AlertDialog:为什么我不能一起显示消息和列表？

Question

AlertDialog当我添加消息时,有人知道为什么不显示项目列表.setMessage()吗？将显示负面和正面按钮,但不会显示列表.当我删除所有行的行.setMessage().

这是我的代码:

AlertDialog.Builder myAlertDialog = new AlertDialog.Builder(this.getActivity());
myAlertDialog.setTitle("Options");
myAlertDialog.setMessage("Choose a color.");

CharSequence[] items = {"RED", "BLUE", "GREEN" };

myAlertDialog.setSingleChoiceItems(items, -1, new DialogInterface.OnClickListener() {

    @Override
    public void onClick(DialogInterface dialog, int which) {
        // do stuff
    }
});

myAlertDialog.setNegativeButton("NO",new DialogInterface.OnClickListener() {

    @Override
    public void onClick(DialogInterface dialog, int which) {
       // do stuff
    }
});

myAlertDialog.setPositiveButton("YES",new DialogInterface.OnClickListener() {

    @Override
    public void onClick(DialogInterface dialog, int which) {
       // do stuff
    }
});

myAlertDialog.create();
myAlertDialog.show();

Answer 1

从文档中,

由于列表显示在对话框的内容区域中,因此对话框不能同时显示消息和列表,您应该使用setTitle()为对话框设置标题.

在setMessage()和setSingleChoiceItems()因此是互斥的.

Answer 2

AlertDialog通过检查mMessage您是否通过setMessage()is设置来动态创建其内容null。如果mMessage是NOT null（这意味着你叫setMessage()方法），然后设置其内容只 TextView显示消息和跳过 listview设置。如果您还没有调用setMessage()，那么它会删除TextView然后设置listview。

解决方案

因此，要在对话框中显示消息和列表，我建议您使用以下解决方案，为 AlertDialog 设置自定义视图。

        final AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
    builder.setTitle("Dialog title");

    final List<String> items = new ArrayList<>();

    items.add("Item 1");
    items.add("Item 2");
    items.add("Item 3");

    final ArrayAdapter<String> arrayAdapterItems = new ArrayAdapter<String>(
            getContext(), android.R.layout.simple_list_item_single_choice, items);

    View content = getLayoutInflater().inflate(R.layout.list_msg_dialog, null);

    //this is the TextView that displays your message
    TextView tvMessage = content.findViewById(R.id.tv_msg);

    tvMessage.setText("Dialog message!!!");

    //this is the ListView that lists your items
    final ListView lvItems = content.findViewById(R.id.lv_items);
    lvItems.setAdapter(arrayAdapterItems);
    lvItems.setChoiceMode(ListView.CHOICE_MODE_SINGLE);
    builder.setView(content);
    builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            //do something
            Toast.makeText(MainActivity.this,
                    items.get(lvItems.getCheckedItemPosition()),
                    Toast.LENGTH_SHORT).show();
        }
    });
    final AlertDialog dialog = builder.create();

    lvItems.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            //when you need to act on itemClick
        }
    });


    dialog.show();

这是list_msg_dialog.xml布局：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="3dp">

<TextView
    android:id="@+id/tv_msg"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:paddingLeft="10dp"
    android:paddingTop="15dp"
    android:text="some text"
    android:textAppearance="?android:attr/textAppearanceListItem"
    android:textColor="@android:color/black"
    android:textSize="18sp" />

<ListView
    android:id="@+id/lv_items"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:divider="@null" /></LinearLayout>

Answer 3

尝试在警报对话框中设置项目如下：

  AlertDialog.Builder myAlertDialog = new AlertDialog.Builder(this.getActivity());
  myAlertDialog.setTitle("Options");
  myAlertDialog.setMessage("Choose a color.");
  myAlertDialog.getListView().setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
 CharSequence[] items = {"RED","BLUE","GREEN"};

 myAlertDialog.setItems(items, new DialogInterface.OnClickListener() {

 public void onClick(DialogInterface d, int choice) {

   }
  });
     ............
   myAlertDialog.create();
 myAlertDialog.show();