Question

我有以下代码可以删除点击的项目：

listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
                        int position, long id) {
    String itemValue = (String) listView.getItemAtPosition(position);
    email_addresses.remove(position);

    String size = Integer.toString(email_addresses.size());
    Log.d("Size: ", size);

    //listView = (ListView) findViewById(R.id.email_list);
    //ArrayAdapter<String> adapter = new ArrayAdapter<>(getApplicationContext(), android.R.layout.simple_list_item_1, android.R.id.text1, email_addresses);
    //listView.setAdapter(adapter);
    ArrayAdapter<String> adapter = new ArrayAdapter<>(mainAppContext, android.R.layout.simple_list_item_1, android.R.id.text1, email_addresses);
    ((ListView)parent).setAdapter(adapter);
    parent.refreshDrawableState();
}

当我点击某个项目时，列表会被清除，并且不会显示任何内容。大小是正确的值，列表可以重建，但我无法使此代码工作。谢谢

Answer 1

您是不是每次都创建一个全新的适配器，而是考虑简单地将您的适配器变为成员变量并调用notifyDataSetChanged？

ArrayAdapter<String> adapter = new ArrayAdapter<>(mainAppContext, android.R.layout.simple_list_item_1, android.R.id.text1, email_addresses);
((ListView)parent).setAdapter(adapter);

变为：

mAdapter.notifyDataSetChanged();

Answer 2

将列表和适配器定义为即时变量，并且还必须通知适配器以使删除受影响，试试这个，

        listview.setOnItemClickListener(new OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent, View view,
                int position, long id) {
            email_addresses.remove(position);
            adapter .notifyDataSetChanged();
        }
    });

ListView onClick update清除列表

2 个答案: