安卓自写Adapter

代码：

package com.example.ouradapter;

import android.app.ListActivity;
import android.content.Context;
import android.graphics.Color;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.TableLayout.LayoutParams;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends ListActivity {
    private String[] mListTitle = { "姓名", "性别", "年龄", "居住地","邮箱"};
    private String[] mListStr = { "雨松MOMO", "男", "", "北京",
        "xuanyusong@gmail.com" };
    ImageView iamge = null;
    TextView title = null;
    TextView text = null;
    ListView mListView = null;
//    RelativeLayout rl=(RelativeLayout)this.findViewById(R.id.rl);
    MyListAdapter myAdapter = null;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
    mListView = getListView();
    myAdapter = new MyListAdapter(this);
    setListAdapter(myAdapter);
    mListView.setOnItemClickListener(new OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int position,
            long id) {
        View v=adapterView.getChildAt(position);
        v.setBackgroundColor(Color.RED);
        Toast.makeText(MainActivity.this,"您选择了" + mListStr[position], Toast.LENGTH_LONG).show();
        }
    });  

//    View v=LayoutInflater.from(this).inflate(R.layout.activity_main, null);
//    iamge = (ImageView)v.findViewById(R.id.color_image);
//    title =(TextView)v.findViewById(R.id.color_title);
//    text= (TextView)v.findViewById(R.id.color_text);
//    title.setText(mListTitle[1]);
//    text.setText("123456789");
//    iamge.setImageResource(R.drawable.ic_launcher);
//    this.addContentView(v,new LinearLayout.LayoutParams(
//            LinearLayout.LayoutParams.WRAP_CONTENT,
//            LinearLayout.LayoutParams.WRAP_CONTENT));
    super.onCreate(savedInstanceState);
    }  

    public class MyListAdapter extends BaseAdapter {
        private Context mContext;
        private int[] colors = new int[] {Color.BLUE, Color.GREEN,Color.YELLOW,Color.WHITE };
        public MyListAdapter(Context context) {
            mContext = context;
        }  

        public int getCount() {
            return mListStr.length;
        }  

//        @Override
//        public boolean areAllItemsEnabled() {
//            return false;
//        }
        @Override
        public Object getItem(int position) {
            return position;
        }
        @Override
        public long getItemId(int position) {
            return position;
        }
       @Override
        public View getView(int position, View convertView, ViewGroup parent) {  

            if (convertView == null) {
            convertView = LayoutInflater.from(mContext).inflate(R.layout.activity_main, null);
            iamge = (ImageView) convertView.findViewById(R.id.color_image);
            title =(TextView) convertView.findViewById(R.id.color_title);
            text= (TextView) convertView.findViewById(R.id.color_text);
            }
            int colorPos = position % colors.length;
            convertView.setBackgroundColor(colors[colorPos]);
            title.setText(mListTitle[position]);
            text.setText(mListStr[position]);
             iamge.setImageResource(R.drawable.ic_launcher);
            return convertView;
       }

    }
}  

listView在一开始绘制的时候首先会调用getCout()方法得到绘制次数 ，然后会实例化自己定义的BaseAdapter通过getView()方法一层一层绘制ListView,所以我们可以在这里面根据position(当前绘制的ID)来任意的修改绘制的内容。结果：

ArrayAdapter是BaseAdapter的子类，ArrayAdapter不仅具有BaseAdapter的所有方法还自定义了一些新的方法来处理列表项，所以单纯的从功能能上来讲ArrayAdapter远远强与BaseAdapter，如果是绘制一些数量比较少的列表建议使用BaseAdapter 如果绘制一些比较复杂的列表项 并且列表项很多的 建议使用ArrayAdapter。