Android ListView实现品种分类效果

我们有时候会遇到这么一个情况。就是我在一个Listview里面需要显示的东西其实是有种类之分的。比如我要分冬天，夏天，秋天，春天，然后在这每个季节下面再去加载各自的条目数据。还有，比如我们的通讯录，我们需要按A，B，C这样的字母顺序分类然后显示。这个怎么实现呢？

下面我们不用ExpandableListView，而是只用ListView来实现这一显示效果。

MainActivity.java

package com.xzq.listviewadapter;

import android.app.Activity;
import android.os.Bundle;
import android.view.Window;
import android.widget.ListView;

public class MainActivity extends Activity {

private String[] string = { "A", "B", "C", "D", "E", "F", "G", "H", "I",
"J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V",
"W", "X", "Y", "Z" };

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.main);

ListView listview = (ListView) findViewById(R.id.listview);
MyCustomAdapter adapter = new MyCustomAdapter(this);

int size = string.length;
for (int i = 0; i < size; i++) {
adapter.addSeparatorItem(string[i]);
for (int k = 0; k < 5; k++) {
adapter.addItem("item " + k);
}
}
listview.setAdapter(adapter);
}
}

MyCustomAdapter.java

package com.xzq.listviewadapter;

import java.util.ArrayList;
import java.util.TreeSet;

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

public class MyCustomAdapter extends BaseAdapter {

private static final int TYPE_ITEM = 0;
private static final int TYPE_SEPARATOR = 1;
private static final int TYPE_MAX_COUNT = TYPE_SEPARATOR + 1;
private ArrayList<String> data = new ArrayList<String>();
private LayoutInflater inflater;
private TreeSet<Integer> set = new TreeSet<Integer>();

public MyCustomAdapter(Context context) {
inflater = LayoutInflater.from(context);
}

public void addItem(String item) {
data.add(item);
}

public void addSeparatorItem(String item) {
data.add(item);
set.add(data.size() - 1);
}

public int getItemViewType(int position) {
return set.contains(position)   TYPE_SEPARATOR : TYPE_ITEM;
}

@Override
public int getViewTypeCount() {
return TYPE_MAX_COUNT;
}

@Override
public int getCount() {
return data.size();
}

@Override
public Object getItem(int position) {
return data.get(position);
}

@Override
public long getItemId(int position) {
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
int type = getItemViewType(position);
if (convertView == null) {
holder = new ViewHolder();
switch (type) {
case TYPE_ITEM:
convertView = inflater.inflate(R.layout.item1, null);
holder.textView = (TextView) convertView
.findViewById(R.id.item1);
break;
case TYPE_SEPARATOR:
convertView = inflater.inflate(R.layout.item2, null);
holder.textView = (TextView) convertView
.findViewById(R.id.item2);
break;
}
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.textView.setText(data.get(position));
return convertView;
}

public static class ViewHolder {
public TextView textView;
}
}

main.xml

< xml version="1.0" encoding="utf-8" >
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#ffffff"
android:orientation="vertical" >

<ListView
android:id="@+id/listview"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello" />

</LinearLayout>

item1.xml

< xml version="1.0" encoding="utf-8" >
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#ffffff"
android:orientation="vertical" >

<TextView
android:id="@+id/item1"
android:layout_width="fill_parent"
android:layout_height="30dip"
android:gravity="center_vertical" />

</LinearLayout>

item2.xml

< xml version="1.0" encoding="utf-8" >
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<TextView
android:id="@+id/item2"
android:layout_width="fill_parent"
android:layout_height="30dip"
android:background="#3c4857"
android:gravity="center_vertical" />

</LinearLayout>