在 WPF 中,是否有一个事件可用于确定 aTabControl
的选定选项卡何时更改?
我尝试过使用TabControl.SelectionChanged
,但是当孩子在选项卡中的选择发生变化时,它会被触发很多次。
在 WPF 中,是否有一个事件可用于确定 aTabControl
的选定选项卡何时更改?
我尝试过使用TabControl.SelectionChanged
,但是当孩子在选项卡中的选择发生变化时,它会被触发很多次。
我将它绑定在处理程序中以使其工作:
void TabControl_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
if (e.Source is TabControl)
{
//do work when tab is changed
}
}
如果将x:Name
属性设置为每个TabItem
:
<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>
然后您可以在活动中访问每个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
}
如果您只想在选择选项卡时有一个事件,这是正确的方法:
<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>
在你的代码中
private void OnTabSelected(object sender, RoutedEventArgs e)
{
var tab = sender as TabItem;
if (tab != null)
{
// this tab is selected!
}
}
您仍然可以使用该事件。只需检查 sender 参数是否是您真正关心的控件,如果是,则运行事件代码。
如果您使用的是 MVVM 模式,那么使用事件处理程序会很不方便(并且会破坏模式)。相反,您可以将每个单独的 TabItemSelector.IsSelected
属性绑定到视图模型中的依赖项属性,然后处理PropertyChanged
事件处理程序。这样,您就可以确切地知道基于 选择/取消选择了哪个选项卡,PropertyName
并且每个选项卡都有一个特殊的处理程序。
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
}
}
如果您的MainViewModel
isINotifyPropertyChanged
而不是DependencyObject
,请改用它:
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
}
}
生成的事件正在冒泡,直到它被处理。
下面的这个 xaml 部分在更改中选择的项目ui_Tab_Changed
后触发,无论.ui_A_Changed
ListView
TabItem
TabControl
<TabControl SelectionChanged="ui_Tab_Changed">
<TabItem>
<ListView SelectionChanged="ui_A_Changed" />
</TabItem>
<TabItem>
<ListView SelectionChanged="ui_B_Changed" />
</TabItem>
</TabControl>
我们需要在ui_A_Changed
(和ui_B_Changed
,等等)中消费事件:
private void ui_A_Changed(object sender, SelectionChangedEventArgs e) {
// do what you need to do
...
// then consume the event
e.Handled = true;
}
那是正确的事件。也许它没有正确接线?
<TabControl SelectionChanged="TabControl_SelectionChanged">
<TabItem Header="One"/>
<TabItem Header="2"/>
<TabItem Header="Three"/>
</TabControl>
在代码隐藏中......
private void TabControl_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
int i = 34;
}
如果我在 i = 34 行上设置断点,它只会在我更改选项卡时中断,即使选项卡有子元素并且其中一个被选中。
这段代码似乎工作:
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
}
}
如果有人使用 WPF Modern UI,他们不能使用 OnTabSelected 事件。但他们可以使用 SelectedSourceChanged 事件。
像这样
<mui:ModernTab Layout="Tab" SelectedSourceChanged="ModernTab_SelectedSourceChanged" Background="Blue" AllowDrop="True" Name="tabcontroller" >
C#代码是
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());
}
}