一手遮天 Android - view（ListView）: ListView 的多布局（不同的 item 使用不同的项模板）
一手遮天 Android - view（ListView）: ListView 的多布局（不同的 item 使用不同的项模板）
示例如下:
/view/listview/ListViewDemo7.java
/**
* ListView 的多布局（不同的 item 使用不同的项模板）
*
* 适配器中包含了数据和项模板
*/
package com.webabcd.androiddemo.view.listview;
import android.content.Context;
import androidx.appcompat.app.AppCompatActivity;
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;
import com.webabcd.androiddemo.R;
import java.util.ArrayList;
import java.util.List;
public class ListViewDemo7 extends AppCompatActivity {
// 第 1 种布局类别：左对齐
private static final int TYPE_LEFT = 0;
// 第 2 种布局类别：右对齐
private static final int TYPE_RIGHT = 1;
private ListView _listView1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_view_listview_listviewdemo7);
_listView1 = (ListView) findViewById(R.id.listView1);
sample();
}
private void sample() {
// 构造数据
List<MyData> myDataList = new ArrayList<MyData>();
for (int i = 0; i < 100; i++) {
myDataList.add(new MyData(R.drawable.img_sample_son, "name " + i, "comment " + i));
}
MyAdapter myAdapter = new MyAdapter(myDataList, this);
_listView1.setAdapter(myAdapter);
}
// 自定义实体类
class MyData {
private int _logoId;
private String _name;
private String _comment;
public MyData() {
}
public MyData(int logoId, String name, String comment) {
this._logoId = logoId;
this._name = name;
this._comment = comment;
}
public int getLogoId() {
return _logoId;
}
public String getName() {
return _name;
}
public String getComment() {
return _comment;
}
public void setLogoId(int logoId) {
this._logoId = logoId;
}
public void setName(String name) {
this._name = name;
}
public void setComment(String comment) {
this._comment = comment;
}
}
// 自定义 BaseAdapter
class MyAdapter extends BaseAdapter {
private List<MyData> _myDataList;
private Context _context;
public MyAdapter(List<MyData> myDataList, Context context) {
this._myDataList = myDataList;
this._context = context;
}
// 需要呈现的 item 的总数
@Override
public int getCount() {
return _myDataList.size();
}
// 返回指定索引位置的 item 的对象
@Override
public Object getItem(int position) {
return _myDataList.get(position);
}
// 返回指定索引位置的 item 的 id
@Override
public long getItemId(int position) {
return position;
}
// 返回指定索引位置的 item 的布局类别
@Override
public int getItemViewType(int position) {
if (position % 2 == 0) {
return TYPE_LEFT;
} else {
return TYPE_RIGHT;
}
}
// 布局类别的数量
@Override
public int getViewTypeCount() {
return 2;
}
// 每构造一个 item 就会调用一次 getView() 来获取这个 item 的 view
// 每次绘制 item 都会调用 getView()
@Override
public View getView(int position, View convertView, ViewGroup parent) {
int type = getItemViewType(position);
ViewHolder1 holder1 = null;
ViewHolder2 holder2 = null;
if (convertView == null) {
if (type == TYPE_LEFT) { // 使用 TYPE_LEFT 布局类别的项模板
convertView = LayoutInflater.from(_context).inflate(R.layout.item_view_listview_listviewdemo7_1, parent, false);
holder1 = new ViewHolder1();
holder1.imgLogo = (ImageView) convertView.findViewById(R.id.imgLogo);
holder1.txtName = (TextView) convertView.findViewById(R.id.txtName);
holder1.txtComment = (TextView) convertView.findViewById(R.id.txtComment);
convertView.setTag(holder1);
} else if (type == TYPE_RIGHT) { // 使用 TYPE_RIGHT 布局类别的项模板
convertView = LayoutInflater.from(_context).inflate(R.layout.item_view_listview_listviewdemo7_2, parent, false);
holder2 = new ViewHolder2();
holder2.imgLogo = (ImageView) convertView.findViewById(R.id.imgLogo);
holder2.txtName = (TextView) convertView.findViewById(R.id.txtName);
holder2.txtComment = (TextView) convertView.findViewById(R.id.txtComment);
convertView.setTag(holder2);
}
} else {
if (type == TYPE_LEFT) {
holder1 = (ViewHolder1) convertView.getTag();
} else if (type == TYPE_RIGHT) {
holder2 = (ViewHolder2) convertView.getTag();
}
}
if (type == TYPE_LEFT) {
holder1.imgLogo.setBackgroundResource(_myDataList.get(position).getLogoId());
holder1.txtName.setText(_myDataList.get(position).getName());
holder1.txtComment.setText(_myDataList.get(position).getComment());
} else if (type == TYPE_RIGHT) {
holder2.imgLogo.setBackgroundResource(_myDataList.get(position).getLogoId());
holder2.txtName.setText(_myDataList.get(position).getName());
holder2.txtComment.setText(_myDataList.get(position).getComment());
}
return convertView;
}
class ViewHolder1 {
ImageView imgLogo;
TextView txtName;
TextView txtComment;
}
class ViewHolder2 {
ImageView imgLogo;
TextView txtName;
TextView txtComment;
}
}
}
/layout/activity_view_listview_listviewdemo7.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<ListView
android:id="@+id/listView1"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</LinearLayout>
/layout/item_view_listview_listviewdemo7_1.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="10dp"
android:orientation="horizontal">
<ImageView
android:id="@+id/imgLogo"
android:layout_width="64dp"
android:layout_height="64dp" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:id="@+id/txtName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#1D1D1D"
android:textSize="24sp" />
<TextView
android:id="@+id/txtComment"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#B4B4B4"
android:textSize="14sp" />
</LinearLayout>
</LinearLayout>
/layout/item_view_listview_listviewdemo7_2.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="10dp"
android:paddingRight="10dp"
android:gravity="right"
android:orientation="horizontal">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:id="@+id/txtName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#1D1D1D"
android:textSize="24sp" />
<TextView
android:id="@+id/txtComment"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#B4B4B4"
android:textSize="14sp" />
</LinearLayout>
<ImageView
android:id="@+id/imgLogo"
android:layout_width="64dp"
android:layout_height="64dp" />
</LinearLayout>
