Question

如何在按钮单击时将图像的第一个位置移动到ListView中的第二个位置，以便图像的最后位置到达第一个位置。

我在下面尝试过的代码;

public class MainActivity extends AppCompatActivity {

private int[] images = {R.drawable.img1,R.drawable.img2,R.drawable.img3,R.drawable.img4,R.drawable.img5};
ArrayList<ImageModel> imageModels;

@Override
protected void onCreate (Bundle savedInstanceState) {
    super.onCreate (savedInstanceState);
    setContentView (R.layout.activity_main);

    imageModels = new ArrayList<ImageModel> ();
    for (int i = 0; i < images.length; i++) {
        ImageModel imgMode = new ImageModel ();
        imgMode.setImageId (images[i]);
        imageModels.add (imgMode);
        Log.d ("chk",""+images[i]);
    }

    ListView lstView = (ListView)findViewById (R.id.lst_view);
    lstView.setAdapter (new BaseAdapterr(MainActivity.this,imageModels));

    Button btnClick = (Button)findViewById (R.id.btn_click);
    btnClick.setOnClickListener (new View.OnClickListener () {
        @Override
        public void onClick (View v) {
           for (int i=0 ;i < imageModels.size ();i++){
           }
        }
    });
}}

Answer 1

尝试使用获取对象索引，然后使用setIndex或sth来更改索引。

拉茶

Answer 2

直接滚动：

  lstView.setSelection(0);

顺畅滚动：

  lstView.smoothScrollToPosition(0);

因此您的代码应该遵循

btnClick.setOnClickListener (new View.OnClickListener () {
    @Override
    public void onClick (View v) {
           lstView.clearFocus();
           lstView.post(new Runnable() {
           @Override
           public void run() {
              //int index=0; set your position
           lstView.setSelection(index);
           }
          });
    }
});

Answer 3

这是你的 btnClick听众，试一试：

      Button btnClick = (Button)findViewById (R.id.btn_click);
        btnClick.setOnClickListener (new View.OnClickListener () {
            @Override
            public void onClick (View v) {
               ...

              ImageView firstImage= listView.getChiledAt(0);// get the firstimage 
              ImageView secnodImage= listView.getChiledAt(1);// get the second image
              listView.addView(firstImage,2);// we added the first image to the second index
              listView.addView(secondImage,1);// we added the second image to the first index
              myAdapter.notifyDataSetChanged();// to refresh the view

               ...
            }
        });

如何将图像的第一个位置移动到listView上的第二个位置按钮点击android

3 个答案: