自定义Adapter

--MainActivity代码

  1 package com.example.qqdemo;

  2 

  3 import java.util.ArrayList;

  4 import java.util.List;

  5 

  6 import android.os.Bundle;

  7 import android.app.Activity;

  8 import android.view.Gravity;

  9 import android.view.Menu;

 10 import android.view.View;

 11 import android.view.ViewGroup;

 12 import android.widget.BaseAdapter;

 13 import android.widget.ImageView;

 14 import android.widget.ListView;

 15 import android.widget.TextView;

 16 

 17 public class MainActivity extends Activity {

 18 

 19     private List<UserInfo> list = new ArrayList<UserInfo>();// 定义数据源

 20     private ListView mylistviwe;

 21 

 22     @Override

 23     protected void onCreate(Bundle savedInstanceState) {

 24         super.onCreate(savedInstanceState);

 25         setContentView(R.layout.activity_main);

 26         initlist();

 27         initview();

 28     }

 29 

 30     @Override

 31     public boolean onCreateOptionsMenu(Menu menu) {

 32         // Inflate the menu; this adds items to the action bar if it is present.

 33         getMenuInflater().inflate(R.menu.main, menu);

 34         return true;

 35     }

 36 

 37     private void initview() {

 38         mylistviwe = (ListView) findViewById(R.id.listview);

 39         mylistviwe.setAdapter(new Myadapter());//绑定适配器

 40     }

 41 

 42     /**

 43      * 2015-4-30 向数据源添加数据

 44      */

 45     private void initlist() {

 46 

 47         for (int i = 0; i < 20; i++) {

 48             UserInfo uif = new UserInfo();

 49             if (i % 2 == 0) {

 50                 uif.setImage(R.drawable.monkey );

 51                 uif.setMag("Hello");

 52                 uif.setFlag(true);

 53             } else {

 54                 uif.setImage(R.drawable.monkey1 );

 55                 uif.setMag("HI");

 56                 uif.setFlag(false);

 57             }

 58             list.add(uif);

 59         }

 60 

 61     }

 62 

 63     /**

 64      * 定义内部类 自定义适配器 实现数据绑定

 65      */

 66 

 67     private class Myadapter extends BaseAdapter {

 68 

 69         @Override

 70         public int getCount() {// 修改getCount()返回值为list的长度

 71 

 72             return list.size();// 返回数据的条数

 73         }

 74 

 75         @Override

 76         public Object getItem(int position) {// 修改getItem()list封装具体内容

 77 

 78             return list.get(position);// 获取item里面的内容

 79         }

 80 

 81         @Override

 82         public long getItemId(int position) { // 返回对应位置getItemId；

 83             // 返回对应位置getItemId；

 84 

 85             return position;// 返回item的位置

 86         }

 87 

 88         // 绑定数据getview->findviewbyid ->给控件添加数据

 89         @Override

 90         public View getView(int position, View convertView, ViewGroup parent) {

 91 

 92             // 手动生成View对象 查找XML中控件。

 93             // R.layout.item_xml-->找到XML控件

 94             // null-->是否把读取上来的view添加到容器当中

 95             View v = View.inflate(MainActivity.this, R.layout.item_xml, null);

 96             // 得到当先控件的ID

 97             ImageView leftimage = (ImageView) v.findViewById(R.id.leftimage);

 98             ImageView rigtimage = (ImageView) v.findViewById(R.id.rigtimage);

 99             TextView tvshow = (TextView) v.findViewById(R.id.mytextview);

100             UserInfo muif = list.get(position);// 获取到item里面的内容

101 

102             // 将item添加到ListView中

103             if (muif.isFlag()) {

104                 rigtimage.setVisibility(View.GONE);

105                 leftimage.setVisibility(View.VISIBLE);

106                 leftimage.setImageResource(muif.getImage());

107                 tvshow.setText(muif.getMag());

108                 tvshow.setGravity(Gravity.LEFT);

109 

110             } else {

111                 rigtimage.setVisibility(View.VISIBLE);

112                 leftimage.setVisibility(View.GONE);

113                 leftimage.setImageResource(muif.getImage());

114                 tvsh

115 

116 

117 

118 

119 ow.setText(muif.getMag());

120                 tvshow.setGravity(Gravity.RIGHT);

121 

122             }

123             return v;

124         }

125 

126     }

127 

128 }

 

 1 package com.example.qqdemo;  2 /**  3  * 封装UserInfo对象  4  * @author wenfei  5 */  6 public class UserInfo {  7 private int image;  8 private String mag;  9 private boolean flag; 10 11 12 public int getImage() { 13 return image; 14  } 15 public void setImage(int image) { 16 this.image = image; 17  } 18 public String getMag() { 19 return mag; 20  } 21 public void setMag(String mag) { 22 this.mag = mag; 23  } 24 public boolean isFlag() { 25 return flag; 26  } 27 public void setFlag(boolean flag) { 28 this.flag = flag; 29  } 30 31 32 }

--XML文件

 1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

 2     xmlns:tools="http://schemas.android.com/tools"

 3     android:layout_width="match_parent"

 4     android:layout_height="match_parent"

 5     tools:context=".MainActivity" >

 6 

 7     <ListView

 8         android:id="@+id/listview"

 9         android:layout_width="match_parent"

10         android:layout_height="match_parent" />

11 

12 </LinearLayout>

 1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

 2     xmlns:tools="http://schemas.android.com/tools"

 3     android:layout_width="match_parent"

 4     android:layout_height="match_parent"

 5     android:orientation="vertical"

 6     tools:context=".MainActivity" >

 7 

 8     <RelativeLayout

 9         android:layout_width="match_parent"

10         android:layout_height="50dp" >

11 

12         <ImageView

13             android:id="@+id/leftimage"

14             android:layout_width="wrap_content"

15             android:layout_height="wrap_content"

16             android:layout_centerVertical="true"

17             android:src="@drawable/monkey" />

18 

19         <TextView

20             android:id="@+id/mytextview"

21             android:layout_width="wrap_content"

22             android:layout_height="wrap_content"

23             android:layout_centerVertical="true"

24             android:layout_toLeftOf="@+id/rigtimage"

25             android:layout_toRightOf="@+id/leftimage"

26             android:gravity="right"

27             android:text="我来了" />

28 

29         <ImageView

30             android:id="@+id/rigtimage"

31             android:layout_width="wrap_content"

32             android:layout_height="wrap_content"

33             android:layout_alignParentRight="true"

34             android:layout_centerVertical="true"

35             android:src="@drawable/monkey1" />

36     </RelativeLayout>

37 

38 </LinearLayout>