Question

我想在图像视图点击的数组列表中添加一些元素后更新列表视图。任何人都可以帮助我，我该怎么做？

这是我的代码。

public class DealDetailActivity extends Activity {

    private ListView lvAddDocument;
    private ImageView ivAddDocument;

    private ArrayList<String> list;

    // private ArrayAdapter<String> adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.deal_detail_screen);

        list = new ArrayList<String>();

        lvAddDocument = (ListView) findViewById(R.id.lv_add_document);
        ivAddDocument = (ImageView) findViewById(R.id.iv_add_document);

        ivAddDocument.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub

                list.add("rohit");
                Log.i("list", "" + list.size());

                ArrayAdapter<String> adapter = new ArrayAdapter<String>(
                        DealDetailActivity.this,
                        android.R.layout.simple_list_item_1, list);

                lvAddDocument.setAdapter(adapter);
                adapter.notifyDataSetChanged();
            }
        });

    }
}

Answer 1

这样做：

@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.deal_detail_screen);

list = new ArrayList<String>();
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
         DealDetailActivity.this,
         android.R.layout.simple_list_item_1, list);

lvAddDocument = (ListView) findViewById(R.id.lv_add_document);
lvAddDocument.setAdapter(adapter);


ivAddDocument = (ImageView) findViewById(R.id.iv_add_document);

ivAddDocument.setOnClickListener(new OnClickListener() {

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub

        adapter.add("rohit");
        Log.i("list", "" + list.size());
        adapter.notifyDataSetChanged();
    }
});

Answer 2

尝试将Adapter从匿名类中删除：

public class DealDetailActivity extends Activity {

private ListView lvAddDocument;
private ImageView ivAddDocument;

 private ArrayList<String> list;

private ArrayAdapter<String> adapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.deal_detail_screen);

list = new ArrayList<String>();

lvAddDocument = (ListView) findViewById(R.id.lv_add_document);
ivAddDocument = (ImageView) findViewById(R.id.iv_add_document);

adapter = new ArrayAdapter<String>(
                DealDetailActivity.this,
                android.R.layout.simple_list_item_1, list);

lvAddDocument.setAdapter(adapter);

ivAddDocument.setOnClickListener(new OnClickListener() {

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub

        list.add("rohit");
        Log.i("list", "" + list.size());

        adapter.notifyDataSetChanged();
    }
});

}
 }

Answer 3

adapter.notifyDataSetChanged();
lvAddDocument.setAdapter(adapter);

首先尝试通知adapterand然后将该适配器设置为listview.Hope这将起作用。

Answer 4

1）您必须将arrayList声明为全局arraylist意味着：

 ArrayList<DemoClass> arrlistDemo;

然后在onCreate方法中你必须创建你的arrayList Like：

arrlistDemo = new ArrayList<DemoClass>();

2）每当你想要添加项目时，你只需要向arrayList添加项目，而不是调用notifyDatasetChanged（）方法。你的listView将更新其他数据。

添加数据后更新列表视图

4 个答案: