Android第五天之ImageView图像视图

描述:往项目导入五张图片,通过点击两个Button上一张和下一张在Activity中切换图片的显示.

布局文件fragment_main.xml:

<LinearLayout 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:orientation="vertical"
android:padding="15dp" >
<ImageView
android:id="@+id/imageView1"
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_gravity="center"
android:src="@drawable/a1" />

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

<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="70dp"
android:text="下一张" />

<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="上一张" />

<TextView
android:id="@+id/text1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="0.21"
android:text="" />
</LinearLayout>

</LinearLayout>

MainActivity.java 文件:

package com.example.imageview;

import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;

public class MainActivity extends ActionBarActivity {

private ImageView imageview;
public int count = 0;
TextView text1;
//创建一个一维数组保存图片id
int[] imageid = {R.drawable.a1, R.drawable.a2,R.drawable.a3,
R.drawable.a4,R.drawable.a5,};

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_main);
//获取TextView的id
text1 = (TextView) findViewById(R.id.text1);
//获取ImageView的id
imageview = (ImageView) findViewById(R.id.imageView1);
//获取两个Button的id
Button btn1 = (Button) findViewById(R.id.button1);
Button btn2 = (Button) findViewById(R.id.button2);

//创建监听对象
ClickListener Listener = new ClickListener();
//监听两个Button
btn1.setOnClickListener(Listener);
btn2.setOnClickListener(Listener);
}

//创建监听方法
class ClickListener implements OnClickListener{

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.button1:
count = (count+1+imageid.length)%imageid.length;
text1.setText("第"+(count+1)+"张");
imageview.setImageResource(imageid[count]);
break;

case R.id.button2:
text1.setText("第"+count+"张");
count = (count-1+imageid.length)%imageid.length;
imageview.setImageResource(imageid[count]);
break;
}
}

}

}