Android控件之GridView探究

GridView是一项显示二维的viewgroup，可滚动的网格。一般用来显示多张图片。

以下模拟九宫图的实现，当鼠标点击图片时会进行相应的跳转链接。

目录结构

main.xml布局文件，存放GridView控件

<?xml version="1.0" encoding="utf-8"?>
<!-- 
android:numColumns="auto_fit" ，GridView的列数设置为自动 
android:columnWidth="90dp"，每列的宽度，也就是Item的宽度
android:stretchMode="columnWidth"，缩放与列宽大小同步
android:verticalSpacing="10dp"，两行之间的边距，如：行一(NO.0~NO.2)与行二(NO.3~NO.5)间距为10dp
android:horizontalSpacing="10dp"，两列之间的边距
 -->
<GridView xmlns:android="http://schemas.android.com/apk/res/android" 
    android:id="@+id/gridview"
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent"
    android:numColumns="auto_fit"
    android:verticalSpacing="10dp"
    android:horizontalSpacing="10dp"
    android:columnWidth="90dp"
    android:stretchMode="columnWidth"
    android:gravity="center"
/>

night_item.xml布局文件，存放显示控件

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_height="wrap_content" 
    android:paddingBottom="4dip"
    android:layout_width="fill_parent">
    <ImageView android:layout_height="wrap_content"
        android:layout_width="wrap_content"
        android:layout_centerHorizontal="true"
        android:id="@+id/itemImage" >
    </ImageView>
    <TextView android:layout_width="wrap_content"
        android:layout_below="@+id/itemImage"
        android:layout_height="wrap_content" 
        android:text="TextView01"
        android:layout_centerHorizontal="true" 
        android:id="@+id/itemText">
    </TextView>
</RelativeLayout>

strings.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="hello">Hello World, GvActivity!</string>
    <string name="app_name">九宫图</string>
    <string name="test_name1">跳转到TestActivity1</string>
    <string name="test_name2">跳转到TestActivity2</string>
    <string name="test_name3">跳转到TestActivity3</string>
</resources>

清单文件

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.ljq.gv"
      android:versionCode="1"
      android:versionName="1.0">
    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".GvActivity"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".TestActivity1" android:label="@string/test_name1"/>
        <activity android:name=".TestActivity2" android:label="@string/test_name2"/>
        <activity android:name=".TestActivity3" android:label="@string/test_name3"/>
    </application>
    <uses-sdk android:minSdkVersion="7" />

</manifest> 

跳转类TestActivity1、TestActivity2、TestActivity3

package com.ljq.gv;

import android.app.Activity;
import android.os.Bundle;

public class TestActivity1 extends Activity {
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //setContentView(R.layout.main);
    }
}

package com.ljq.gv;

import android.app.Activity;
import android.os.Bundle;

public class TestActivity2 extends Activity {
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //setContentView(R.layout.main);
    }
}

package com.ljq.gv;

import android.app.Activity;
import android.os.Bundle;

public class TestActivity3 extends Activity {
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //setContentView(R.layout.main);
    }
}

类GvActivity

package com.ljq.gv;

import java.util.ArrayList;
import java.util.HashMap;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.GridView;
import android.widget.SimpleAdapter;
import android.widget.Toast;
import android.widget.AdapterView.OnItemClickListener;

public class GvActivity extends Activity {
    private String texts[] = null;
    private int images[] = null;
    
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        images=new int[]{R.drawable.p1, R.drawable.p2,
                R.drawable.p3, R.drawable.p4, 
                R.drawable.p5,R.drawable.p6, 
                R.drawable.p7,R.drawable.p8};
        texts = new String[]{ "宫式布局1", "宫式布局2",
                "宫式布局3", "宫式布局4", 
                "宫式布局5", "宫式布局6",
                "宫式布局7", "宫式布局8"};

        GridView gridview = (GridView) findViewById(R.id.gridview);
        ArrayList<HashMap<String, Object>> lstImageItem = new ArrayList<HashMap<String, Object>>();
        for (int i = 0; i < 8; i++) {
            HashMap<String, Object> map = new HashMap<String, Object>();
            map.put("itemImage", images[i]);
            map.put("itemText", texts[i]);
            lstImageItem.add(map);
        }
        
        SimpleAdapter saImageItems = new SimpleAdapter(this, 
                lstImageItem,// 数据源
                R.layout.night_item,// 显示布局
                new String[] { "itemImage", "itemText" }, 
                new int[] { R.id.itemImage, R.id.itemText }); 
        gridview.setAdapter(saImageItems);
        gridview.setOnItemClickListener(new ItemClickListener());
    }

    class ItemClickListener implements OnItemClickListener {
        /**
         * 点击项时触发事件
         * 
         * @param parent  发生点击动作的AdapterView
         * @param view 在AdapterView中被点击的视图(它是由adapter提供的一个视图)。
         * @param position 视图在adapter中的位置。
         * @param rowid 被点击元素的行id。
         */
        public void onItemClick(AdapterView<?> parent, View view, int position, long rowid) {
            HashMap<String, Object> item = (HashMap<String, Object>) parent.getItemAtPosition(position);
            //获取数据源的属性值
            String itemText=(String)item.get("itemText");
            Object object=item.get("itemImage");
            Toast.makeText(GvActivity.this, itemText, Toast.LENGTH_LONG).show();
            
            //根据图片进行相应的跳转
            switch (images[position]) {
            case R.drawable.p1:
                startActivity(new Intent(GvActivity.this, TestActivity1.class));//启动另一个Activity
                finish();//结束此Activity，可回收
                break;
            case R.drawable.p2:
                startActivity(new Intent(GvActivity.this, TestActivity2.class));
                finish();
                break;
            case R.drawable.p3:
                startActivity(new Intent(GvActivity.this, TestActivity3.class));
                finish();
                break;
            }
            
        }
    }
}

运行结果