安卓天天练练（七）轮播图

<AbsoluteLayout 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"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.narumi.android_9_1.MainActivity" >

<ImageView
android:id="@+id/imageView1"
android:layout_width="105dp"
android:layout_height="105dp"
android:layout_x="100dp"
android:layout_y="36dp"
android:src="@drawable/ic_launcher" />

<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_x="41dp"
android:layout_y="160dp"
android:text="@string/prev_btn" />

<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_x="184dp"
android:layout_y="160dp"
android:=""
android:text="@string/next_btn" />

</AbsoluteLayout>

package com.narumi.android_9_1;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends Activity {
ImageView iv;
Button btnPrev;
Button btnNext;

int[] imgId = {
R.drawable.p01,
R.drawable.p02,
R.drawable.p03,
R.drawable.p04,
R.drawable.p05,
R.drawable.p06,
};

int currImgId = 0;

private View.OnClickListener mylistener = new View.OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if(v == btnPrev){
currImgId = (currImgId - 1 + imgId.length)%imgId.length;
iv.setImageResource(imgId[currImgId]);
}else if(v == btnNext){
currImgId = (currImgId+1)%imgId.length;
iv.setImageResource(imgId[currImgId]);
}
}
};

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
iv = (ImageView)findViewById(R.id.imageView1);

btnPrev = (Button)findViewById(R.id.button1);

btnNext = (Button)findViewById(R.id.button2);

btnPrev.setOnClickListener(mylistener);

btnNext.setOnClickListener(mylistener);
}

}