public override bool OnOptionsItemSelected(IMenuItem item)
{
if (item.ItemId == global::Android.Resource.Id.Home)
BackPressed?.Invoke(this, EventArgs.Empty);
return base.OnOptionsItemSelected(item);
}
private void OnBackRequested(object sender, BackRequestedEventArgs e)
{
Frame frame = Window.Current.Content as Frame;
BackPressEventArgs args = new BackPressEventArgs(frame?.CanGoBack, BackPressAction.GoBack);
BackPressed?.Invoke(this, args);
switch (args.Action)
{
case BackPressAction.Handled:
e.Handled = true;
break;
case BackPressAction.Unhandled:
e.Handled = false;
break;
case BackPressAction.GoBack:
if (frame?.CanGoBack == true)
{
e.Handled = true;
frame.GoBack();
}
break;
}
}
public override bool OnOptionsItemSelected(IMenuItem item)
{
if (item.ItemId == 16908332) // Android.Resource.Id.BackButton - which is internal
{
BackPressed?.Invoke(this, EventArgs.Empty);
}
return(base.OnOptionsItemSelected(item));
}
private void _navigationManager_BackRequested(object sender, global::Windows.UI.Core.BackRequestedEventArgs e)
{
var cancelEventArgs = new CancelEventArgs();
BackPressed?.Invoke(sender, cancelEventArgs);
if (cancelEventArgs.Cancel)
{
e.Handled = true;
}
}
public override void OnBackPressed()
{
CancelEventArgs args = new CancelEventArgs();
BackPressed?.Invoke(this, args);
if (!args.Cancel)
{
base.OnBackPressed();
}
}
/// <summary>
/// Handles the back button press and navigates through the history of the root frame.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">Details about the back button press.</param>
void App_BackRequested(object sender, Windows.UI.Core.BackRequestedEventArgs e)
{
if (!(Window.Current.Content is Frame frame))
{
return;
}
BackPressed?.Invoke(sender, e);
if (frame.CanGoBack && !e.Handled)
{
frame.GoBack();
e.Handled = true;
}
}
// To support using the Fragment Backstack with back press
// Override OnBackPress and have it call this utility method
public void OnBackPressWithFragmentManagement()
{
BackPressed?.Invoke(this, EventArgs.Empty);
if (SupportFragmentManager.BackStackEntryCount > 1)
{
// get the fragment to be popped
SupportFragmentManager.PopBackStackImmediate();
var entry = SupportFragmentManager.GetBackStackEntryAt(SupportFragmentManager.BackStackEntryCount - 1);
var frag = SupportFragmentManager.FindFragmentByTag(entry.Name);
FragmentPoppedOnBack?.Invoke(null, frag);
}
else
{
if (SupportFragmentManager.BackStackEntryCount == 1)
{
SupportFragmentManager.PopBackStackImmediate();
}
base.OnBackPressed();
}
}
private async void NativeAppWindow_BackPressed(object sender, System.ComponentModel.CancelEventArgs e)
{
BackPressed?.Invoke(this, e);
if (e.Cancel)
{
return;
}
var currentContent = ViewModel?.GetFinalContent();
if (currentContent != null)
{
// We assume going back succeeded
bool wentBack = true;
var task = ViewModel.HandleUserInteractionAsync("GoBack", delegate
{
// Sometimes this might happen asynchronously if there was another pending UI action,
// but in those cases we would want to cancel the back press anyways. And for the case
// of exiting the app, as long as no other pending UI action was occurring, this would
// happen synchronously, and return false, and not cancel the back press
wentBack = currentContent.GoBack();
});
e.Cancel = wentBack;
try
{
await task;
}
catch (Exception ex)
{
ExceptionHelper.ReportHandledException(ex);
}
}
}
private void OnBackPressed()
{
BackPressed?.Invoke();
}
public void BackButtonPressed()
{
BackPressed?.Invoke();
}
public override void OnBackPressed()
{
BackPressed?.Invoke(this, EventArgs.Empty);
base.OnBackPressed();
}
private void backButton_Click(object sender, EventArgs e)
{
BackPressed.Invoke(this, e);
}
private void RaiseBackPressed()
{
BackPressed?.Invoke(this, new EventArgs());
}
private void Activity_BackPressed(object sender, System.ComponentModel.CancelEventArgs e)
{
BackPressed?.Invoke(this, e);
}
public ScoreScreen()
{
BuildUI();
Back.Click += (sender, e) => BackPressed?.Invoke(sender, e);
}
private void Back_Click(object sender, EventArgs e) => BackPressed?.Invoke(this, null);