Android "Only the original thread that created a view hierarchy can touch its views."

Android "Only the original thread that created a view hierarchy can touch its views." - Easy solutions 👀📱

Are you trying to update a TextView in your Android app, but getting an annoying exception that says "Only the original thread that created a view hierarchy can touch its views"? 🤔 Well, don't worry! We've got you covered with easy solutions to this common issue. Let's dive in! 💪

The Problem 😩

First, let's understand the problem. The Android UI toolkit is not thread-safe, which means that all UI-related updates should be done on the main UI thread (also known as the "UI thread" or "main thread"). When you try to update a view from a different thread, you'll encounter the dreaded "CalledFromWrongThreadException" exception. This exception is thrown to prevent potential synchronization issues and ensure UI consistency. 🚫🔄

The Solution ✅

There are a few different ways you can solve this problem and update your views from the UI thread. Let's explore the two main approaches:

1. Using runOnUiThread 🏃‍♀️

One simple way to update a view from a different thread is to use the runOnUiThread method provided by the Activity class. Here's how you can do it:

runOnUiThread(new Runnable() {
    public void run() {
        // Update your view here
        currentTime.setText(time);
    }
});

In this approach, you create a new Runnable that contains the code to update your view, and then pass it to the runOnUiThread method. This method ensures that the run method of your Runnable is executed on the UI thread.

2. Using Handler 🎈

Another approach is to use a Handler to post a Runnable to the UI thread's message queue. Here's an example:

Handler handler = new Handler(Looper.getMainLooper());
handler.post(new Runnable() {
    public void run() {
        // Update your view here
        currentTime.setText(time);
    }
});

In this approach, you create a new Handler that is associated with the UI thread's message queue. Then, you use the post method to add your Runnable to the message queue. The run method of your Runnable will be executed on the UI thread.

Putting It All Together 🔄🎛

Now that you know the solutions, let's go back to your specific issue. To update the TextView from the run method, you can use either of the following approaches:

runOnUiThread(new Runnable() {
    public void run() {
        String time = String.format("%d:%d",
            TimeUnit.MILLISECONDS.toMinutes(pos),
            TimeUnit.MILLISECONDS.toSeconds(pos),
            TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(
                    pos))
        );
        currentTime.setText(time);  
    }
});

or

Handler handler = new Handler(Looper.getMainLooper());
handler.post(new Runnable() {
    public void run() {
        String time = String.format("%d:%d",
            TimeUnit.MILLISECONDS.toMinutes(pos),
            TimeUnit.MILLISECONDS.toSeconds(pos),
            TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(
                    pos))
        );
        currentTime.setText(time);  
    }
});

Both approaches will ensure that the setText method is executed on the main UI thread, avoiding the "CalledFromWrongThreadException" exception. 🎉

Conclusion 🎉📝

Updating views from a different thread in Android can be a bit tricky, but with the right solutions, you can easily overcome this issue. Remember to either use runOnUiThread or Handler to ensure that your UI updates are performed on the main UI thread.

We hope this guide helped you solve the "Only the original thread that created a view hierarchy can touch its views" problem! If you have any other questions or face other tech challenges, let us know in the comments below. We're always here to help! 😊👍

Now, go ahead and update those views like a pro! 🚀💻