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