ImageSwitcher的简单使用

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

<ImageSwitcher
android:id="@+id/imageSwitcher"
android:layout_gravity="center"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >

<Button
android:id="@+id/btnPrevious"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:enabled="false"
android:text="上一张" />

<Button
android:id="@+id/btnNext"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:enabled="true"
android:text="下一张" />
</LinearLayout>

</LinearLayout>

package com.example.zz;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup.LayoutParams;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.ImageSwitcher;
import android.widget.ImageView;
import android.widget.ViewSwitcher.ViewFactory;

public class MainActivity extends Activity {
private ImageSwitcher imageSwitcher;
private Button btnPrevious;
private Button btnNext;
private int foot=0;
private int[] imgRes=new int[]{R.drawable.a,R.drawable.b,R.drawable.c,R.drawable.d,R.drawable.e,};

public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState); // 生命周期方法
super.setContentView(R.layout.activity_main); // 设置要使用的布局管理器
imageSwitcher=(ImageSwitcher)findViewById(R.id.imageSwitcher);
btnPrevious=(Button)findViewById(R.id.btnPrevious);
btnNext=(Button)findViewById(R.id.btnNext);

imageSwitcher.setFactory(new ViewFactory() {//设置转化工厂

@Override
public View makeView() {
ImageView imageView=new ImageView(MainActivity.this);
imageView.setBackgroundColor(0xFFFFFFFF);
imageView.setScaleType(ImageView.ScaleType.CENTER);//居中显示
imageView.setLayoutParams(new ImageSwitcher.LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.MATCH_PARENT));//定义组件
return imageView;
}
});
imageSwitcher.setImageResource(imgRes[foot++]);//初始化时显示，必须放在工厂后面，否则会报NullPointerException
imageSwitcher.setInAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_in));//设置动画
imageSwitcher.setOutAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_out));//设置动画
btnPrevious.setOnClickListener(new OnClickListener() {

public void onClick(View v) {
MainActivity.this.imageSwitcher.setImageResource(imgRes[foot--]);
MainActivity.this.checkBtnEnable();

}
});
btnNext.setOnClickListener(new OnClickListener() {

public void onClick(View v) {
MainActivity.this.imageSwitcher.setImageResource(imgRes[foot++]);
MainActivity.this.checkBtnEnable();

}
});

}

protected void checkBtnEnable() {//判断按钮可用状态
if(this.foot<this.imgRes.length-1){
this.btnNext.setEnabled(true);
}else{
this.btnNext.setEnabled(false);
}
if(this.foot==0){
this.btnPrevious.setEnabled(false);
}else {
this.btnPrevious.setEnabled(true);
}

}
}