【Android】Activity类及其子类：LauncherActivity、PreferenceActivity和ExpandableListActivity

Activity类及其子类类图：



下面的例子展示了LauncherActivity、PreferenceActivity和ExpandableListActivity的简单用法。

LauncherActivityTest.java：

package com.zzj.ui.activitydemo;

import android.app.LauncherActivity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.util.Log;
import android.widget.ArrayAdapter;

public class LauncherActivityTest extends LauncherActivity {

private String[] data = { "参数设置", "选择产品" };
private Class<?>[] classes = { PreferenceActivityTest.class,
ExpandableListActivityTest.class };

@Override
protected void onCreate(Bundle icicle) {
super.onCreate(icicle);

ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, data);
setListAdapter(adapter);
}

@Override
protected Intent intentForPosition(int position) {
return new Intent(this, classes[position]);
}

/**
* 获取PreferenceActivity设置的参数
*/
@Override
protected void onResume() {
super.onResume();
SharedPreferences sharedPreferences = PreferenceManager
.getDefaultSharedPreferences(this);
boolean flyMode = sharedPreferences.getBoolean("flyMode", false);
String editText = sharedPreferences.getString("editText1", "");
String wlanSleep = sharedPreferences.getString("wlanSleep", "");
boolean keyDownVoice = sharedPreferences.getBoolean("keyDownVoice",
false);
String ringtone = sharedPreferences.getString("ringtone", "");
String alarm = sharedPreferences.getString("alarm", "");
String notification = sharedPreferences.getString("notification", "");
String all = sharedPreferences.getString("all", "");

Log.d("flyMode", String.valueOf(flyMode));
Log.d("editText1", editText);
Log.d("wlanSleep", wlanSleep);
Log.d("keyDownVoice", String.valueOf(keyDownVoice));
Log.d("ringtone", ringtone);
Log.d("alarm", alarm);
Log.d("notification", notification);
Log.d("all", all);
}
}

LauncherActivity不需要布局文件。重写intentForPosition(int position)方法，点击每个列表项的时候，会回调该方法，通过返回的Intent跳转至Activity。

PreferenceActivityTest.java：

package com.zzj.ui.activitydemo;

import android.os.Bundle;
import android.preference.CheckBoxPreference;
import android.preference.Preference;
import android.preference.Preference.OnPreferenceChangeListener;
import android.preference.Preference.OnPreferenceClickListener;
import android.preference.PreferenceActivity;
import android.util.Log;

import com.zzj.ui.R;

public class PreferenceActivityTest extends PreferenceActivity {

@SuppressWarnings("deprecation")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

// 该方法已过时
addPreferencesFromResource(R.xml.preference_activity);

// 该方法已过时
CheckBoxPreference checkBoxPreference = (CheckBoxPreference) findPreference("flyMode");
/*
* 事件监听
*
* Change事件会在Click事件之前触发
*/
checkBoxPreference
.setOnPreferenceClickListener(new OnPreferenceClickListener() {

@Override
public boolean onPreferenceClick(Preference preference) {
Log.d("ClickListener_checked", String
.valueOf(((CheckBoxPreference) preference)
.isChecked()));
return false;// 事件是否结束
}
});
checkBoxPreference
.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {

@Override
public boolean onPreferenceChange(Preference preference,
Object newValue) {
Log.d("ChangeListener_checked", newValue.toString());
// 该方法是在状态更改前调用，如果返回false，状态不会更新。
return true;
}
});
}
}

PreferenceActivity布局文件：res/xml/preference_activity.xml，

<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android" >

<PreferenceCategory android:title="无线和网络" >
<CheckBoxPreference
android:key="flyMode"
android:summary="禁用所有无线连接"
android:title="飞行模式" />
<CheckBoxPreference
android:disableDependentsState="false"
android:key="wlan"
android:summary="打开WLAN"
android:title="WLAN" />
<CheckBoxPreference
android:dependency="wlan"
android:key="staticIP"
android:summary="静态IP"
android:title="静态IP" />

<ListPreference
android:defaultValue="sleepWhenScreenOff"
android:dependency="wlan"
android:dialogTitle="WLAN休眠政策"
android:entries="@array/wlan_sleep_text"
android:entryValues="@array/wlan_sleep_value"
android:key="wlanSleep"
android:negativeButtonText="取消"
android:summary="指定合适从WLAN切换至移动数据"
android:title="WLAN休眠政策" />

<CheckBoxPreference
android:key="bluetooth"
android:summary="打开蓝牙"
android:title="蓝牙" />
</PreferenceCategory>
<PreferenceCategory android:title="可编辑选项" >
<EditTextPreference
android:dialogIcon="@drawable/ic_launcher"
android:dialogMessage="dialogMessage"
android:dialogTitle="dialogTitle"
android:key="editText1"
android:negativeButtonText="取消"
android:positiveButtonText="确定"
android:summary="editText1editText1"
android:title="editText1" />
</PreferenceCategory>
<PreferenceCategory android:title="声音设置" >
<SwitchPreference
android:key="keyDownVoice"
android:title="按键声" />

<RingtonePreference
android:key="ringtone"
android:ringtoneType="ringtone"
android:title="铃声" />
<RingtonePreference
android:key="alarm"
android:ringtoneType="alarm"
android:title="闹铃" />
<RingtonePreference
android:key="notification"
android:ringtoneType="notification"
android:title="通知" />
<RingtonePreference
android:key="all"
android:ringtoneType="all"
android:title="所有" />
</PreferenceCategory>

</PreferenceScreen>

preference提供的基本组件有：CheckBoxPreference、EditTextPreference、ListPreference、RingtonePreference以及SwitchPreference。也可以定义自己的preference。

ExpandableListActivityTest.java：

package com.zzj.ui.activitydemo;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.app.ExpandableListActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ExpandableListView;
import android.widget.SimpleExpandableListAdapter;
import android.widget.Toast;

import com.zzj.ui.R;

public class ExpandableListActivityTest extends ExpandableListActivity {
private String[] names = { "腾讯", "百度", "阿里巴巴" };

private String[][] childnames = { { "QQ", "微信", "手机卫士" },
{ "百度地图", "百度视频", "PPS&奇艺" }, { "支付宝", "新浪微博", "高德地图" } };

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

List<Map<String, String>> groupData = new ArrayList<Map<String, String>>();
List<List<Map<String, String>>> childData = new ArrayList<List<Map<String, String>>>();

for (int i = 0; i < names.length; i++) {
Map<String, String> map = new HashMap<String, String>();
map.put("name", names[i]);
groupData.add(map);

String[] childs = childnames[i];
List<Map<String, String>> list = new ArrayList<Map<String, String>>();
for (int j = 0; j < childs.length; j++) {
Map<String, String> childMap = new HashMap<String, String>();
childMap.put("childname", childs[j]);
list.add(childMap);
}
childData.add(list);
}

SimpleExpandableListAdapter adapter = new SimpleExpandableListAdapter(
this, groupData, R.layout.expandable_group,
new String[] { "name" },
new int[] { R.id.expandable_group_textview }, childData,
R.layout.expandable_child, new String[] { "childname" },
new int[] { R.id.expandable_child_textview });

setListAdapter(adapter);
}

@Override
public boolean onChildClick(ExpandableListView parent, View v,
int groupPosition, int childPosition, long id) {
String text = names[groupPosition] + "\r\n"
+ childnames[groupPosition][childPosition];
Toast.makeText(this, text, Toast.LENGTH_LONG).show();
return true;
}
}

ExpandableListActivity也不需要布局文件，但是可以定义父列表布局文件和子列表布局文件。

expandable_group.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" >

<TextView
android:id="@+id/expandable_group_textview"
android:layout_marginLeft="30dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>

</LinearLayout>

expandable_child.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" >

<TextView
android:id="@+id/expandable_child_textview"
android:layout_marginLeft="50dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

</LinearLayout>

效果图：



点击参数设置：



剩余部分：



点击选择产品：