In this case I just add a stackpanel with button in the left side and and click to call DocakPane(3), instead of giving the new column in the left, it creates column in the right.
public void DockPane(int paneNumber)
{
if (paneNumber == 1)
{
pane1Button.Visibility = Visibility.Collapsed;
pane1PinImage.Source = new BitmapImage(new Uri("pin.gif", UriKind.Relative));
// Add the cloned column to layer 0:
layer0.ColumnDefinitions.Add(column1CloneForLayer0);
// Add the cloned column to layer 1, but only if pane 2 is docked:
if (pane2Button.Visibility == Visibility.Collapsed) layer1.ColumnDefinitions.Add(column2CloneForLayer1);
}
else if (paneNumber == 2)
{
pane2Button.Visibility = Visibility.Collapsed;
pane2PinImage.Source = new BitmapImage(new Uri("pin.gif", UriKind.Relative));
// Add the cloned column to layer 0:
layer0.ColumnDefinitions.Add(column2CloneForLayer0);
// Add the cloned column to layer 1, but only if pane 1 is docked:
if (pane1Button.Visibility == Visibility.Collapsed) layer1.ColumnDefinitions.Add(column2CloneForLayer1);
}
else
{
leftpane1Button.Visibility = Visibility.Collapsed;
pane3PinImage.Source = new BitmapImage(new Uri("pin.gif", UriKind.Relative));
layer0.ColumnDefinitions.Add(testcol);
}
}

Answer 1

Based on the sample project provided, here is a re-write of the same using MVVM and most of the problem related to hard-coding would are gone. It is not pure MVVM but it is mostly MVVM to get started with.
start by defining ViewModels
a class to represent the dock pane
class DockablePaneVM : ViewModelBase
{
public DockablePaneVM(DockHostVM host)
{
Host = host;
}
private string _title;
public string Title
{
get { return _title; }
set
{
_title = value;
RaisePropertyChanged("Title");
}
}
private bool _isPinned;
public bool IsPinned
{
get { return _isPinned; }
set
{
_isPinned = value;
Host.PinModeChanged(this);
RaisePropertyChanged("IsPinned");
}
}
private object _content;
public object Content
{
get { return _content; }
set
{
_content = value;
RaisePropertyChanged("Content");
}
}
public DockHostVM Host { get; private set; }
public Dock Dock { get; set; }
}
host for the dockpanes, I have used collectionview for simplifying the location
class DockHostVM : ViewModelBase
{
public DockHostVM()
{
Panes = new ObservableCollection<DockablePaneVM>();
LeftPanes = new CollectionViewSource() { Source = Panes }.View;
RightPanes = new CollectionViewSource() { Source = Panes }.View;
FlotingLeftPanes = new CollectionViewSource() { Source = Panes }.View;
FlotingRightPanes = new CollectionViewSource() { Source = Panes }.View;
LeftPanes.Filter = o => Filter(o, Dock.Left, true);
RightPanes.Filter = o => Filter(o, Dock.Right, true);
FlotingLeftPanes.Filter = o => Filter(o, Dock.Left, false);
FlotingRightPanes.Filter = o => Filter(o, Dock.Right, false);
}
private bool Filter(object obj, Dock dock, bool isPinned)
{
DockablePaneVM vm = obj as DockablePaneVM;
return vm.Dock == dock && vm.IsPinned == isPinned;
}
public ObservableCollection<DockablePaneVM> Panes { get; set; }
public ICollectionView LeftPanes { get; set; }
public ICollectionView RightPanes { get; set; }
public ICollectionView FlotingLeftPanes { get; set; }
public ICollectionView FlotingRightPanes { get; set; }
private object _content;
public object Content
{
get { return _content; }
set { _content = value; }
}
public void PinModeChanged(DockablePaneVM paneVM)
{
LeftPanes.Refresh();
RightPanes.Refresh();
FlotingLeftPanes.Refresh();
FlotingRightPanes.Refresh();
}
//sample generator
public static DockHostVM GetSample()
{
DockHostVM vm = new DockHostVM();
vm.Panes.Add(new DockablePaneVM(vm) { Title = "Left Toolbox", Content = new ToolBoxVM() });
vm.Panes.Add(new DockablePaneVM(vm) { Title = "Solution Explorer", Content = new SolutionExplorerVM(), Dock = Dock.Right });
vm.Panes.Add(new DockablePaneVM(vm) { Title = "Toolbox", Content = new ToolBoxVM(), Dock = Dock.Right });
return vm;
}
}
then styles, to give provide the view for the classes
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:l="clr-namespace:VisualStudioLikePanes">
<DataTemplate DataType="{x:Type l:DockablePaneVM}">
<Grid Grid.Column="1">
<Grid.RowDefinitions>
<RowDefinition Height="auto" />
<RowDefinition />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition />
<ColumnDefinition Width="auto" />
</Grid.ColumnDefinitions>
<TextBlock Padding="8,4"
Text="{Binding Title}"
TextTrimming="CharacterEllipsis"
Background="{DynamicResource {x:Static SystemColors.ActiveCaptionBrushKey}}"
Foreground="{DynamicResource {x:Static SystemColors.ActiveCaptionTextBrushKey}}" />
<ToggleButton IsChecked="{Binding IsPinned}"
Grid.Column="1">
<Image Name="pinImage"
Source="pinHorizontal.gif" />
</ToggleButton>
<ContentControl Content="{Binding Content}"
Grid.Row="1"
Grid.ColumnSpan="2" />
</Grid>
<DataTemplate.Triggers>
<DataTrigger Binding="{Binding IsPinned}"
Value="True">
<Setter Property="Source"
TargetName="pinImage"
Value="pin.gif" />
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
<Style TargetType="TabItem">
<Setter Property="Header"
Value="{Binding Title}" />
</Style>
<Style TargetType="TabItem"
x:Key="FloterItem"
BasedOn="{StaticResource {x:Type TabItem}}">
<Setter Property="LayoutTransform">
<Setter.Value>
<RotateTransform Angle="90" />
</Setter.Value>
</Setter>
</Style>
<Style TargetType="TabControl">
<Setter Property="l:TabControlHelper.IsLastItemSelected"
Value="True" />
<Style.Triggers>
<Trigger Property="HasItems"
Value="false">
<Setter Property="Visibility"
Value="Collapsed" />
</Trigger>
</Style.Triggers>
</Style>
<Style TargetType="TabControl"
x:Key="AutoResizePane"
BasedOn="{StaticResource {x:Type TabControl}}">
<Style.Triggers>
<Trigger Property="IsMouseOver"
Value="false">
<Setter Property="Width"
Value="23" />
</Trigger>
</Style.Triggers>
</Style>
<DataTemplate DataType="{x:Type l:ToolBoxVM}">
<ListBox Padding="10"
Grid.Row="1">
<ListBoxItem>Button</ListBoxItem>
<ListBoxItem>CheckBox</ListBoxItem>
<ListBoxItem>ComboBox</ListBoxItem>
<ListBoxItem>Label</ListBoxItem>
<ListBoxItem>ListBox</ListBoxItem>
</ListBox>
</DataTemplate>
<DataTemplate DataType="{x:Type l:SolutionExplorerVM}">
<TreeView Grid.Row="2">
<TreeViewItem Header="My Solution" IsExpanded="True">
<TreeViewItem Header="Project #1" />
<TreeViewItem Header="Project #2" />
<TreeViewItem Header="Project #3" />
</TreeViewItem>
</TreeView>
</DataTemplate>
</ResourceDictionary>
I have also created some dummy classes to represent the toolbox and solution explorer
also a helper class to improve the usability of tab control which i have used to host the dockpanes
class TabControlHelper
{
public static bool GetIsLastItemSelected(DependencyObject obj)
{
return (bool)obj.GetValue(IsLastItemSelectedProperty);
}
public static void SetIsLastItemSelected(DependencyObject obj, bool value)
{
obj.SetValue(IsLastItemSelectedProperty, value);
}
// Using a DependencyProperty as the backing store for IsLastItemSelected. This enables animation, styling, binding, etc...
public static readonly DependencyProperty IsLastItemSelectedProperty =
DependencyProperty.RegisterAttached("IsLastItemSelected", typeof(bool), typeof(TabControlHelper), new PropertyMetadata(false, OnIsLastItemSelected));
private static void OnIsLastItemSelected(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
TabControl tc = d as TabControl;
tc.Items.CurrentChanged += (ss, ee) =>
{
if (tc.SelectedIndex < 0 && tc.Items.Count > 0)
tc.SelectedIndex = 0;
};
}
}
this will keep an item selected any time, in this project it will be used when a dock pane is pinned/unpinned
now the main window, note that I have bounded the dock Panes to 4 tab controls, left, right, left float & right float
<Window x:Class="VisualStudioLikePanes.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow"
Height="500"
Width="800"
WindowStartupLocation="CenterScreen"
xmlns:l="clr-namespace:VisualStudioLikePanes">
<Window.DataContext>
<ObjectDataProvider MethodName="GetSample"
ObjectType="{x:Type l:DockHostVM}" />
</Window.DataContext>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="auto" />
<RowDefinition />
</Grid.RowDefinitions>
<Menu>
<MenuItem Header="FILE" />
...
<MenuItem Header="HELP" />
</Menu>
<DockPanel LastChildFill="True"
Grid.Row="1">
<Border Width="23"
DockPanel.Dock="Left"
Visibility="{Binding Visibility, ElementName=LeftFloter}" />
<Border Width="23"
DockPanel.Dock="Right"
Visibility="{Binding Visibility, ElementName=RightFloter}" />
<TabControl ItemsSource="{Binding LeftPanes}"
DockPanel.Dock="Left" />
<TabControl ItemsSource="{Binding RightPanes}"
DockPanel.Dock="Right" />
<Grid Name="layer0">
... page content
</Grid>
</DockPanel>
<TabControl ItemsSource="{Binding FlotingLeftPanes}"
Grid.Row="1"
HorizontalAlignment="Left"
TabStripPlacement="Left"
Style="{StaticResource AutoResizePane}"
ItemContainerStyle="{StaticResource FloterItem}"
x:Name="LeftFloter" />
<TabControl ItemsSource="{Binding FlotingRightPanes}"
Grid.Row="1"
HorizontalAlignment="Right"
TabStripPlacement="Right"
Style="{StaticResource AutoResizePane}"
ItemContainerStyle="{StaticResource FloterItem}"
x:Name="RightFloter" />
</Grid>
</Window>
result is your expected behavior with MVVM approach, adding new panel is easy as Panes.Add(new DockablePaneVM(vm) { Title = "Left Toolbox", Content = new ToolBoxVM() }); rest is handled.
Demo
download the working sample VisualStudioLikePanes.zip