Bind command to Loaded event of view

问题

I am trying to get a method to run when a view has finished loading. I have tried to bind a command to the Loaded event in the view but it fails to run. The inner exception that is thrown is

'Provide value on 'System.Windows.Data.Binding' threw an exception.' Line number '14' and line position '14'

<UserControl x:Class="Components.Map.MapView"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:map="clr-namespace:Components.Map"
             xmlns:controls="clr-namespace:Windows.Controls;assembly=Windows.Controls"
             xmlns:ValidationRules="clr-namespace:Windows.Controls.ValidationRules;assembly=Windows.Controls"
             xmlns:directGraphicsControl="clr-namespace:Windows.DirectGraphicsControl;assembly=Windows.DirectGraphicsControl"
             xmlns:colorBar="clr-namespace:Components.Common.ColorBar;assembly=Components.Common"
             xmlns:RefinedRibbonControls="clr-namespace:Components.Common.Controls.RefinedRibbonControls;assembly=Components.Common"
             xmlns:UserControls="clr-namespace:Components.Common.UserControls;assembly=Components.Common"
             xmlns:map1="clr-namespace:Models.Map;assembly=Models.Map"
             xmlns:utilities="clr-namespace:Windows.Utilities;assembly=Windows.Utilities"
             xmlns:system="clr-namespace:System;assembly=mscorlib"
             Loaded="{Binding Path=MapControlViewModel.MapLoadedCommand}">

How am I able to bind to a view’s Loaded event so I can run something after the view has finished loading?

回答1:

If you want to bind command to the Loaded event, you should use the "System.Windows.Interactivity" assembly.

<UserControl x:Class="Components.Map.MapView"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:map="clr-namespace:Components.Map"
             xmlns:controls="clr-namespace:Windows.Controls;assembly=Windows.Controls"
             xmlns:ValidationRules="clr-namespace:Windows.Controls.ValidationRules;assembly=Windows.Controls"
             xmlns:directGraphicsControl="clr-namespace:Windows.DirectGraphicsControl;assembly=Windows.DirectGraphicsControl"
             xmlns:colorBar="clr-namespace:Components.Common.ColorBar;assembly=Components.Common"
             xmlns:RefinedRibbonControls="clr-namespace:Components.Common.Controls.RefinedRibbonControls;assembly=Components.Common"
             xmlns:UserControls="clr-namespace:Components.Common.UserControls;assembly=Components.Common"
             xmlns:map1="clr-namespace:Models.Map;assembly=Models.Map"
             xmlns:utilities="clr-namespace:Windows.Utilities;assembly=Windows.Utilities"
             xmlns:system="clr-namespace:System;assembly=mscorlib"
             xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity">

             <i:Interaction.Triggers>
                <i:EventTrigger EventName="Loaded">
                    <i:InvokeCommandAction Command="{Binding LoadedCommand}" />
                </i:EventTrigger>
            </i:Interaction.Triggers>

</UserControl>

System.Windows.Interactivity.dll is in Microsoft Expression Blend Software Development Kit (SDK) (download link) and also available as a NuGet package.

来源：https://stackoverflow.com/questions/17933102/bind-command-to-loaded-event-of-view

标签

wpf

xaml

commandbinding