windows phone Fast Resume 快速恢复

转自：WP8点击桌面图标快速恢复应用

如何实现在WindowsPhone8 应用程序中 点击了 Windows logo 后 重新在应用程序列表中单击该程序图标 快速启动应用程序
示例代码 下载
1. 在App.cs 文件中修改添加一下代码

#region 电话应用程序初始化

// 避免双重初始化
private bool phoneApplicationInitialized = false;

// 请勿向此方法中添加任何其他代码
private void InitializePhoneApplication()
{
if (phoneApplicationInitialized)
return;

// 创建框架但先不将它设置为 RootVisual；这允许初始
// 屏幕保持活动状态，直到准备呈现应用程序时。
RootFrame = new PhoneApplicationFrame();
RootFrame.NavigationFailed += RootFrame_NavigationFailed;

RootFrame.NavigationFailed += RootFrame_NavigationFailed;

RootFrame.Navigated += CompleteInitializePhoneApplication;
RootFrame.Navigated += CheckForResetNavigation;

RootFrame.Navigating += RootFrame_Navigating;

// 确保我们未再次初始化
phoneApplicationInitialized = true;
}

bool isReset = false;
void RootFrame_Navigating(object sender, NavigatingCancelEventArgs e)
{
//Resest验证判断 (此处会执行两次)
if (e.NavigationMode == NavigationMode.Reset)
{
isReset = true;
}
else if (e.NavigationMode == NavigationMode.New && isReset)
{
isReset = false;
e.Cancel = true; // 取消导航到新页面s
RootFrame.Navigated -= ClearBackStackAfterReset; // 取消导航完成事件(否则会直接退出程序)
}
}

void CompleteInitializePhoneApplication(object sender, NavigationEventArgs e)
{
if (RootVisual != RootFrame)
RootVisual = RootFrame;
RootFrame.Navigated -= CompleteInitializePhoneApplication;
}

void CheckForResetNavigation(object sender, NavigationEventArgs e)
{
if (e.NavigationMode == NavigationMode.Reset)
RootFrame.Navigated += ClearBackStackAfterReset;
}
private void ClearBackStackAfterReset(object sender, NavigationEventArgs e)
{
RootFrame.Navigated -= ClearBackStackAfterReset;

if (e.NavigationMode != NavigationMode.New)
return;

while (RootFrame.RemoveBackEntry() != null)
{
;
}
}

#endregion

2.在WMAppManifest.xml 中添加 ActivationPolicy="Resume"

<Tasks>
<DefaultTask Name="_default" NavigationPage="MainPage.xaml" ActivationPolicy="Resume"/>
</Tasks>