How to overlay views in other apps

Question

Where do I start?

I don't know what functions or permissions will I use to make this. No root required.

The view look like this, the camera button on the right side, it is floating and visible to other apps, if you push it, it will capture a screenshot.

Note: I will not make make a screenshot app, this is only an example of what I want to achieve.

Answer 1

this called

Draw Over Other Apps

check these answers

"DRAW OVER OTHER APP" is which permission in android

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Answer 2

Try this:

    if(!isSystemAlertPermissionGranted(MainActivity.this)){         requestSystemAlertPermission(MainActivity.this,1);     }      startService(new Intent(getApplicationContext(), Overlay.class)); 

And:

public static void requestSystemAlertPermission(Activity context, int requestCode) {     if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M)         return;     final String packageName = context == null ? context.getPackageName() : context.getPackageName();     final Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION, Uri.parse("package:" + packageName));     if (context != null)         context.startActivityForResult(intent, requestCode);     else         context.startActivityForResult(intent, requestCode); } @TargetApi(23) public static boolean isSystemAlertPermissionGranted(Context context) {     final boolean result = Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP || Settings.canDrawOverlays(context);     return result; }