java - 将图像加载到 imageView 中

Question

我是一名新的 Android 开发人员，我的第一个 Intent 任务是从图库中选择一张图像并将其显示到 ImageView 中，所以我所做的如下:

xml:

 <Button
    android:id="@+id/Intent_btn"
    android:layout_width="200dp"
    android:layout_height="200dp"
    android:layout_alignBaseline="@+id/button1"
    android:layout_alignBottom="@+id/button1"
    android:layout_marginLeft="16dp"
    android:layout_toRightOf="@+id/button1"
    android:text="Intent button"
    android:onClick="openGallery" />

<ImageView
    android:id="@+id/imageView1"
    android:layout_width="100dp"
    android:layout_height="100dp"
    android:layout_alignRight="@+id/Intent_btn"
    android:layout_centerVertical="true" />

代码:

ImageView imageview1;
 protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
     imageview1=(ImageView)findViewById(R.id.imageView1);
}

  public void openGallery(View v)
{
  Intent intent = new  Intent(Intent.ACTION_PICK,android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
 startActivityForResult(intent, RESULT_LOAD_IMAGE); 
}

  @Override
  protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);

if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK
        && null != data) {
    Uri selectedImage = data.getData();
    String[] filePathColumn = {MediaStore.Images.Media.DATA};

    Cursor cursor = getContentResolver().query(selectedImage, filePathColumn, null, null, null);
    cursor.moveToFirst();

    int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
    String filePath = cursor.getString(columnIndex);
    cursor.close();
    Bitmap yourSelectedImage = BitmapFactory.decodeFile(filePath);
    imageview1.setImageBitmap(yourSelectedImage); 
}
}

我设法打开图库并选择一张图像，但它从未加载，这会是什么问题？

Answer 1

向 list 文件添加权限:

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