如何使用适配器在按钮单击上添加ListView项目

Question

如何获取在EditText中输入的数据并在该窗口中单击"提交"应该将其添加到以前的活动列表视图项？我需要做的是:

1. 创建EditText并提交按钮
2. 在同一个Activity中创建listview
3. 通过单击提交按钮,它应该在列表视图中显示.

我在这里看到了类似的问题:向listview动态添加项目android

但我无法理解答案.有人请解释如何做到这一点.

Answer 1

您只需执行以下操作:准备您的xml,如下所示:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:tools="http://schemas.android.com/tools"
 android:layout_width="match_parent"
 android:layout_height="match_parent" >

  <EditText
     android:id="@+id/editText"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:layout_alignParentTop="true"
     android:layout_toLeftOf="@+id/addItem"
     android:hint="Add a new item to List View" />

  <Button
     android:id="@+id/addItem"
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:layout_alignParentRight="true"
     android:text="Add" /> 

  <ListView
     android:id="@+id/listView"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:layout_below="@+id/editText" >
  </ListView>

</RelativeLayout>

活动如下:

public class MainActivity extends Activity {
    EditText editText;
    Button addButton;
    ListView listView;
    ArrayList<String> listItems;
    ArrayAdapter<String> adapter;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        editText = (EditText) findViewById(R.id.editText);
        addButton = (Button) findViewById(R.id.addItem);
        listView = (ListView) findViewById(R.id.listView);
        listItems = new ArrayList<String>();
        listItems.add("First Item - added on Activity Create");
        adapter = new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_1, listItems);
        listView.setAdapter(adapter);
        addButton.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
                listItems.add(editText.getText().toString());
                adapter.notifyDataSetChanged();
            }
        });
        listView.setOnItemClickListener(new OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> a, View v, int position,
                    long id) {
                Toast.makeText(MainActivity.this, "Clicked", Toast.LENGTH_LONG)
                        .show();
            }
        });
    }
}