android - ListView 项目 : change background color to last item selected (or clicked)

Question

我正在开发一个带有 ListActivity 的 Android 2.3.3 应用程序。

我想做一些事情来向用户展示他/她选择了什么项目。我已经完成了以下操作，但没有(我在 stackoverflow 中搜索，它们是相互矛盾的答案)。

这是layout_item.xml

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

    <TextView
        android:id="@+id/txtName"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/selector"
        android:text="" />

</LinearLayout>

这是res/drawable上的selector.xml文件

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_selected="true"
        android:color="#00FF00" />
    <item android:state_pressed="true"
        android:color="#555555" />
    <item android:color="#000000" />
</selector>

但它不起作用，因为它说我必须在 selector.xml 中放置一个 @drawable。

如何将背景颜色设置为蓝色以显示最后单击的列表项？

更新

与此列表一起使用的数组适配器:

public class GatesAdapter extends ArrayAdapter<Gate>
{
    /**
     * Application context.
     */
    private Context context;
    /**
     * 
     */
    private int itemLayoutId;
    /**
     * 
     */
    private ArrayList<Gate> gates;
    private int selectedGateIndex;

    public int getSelectedGateIndex() {
        return selectedGateIndex;
    }

    public void setSelectedGateIndex(int selectedGateIndex) {
        this.selectedGateIndex = selectedGateIndex;
    }

    public Gate getSelectedGate()
    {
        return gates.get(selectedGateIndex);
    }

    public void removeSelectedGate()
    {
        this.gates.remove(selectedGateIndex);
    }

    public ArrayList<Gate> getGates()
    {
        return this.gates;
    }

    public GatesAdapter(Context context, int listItemResourceId,
            ArrayList<Gate> objects)
    {
        super(context, listItemResourceId, objects);

        this.context = context;
        this.itemLayoutId = listItemResourceId;
        this.gates = objects;
        this.selectedGateIndex = -1;

        this.setNotifyOnChange(true);
    }

    @Override
    public int getCount()
    {
        return gates.size();
    }

    @Override
    public View getView(final int position, View convertView, ViewGroup parent)
    {
        Log.v("GatesAdapter", "getView.postion: " + position);
        View row = convertView;
        if (row == null)
        {
            LayoutInflater inflater = ((Activity)context).getLayoutInflater();
            row = inflater.inflate(itemLayoutId, parent, false);
        }

        Gate gate = gates.get(position);
        if (gate != null)
        {
            TextView itemText = (TextView)row.findViewById(android.R.id.text1);
            if (itemText != null)
            {
                itemText.setText(gate.getName());
                //selectedGateIndex = position;
                if (selectedGateIndex == position)
                {
                    row.setBackgroundColor(Color.BLUE);
                }
            }
        }

        return row;
    }
}

Answer 1

我已经用自定义数组适配器完成了，只是在 getView() 方法中检查过:

if (position == lastClicked) {
    v.setBackgroundColor(0x...)
} else {
    v.setBackgroundColor(0x...)
}

由于大型 ListView 的特定行为，else block 很重要

更新:这是我的自定义数组适配器，工作正常:

public class AbcArrayAdapter extends ArrayAdapter<UniversalListItem> {

private Context c;
private int id;
private List<UniversalListItem>items;

public AbcArrayAdapter(Context context, int viewResourceId, List<UniversalListItem> objects){
    super(context,viewResourceId,objects);
    c=context;
    id=viewResourceId;
    items=objects;
}

@Override
public View getView(final int position, View convertView, ViewGroup parent) {
    View v = convertView;
    if (v == null) {
        LayoutInflater vi = (LayoutInflater)c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        v = vi.inflate(id, null);
    }

    final UniversalListItem o = items.get(position);
    if (o != null) {
        if ( o.isInList() ) {
            v.setBackgroundColor(0x00ffffff);
        } else {
            v.setBackgroundColor(0x4d0099cc);
        }
        /*....*/
    }
    return v;
}