ListView, highlight the selected item

Question

I create a ListView in my activity, with another two button (prev, next) to move a highlight on the ListView. When click the two button, I call setSelection(pos), but there's no highlight shown on list view.

I have also tried custom the list item with layout file, and register selectors on it, as described in: http://android-codes-examples.blogspot.com/2011/03/customized-listview-items-selection.html

Unfortunately it is not working as expected. This method did change the color when I touch the list item, but no highlight is shown when I call setSelection().

layout/main.xml (main layout):

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="horizontal"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:weightSum="4"
    >
    <ListView
        android:id="@+id/list_view"
        android:layout_width="match_parent"
        android:layout_height="fill_parent"
        android:layout_weight="1" />
    <LinearLayout
        android:orientation="vertical"
        android:weightSum="2"
        android:layout_width="match_parent"
        android:layout_height="fill_parent"
        android:layout_weight="3">
        <Button
            android:id="@+id/btn_prev"
            android:text="prev"
            android:layout_width="fill_parent"
            android:layout_height="match_parent"
            android:layout_weight="1" />
        <Button
            android:id="@+id/btn_next"
            android:text="next"
            android:layout_width="fill_parent"
            android:layout_height="match_parent"
            android:layout_weight="1" />
    </LinearLayout>
</LinearLayout>

List.java (Activity):

package com.android.list;

import android.app.Activity;
import android.os.Bundle;

import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.TableRow;
import android.widget.SimpleAdapter;
import android.widget.SimpleAdapter.ViewBinder;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.graphics.Point;
import android.graphics.Color;

import java.util.ArrayList;
import java.util.HashMap;

public class List extends Activity
    implements View.OnClickListener
{
    private ArrayList<HashMap<String, String>> mList;
    private Button mPrev;
    private Button mNext;
    private ListView mListView;
    private int mPosition;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        mList = new ArrayList<HashMap<String, String>>();
        HashMap<String, String> map;
        String[] ent = { "USA","India","England","Russia","Europe","Canada","Srilanka","Singapore","Thailand","Australia"};
        for (int i=0; i<ent.length; i++)
        {
            map = new HashMap<String, String>();
            map.put("content", ent[i]);
            mList.add(map);
        }
        SimpleAdapter adapter = new SimpleAdapter(this,
            mList, R.layout.list_item, 
            new String[] {"content"}, 
            new int[] {R.id.list_text});
        mListView = (ListView) findViewById(R.id.list_view);
        mListView.setAdapter(adapter);
        mPosition = 0;
        mListView.setSelection(mPosition);

        mPrev = (Button) findViewById(R.id.btn_prev);
        mPrev.setOnClickListener(this);
        mNext = (Button) findViewById(R.id.btn_next);
        mNext.setOnClickListener(this);
    }

    public void onClick(View view)
    {
        if (view == mPrev && mPosition >= 0)
        {
            mListView.setSelection(mPosition);
            mPosition--;
        }
        else if (view == mNext && mPosition < mList.size())
        {
            mListView.setSelection(mPosition);
            mPosition++;
        }
    }
}

layout/list_item.xml (list item layout):

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:chess="http://schemas.android.com/apk/res/org.pengguang.chess"
    android:orientation="vertical"
    android:background="@color/list_bg"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">
<TextView
    android:id="@+id/list_text"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" />
</LinearLayout>

color/list_bg.xml (list item selector):

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

<item  
    android:state_selected="false"
    android:state_pressed="false" 
    android:drawable="@color/grey" />
<item 
    android:state_pressed="true" 
    android:drawable="@color/blue" />
<item 
    android:state_selected="true"
    android:state_pressed="false" 
    android:drawable="@color/red" />

</selector>

values/colors.xml (color file):

<?xml version="1.0" encoding="UTF-8"?>
<resources>
    <color name="blue">#0303ff</color>
    <color name="grey">#f7f7f7</color>
    <color name="red">#ff0000</color>
</resources>

Answer 1

Very easy way to highlight an item:

 lv.setItemChecked(ItemIndex,true);

but this item keeps selected(highlighted) until you set

 lv.setItemChecked(ItemIndex,false);

Answer 2

This is the intended behavior. Not sure why are you using the buttons for changing the selection?

You should possibly use single Choice Radiogroup which would show different selections.

Answer 3

I haven't try it.

listView.setOnItemSelectedListener(new OnItemSelectedListener() {

                public void onItemSelected(AdapterView<?> arg0, View arg1,
                        int arg2, long arg3) {
                    // TODO Auto-generated method stub
                    arg1.setSelected(true);
                }

                public void onNothingSelected(AdapterView<?> arg0) {
                    // TODO Auto-generated method stub

                }

            })