Tuve el mismo problema y lo resolví. Para simplificar la vida, escribí una clase util para manejar los permisos de tiempo de ejecución.
public class PermissionUtil {
/*
* Check if version is marshmallow and above.
* Used in deciding to ask runtime permission
* */
public static boolean shouldAskPermission() {
return (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M);
}
private static boolean shouldAskPermission(Context context, String permission){
if (shouldAskPermission()) {
int permissionResult = ActivityCompat.checkSelfPermission(context, permission);
if (permissionResult != PackageManager.PERMISSION_GRANTED) {
return true;
}
}
return false;
}
public static void checkPermission(Context context, String permission, PermissionAskListener listener){
/*
* If permission is not granted
* */
if (shouldAskPermission(context, permission)){
/*
* If permission denied previously
* */
if (((Activity) context).shouldShowRequestPermissionRationale(permission)) {
listener.onPermissionPreviouslyDenied();
} else {
/*
* Permission denied or first time requested
* */
if (PreferencesUtil.isFirstTimeAskingPermission(context, permission)) {
PreferencesUtil.firstTimeAskingPermission(context, permission, false);
listener.onPermissionAsk();
} else {
/*
* Handle the feature without permission or ask user to manually allow permission
* */
listener.onPermissionDisabled();
}
}
} else {
listener.onPermissionGranted();
}
}
/*
* Callback on various cases on checking permission
*
* 1. Below M, runtime permission not needed. In that case onPermissionGranted() would be called.
* If permission is already granted, onPermissionGranted() would be called.
*
* 2. Above M, if the permission is being asked first time onPermissionAsk() would be called.
*
* 3. Above M, if the permission is previously asked but not granted, onPermissionPreviouslyDenied()
* would be called.
*
* 4. Above M, if the permission is disabled by device policy or the user checked "Never ask again"
* check box on previous request permission, onPermissionDisabled() would be called.
* */
public interface PermissionAskListener {
/*
* Callback to ask permission
* */
void onPermissionAsk();
/*
* Callback on permission denied
* */
void onPermissionPreviouslyDenied();
/*
* Callback on permission "Never show again" checked and denied
* */
void onPermissionDisabled();
/*
* Callback on permission granted
* */
void onPermissionGranted();
}
}
Y los métodos PreferenceUtil son los siguientes.
public static void firstTimeAskingPermission(Context context, String permission, boolean isFirstTime){
SharedPreferences sharedPreference = context.getSharedPreferences(PREFS_FILE_NAME, MODE_PRIVATE;
sharedPreference.edit().putBoolean(permission, isFirstTime).apply();
}
public static boolean isFirstTimeAskingPermission(Context context, String permission){
return context.getSharedPreferences(PREFS_FILE_NAME, MODE_PRIVATE).getBoolean(permission, true);
}
Ahora, todo lo que necesita es usar el método checkPermission con los argumentos adecuados.
Aquí hay un ejemplo,
PermissionUtil.checkPermission(context, Manifest.permission.WRITE_EXTERNAL_STORAGE,
new PermissionUtil.PermissionAskListener() {
@Override
public void onPermissionAsk() {
ActivityCompat.requestPermissions(
thisActivity,
new String[]{Manifest.permission.READ_CONTACTS},
REQUEST_EXTERNAL_STORAGE
);
}
@Override
public void onPermissionPreviouslyDenied() {
//show a dialog explaining permission and then request permission
}
@Override
public void onPermissionDisabled() {
Toast.makeText(context, "Permission Disabled.", Toast.LENGTH_SHORT).show();
}
@Override
public void onPermissionGranted() {
readContacts();
}
});
Caso 1: La aplicación no tiene permiso y no se le ha pedido permiso al usuario antes. En este caso, shouldShowRequestPermissionRationale () devolverá false porque es la primera vez que le preguntamos al usuario.
Caso 2: el usuario ha denegado el permiso y ha seleccionado "No volver a preguntar", en este caso también shouldShowRequestPermissionRationale () devolverá false.
Me gustaría enviar al usuario a la página de configuración de la aplicación en el Caso 2. ¿Cómo hago para diferenciar estos dos casos?
Recibirá devolución de llamada en onPermissionAsk para el caso 1 y onPermissionDisabled para el caso 2.
Feliz codificación :)