commandbinding

问题 Im deriving from a third party control. It is implementing ApplicationCommands.SelectAll. However the behaviour i want is slightly different. there is no virtual method i can override, and when i register a class handler, like so CommandManager.RegisterClassCommandBinding(typeof(MyDerivedControl), new CommandBinding(ApplicationCommands.SelectAll, new ExecutedRoutedEventHandler(OnExecutedSelectAll), new CanExecuteRoutedEventHandler(OnCanExecuteSelectAll))); My methods do not get called. The

问题 How can I access the datacontext of the parent element in windows phone 8? AncestorType is not available in WP8. <ItemsControl x:Name="Elements" ItemsSource="{Binding MyList}" Grid.Row="2" Grid.Column="3"> <ItemsControl.ItemsPanel> <ItemsPanelTemplate> <toolkit:WrapPanel /> </ItemsPanelTemplate> </ItemsControl.ItemsPanel> <ItemsControl.ItemTemplate> <DataTemplate> <Button Content="e" Width="100" Height="100" Command="{Binding MyCommand" /> </DataTemplate> </ItemsControl.ItemTemplate> <

问题 How can I bind a UserControl 's FrameworkElement event to a view model command? I use MVVM and Prism so clear separation between the view the view-model would be nice. I'd tried multiple things, and none of them worked: <i:Interaction.Triggers> <i:EventTrigger EventName="FrameworkElement.Unloaded"> <i:InvokeCommandAction Command="{Binding Unloaded}" /> </i:EventTrigger> </i:Interaction.Triggers> also using this tutorial http://blog.functionalfun.net/2008/09/hooking-up-commands-to-events-in

问题 I have a custom Button as follows: <UserControl...> <Button HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch"> <Grid> <Grid.ColumnDefinitions> <ColumnDefinition Width="3*"/> <ColumnDefinition Width="*"/> </Grid.ColumnDefinitions> <Viewbox Stretch="Uniform" Grid.Column="0"> <TextBlock x:Name="numCopyTB" Text="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type UserControl}}, Path=Text}"/> </Viewbox> <Viewbox Grid.Column="1"> <TextBlock Style="

问题 I need to implement a custom copy + cut + paste for data (not text or CSV) to be copied between grids in a WPF application. Using standard ApplicationCommands and defining CommandBinding works really well but only if the DataGrid contains at least 1 row of data and when it's selected. When there are no rows or focus is not on any of them, all commands are disabled. To fix the problem I tried calling CommandManager.InvalidateRequerySuggested() and setting Focusable=true and/or FocusManager

问题 For Command "CommandZoomIn", CanExecute and Execute do not occurs for controls defined into the ListBox ItemTemplate. GraphLcView method "CanExecute" and "Execute" are both called when GraphLcView UserControl is defined directly as child of AnalysisView, but both methods are never called when they are added as Item DataTemplate of a ListBox ItemTemplate. The button with the command is defined in my top level window into a Ribbon. Simplified hierarchy: (Working) Top Level window ->

问题 Snoop shows that the command is "ApplySingleSpace", but when I try disabling it via the method described in this article . Like this: <RichTextBox.CommandBindings> <CommandBinding Command="ApplySingleSpace" CanExecute="BlockTheCommand"/> </RichTextBox.CommandBindings> . private void BlockTheCommand(object sender, CanExecuteRoutedEventArgs e) { e.CanExecute = false; e.Handled = true; } My app crashes because there is no ApplySingleSpace command. ApplySingleSpace is not in the EditingCommands

问题 I have a button on a view that is bound via a RoutedUICommand to a command defined in the ViewModel. The XAML code excerpt from the view: <Button Content="Login" Command="{Binding Login}" /> In the View's CodeBehind I add the command binding from the ViewModel to the view's binding collection: this.CommandBindings.Add( viewModel.LoginCommandBinding ); The ViewModel itself implements the command: public class LoginViewModel:ViewModelBase { public ICommand Login { get; private set; } public

问题 I have a button on a view that is bound via a RoutedUICommand to a command defined in the ViewModel. The XAML code excerpt from the view: <Button Content="Login" Command="{Binding Login}" /> In the View's CodeBehind I add the command binding from the ViewModel to the view's binding collection: this.CommandBindings.Add( viewModel.LoginCommandBinding ); The ViewModel itself implements the command: public class LoginViewModel:ViewModelBase { public ICommand Login { get; private set; } public

问题 I'm having some trouble understanding how command parameter binding works. When I create an instance of the widget class before the call to InitializeComponent it seems to work fine. Modifications to the parameter(Widget) in the ExecuteCommand function will be "applied" to _widget. This is the behavior I expected. If the instance of _widget is created after InitializeComponent, I get null reference exceptions for e.Parameter in the ExecuteCommand function. Why is this? How do I make this work