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

package org.crazyit.helloworld;import android.os.Bundle;import android.app.Activity;import android.view.DragEvent;import android.view.Menu;import android.view.View;import android.view.View.OnDragListener;import android.widget.Button;import android.widget.ImageView;import android.widget.LinearLayout;import android.widget.TextView;public class MainActivity extends Activity {    //定义一个访问图片的数组    int[] images = new int[]{            R.drawable.ic_launcher,            R.drawable.aaa,            R.drawable.asd,            R.drawable.sss                };    int currentImg = 0;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        //获取线性布局容器        LinearLayout main = (LinearLayout)findViewById(R.id.root);        //程序创建iamgeview组件        final ImageView image = new ImageView(this);        //添加进布局        main.addView(image);        //初始化显示第一张照片        image.setImageResource(images[0]);        image.setOnClickListener(new View.OnClickListener(){            public void onClick(View v)            {                if (currentImg >=4)                {                    currentImg = -1;                }                image.setImageResource(images[++currentImg]);            }                    });    }}