- 1 year ago
Saving data when suspending UWP app with multiple windows/views: UI Thread not responding
When dealing with suspending and resuming a Universal Windows Platform (UWP) app that uses multiple windows/views, you need to ensure that your app's UI thread is properly managed to prevent it from becoming unresponsive. Here are some general steps to address the issue of the UI thread not responding when saving data during the app's suspension:
Use Background Threads for Heavy Tasks:
During suspension, you should avoid performing heavy tasks on the main UI thread, such as saving large amounts of data. Instead, offload these tasks to background threads or asynchronous operations to keep the UI thread responsive.Implement Suspending and Resuming Handlers:
In yourApp.xaml.cs
file, implement theOnSuspending
andOnResuming
event handlers. TheOnSuspending
handler is where you can save your app's state before suspension, and theOnResuming
handler is where you can restore the app's state after resuming.Use Async-Await Patterns:
Utilize theasync
andawait
keywords to handle asynchronous tasks, ensuring that your app's UI remains responsive. This is especially important for tasks that might take time, such as saving data to a file or a database.Ensure Proper Threading:
Be cautious about accessing UI elements and data from non-UI threads. Use theDispatcher
to marshal UI-related operations back to the UI thread when necessary.Progress and Feedback:
Provide users with feedback about what's happening during suspension and resumption. This could be done through loading indicators or progress bars.Handle Edge Cases:
Account for edge cases where the user might try to interact with the app while it's suspending or resuming. Prevent interactions that could disrupt the process.
Here's a simplified example of how to handle data saving during suspension using async
and await
:
csharpprotected override async void OnSuspending(object sender, SuspendingEventArgs e)
{
var deferral = e.SuspendingOperation.GetDeferral();
// Save app data asynchronously
await SaveDataAsync();
deferral.Complete();
}
In the above code, the SaveDataAsync
method is responsible for saving your app's data to storage. It should be an asynchronous method that properly handles background tasks.
Remember, the specifics of your implementation may vary based on your app's architecture and requirements. However, following these general principles should help you manage the UI thread during suspension and resumption, even in scenarios with multiple windows/views.