Check out example codes for "check which activity in focus in android". It will help you in understanding the concepts better.
Code Example 1
public class MyApplication extends Application {
public static boolean isActivityVisible() {
return activityVisible;
}
public static void activityResumed() {
activityVisible = true;
}
public static void activityPaused() {
activityVisible = false;
}
private static boolean activityVisible;
}
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