I am working in WPF with MVVM. I implemented WPF Extended Toolkit and I use ChildWindow, when I open the ChildWindow the property IsModal is enabled. But this property does not block navigating with Tab.
I need block the navigating with Tab when the ChildWindos is open.
I tried with Focusable property but does not serve.
I understand your issue is with the tab in the background when show the ChildWindow.
You should try modifying the property KeyboardNavigation.TabNavigation of de Window.
If you use MVVM pattern do something like this in the XAML:
<Window
KeyboardNavigation.TabNavigation="{Binding TabNavigationMode}"
>
In the ViewModel:
private KeyboardNavigationMode _tabNavigationMode;
public KeyboardNavigationMode TabNavigationMode
{
get { return _tabNavigationMode; }
set { _tabNavigationMode = value; RaisePropertyChanged("TabNavigationMode");
}
And create a Method like this that is invoked when you open and close the Child Window
public void IsTabNavigationEnable(bool isEnable)
{
if (isEnable) TabNavigationMode = KeyboardNavigationMode.Contained;
else TabNavigationMode = KeyboardNavigationMode.None;
}
I tried it and it works fine. The tab is disabled in the background but not in the ChildWindow.
This is a known issue and the extended tool kit team needs to work on it.In the mean time if you still like to implement this feature using the ChildWindow I would suggest to subscribe to PreviewKeyDown event and manually change the behavior of the tab and arrow keys when the childwindow goes modal.
The link for the issue is
https://wpftoolkit.codeplex.com/discussions/252462
I'm creating a epub books reader.
After displaying the book i want to allow users to add some annotation to the book.
To display the book, I'm using a wpf webbrowser control that loads local html files
I want to manipulate selected text on this control by creating a context menu or showing a popup
i've tried to change the control's contextmenu but by searching i found that isn't possible
this is an example of what i want to do with selected text:
IHTMLDocument2 htmlDocument = (IHTMLDocument2)webBrowser1.Document;
IHTMLSelectionObject currentSelection = htmlDocument.selection;
if (currentSelection != null)
{
IHTMLTxtRange range = currentSelection.createRange() as IHTMLTxtRange;
if (range != null)
{
MessageBox.Show(range.text);
}
}
WPF's native browser control will not let you set a custom context menu.
It gets even worse ; while your mouse is over the browser component, or if it has focus, it will not catch events generated by your input either.
A way around this, is to use the windows forms browser control inside a WindowsFormsHost.
To start, add Windows.Forms to your project references.
Then, do something like the following:
XAML:
<Window x:Class="blarb.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Grid>
<WindowsFormsHost Name="windowsFormsHost" VerticalAlignment="Stretch" HorizontalAlignment="Stretch"/>
</Grid>
</Window>
C# code:
public partial class MainWindow : Window
{
private System.Windows.Forms.WebBrowser Browser;
public MainWindow()
{
InitializeComponent();
//initialise the windows.forms browser component
Browser = new System.Windows.Forms.WebBrowser
{
//disable the default context menu
IsWebBrowserContextMenuEnabled = false
};
//make a custom context menu with items
System.Windows.Forms.ContextMenu BrowserContextMenu = new System.Windows.Forms.ContextMenu();
System.Windows.Forms.MenuItem MenuItem = new System.Windows.Forms.MenuItem {Text = "Take Action"};
MenuItem.Click += MenuItemOnClick;
BrowserContextMenu.MenuItems.Add(MenuItem);
Browser.ContextMenu = BrowserContextMenu;
//put the browser control in the windows forms host
windowsFormsHost.Child = Browser;
//navigate the browser like this:
Browser.Navigate("http://www.google.com");
}
private void MenuItemOnClick(object sender, EventArgs eventArgs)
{
//will be called when you click the context menu item
}
}
This does not yet explain how to do your highlighting though.
You could listen for the event fired by the browser component when it is done loading, and then replace portions of the document it loaded, injecting html code to do the highlighting.
Keep in mind that that might be tricky in some situations (when selecting text across divs, spans or paragraphs for example)
using mshtml;
private mshtml.HTMLDocumentEvents2_Event documentEvents;
in constructor or xaml set your LoadComplete event:
webBrowser.LoadCompleted += webBrowser_LoadCompleted;
then in that method create your new webbrowser document object and view the available properties and create new events as follows:
private void webBrowser_LoadCompleted(object sender, NavigationEventArgs e)
{
documentEvents = (HTMLDocumentEvents2_Event)webBrowserChat.Document; // this will access the events properties as needed
documentEvents.oncontextmenu += webBrowserChat_ContextMenuOpening;
}
private bool webBrowserChat_ContextMenuOpening(IHTMLEventObj pEvtObj)
{
return false; // ContextMenu wont open
// return true; ContextMenu will open
// Here you can create your custom contextmenu or whatever you want
}
I have a wpf usercontrol that contains an activex control housed in a windowsformhost.
I'm using an MVVM pattern that says
ViewModel1 is mapped to a Pure WPF View and
ViewModel2 is mapped to wpf content and the above usercontrol
If ViewModel2 is "Hidden" and then becomes Visible then the Activex control inside it doesn't show (Specifically I'm talking about the VLC activex control).
I've tested in a non MVVM pattern with a button and the usercontrol. The usercontrol is hidden until you press the button and the same thing happens but if I create a method in the usercontrol to re attach the activex control to the windowsformhost then it reappears. If I call this method from a viewmodel then it still remains blank. Does anyone know how I can get this to show again?
EDIT - I've just discovered it's because I have transparency on in my wpf application. It seems it's not possable to do what I want with windowsformshost and transparency enabled.
As there are no obvious answers I'll share my experience. When transparency is turned on in the wpf window then the windows form host doesn't refresh when changing from Hidden to Visable. I have found no way to make this work unless it is hosted in a new window with "Allowstransparency=false".
How are you setting up your active x control? The following Typically works for me in WPF if you are just needing it to attach to a grid. No user control required.:
//Active X Control initializer
private Ax addAxObject<Ax>(Grid container)
where Ax : System.Windows.Forms.Control, new()
{
Ax ax = new Ax();
var hoster = new System.Windows.Forms.Integration.WindowsFormsHost();
hoster.Child = (System.Windows.Forms.Control)ax;
container.Children.Add(hoster);
return ax;
}
private MyActiveXControl myActiveXControl;
public Grid InitializeActiveX(Grid grid)
{
myActiveXControl = addAxObject<myActiveXControl>(grid);
return grid;
}
Then all you do is is add it to your grid in your main window like so:
public MainWindow()
{
InitializeComponent();
//initialize Active X control
gridMain = InitializeActiveX(gridMain);
}
It shows up just fine for me. (Obviously not in the designer since it is programatically created)
I am designing a WPF user control which contains other user controls (imagine a WidgetContainer, containing different Widgets) - using M-V-VM architecture.
During development, I have WidgetContainerView in a window, window (View) spawns a WidgetContainerViewModel as its resource, and in a parameterless constructor of WidgetContainerViewModel, I fill its exposed collection with some sample widgets (WidgetViewModels).
WidgetContainer control inherits the DataContext from window, and inside, there is a ListView, that binds Widgets to WidgetView control (which is inside ListView.ItemTemplate).
Now this works OK in my WindowView, as I see my sample widgets, but once I edit the WidgetContainerView or WidgetView, there is no content - at design time, controls are standalone, and they don't inherit any DataContext, so I don't see a content, and have troubles designing them (a ListView is empty, Widget's fields as well...).
I tried adding a sample widget to the WidgetView:
public partial class WidgetView : UserControl
{
public WidgetView()
{
InitializeComponent();
if (LicenseManager.UsageMode == LicenseUsageMode.Designtime)
{
//btw, MessageBox.Show(...) here sometimes crashes my Visual Studio (2008), but I have seen the message - this code gets executed at design time, but with some lag - I saw the message on reload of designer, but at that time, I have already commented it - wtf?
this.DataContext = new WidgetViewModel(); //creates sample widget
}
}
}
but that didn't work - I still don't see anything in designer.
I also wanted to create a WidgetViewModel as a resource in WidgetView, like this:
<UserControl x:Class="MVVMTestWidgetsControl.View.WidgetView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
DataContext="WidgetViewModel" //this doesn't work!
Height="Auto" Width="Auto">
<UserControl.Resources>
<ResourceDictionary>
<ViewModel:WidgetViewModel x:Key="WidgetViewModel" />
</ResourceDictionary>
</UserControl.Resources>
<TextBlock Text="{Binding Path=Title}"></TextBlock>
</UserControl>
but I don't know how to assign a WidgetViewModel as a DataContext of a whole widget - I can't add DataContext attribute to UserControl, because WidgetViewModel is defined later in the code. Any ideas how to do this? I could use a sample data this way, and just override it in code so that it has the right content at runtime...
What are your best practices when developing user controls? Thank you, designing empty control is no fun :)).
In your second snippet, you should be able to refer to your DataContext as a DynamicResource:
DataContext="{DynamicResource WidgetViewModel}"
But most custom user controls have some sort of top level layout container, and you can set the DataContext on that container as a StaticResource.
In your case, however, you may want to consider dropping the VM portion of your code altogether since you're writing a custom UserControl. You should ask yourself what benefits are you gaining from a completely self-contained ViewModel with no real backing Model designed for just one View (i.e. the custom UserControl). Perhaps you could just define some DependencyProperties and use those?
I came up with several solutions: Add DC as resource (it will get automatically instantiated with parameterless constructor), and do the following in View's codebehind:
public PanelView()
{
InitializeComponent();
if (!DesignerProperties.GetIsInDesignMode(new DependencyObject())) //DeleteAtRelease:
{
//we are in runtime, reset DC to have it inherited
this.DataContextHolder.DataContext = DependencyProperty.UnsetValue;
}
}
Better way would be to only assign DC if we are at designtime, but VS didn't like it - it worked only sometimes, and quite nondeterministically, and once it even crashed.
Other check for design time is:
if (LicenseManager.UsageMode == LicenseUsageMode.Designtime)
{
this.DataContext = new WidgetViewModel();
}
I have a UserControl which contains a TextBox. When my main window loads I want to set the focus to this textbox so I added Focusable="True" GotFocus="UC_GotFocus" to the UserControls definition and FocusManager.FocusedElement="{Binding ElementName=login}" to my main windows definition. In the UC_GotFocus method i simply call .Focus() on the control i want to focus on but this doesn't work.
All i need to do is have a TextBox in a UserControl receive focus when the application starts.
Any help would be appreciated, thanks.
I recently fixed this problem for a login splash screen that is being displayed via a storyboard when the main window is first loaded.
I believe there were two keys to the fix. One was to make the containing element a focus scope. The other was to handle the Storyboard Completed event for the storyboard that was triggered by the window being loaded.
This storyboard makes the username and password canvas visible and then fades into being 100% opaque. The key is that the username control was not visible until the storyboard ran and therefore that control could not get keyboard focus until it was visible. What threw me off for awhile was that it had "focus" (i.e. focus was true, but as it turns out this was only logical focus) and I did not know that WPF had the concept of both logical and keyboard focus until reading Kent Boogaart's answer and looking at Microsoft's WPF link text
Once I did that the solution for my particular problem was straightforward:
1) Make the containing element a focus scope
<Canvas FocusManager.IsFocusScope="True" Visibility="Collapsed">
<TextBox x:Name="m_uxUsername" AcceptsTab="False" AcceptsReturn="False">
</TextBox>
</Canvas>
2) Attach a Completed Event Handler to the Storyboard
<Storyboard x:Key="Splash Screen" Completed="UserNamePassword_Storyboard_Completed">
...
</Storyboard>
and
3) Set my username TextBox to have the keyboard focus in the storyboard completed event handler.
void UserNamePassword_Storyboard_Completed(object sender, EventArgs e)
{
m_uxUsername.Focus();
}
Note that calling item.Focus() results in the call Keyboard.Focus(this), so you don't need to call this explicitly. See this question about the difference between Keyboard.Focus(item) and item.Focus.
Its stupid but it works:
Pop a thread that waits a while then comes back and sets the focus you want. It even works within the context of an element host.
private void ListView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
System.Threading.ThreadPool.QueueUserWorkItem(
(a) =>
{
System.Threading.Thread.Sleep(100);
someUiElementThatWantsFocus.Dispatcher.Invoke(
new Action(() =>
{
someUiElementThatWantsFocus.Focus();
}));
}
);
}
Just recently I had a list-box that housed some TextBlocks. I wanted to be able to double click on the text block and have it turn into a TextBox, then focus on it and select all the text so the user could just start typing the new name (Akin to Adobe Layers)
Anyway, I was doing this with an event and it just wasn't working. The magic bullet for me here was making sure that I set the event to handled. I figure it was setting focus, but as soon as the event went down the path it was switching the logical focus.
The moral of the story is, make sure you're marking the event as handled, that might be your issue.
“When setting initial focus at application startup, the element to
receive focus must be connected to a PresentationSource and the
element must have Focusable and IsVisible set to true. The recommended
place to set initial focus is in the Loaded event handler"
(MSDN)
Simply add a "Loaded" event handler in the constructor of your Window (or Control), and in that event handler call the Focus() method on the target control.
public MyWindow() {
InitializeComponent();
this.Loaded += new RoutedEventHandler(MyWindow_Loaded);
}
void MyWindow_Loaded(object sender, RoutedEventArgs e) {
textBox.Focus();
}
since i tried a fuzquat's solution and found it the most generic one, i thought i'd share a different version, since some complained about it looking messy. so here it is:
casted.Dispatcher.BeginInvoke(new Action<UIElement>(x =>
{
x.Focus();
}), DispatcherPriority.ApplicationIdle, casted);
no Thread.Sleep, no ThreadPool. Clean enough i hope.
UPDATE:
Since people seem to like pretty code:
public static class WpfExtensions
{
public static void BeginInvoke<T>(this T element, Action<T> action, DispatcherPriority priority = DispatcherPriority.ApplicationIdle) where T : UIElement
{
element.Dispatcher.BeginInvoke(priority, action);
}
}
now you can call it like this:
child.BeginInvoke(d => d.Focus());
WPF supports two different flavors of focus:
Keyboard focus
Logical focus
The FocusedElement property gets or sets logical focus within a focus scope. I suspect your TextBox does have logical focus, but its containing focus scope is not the active focus scope. Ergo, it does not have keyboard focus.
So the question is, do you have multiple focus scopes in your visual tree?
I found a good series of blog posts on WPF focus.
Part 1: It’s Basically Focus
Part 2: Changing WPF focus in code
Part 3: Shifting focus to the first available element in WPF
They are all good to read, but the 3rd part specifically deals with setting focus to a UI element in a UserControl.
Set your user control to Focusable="True" (XAML)
Handle the GotFocus event on your control and call yourTextBox.Focus()
Handle the Loaded event on your window and call yourControl.Focus()
I have a sample app running with this solution as I type. If this does not work for you, there must be something specific to your app or environment that causes the problem. In your original question, I think the binding is causing the problem.
I hope this helps.
After having a 'WPF Initial Focus Nightmare' and based on some answers on stack, the following proved for me to be the best solution.
First, add your App.xaml OnStartup() the followings:
EventManager.RegisterClassHandler(typeof(Window), Window.LoadedEvent,
new RoutedEventHandler(WindowLoaded));
Then add the 'WindowLoaded' event also in App.xaml :
void WindowLoaded(object sender, RoutedEventArgs e)
{
var window = e.Source as Window;
System.Threading.Thread.Sleep(100);
window.Dispatcher.Invoke(
new Action(() =>
{
window.MoveFocus(new TraversalRequest(FocusNavigationDirection.First));
}));
}
The threading issue must be use as WPF initial focus mostly fails due to some framework race conditions.
I found the following solution best as it is used globally for the whole app.
Hope it helps...
Oran
I converted fuzquat's answer to an extension method. I'm using this instead of Focus() where Focus() did not work.
using System;
using System.Threading;
using System.Windows;
namespace YourProject.Extensions
{
public static class UIElementExtension
{
public static void WaitAndFocus(this UIElement element, int ms = 100)
{
ThreadPool.QueueUserWorkItem(f =>
{
Thread.Sleep(ms);
element.Dispatcher.Invoke(new Action(() =>
{
element.Focus();
}));
});
}
}
}
I've noticed a focus issue specifically related to hosting WPF UserControls within ElementHosts which are contained within a Form that is set as an MDI child via the MdiParent property.
I'm not sure if this is the same issue others are experiencing but you dig into the details by following the link below.
Issue with setting focus within a WPF UserControl hosted within an ElementHost in a WindowsForms child MDI form
I don't like solutions with setting another tab scope for UserControl. In that case, you will have two different carets when navigating by keyboard: on the window and the another - inside user control. My solution is simply to redirect focus from user control to inner child control. Set user control focusable (because by default its false):
<UserControl ..... Focusable="True">
and override focus events handlers in code-behind:
protected override void OnGotFocus(RoutedEventArgs e)
{
base.OnGotFocus(e);
MyTextBox.Focus();
}
protected override void OnGotKeyboardFocus(KeyboardFocusChangedEventArgs e)
{
base.OnGotKeyboardFocus(e);
Keyboard.Focus(MyTextBox);
}
What did the trick for me was the FocusManager.FocusedElement attribute. I first tried to set it on the UserControl, but it didn't work.
So I tried putting it on the UserControl's first child instead:
<UserControl x:Class="WpfApplication3.UserControl1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Grid FocusManager.FocusedElement="{Binding ElementName=MyTextBox, Mode=OneWay}">
<TextBox x:Name="MyTextBox"/>
</Grid>
... and it worked! :)
I have user control - stack panel with two text boxes.The text boxes were added in contructor, not in the xaml. When i try to focus first text box, nothing happend.
The siggestion with Loaded event fix my problem. Just called control.Focus() in Loaded event and everthing.
Assuming you want to set focus for Username textbox, thus user can type in directly every time it shows up.
In Constructor of your control:
this.Loaded += (sender, e) => Keyboard.Focus(txtUsername);
After trying combinations of the suggestions above, I was able to reliably assign focus to a desired text box on a child UserControl with the following. Basically, give focus to the child control and have the child UserControl give focus to its TextBox. The TextBox's focus statement returned true by itself, however did not yield the desired result until the UserControl was given focus as well. I should also note that the UserControl was unable to request focus for itself and had to be given by the Window.
For brevity I left out registering the Loaded events on the Window and UserControl.
Window
private void OnWindowLoaded(object sender, RoutedEventArgs e)
{
ControlXYZ.Focus();
}
UserControl
private void OnControlLoaded(object sender, RoutedEventArgs e)
{
TextBoxXYZ.Focus();
}
I set it in the PageLoaded() or control loaded, but then I'm calling WCF async service and doing stuff that seems to lose the focus. I have to to set it at the end of all the stuff I do. That's fine and all, but sometimes I make changes to the code and then I forget that I'm also setting the cursor.
I had same problem with setting keyboard focus to canvas in WPF user control.
My solution
In XAML set element to Focusable="True"
In element_mousemove event create simple check:
if(!element.IsKeyBoardFocused)
element.Focus();
In my case it works fine.