標準WPF選項卡控件中是否存在「選定選項卡已更改事件」

Question

在WPF中，是否存在可用於確定TabControl選定選項卡更改時間的事件？

我嘗試過使用TabControl.SelectionChanged，但是當標籤中的孩子的選擇發生變化時，它會被多次觸發。

Answer 1

我在處理此掛鉤，使其工作：

void TabControl_SelectionChanged(object sender, SelectionChangedEventArgs e) 
{ 
    if (e.Source is TabControl) 
    { 
     //do work when tab is changed 
    } 
} 

Answer 2

您仍然可以使用該事件。只需檢查發件人參數是否是您真正關心的控件，如果是，請運行事件代碼。

Answer 3

這是正確的事件。也許它沒有正確連接？

<TabControl SelectionChanged="TabControl_SelectionChanged"> 
    <TabItem Header="One"/> 
    <TabItem Header="2"/> 
    <TabItem Header="Three"/> 
</TabControl> 

在代碼隱藏

....

private void TabControl_SelectionChanged(object sender, SelectionChangedEventArgs e) 
{ 
    int i = 34; 
} 

如果我設置了I = 34行設置一個斷點，它只有當我更改選項卡斷，即使標籤子元素和一個他們被選中。

Answer 4

生成的事件冒泡，直到它被處理。

下面此XAML部觸發ui_Tab_Changedui_A_Changed後當在TabControl在ListView變化選擇，無論TabItem變化的項。

<TabControl SelectionChanged="ui_Tab_Changed"> 
    <TabItem> 
    <ListView SelectionChanged="ui_A_Changed" /> 
    </TabItem> 
    <TabItem> 
    <ListView SelectionChanged="ui_B_Changed" /> 
    </TabItem> 
</TabControl> 

我們需要消耗事件ui_A_Changed（和ui_B_Changed，等等）：如果你的x:Name屬性設置爲每個TabItem作爲

private void ui_A_Changed(object sender, SelectionChangedEventArgs e) { 
    // do what you need to do 
    ... 
    // then consume the event 
    e.Handled = true; 
} 

Answer 5

：

<TabControl x:Name="MyTab" SelectionChanged="TabControl_SelectionChanged"> 
    <TabItem x:Name="MyTabItem1" Header="One"/> 
    <TabItem x:Name="MyTabItem2" Header="2"/> 
    <TabItem x:Name="MyTabItem3" Header="Three"/> 
</TabControl> 

然後您可以在事件中訪問每個TabItem：

private void TabControl_SelectionChanged(object sender, SelectionChangedEventArgs e) 
{ 
    if (MyTabItem1.IsSelected) 
    // do your stuff 
    if (MyTabItem2.IsSelected) 
    // do your stuff 
    if (MyTabItem3.IsSelected) 
    // do your stuff 
} 

Answer 6

此代碼似乎工作：

private void TabControl_SelectionChanged(object sender, SelectionChangedEventArgs e) 
    { 
     TabItem selectedTab = e.AddedItems[0] as TabItem; // Gets selected tab 

     if (selectedTab.Name == "Tab1") 
     { 
      // Do work Tab1 
     } 
     else if (selectedTab.Name == "Tab2") 
     { 
      // Do work Tab2 
     } 
    } 

Answer 7

如果你只是想有一個事件當選擇一個標籤，這是正確的做法：

<TabControl> 
    <TabItem Selector.Selected="OnTabSelected" /> 
    <TabItem Selector.Selected="OnTabSelected" /> 
    <TabItem Selector.Selected="OnTabSelected" /> 
    <!-- You can also catch the unselected event --> 
    <TabItem Selector.Unselected="OnTabUnSelected" /> 
</TabControl> 

並在代碼

private void OnTabSelected(object sender, RoutedEventArgs e) 
    { 
     var tab = sender as TabItem; 
     if (tab != null) 
     { 
      // this tab is selected! 
     } 
    } 

Answer 8

如果有人使用WPF現代用戶界面，他們不能使用OnTabSelected事件，但他們可以使用SelectedSourceChanged事件。

這樣

<mui:ModernTab Layout="Tab" SelectedSourceChanged="ModernTab_SelectedSourceChanged" Background="Blue" AllowDrop="True" Name="tabcontroller" > 

C＃代碼是

private void ModernTab_SelectedSourceChanged(object sender, SourceEventArgs e) 
    { 
      var links = ((ModernTab)sender).Links; 

      var link = this.tabcontroller.Links.FirstOrDefault(l => l.Source == e.Source); 

      if (link != null) { 
       var index = this.tabcontroller.Links.IndexOf(link); 
       MessageBox.Show(index.ToString()); 
      }    
    } 

Answer 9

如果你使用MVVM模式則是不方便的（並打破模式）使用事件處理程序。相反，您可以將每個單獨的TabItem的Selector.IsSelected屬性綁定到viewmodel中的依賴項屬性，然後處理PropertyChanged事件處理程序。通過這種方式，您可以確切知道基於PropertyName選擇/取消選擇哪個選項卡，並且每個選項卡都有一個特殊處理程序。

例子：MainView.xaml

<TabControl> 
<TabItem Header="My tab 1" Selector.IsSelected="{Binding IsMyTab1Selected}"> ... </TabItem> 
<TabItem Header="My tab 2" Selector.IsSelected="{Binding IsMyTab2Selected}"> ... </TabItem> 
</TabControl> 

例子：MainViewModel.cs

public bool IsMyTab1Selected { 
get { return (bool)GetValue(IsMyTab1SelectedProperty); } 
set { SetValue(IsMyTab1SelectedProperty, value); } 
} 
public static readonly DependencyProperty IsMyTab1SelectedProperty = 
DependencyProperty.Register("IsMyTab1Selected", typeof(bool), typeof(MainViewModel), new PropertyMetadata(true, new PropertyChangedCallback(MyPropertyChanged))); 

public bool IsMyTab2Selected { 
get { return (bool)GetValue(IsMyTab2SelectedProperty); } 
set { SetValue(IsMyTab2SelectedProperty, value); } 
} 
public static readonly DependencyProperty IsMyTab2SelectedProperty = 
DependencyProperty.Register("IsMyTab2Selected", typeof(bool), typeof(MainViewModel), new PropertyMetadata(false, new PropertyChangedCallback(MyPropertyChanged))); 

private void MyPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) { 
if (e.Property.Name == "IsMyTab1Selected") { 
    // stuff to do 
} else if (e.Property.Name == "IsMyTab2Selected") { 
    // stuff to do 
} 
} 

如果您MainViewModel是INotifyPropertyChanged而非DependencyObject，然後用這個來代替：

例子：MainViewModel.cs

public event PropertyChangedEventHandler PropertyChanged; 
protected virtual void OnPropertyChanged(string propertyName) { 
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName)); 
} 

public MainViewModel() { 
PropertyChanged += handlePropertyChanged; 
} 

public bool IsMyTab1Selected { 
get { return _IsMyTab1Selected ; } 
set { 
    if (value != _IsMyTab1Selected) { 
    _IsMyTab1Selected = value; 
    OnPropertyChanged("IsMyTab1Selected "); 
    } 
} 
} 
private bool _IsMyTab1Selected = false; 

public bool IsMyTab2Selected { 
get { return _IsMyTab2Selected ; } 
set { 
    if (value != _IsMyTab2Selected) { 
    _IsMyTab2Selected = value; 
    OnPropertyChanged("IsMyTab2Selected "); 
    } 
} 
} 
private bool _IsMyTab2Selected = false; 

private void handlePropertyChanged(object sender, PropertyChangedEventArgs e) { 
if (e.PropertyName == "IsMyTab1Selected") { 
    // stuff to do 
} else if (e.PropertyName == "IsMyTab2Selected") { 
    // stuff to do 
} 
}