Android：应用程序启动时，sharedPreferences URI 为 null

Question

这个想法是将内部存储中的图像保存在共享首选项中并加载到图像视图中。 当应用程序重新启动时，我需要 imageview 来显示保存的图像。 我还授予了 uri 的权限。

我正在尝试类似的事情。

 static int PICK_IMAGE_REQUEST=1;
 static SharedPreferences preferences;

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_profile);
        PROFILE_IMG = (ImageView)findViewById(R.id.profile_image);
        PHOTObutton = (Button)findViewById(R.id.photo_btn);


       // Get from the SharedPreferences
       preferences = PreferenceManager.getDefaultSharedPreferences(this);

        String mImageUri = preferences.getString("image", null);
        PROFILE_IMG.setImageURI(Uri.parse(mImageUri));

        //open gallery-- select profile photo
        PHOTObutton.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                openGallery();
            }
        });

    }
    private void openGallery() {

        Intent intent;
        if (Build.VERSION.SDK_INT < 19) {
            intent = new Intent(Intent.ACTION_GET_CONTENT);
        } else {
            intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
            intent.addCategory(Intent.CATEGORY_OPENABLE);
        }
        intent.setType("image/*");
        startActivityForResult(Intent.createChooser(intent, "Select Picture"),
                PICK_IMAGE_REQUEST);
    }
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data){
        // Check which request we're responding to
        if (requestCode == PICK_IMAGE_REQUEST) {
            // Make sure the request was successful
            if (resultCode == RESULT_OK) {
                // The user picked a image.
                // The Intent's data Uri identifies which item was selected.
                if (data != null) {

                    // This is the key line item, URI specifies the name of the data
                   imageUri = data.getData();

                    // Removes Uri Permission so that when you restart the device, it will be allowed to reload.
                    this.grantUriPermission(this.getPackageName(), imageUri, Intent.FLAG_GRANT_READ_URI_PERMISSION);
                    final int takeFlags = Intent.FLAG_GRANT_READ_URI_PERMISSION;
                    this.getContentResolver().takePersistableUriPermission(imageUri, takeFlags);

                    // Saves image URI as string to Default Shared Preferences
                     preferences =
                            PreferenceManager.getDefaultSharedPreferences(this);
                    SharedPreferences.Editor editor = preferences.edit();
                    editor.putString("image", String.valueOf(imageUri));
                    editor.commit();

                    // Sets the ImageView with the Image URI
                    PROFILE_IMG.setImageURI(imageUri);
                    PROFILE_IMG.invalidate();
                }
            }
        }
    }

当我尝试开始活动时，我得到以下信息。

java.lang.RuntimeException: Unable to start activity ComponentInfo{firebasesearch.activity_profile}: java.lang.NullPointerException: uriString

我该如何解决这个问题？

PS：我试过stackoverflow关于NullPointerException的帖子。 它没有帮助我。 所以请不要提及它。