如何在Windows Phone 8中覆盖窗口后退按钮？

Question

当我从我的应用程序点击时,我需要将窗口后退按钮.我尝试了下面的方法,但它在Windows Phone 8中不起作用？

方法1)

protected override void OnBackKeyPress(System.ComponentModel.CancelEventArgs e)

            {

           e.Cancel = true;

           var result = MessageBox.Show("Do you want to exit?", "Attention!",
                                      MessageBoxButton.OKCancel);

        if (result == MessageBoxResult.OK)
        {
           // base.OnBackKeyPress(e);
            return;
        }
        e.Cancel = true;
    }

方法2)

a)在xaml标题中写道

BackKeyPress="MyBackKeyPress"

b)在构造函数中初始化它

 BackKeyPress += OnBackKeyPress;

c)并调用此方法

   private void MyBackKeyPress(object sender, System.ComponentModel.CancelEventArgs e)
    {
        e.Cancel = true; //tell system you have handled it
        //you c
    }

这两种方法都不起作用.当我点击后退按钮时,应用程序被破坏,无法控制后门按钮.有帮助吗？

Answer 1

根据认证要求,不建议覆盖后退按钮 -

从应用程序的第一个屏幕按"后退"按钮必须关闭该应用程序.

http://msdn.microsoft.com/en-us/library/windowsphone/develop/hh184840%28v=vs.105%29.aspx

您可以尝试此代码

protected override void OnBackKeyPress(CancelEventArgs e)
{
    if(MessageBox.Show("Are you sure you want to exit?","Confirm Exit?", 
                            MessageBoxButton.OKCancel) != MessageBoxResult.OK)
    {
        e.Cancel = true; 

    }
}