public void Activate(CachedFileUpdaterActivatedEventArgs args)
{
// cache CachedFileUpdaterUI
cachedFileUpdaterUI = args.CachedFileUpdaterUI;
cachedFileUpdaterUI.FileUpdateRequested += CachedFileUpdaterUI_FileUpdateRequested;
cachedFileUpdaterUI.UIRequested += CachedFileUpdaterUI_UIRequested;
switch (cachedFileUpdaterUI.UpdateTarget)
{
case CachedFileTarget.Local:
scenarios = new List <Scenario> {
new Scenario()
{
Title = "Get latest version", ClassType = typeof(FilePickerContracts.CachedFileUpdater_Local)
}
};
break;
case CachedFileTarget.Remote:
scenarios = new List <Scenario> {
new Scenario()
{
Title = "Remote file update", ClassType = typeof(FilePickerContracts.CachedFileUpdater_Remote)
}
};
break;
}
Window.Current.Activate();
}
private async void OnUIRequested(CachedFileUpdaterUI sender, object args)
{
// The event handler may be invoked on a background thread, so use the Dispatcher to run the UI-related code on the UI thread.
await Window.Current.Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () =>
{
});
}
void CachedFileUpdaterUI_FileUpdateRequested(CachedFileUpdaterUI sender, FileUpdateRequestedEventArgs args)
{
fileUpdateRequest = args.Request;
fileUpdateRequestDeferral = fileUpdateRequest.GetDeferral();
switch (cachedFileUpdaterUI.UIStatus)
{
case UIStatus.Hidden:
if (fileUpdateRequest.File.Name.Contains("ConflictingFile"))
{
fileUpdateRequest.Status = FileUpdateStatus.UserInputNeeded;
}
else
{
fileUpdateRequest.Status = FileUpdateStatus.Complete;
}
fileUpdateRequestDeferral.Complete();
break;
case UIStatus.Visible:
break;
case UIStatus.Unavailable:
fileUpdateRequest.Status = FileUpdateStatus.Failed;
fileUpdateRequestDeferral.Complete();
break;
}
}
public void Activate(CachedFileUpdaterActivatedEventArgs args)
{
// cache CachedFileUpdaterUI
cachedFileUpdaterUI = args.CachedFileUpdaterUI;
// Currently, the Desktop device family activates the app in the background. Other device families
// use a background task activation. We need to handle both cases.
//
// We can check to see if there is UI on activation to determine which case we are in, because
// we receive the FileUpdateRequest differently.
//
// If activated in the foreground (visible), then the FileUpdateRequest is passed explicitly as
// part of the activation.
//
// If activated in the background (not visible), then we subscribe to the FileUpdateRequested
// and UIRequest events. The FileUpdateRequest is received as part of the FileUpdatedRequested event,
// and UIRequested is raised when user input is needed to resolve a conflict.
bool isForegroundActivated = (cachedFileUpdaterUI.UIStatus == UIStatus.Visible);
if (isForegroundActivated)
{
fileUpdateRequest = cachedFileUpdaterUI.UpdateRequest;
fileUpdateRequestDeferral = cachedFileUpdaterUI.GetDeferral();
}
else
{
cachedFileUpdaterUI.FileUpdateRequested += CachedFileUpdaterUI_FileUpdateRequested;
cachedFileUpdaterUI.UIRequested += CachedFileUpdaterUI_UIRequested;
}
switch (cachedFileUpdaterUI.UpdateTarget)
{
case CachedFileTarget.Local:
scenarios = new List <Scenario> {
new Scenario()
{
Title = "Get latest version", ClassType = typeof(FilePickerContracts.CachedFileUpdater_Local)
}
};
break;
case CachedFileTarget.Remote:
scenarios = new List <Scenario> {
new Scenario()
{
Title = "Remote file update", ClassType = typeof(FilePickerContracts.CachedFileUpdater_Remote)
}
};
break;
}
if (isForegroundActivated)
{
Window.Current.Content = this;
this.OnNavigatedTo(null);
Window.Current.Activate();
}
}
// 需要显示 CachedFileUpdater 的 UI 时（即当 FileUpdateRequest.Status 等于 UserInputNeeded 时），会调用此事件处理器
async void _cachedFileUpdaterUI_UIRequested(CachedFileUpdaterUI sender, object args)
{
await _dispatcher.RunAsync(CoreDispatcherPriority.Normal, () =>
{
Windows.UI.Xaml.Window.Current.Content = this;
lblMsg.Text = "FileUpdateStatus: " + _fileUpdateRequest.Status.ToString();
});
}
async void CachedFileUpdaterUI_UIRequested(CachedFileUpdaterUI sender, object args)
{
// The event handler may be invoked on a background thread, so use the Dispatcher to run the UI-related code on the UI thread.
await dispatcher.RunAsync(CoreDispatcherPriority.Normal, () =>
{
Window.Current.Content = this;
this.OnNavigatedTo(null);
});
}
protected override void OnNavigatedTo(NavigationEventArgs e)
{
// 获取 CachedFileUpdaterUI 对象
var args = (CachedFileUpdaterActivatedEventArgs)e.Parameter;
_cachedFileUpdaterUI = args.CachedFileUpdaterUI;
_cachedFileUpdaterUI.Title = "缓存文件更新程序";
_cachedFileUpdaterUI.FileUpdateRequested += _cachedFileUpdaterUI_FileUpdateRequested;
_cachedFileUpdaterUI.UIRequested += _cachedFileUpdaterUI_UIRequested;
base.OnNavigatedTo(e);
}
async void _cachedFileUpdaterUI_FileUpdateRequested(CachedFileUpdaterUI sender, FileUpdateRequestedEventArgs args)
{
_fileUpdateRequest = args.Request;
FileUpdateRequestDeferral fileUpdateRequestDeferral = _fileUpdateRequest.GetDeferral();
if (_cachedFileUpdaterUI.UpdateTarget == CachedFileTarget.Local) // 由 CachedFileUpdater 更新 CachedFile（CachedFileTarget.Local 方式）
{
// 开始激活 CachedFileUpdater 时，是 UIStatus.Hidden 状态的
if (_cachedFileUpdaterUI.UIStatus == UIStatus.Hidden)
{
// 下面针对两种方式分别写示例
// 方式一：直接更新文件，并设置为 FileUpdateStatus.Complete 状态，最后完成
if (DateTime.Now.Second % 2 == 0)
{
await FileIO.AppendTextAsync(_fileUpdateRequest.File, Environment.NewLine + "由 CachedFileUpdater 更新：" + DateTime.Now.ToString());
_fileUpdateRequest.Status = FileUpdateStatus.Complete;
fileUpdateRequestDeferral.Complete();
}
// 方式二：设置为 FileUpdateStatus.UserInputNeeded 状态，并完成，之后会再次触发这个事件，并且变为 UIStatus.Visible 状态，弹出本页界面，
// 这样的话可以在用户做一些操作之后再更新文件（参见下面的 btnUpdate_Click 部分）
else
{
_fileUpdateRequest.Status = FileUpdateStatus.UserInputNeeded;
fileUpdateRequestDeferral.Complete();
}
}
}
else if (_cachedFileUpdaterUI.UpdateTarget == CachedFileTarget.Remote) // 由 app 更新 CachedFile（CachedFileTarget.Remote 方式）
{
// 这里可以拿到 app 更新后的文件的结果
string textContent = await FileIO.ReadTextAsync(_fileUpdateRequest.File);
// 但是这里不能修改这个文件，否则会报错
// await FileIO.AppendTextAsync(_fileUpdateRequest.File, Environment.NewLine + "由 CachedFileUpdater 更新：" + DateTime.Now.ToString());
// CachedFileUpdater 返回给 app 一个 FileUpdateStatus 状态
_fileUpdateRequest.Status = FileUpdateStatus.Complete;
fileUpdateRequestDeferral.Complete();
}
}
void CachedFileUpdaterUI_FileUpdateRequested(CachedFileUpdaterUI sender, FileUpdateRequestedEventArgs args)
{
fileUpdateRequest = args.Request;
fileUpdateRequestDeferral = fileUpdateRequest.GetDeferral();
switch (cachedFileUpdaterUI.UIStatus)
{
case UIStatus.Hidden:
fileUpdateRequest.Status = FileUpdateStatus.UserInputNeeded;
fileUpdateRequestDeferral.Complete();
break;
case UIStatus.Visible:
break;
case UIStatus.Unavailable:
fileUpdateRequest.Status = FileUpdateStatus.Failed;
fileUpdateRequestDeferral.Complete();
break;
}
}
private void OnFileUpdateRequested(CachedFileUpdaterUI sender, FileUpdateRequestedEventArgs args)
{
switch (sender.UIStatus)
{
case UIStatus.Hidden:
fileUpdateRequest = args.Request;
fileUpdateRequestDeferral = fileUpdateRequest.GetDeferral();
// process cached file
fileUpdateRequestDeferral.Complete();
break;
case UIStatus.Visible:
// use the class fields
fileUpdateRequestDeferral.Complete();
break;
case UIStatus.Unavailable:
fileUpdateRequest.Status = FileUpdateStatus.Failed;
fileUpdateRequestDeferral.Complete();
break;
}
}
