android - 如何更改 Android M 中的拒绝/授予权限？

Question

我怎样才能让用户有机会更改他在应用程序中的权限，他已经设置为授予/拒绝？

假设用户拒绝了权限。后来他想授予此权限。是否可以？我该怎么做？

Answer 1

如果用户拒绝了权限，您可以检查权限，如果他也检查了不再显示，在这种情况下，您可以打开自己的对话框，解释您的应用程序需要该权限，然后从该对话框中您可以将用户带到应用程序设置，如果他愿意，他可以在其中允许权限。

public static void checkPermissionForExternalStorage(final Context mContext) {

    if (Build.VERSION.SDK_INT >= 23) {

        int writeExternalStorage = ContextCompat.checkSelfPermission(mContext, Manifest.permission.WRITE_EXTERNAL_STORAGE);
        if (writeExternalStorage != PackageManager.PERMISSION_GRANTED) {

            ActivityCompat.requestPermissions((Activity) mContext, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, REQUEST_CODE_ASK_PERMISSIONS_FOR_STORAGE);
            return;
        }

        //Do your stuff

    } else {

       //Do your stuff
    }
}



 public static void startInstalledAppDetailsActivity(Context mContext) {

    Intent i = new Intent();
    i.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
    i.addCategory(Intent.CATEGORY_DEFAULT);
    i.setData(Uri.parse("package:" + mContext.getPackageName()));
    i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    i.addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
    i.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
    mContext.startActivity(i);
}



   @Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {

    switch (requestCode) {



        case REQUEST_CODE_ASK_PERMISSIONS_FOR_STORAGE:
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                //Do your stuff
            } else {
                // Permission Denied

                if (!ActivityCompat.shouldShowRequestPermissionRationale((Activity) mContext, Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
                    showMessageOKCancel("The app was not allowed to write to your storage. Hence, it cannot function properly. Please consider granting it this permission. Tap Settings > Permissions, and turn Storage on.",
                            new DialogInterface.OnClickListener() {
                                @Override
                                public void onClick(DialogInterface dialog, int which) {
                                    startInstalledAppDetailsActivity((Activity) mContext);
                                }
                            });
                }


                Toast.makeText( mContext, "Write to external storage permission request denied.", Toast.LENGTH_SHORT).show();
            }
            break;
        default:
            super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    }
}