在WPF中,什么是Windows Forms中的Suspend/ResumeLayout()和BackgroundWorker()

Question

如果我在后面的代码中的函数中,并且我想在状态栏中实现显示"正在加载...",则以下内容是有意义的,但正如我们从WinForms中知道的那样是NoNo:

StatusBarMessageText.Text = "Loading Configuration Settings...";            
LoadSettingsGridData();
StatusBarMessageText.Text = "Done";

我们现在从WinForms第1章101类开始,在整个函数完成之前,表单不会显示对用户的更改...意味着"加载"消息将永远不会显示给用户.需要以下代码.

Form1.SuspendLayout();    
StatusBarMessageText.Text = "Loading Configuration Settings...";                
Form1.ResumeLayout();

LoadSettingsGridData();

Form1.SuspendLayout();    
StatusBarMessageText.Text = "Done";
Form1.ResumeLayout();

在WPF中处理这个基本问题的最佳做法是什么？

Answer 1

最简单的:

using(var d = Dispatcher.DisableProcessing())
{
    /* your work... Use dispacher.begininvoke... */
}

要么

IDisposable d;

try
{
    d = Dispatcher.DisableProcessing();
    /* your work... Use dispacher.begininvoke... */
} finally {
    d.Dispose();
}

Answer 2

实现此功能的最简单方法是将 LoadSettingsGridData 添加到调度程序队列。如果您将操作的 DispatcherPriority 设置得足够低，布局操作就会发生，您就可以开始了。

StatusBarMessageText.Text = "Loading Configuration Settings...";
this.Dispatcher.BeginInvoke(new Action(LoadSettingsGridData), DispatcherPriority.Render);
this.Dispatcher.BeginInvoke(new Action(() => StatusBarMessageText.Text = "Done"), DispatcherPriority.Render);