void window_Closing(object sender, CancelEventArgs e)
{
// 如果是 NavOut 导致的关闭，则不作任何处理，直接关闭，不会触发 WannaClose 事件
// 否则认为是用户点击右上角的关闭按钮，发出 WannaClose 通知交由外部处理
bool userClickCloseButton = !WindowAddtionInfo.GetCloseBecauseNavOut(window);
if (userClickCloseButton)
{
if (WannaClose != null)
{
WindowAddtionInfo.SetAcceptClose(window, false);
WindowAddtionInfo.SetInClosingCallStack(window, true);
try
{
WannaClose(this, EventArgs.Empty);
}
finally
{
WindowAddtionInfo.SetInClosingCallStack(window, false);
}
}
e.Cancel = !WindowAddtionInfo.GetAcceptClose(window);
}
}
public void NavOut()
{
// 如果根本就没有任何窗体，则忽略本次调用
if (window == null)
{
return;
}
// 子类将重写 beforeNavOut() 以完成窗体的初始化等工作
beforeNavOut();
// 执行关闭窗口的操作
if (WindowAddtionInfo.GetInClosingCallStack(window))
{
// 当前调用是位于 Closing 调用栈里
// 我们只需把相关字段设为 true 就可以完成关闭
// 不能去调用 Close() 方法，否则会抛出异常
WindowAddtionInfo.SetAcceptClose(window, true);
}
else
{
// 直接调用 Close() 就可以关闭窗口了
// 为了避免事件重复触发，这里需要在 Close() 前做个标记
WindowAddtionInfo.SetCloseBecauseNavOut(window, true);
window.Close();
}
}
static public bool GetInClosingCallStack(Window window)
{
WindowAddtionInfo info = null;
info = window.Tag as WindowAddtionInfo;
return(info != null ? info.InClosingCallStack : false);
}
static public bool GetAcceptClose(Window window)
{
WindowAddtionInfo info = null;
info = window.Tag as WindowAddtionInfo;
return(info != null ? info.AcceptClose : false);
}
static public bool GetCloseBecauseNavOut(Window window)
{
WindowAddtionInfo info = null;
info = window.Tag as WindowAddtionInfo;
return(info != null ? info.CloseBecauseNavOut : false);
}
static private WindowAddtionInfo retriveOrCreateInfo(Window window)
{
if (window.Tag != null && window.Tag as WindowAddtionInfo == null)
{
throw new InvalidOperationException();
}
WindowAddtionInfo info = window.Tag as WindowAddtionInfo;
if (info == null)
{
window.Tag = info = new WindowAddtionInfo();
}
return(info);
}
