WPF中UI线程更新
WPF中UI线程更新
2011-11-11 16:11
WPF中UI线程队列由Dispatcher来管理和调度,所以当用户线程中更新UI时,必须通过Dispatche来调度,下面这个小例子将给用户展示如何在用户线程中更新当前的时间.
前台的XAML代码如下:
<Windowx:Class="ThreadInvoke.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="ThreadInvoke"Height="300"Width="300"
>
<StackPanelOrientation="Vertical">
<StackPanelOrientation="Horizontal">
<ButtonContent="Ok"Click="okClick"Width="50"/>
<ButtonContent="Stop"Click="stopClick"Width="50"/>
</StackPanel>
<TextBoxName="timeText"></TextBox>
</StackPanel>
</Window>
后台的主要代码如下:
//申明一个代理用于想UI更新时间
privatedelegatevoidDelegateSetCurrentTime();
//申明一个变量,用于停止时间的跳动
privatebool stopFlag = false;
//处理开始和结束事件
privatevoid okClick(object sender,RoutedEventArgs args)
{
stopFlag = false;
Thread thread = newThread(newThreadStart(refreshTime));
thread.Start();
}
privatevoid stopClick(object sender, RoutedEventArgs args)
{
stopFlag = true;
}
//用户线程的实现函数
privatevoid refreshTime()
{
while (!stopFlag)
{
//向UI界面更新时钟显示 Dispatcher.Invoke(System.Windows.Threading.DispatcherPriority.SystemIdle, newDelegateSetCurrentTime(setCurrentTime));
}
}
privatevoid setCurrentTime()
{
String currentTime = System.DateTime.Now.ToString();
timeText.Text = currentTime;
}
2007-1-8 Paul.Peng