Let's say I got the following ComboBox in my XAML:
<ComboBox x:Name="cmbOinkOink" Loaded="cmbOinkOink_Loaded" />
And I have my cmbOinkOink_Loaded method deep in here:
namespace PiggyWPF.Classes.EventHandler
{
class ComboBoxEventHandler
{
public void cmbOinkOink_Loaded(object sender, RoutedEventArgs e)
{
// Do Stuff...
}
}
}
How am I going to tell XAML that the cmbOinkOink_Loaded is going to be found under PiggyWPF.Classes.EventHandler.ComboBoxEventHandler?
I am not sure there is a straight forward way to achieve this behavior from xaml.
but you can do this easily from code behind.
class Control
{
...
public void cmbOinkOink_Loaded(object sender, RoutedEventArgs e)
{
_handlerObject.DoStuff();
}
You will have to forward the method call one way or another, either via the code behind of that XAML that defines the ComboBox or by using e.g. the ExecuteCommandAction from Interactivity, which requires you to provide a command in you original class instead of just a method, ideally static or otherwise easily accessible so you can use x:Static or something similar in the action's XAML.
(Posted on behalf of the OP).
I guess my only way was to add the following code to my main class:
private void cmbOinkOink_Loaded(object sender, RoutedEventArgs e)
{
using (ComboBoxEventHandler cmbEvent = new ComboBoxEventHandler())
{
cmbEvent.cmbOinkOink_Loaded(ref sender, e);
}
}
Related
I am using MahApps.metro WPF library with MVVM. I have a ViewModel from which I need to display a Dialog. The MetroWindow has ShowMessageAsync. But what is the proper way to access it from the ViewModel? As I understand I need a View instance but passing that into the ViewModel doesn't seem like a good approach.
Use following approach:
Take an Action<T> ShowMessageAsync in your ViewModel which you are binding with window.
Now create a behaviour for Window and use following code in behaviour
protected override void OnAttached()
{
base.OnAttached();
this.AssociatedObject.Loaded += AssociatedObject_Loaded;
}
void AssociatedObject_Loaded(object sender, RoutedEventArgs e)
{
if (this.AssociatedObject.DataContext is WindowViewModel)
{
WindowViewModel vm = this.AssociatedObject.DataContext as WindowViewModel;
vm.ShowMessageAsync = OnShowMessageAsync;
}
}
private void OnShowMessageAsync(T param)
{
//Write your logic to call ShowMessageAsync method.
}
Now in this way, from the ViewModel of your MainWindow you will have ability to open another child window.
I'm newbie in Silverlight and I need to activate MouseRightButtonDown(object sender, MouseButtonEventArgs e) from an another event handler in my application.
I have found, that in WPF it is possible to do somthing like this:
public void OnContextMenuOpened(object sender, RoutedEventArgs e) {
MouseButtonEventArgs args = new MouseButtonEventArgs(
InputManager.Current.PrimaryMouseDevice,
0,
MouseButton.Right);
MouseRightButtonDown(sender, args);
}
But I have in Silverlight neither InputManager-Class nor MouseButton-Class... It is generally possible to realise something like that?
I want to do it, because I try to select an DataGridRow(within an custom control) with help of right-mouse-button. Without context menu it is easily possible, but when I switch context menu on, then context menu opens and event will not fired...
My code snippet:
public override void OnApplyTemplate() {
DataGrid = (DataGrid)GetTemplateChild("DataGrid");
DataGrid.MouseRightButtonDown += DataGridMouseRightButtonDown;
ContextMenu = (ContextMenu)GetTemplateChild("ContextMenu");
ContextMenu.Opened += OnContextMenuOpened;
}
private void DataGridMouseRightButtonDown(object sender, MouseButtonEventArgs e) {
//My code to select an DataGridRow
}
public void OnContextMenuOpened(object sender, RoutedEventArgs e) {
//This event-handler now will be always activated if I do
//right-mouse-button-click
}
Thanks a lot for help!
The Results of my research has shown, that it is impossible in silverlight -.-
neither
<WebBrowser x:Name="wbMain" Cursor="None"></WebBrowser>
nor
*{cursor:none}
is working for me. I can't find any resources online telling me how to accomplish this. The use-case for this is an application that runs full screen meant for viewing only after the setup takes place.
Edit: I forgot to add that the css works as expected when viewing the website in the IE9 browser.
I don't know if this is a good or bad practice but you can add System.Windows.Forms reference
then
private void MouseEnter(object sender, MouseEventArgs e)
{
System.Windows.Forms.Cursor.Hide();
}
private void MouseLeave(object sender, MouseEventArgs e)
{
System.Windows.Forms.Cursor.Show();
}
use this code on mouseEnter form example in web-browser control
For those who dont like to add WinForms reference, try
[DllImport("user32.dll")]
static extern int ShowCursor(bool bShow);
and call ShowCursor(false) when needed.
In app.cs
protected override void OnStartup(StartupEventArgs e)
{
System.Windows.Forms.Cursor.Hide();
}
Thanks to this question (click me!), I have the Source property of my WebBrowser binding correctly to my ViewModel.
Now I'd like to achieve two more goals:
Get the IsEnabled property of my Back and Forward buttons to correctly bind to the CanGoBack and CanGoForward properties of the WebBrowser.
Figure out how to call the GoForward() and GoBack() methods without resorting to the code-behind and without the ViewModel having to know about the WebBrowser.
I have the following (non-working) XAML markup at the moment:
<WebBrowser
x:Name="_instructionsWebBrowser"
x:FieldModifier="private"
clwm:WebBrowserUtility.AttachedSource="{Binding InstructionsSource}" />
<Button
Style="{StaticResource Button_Style}"
Grid.Column="2"
IsEnabled="{Binding ElementName=_instructionsWebBrowser, Path=CanGoBack}"
Command="{Binding GoBackCommand}"
Content="< Back" />
<Button
Style="{StaticResource Button_Style}"
Grid.Column="4"
IsEnabled="{Binding ElementName=_instructionsWebBrowser, Path=CanGoForward}"
Command="{Binding GoForwardCommand}"
Content="Forward >" />
I'm pretty sure the problem is that CanGoBack and CanGoForward are not dependency properties (and don't implement INotifyChanged), but I'm not quite sure how to get around that.
Questions:
Is there any way to hook up attached properties (as I did with Source) or something similar to get the CanGoBack and CanGoForward bindings to work?
How do write the GoBackCommand and GoForwardCommand so they are independent of the code-behind and ViewModel and can be declared in markup?
For anyone who comes across this question and wants a complete solution, here it is. It combines all of the suggestions made in this thread and the linked threads (and others those link to).
XAML:
http://pastebin.com/aED9pvW8
C# class:
http://pastebin.com/n6cW9ZBB
Example XAML usage:
http://pastebin.com/JpuNrFq8
Note: The example assumes your view binds to a ViewModel that provides the source URL to the browser. A very rudimentary navigation bar with back, forward, and refresh buttons and address bar is provided just for demonstration.
Enjoy. I have set the expiration on those pastebin's to never, so they should be available for as long as pastebin exists.
I used this in my bindable webbrowser wrapper:
CommandBindings.Add(new CommandBinding(NavigationCommands.BrowseBack, BrowseBack, CanBrowseBack));
CommandBindings.Add(new CommandBinding(NavigationCommands.BrowseForward, BrowseForward, CanBrowseForward));
CommandBindings.Add(new CommandBinding(NavigationCommands.BrowseHome, GoHome, TrueCanExecute));
CommandBindings.Add(new CommandBinding(NavigationCommands.Refresh, Refresh, TrueCanExecute));
CommandBindings.Add(new CommandBinding(NavigationCommands.BrowseStop, Stop, TrueCanExecute));
Note that I created my bindable webbrowser as FrameworkElement that exposes DependencyProperties and calls methods on the actual browser element, so i can set CommandBindings on it.
That way, you can use the default NavigationCommands in your View.
The used handlers are:
private void CanBrowseBack(object sender, CanExecuteRoutedEventArgs e) {
e.CanExecute = webBrowser.CanGoBack;
}
private void BrowseBack(object sender, ExecutedRoutedEventArgs e) {
webBrowser.GoBack();
}
private void CanBrowseForward(object sender, CanExecuteRoutedEventArgs e) {
e.CanExecute = webBrowser.CanGoForward;
}
private void BrowseForward(object sender, ExecutedRoutedEventArgs e) {
webBrowser.GoForward();
}
private void TrueCanExecute(object sender, CanExecuteRoutedEventArgs e) { e.CanExecute = true; }
private void Refresh(object sender, ExecutedRoutedEventArgs e) {
try { webBrowser.Refresh(); }
catch (Exception ex) { PmsLog.LogException(ex, true); }
}
private void Stop(object sender, ExecutedRoutedEventArgs e) {
mshtml.IHTMLDocument2 doc = WebBrowser.Document as mshtml.IHTMLDocument2;
if (doc != null)
doc.execCommand("Stop", true, null);
}
private void GoHome(object sender, ExecutedRoutedEventArgs e) {
Source = new Uri(Home);
}
Your question seems to imply that in order to correctly implement an MVVM pattern you are not allowed to have any code-behind. But perhaps adding some code-behind to your view will make it much easier to hook it up with your view-model. You can add dependency properties to the view and let it listen for INotifyPropertyChanged events.
Is it possible to bind the multiple commands to the button.
I have a user control, which i am calling in my main application (parent application).
I want to handle a click command on both the controls (the user control as well as on the main window). However i am only able to get one.
Is there any way in which i can get this.
Any help is really appreciated.
Code Snippet:
public class MainWindowFooterCommands
{
public static readonly RoutedUICommand FooterClickLocalCommand = new RoutedUICommand("Local Button Command", "FooterClickLocalCommand", typeof(MainWindowFooterCommands));
}
private void MainWindowFooterBindCommands()
{
CommandBinding cmdBindingBXClick = new CommandBinding(MainWindowFooterCommands.FooterClickLocalCommand);
cmdBindingBXClick.Executed += ClickCommandHandler;
CommandBindings.Add(cmdBindingBXClick);
}
void ClickCommandHandler(object sender, ExecutedRoutedEventArgs e)
{
//Do Something
}
//Parent Control holding an instance of the footer control.
class MainWindow {
public MainWindow()
{
CommandBinding cmdBindingBXClick1 = new CommandBinding(MainWindowFooterCommands.BXClickMainWindowCommand);
cmdBindingBXClick1.Executed += LoadParent;
CommandBindings.Add(cmdBindingBXClick1);
}
public void LoadParent(object sender, ExecutedRoutedEventArgs e)
{
LoadParentWindow();
}
}
Regards,
Tushar
You might be trying to aggregate multiple commands, which is a natural thing to want to do.
If you are using Prism, there is a class builtin for this called the CompositeCommand (scroll down a bit): https://msdn.microsoft.com/en-us/library/ff921126.aspx
Otherwise, Josh Smith has a very good article on his implementation called a "Command Group": http://www.codeproject.com/KB/WPF/commandgroup.aspx
There are some very nice scenarios you can rollup like this (for instance, "Save All"). A good tool for your bag of tricks.
AFAIK WPF doesnt offer anything out of the box to support multiple commandbindings at various levels, but you could try the following:
void ClickCommandHandler(object sender, ExecutedRoutedEventArgs e)
{
IInputElement parent = (IInputElement) LogicalTreeHelper.GetParent((DependencyObject)sender);
MainWindowFooterCommands.BXClickMainWindowCommand.Execute(e.Parameter, parent);
}
You might have to test whether your parent really is an IInputElement, though.