Android listview与adapter用法(BaseAdapter + getView)



Android listview与adapter用法

http://www.cnblogs.com/zhengbeibei/archive/2013/05/14/3078805.html

 



package com.example.listviewtest;

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

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.TextView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;

//import com.example.listviewtest.MyAdapter;

public class BaseAdapterTest extends Activity {

private ListView lv;
ArrayList<HashMap<String, Object>> listItem;

@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

lv = (ListView) findViewById(R.id.listview01);

MyAdapter mAdapter = new MyAdapter(this); //得到一个MyAdapter对象

lv.setAdapter(mAdapter); //为ListView绑定Adapter
/*为ListView添加点击事件*/
lv.setOnItemClickListener(new OnItemClickListener() {

@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Log.v("BaseAdapterTest", "你点击了ListView条目" + position);
}
});

}

/*添加一个得到数据的方法,方便使用*/
private ArrayList<HashMap<String, Object>> getData() {
ArrayList<HashMap<String, Object>> listItem = new ArrayList<HashMap<String,Object>>();

/*为动态数组添加数据*/
for (int i = 0; i < 30; i++) {
HashMap<String, Object> map = new HashMap<String, Object>();
map.put("ItemTitle", "第" + i + "行");
map.put("ItemText", "这是第" + i + "行");
listItem.add(map);
}

return listItem;
}

// 新建一个类继承BaseAdapter,实现视图与数据的绑定
private class MyAdapter extends BaseAdapter {

private LayoutInflater mInflater; //得到一个LayoutInfalter对象用来导入布局

public MyAdapter(Context context) {
this.mInflater = LayoutInflater.from(context);
}

@Override
public int getCount() {
return getData().size(); //返回数组的长度
}

@Override
public View getView(final int position, View convertView, ViewGroup parent) {
ViewHolder holder;
Log.v("BaseAdapterTest", "getView " + position + " " + convertView);

if (convertView == null) {
convertView = mInflater.inflate(R.layout.listitem, null);
holder = new ViewHolder();
/*得到各个控件的对象*/
holder.title = (TextView) convertView.findViewById(R.id.ItemTitle);
holder.text = (TextView) convertView.findViewById(R.id.ItemText);
holder.bt = (Button) convertView.findViewById(R.id.ItemButton); // to ItemButton

convertView.setTag(holder); //绑定ViewHolder对象
}
else {
holder = (ViewHolder) convertView.getTag(); //取出ViewHolder对象
}

/*设置TextView显示的内容,即我们存放在动态数组中的数据*/
holder.title.setText(getData().get(position).get("ItemTitle").toString());
holder.text.setText(getData().get(position).get("ItemText").toString());
/*为Button添加点击事件*/
holder.bt.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Log.v("BaseAdapterTest", "你点击了按钮" + position);
//打印Button的点击信息
}
});

return convertView;
}

@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;
}

}

/*存放控件 的ViewHolder*/
public final class ViewHolder {
public TextView title;
public TextView text;
public Button bt;
}

}