android 自定义adapter

    Adapter是用来帮助填充数据的中间桥梁，比如通过它将数据填充到ListView, GridView, Gallery等，而android的adapter又有很多种（ArrayAdapter, BaseAdapter, CursorAdapter, HeaderViewListAdapter, ListAdapter, ResourceCursorAdapter, SimpleAdapter, SimpleCursorAdapter, SpinnerAdapter, WrapperListAdapter） 今天挑选其中几种做笔记，方便日后温故。

1用BaseAdapter实现如下效果：

Item  的activity_main.xml文件：

greens_listview.xml文件：

Activity代码：

package com.example.adapter;

import android.app.Activity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;

public class MainActivity extends Activity {

	private ListView lsitview_greens;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.greens_listview);	
		
		MyApater adapter = new MyApater();
		lsitview_greens  = (ListView) findViewById(R.id.listview_greens);
		lsitview_greens.setAdapter(adapter);
		
		
	}

	//自定义Adapter
	class MyApater extends BaseAdapter{
		
		//用于显示菜品的图片
		int[] images = {R.drawable.safe,R.drawable.safe,R.drawable.safe,R.drawable.safe,R.drawable.safe,R.drawable.safe,R.drawable.safe,R.drawable.safe,R.drawable.safe};
		//用于显示菜名
		String[]  name = new String[]{
			"宫保鸡丁","糖醋排骨","麻婆豆腐","红烧鱼","回锅肉","辣椒炒肉","醋溜土豆丝","大蒜腊牛肉","红烧排骨"
		};
		//用于显示价格
		String[] price = new String[]{
			"32￥","22￥","15￥","94￥","45￥","15￥","20￥","45￥","85￥"	
		};
		@Override
		public int getCount() {
			// TODO Auto-generated method stub
			return name.length;
		}

		@Override
		public Object getItem(int arg0) {
			// TODO Auto-generated method stub
			return null;
		}

		@Override
		public long getItemId(int position) {
			// TODO Auto-generated method stub
			return position;
		}

		@Override
		public View getView(int position, View convertView, ViewGroup parent) {
			if(convertView == null){
				//根据布局文件获取View返回值
				convertView = LayoutInflater.from(getApplicationContext()).inflate(R.layout.activity_main, null);				
			}
			ImageView imageview = (ImageView) convertView.findViewById(R.id.im_greens);
			TextView greens_name = (TextView) convertView.findViewById(R.id.tv_greens);
			TextView greens_price = (TextView) convertView.findViewById(R.id.tv_price_2);
			
			imageview.setImageResource(images[position]);
			greens_name.setText(name[position]);
			greens_price.setText(price[position]);
			return convertView;
		}
		
	}
}

2 通过BaseAdapter填充GridView实现九宫格的效果：

Item的mainscreen_item.xml文件：

activity_main.xml：

MainUiAdapter：是自定义的一个adapter类，在MainActivity中调用，它的主要作用是填充所需数据

package com.iponeguardian.adapter;

import com.example.iponeguardian.R;

import android.content.Context;
import android.content.SharedPreferences;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

public class MainUiAdapter extends BaseAdapter {

	private Context context;
	private LayoutInflater inflater;   //布局文件填充器
	private static ImageView imageView;//显示图片的控件
	private static TextView textView;  //显示文字的控件
	private SharedPreferences sp;      //持久化数据
	
	//程序九宫格主界面所需图片以及文字
	private String[] name ={"手机防盗","通讯卫士","软件管理","任务管理","流量管理","手机杀毒","系统优化","高级工具","设置中心"};  
	private static int[] icon = {R.drawable.widget09,R.drawable.widget02,R.drawable.widget01,R.drawable.widget07,
		R.drawable.widget05,R.drawable.widget04,R.drawable.widget06,R.drawable.widget03,R.drawable.widget08};
	
	public MainUiAdapter(Context context) {		
		this.context = context;
		inflater = LayoutInflater.from(context);
		sp = context.getSharedPreferences("config", context.MODE_PRIVATE);
	}
	@Override
	public int getCount() {
		// TODO Auto-generated method stub
		return name.length;
	}

	@Override
	public Object getItem(int position) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public long getItemId(int position) {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public View getView(int position, View contentview, ViewGroup parent) {

		//得到布局文件
		View view = inflater.inflate(R.layout.mainscreen_item, null);
		imageView = (ImageView) view.findViewById(R.id.imageView_mainscreen_Item);
		textView = (TextView) view.findViewById(R.id.textView_mainscreen_Item);
		imageView.setImageResource(icon[position]);
		textView.setText(name[position]);
		if(position == 0){
			String name = sp.getString("lost_name", null);
			if(name!=null){
				textView.setText(name);
			}
		}
		return view;
	}

}

MainActivity,程序入口(里面有些内容没有做修改)：

package com.iponeguardian.ui;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.content.Context;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.AdapterView.OnItemLongClickListener;
import android.widget.EditText;
import android.widget.GridView;
import android.widget.TextView;
import android.widget.Toast;

import com.example.iponeguardian.R;
import com.iponeguardian.adapter.MainUiAdapter;
import com.iponeguardian.utile.UpdateManagerTest;

public class MainActivity extends Activity implements OnItemClickListener{

	private GridView gv_main;
	private MainUiAdapter adapter;
	private SharedPreferences preferences;  //用来持久化一些配置信息
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		
		preferences = this.getSharedPreferences("config", Context.MODE_PRIVATE);		
		adapter = new MainUiAdapter(this);
		gv_main = (GridView)this.findViewById(R.id.gv_main);
		gv_main.setAdapter(adapter);
		
		//设置条目点击事件
		gv_main.setOnItemClickListener(this);
		//为第一个条目设置长按的点击事件
		gv_main.setOnItemLongClickListener(new OnItemLongClickListener() {
			@Override
			public boolean onItemLongClick(AdapterView parent, final View view,
					int position, long id) {
				if(position==0){
				AlertDialog.Builder builder = new Builder(MainActivity.this); 
				builder.setTitle("重命名");
				builder.setMessage("请输入要更改的名称");
				final EditText editText = new EditText(MainActivity.this);
				editText.setText("请输入文本");
				builder.setView(editText);
				builder.setPositiveButton("确定", new OnClickListener() {
					
					public void onClick(DialogInterface dialog, int which) {
						String name = editText.getText().toString().trim();
						if("".equals(name)){
							Toast.makeText(getApplicationContext(), "内容不能为空", 1).show();
							return ;
						}else{
							//新建一个文件，持久化数据，用来存储更改的名字
							Editor editor = preferences.edit();
							editor.putString("lost_name", name);
							editor.commit();
							//设置新的名字
							TextView textView = (TextView) view.findViewById(R.id.textView_mainscreen_Item);
							textView.setText(name);
						}
					}
				});
				builder.setNegativeButton("取消", new OnClickListener() {
					
					@Override
					public void onClick(DialogInterface dialog, int which) {
					
					}
				});
				builder.create().show();
				}
				return false;
			}
		});
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		UpdateManagerTest managerTest = new UpdateManagerTest(getApplicationContext());
		managerTest.checkUpdate();
		return false;
		
	}

	/**
	 * 点击某一个条目调用的方法
	 * parent:gradView
	 * view:  当前被点击的条目
	 * position：点击条目所对应的位置
	 * id: 行号
	 */
	@Override
	public void onItemClick(AdapterView parent, View view, int position, long id) {
		// TODO Auto-generated method stub
		
		switch (position) {
		case 0:
			Intent lostProtectedIntent = new Intent(MainActivity.this,LostProtectedActivity.class);
			startActivity(lostProtectedIntent);
			break;

		//点击通讯卫士
		case 1:
			Intent callSmsIntent = new Intent(MainActivity.this,CallSmsActivity.class);
			startActivity(callSmsIntent);
			break;	
		//点击高级工具
		case 7:
			Intent atoolsintent = new Intent(MainActivity.this,AtoolsActivity.class);
			startActivity(atoolsintent);
		break;
		}
	}

}