Android常用控件之GridView使用BaseAdapter

我们可以为GridView添加自定义的Adapter，首先看下用自定义Adapter的显示效果

在布局文件main.xml文件中定义一个GridView控件

<RelativeLayout 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"    tools:context=".MainActivity" >    <GridView        android:id="@+id/gridView"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:numColumns="4"        android:stretchMode="columnWidth" >    </GridView></RelativeLayout>

要使用BaseAdapter首先定义一个类继承BaseAdapter，并重写几个方法

package com.example.gridviewadapterdemo;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.view.ViewGroup;import android.widget.AdapterView;import android.widget.BaseAdapter;import android.widget.GridView;import android.widget.ImageView;import android.widget.AdapterView.OnItemClickListener;public class MainActivity extends Activity {private GridView gridView = null;private int[] imageId = new int[] { R.drawable.img01, R.drawable.img02,R.drawable.img03, R.drawable.img04, R.drawable.img05,R.drawable.img06, R.drawable.img07, R.drawable.img08,R.drawable.img09, R.drawable.img10, R.drawable.img11,R.drawable.img12, }; // 定义并初始化保存图片id的数组@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);gridView = (GridView) findViewById(R.id.gridView);GridViewAdapter gridViewAdapter = new GridViewAdapter();gridView.setAdapter(gridViewAdapter);// 为GridView设定监听器gridView.setOnItemClickListener(new gridViewListener());}class gridViewListener implements OnItemClickListener {@Overridepublic void onItemClick(AdapterView<?> arg0, View arg1, int arg2,long arg3) {// TODO Auto-generated method stubSystem.out.println("arg2 = " + arg2); // 打印出点击的位置}}private class GridViewAdapter extends BaseAdapter {@Overridepublic View getView(int position, View convertView, ViewGroup parent) {ImageView imageview; // 声明ImageView的对象if (convertView == null) {imageview = new ImageView(MainActivity.this); // 实例化ImageView的对象imageview.setScaleType(ImageView.ScaleType.CENTER_INSIDE); // 设置缩放方式imageview.setPadding(5, 0, 5, 0); // 设置ImageView的内边距} else {imageview = (ImageView) convertView;}imageview.setImageResource(imageId[position]); // 为ImageView设置要显示的图片return imageview; // 返回ImageView}/* * 功能：获得当前选项的ID *  * @see android.widget.Adapter#getItemId(int) */@Overridepublic long getItemId(int position) {//System.out.println("getItemId = " + position);return position;}/* * 功能：获得当前选项 *  * @see android.widget.Adapter#getItem(int) */@Overridepublic Object getItem(int position) {return position;}/* * 获得数量  *  * @see android.widget.Adapter#getCount() */@Overridepublic int getCount() {return imageId.length;}}}

样例代码

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