GridView的应用一

主要代码：

MainActivitiy:

package com.example.gridview;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.SimpleAdapter;

        
    
public class MainActivity extends Activity {
    private GridView smallImageGrid;
    private  ImageView  showImage;
    private int[] pics;
    
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        //查找组件
        smallImageGrid=(GridView) this.findViewById(R.id.imagelist);
        showImage=(ImageView) this.findViewById(R.id.imageshow);
        //实例化图片数组
        pics=new int[]{R.drawable.a,R.drawable.b,R.drawable.c,R.drawable.d,R.drawable.e,R.drawable.f};
        List<Map<String,Object>> pic_items=new ArrayList<Map<String,Object>>();
        for(int pic_id:pics){
         Map<String,Object> item=new HashMap<String, Object>();
         item.put("pic",pic_id);
         pic_items.add(item);
        }
        SimpleAdapter adapter=new SimpleAdapter(this,pic_items,R.layout.grid,new String[]{"pic"},new int[]{R.id.smallImage});
        smallImageGrid.setAdapter(adapter);
        
        showImage.setImageResource(pics[0]);
        
        smallImageGrid.setOnItemClickListener(new GridViewHandler());
    }
    
    public class GridViewHandler implements OnItemClickListener{
  public void onItemClick(AdapterView<?> adapter, View view, int position,
    long id) {
   showImage.setImageResource(pics[position]);
   
  }
     
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
    
    
}

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

    <GridView
        android:id="@+id/imagelist"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:horizontalSpacing="20dp"
        android:numColumns="3"
        android:verticalSpacing="10dp" >
    </GridView>

    <ImageView
        android:id="@+id/imageshow"
        android:layout_marginTop="20dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:adjustViewBounds="true"
        />
</LinearLayout>

grid.xml

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

    <ImageView
        android:id="@+id/smallImage"
        android:layout_width="80dp"
        android:layout_height="50dp"/>
</LinearLayout>

strings.xml

<resources>

    <string name="app_name">GridView组件的使用</string>
    <string name="hello_world">        Hello world!</string>
    <string name="menu_settings">Settings</string>
    <string name="title_activity_main">图片展示</string>

</resources>

主要运行图：