Question: I've been getting reports of some Xiaomi devices (e.g. Mi 2, running API level 21) not showing overlays. My app targets API 23.

There are [several](http://forum.xda-developers.com/xiaomi-mi-3/help/link-bubble-playing-nice-t2857607) [posts](http://en.miui.com/thread-30931-1-1.html) out there regarding this. It seems that MIUI devices do not enable this permission at install time (unlike other pre-Marshmallow devices).

Unfortunately, `Settings.canDrawOverlays()` only works on Android 23+.

1. What is the correct way to check whether this permission has not yet been enabled pre-Marshmallow?
2. Is there an Intent to take the user to the relevant MUIU settings page? Maybe: `new Intent("android.settings.action.MANAGE_OVERLAY_PERMISSION", packageName)` but I have no means to test this.

Answer: 
1) on pre-API 23, the permission is already given, because the user granted it upon install.

EDIT: it seems there is a bug on Android 6 (that will [**get fixed on 6.0.1**](https://code.google.com/p/android/issues/detail?id=196597)), that if the user has denied this permission , the app will crash with SecurityException. No idea how Google fixed it though.

2) This way:

```
public static void requestSystemAlertPermission(Activity context, Fragment fragment, int requestCode) {
    if (VERSION.SDK_INT < VERSION_CODES.M)
        return;
    final String packageName = context == null ? fragment.getActivity().getPackageName() : context.getPackageName();
    final Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION, Uri.parse("package:" + packageName));
    if (fragment != null)
        fragment.startActivityForResult(intent, requestCode);
    else
        context.startActivityForResult(intent, requestCode);
}

```

Then, in the onActivityResult, you can check if the permission is given or not, as such:

```
@TargetApi(VERSION_CODES.M)
public static boolean isSystemAlertPermissionGranted(Context context) {
    final boolean result = VERSION.SDK_INT < VERSION_CODES.M || Settings.canDrawOverlays(context);
    return result;
}

```

---

EDIT: for the time being, if you publish an app to the Play Store, your app will be auto-granted with this permission. You can read about it [**here**](https://commonsware.com/blog/2016/03/24/system-alert-window-now-more-hidden-than-ever.html). When I asked about it, I thought it was a part of Android itself, as I thought all we need is to target a high enough value for targetSdkVersion. What Google wrote to me ([**here**](https://code.google.com/p/android/issues/detail?id=222195)) is that they wanted to avoid issues on popular apps. 

I suggest handling this permission correctly even if you will get it auto-granted.
Here is the step by step how to handle this:

At first give below permission in manifest file:

```
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />

```

Or 

```
<uses-permission-sdk-23 android:name="android.permission.SYSTEM_ALERT_WINDOW" />

```

Then handle rest of the things using below code:

```
 public final static int REQUEST_CODE = 65635;

    public void checkDrawOverlayPermission() {
        /** check if we already  have permission to draw over other apps */
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (!Settings.canDrawOverlays(this)) {
                /** if not construct intent to request permission */
                Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION,
                        Uri.parse("package:" + getPackageName()));
                /** request permission via start activity for result */
                startActivityForResult(intent, REQUEST_CODE);
            }
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode,  Intent data) {
        /** check if received result code
         is equal our requested code for draw permission  */
        if (requestCode == REQUEST_CODE) {
            // ** if so check once again if we have permission */
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                if (Settings.canDrawOverlays(this)) {
                    // continue here - permission was granted
                    goYourActivity();
                }
            }
        }
    }

```

Just call `checkDrawOverlayPermission()` from your LauncherActivity or anywhere as your requirements.

When you execute the project you will see a window and asked for enabling the permission. After allowing permission you will be able to do anything about this.