Android:自定义列表视图中的单选按钮

Question

我正在开发一个应用程序,我需要在列表视图中实现单选按钮.我想实现一个列表视图,每行有一个单选按钮和两个文本视图.列表视图下方有一个"确定"按钮.

我所做的是创建了一个列表视图和一个自定义适配器.listview的代码如下:

<ListView
    android:id="@+id/listview"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:cacheColorHint="#00000000"
    android:overScrollMode="never"
    tools:ignore="NestedScrolling"
    android:choiceMode="singleChoice" >
</ListView>

我创建了一个自定义适配器布局:

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

    <TableRow
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        tools:ignore="UselessParent" >

        <RadioButton
            android:id="@+id/radiobutton"
            android:layout_width="0sp"
            android:layout_height="wrap_content"
            android:layout_weight=".1" />

        <TextView
            android:id="@+id/textview1"
            android:layout_width="0sp"
            android:layout_height="wrap_content"
            android:layout_weight=".3" />

        <TextView
            android:id="@+id/textview2"
            android:layout_width="0sp"
            android:layout_height="wrap_content"
            android:layout_weight=".3" />

    </TableRow>

</TableLayout>

片段的java代码如下:

ListView listView = (ListView) view.findViewById(R.id.listview);

// values is a StringArray holding some string values.
CustomAdapter customAdapter = new CustomAdapter (getActivity(), values);
listView.setAdapter(customAdapter );
listView.setOnItemClickListener(this);

@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int position, long arg3) {}

适配器的代码如下:

public class CustomAdapter extends ArrayAdapter<String> {   
    /** Global declaration of variables. As there scope lies in whole class. */
    private Context context;
    private String[] listOfValues;

    /** Constructor Class */
    public CustomAdapter (Context c,String[] values) {
        super(c,R.layout.adapter_layout,values);
        this.context = c;
        this.listOfValues = values;
    }

    /** Implement getView method for customizing row of list view. */
    public View getView(final int position, View convertView, ViewGroup parent) {
        LayoutInflater inflater = ((Activity)context).getLayoutInflater();
        // Creating a view of row.
        View rowView = inflater.inflate(R.layout.adapter_layout, parent, false);

            TextView textView1 = (TextView)rowView.findViewById(R.id.textview1);
            TextView textView2 = (TextView)rowView.findViewById(R.id.textview2);

            RadioButton radioButton = (RadioButton) rowView.findViewById(R.id.radiobutton);

            radioButton.setOnClickListener(new OnClickListener() {          
            @Override   
            public void onClick(View v) {
                Toast.makeText(context, CustomAdapter[position], Toast.LENGTH_SHORT).show();
            }
        });

        return rowView;
    }
}    

textview1的数据填充在SQLite数据库中,而textview2上的数据是"状态关闭".在选择或单击任何单选按钮时,文本视图的文本将更改为"状态打开".

问题是:应用程序的需要是只有一个单选按钮应该被选中,textview2的数据会在选择时发生变化.当用户点击另一个单选按钮时,它将被选中,前一个应该取消选择,textview2的文本将更改为先前选择的单选按钮的"状态已关闭",并单击单选按钮以"状态打开".

编辑1:

并点击"确定"按钮我想得到列表视图textview1和textview2的位置,文本,因为我想在deview中的SQLite数据库中保存该文本.

请指导我应该遵循哪些步骤.我正处于申请中间.您需要提供宝贵的指导.

Answer 1

以下是关键想法

• RadioButton检查a时,我们必须调用notifyDataSetChanged(),以便更新所有视图.
• 当一个RadioButton被选中,我们必须设置selectedPosition,以跟踪哪些RadioButton选择
• Views在里面回收ListView.因此,他们的绝对位置发生了变化ListView.因此,在里面ListAdapter#getView(),我们必须呼吁setTag()每一个RadioButton.这允许我们RadioButton在RadioButton单击时确定列表中的当前位置.
• RadioButton#setChecked()必须在内部更新getView()新的或预先存在的Views.

下面是我编写和测试的ArrayAdapter示例,以演示这些想法

public class MainActivity extends ListActivity {

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

        // I do no use these values anywhere inside the ArrayAdapter. I could, but don't.
        final Integer[] values = new Integer[] {1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,};

        ArrayAdapter<Integer> adapter = new ArrayAdapter<Integer>(this, R.layout.row, R.id.textview, values) {

            int selectedPosition = 0;

            @Override
            public View getView(int position, View convertView, ViewGroup parent) {
                View v = convertView;
                if (v == null) {
                    LayoutInflater vi = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                    v = vi.inflate(R.layout.row, null);
                    RadioButton r = (RadioButton)v.findViewById(R.id.radiobutton);
                }
                TextView tv = (TextView)v.findViewById(R.id.textview);
                tv.setText("Text view #" + position);
                RadioButton r = (RadioButton)v.findViewById(R.id.radiobutton);
                r.setChecked(position == selectedPosition);
                r.setTag(position);
                r.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View view) {
                        selectedPosition = (Integer)view.getTag();
                        notifyDataSetChanged();
                    }
                });
                return v;
            }

        };
        setListAdapter(adapter);
    }
}