Does Android Have a Built-in Double-Click to Exit Feature?

Android's Back Button: Double Click to Exit Activity

In numerous Android applications, a "double-click to exit" feature has become prevalent. This mechanism prevents unwanted app closures by displaying a toast message after the first back button press, and only terminating the activity upon a second click.

Is it a Built-In Capability?

Despite extensive code analysis, you may have failed to locate a built-in Android feature that executes this functionality. However, there is a straightforward method to replicate it:

Custom Implementation:

By maintaining a boolean variable within the activity, you can implement this feature yourself:

<code class="java">boolean doubleBackToExitPressedOnce = false;

@Override
public void onBackPressed() {
    if (doubleBackToExitPressedOnce) {
        super.onBackPressed();
        return;
    }

    this.doubleBackToExitPressedOnce = true;
    Toast.makeText(this, "Please click BACK again to exit", Toast.LENGTH_SHORT).show();

    new Handler(Looper.getMainLooper()).postDelayed(new Runnable() {

        @Override
        public void run() {
            doubleBackToExitPressedOnce = false;
        }
    }, 2000);
}</code>

Explanation:

• After the first back button press, doubleBackToExitPressedOnce becomes true.
• A message is displayed to notify the user.
• A handler is set to reset doubleBackToExitPressedOnce to false after a 2 second delay.
• On the second press, the activity exits as usual.

Note:

This implementation does not mimic the app launcher behavior entirely. If the app was launched via an intent, it will be replaced by the previous intent instead of the home screen.

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