Android编程之桌面小部件AppWidgetProvider用法示例

本文实例讲述了android编程之桌面小部件appwidgetprovider用法。分享给大家供大家参考，具体如下：

/**
 * 桌面小部件 appwidget配置
 *
 * @description：
 * @author ldm
 * @date 2016-5-16 下午1:57:16
 */
public class exampleappwidgetconfigure extends activity {
  static final string tag = "exampleappwidgetconfigure";
  // 保存的文件名
  private static final string prefs_name = "com.example.android.apis.appwidget.exampleappwidgetprovider";
  // 保存的字段key
  private static final string pref_prefix_key = "prefix_";
  // 小部件 对应id
  int mappwidgetid = appwidgetmanager.invalid_appwidget_id;
  // 输入框
  edittext mappwidgetprefix;
  public exampleappwidgetconfigure() {
    super();
  }
  @override
  public void oncreate(bundle icicle) {
    super.oncreate(icicle);
    setresult(result_canceled);
    // 设置布局
    setcontentview(r.layout.appwidget_configure);
    mappwidgetprefix = (edittext) findviewbyid(r.id.appwidget_prefix);
    // 设置监听
    findviewbyid(r.id.save_button).setonclicklistener(monclicklistener);
    // 获取intent传递过来的数据
    intent intent = getintent();
    bundle extras = intent.getextras();
    if (extras != null) {
      mappwidgetid = extras.getint(appwidgetmanager.extra_appwidget_id,
          appwidgetmanager.invalid_appwidget_id);
    }
    if (mappwidgetid == appwidgetmanager.invalid_appwidget_id) {
      finish();
    }
    mappwidgetprefix.settext(loadtitlepref(exampleappwidgetconfigure.this,
        mappwidgetid));
  }
  view.onclicklistener monclicklistener = new view.onclicklistener() {
    public void onclick(view v) {
      final context context = exampleappwidgetconfigure.this;
      string titleprefix = mappwidgetprefix.gettext().tostring();
      //保存到sharedpreferences文件
      savetitlepref(context, mappwidgetid, titleprefix);
      appwidgetmanager appwidgetmanager = appwidgetmanager
          .getinstance(context);
      //更新小部件
      exampleappwidgetprovider.updateappwidget(context, appwidgetmanager,
          mappwidgetid, titleprefix);
      intent resultvalue = new intent();
      resultvalue.putextra(appwidgetmanager.extra_appwidget_id,
          mappwidgetid);
      setresult(result_ok, resultvalue);
      finish();
    }
  };
  static void savetitlepref(context context, int appwidgetid, string text) {
    sharedpreferences.editor prefs = context.getsharedpreferences(
        prefs_name, 0).edit();
    prefs.putstring(pref_prefix_key + appwidgetid, text);
    prefs.commit();
  }
  static string loadtitlepref(context context, int appwidgetid) {
    sharedpreferences prefs = context.getsharedpreferences(prefs_name, 0);
    string prefix = prefs.getstring(pref_prefix_key + appwidgetid, null);
    if (prefix != null) {
      return prefix;
    } else {
      return context.getstring(r.string.appwidget_prefix_default);
    }
  }
  static void deletetitlepref(context context, int appwidgetid) {
  }
  static void loadalltitleprefs(context context,
      arraylist<integer> appwidgetids, arraylist<string> texts) {
  }
}

<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:orientation="vertical" >
  <textview
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="this text will be shown before the date in our example widget." />
  <edittext
    android:id="@+id/appwidget_prefix"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />
  <button
    android:id="@+id/save_button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@android:string/ok" />
</linearlayout>

/**
 * appwidgetprovider小部件广播组件使用：
 * 1， 实现appwidgetprovider的子类，并至少override onupdate()方法
 * 2，在androidmanifest.xml中，声明上述的appwidgetprovider的子类是一个receiver，并且：
 * 该receiver的intent-filter的action必须包含“android.appwidget.action.appwidget_update”；
 * 该receiver的meta-data为“android.appwidget.provider”，并用一个xml文件来描述布局属性。
 * 3， 在第2点中的xml文件中描述布局属性的节点名称必须为“appwidget-provider”。
 *
 * @description：
 * @author ldm
 * @date 2016-5-16 下午1:43:31
 */
public class exampleappwidgetprovider extends appwidgetprovider {
  // log打印日志标签
  private static final string tag = "exampleappwidgetprovider";
  /**
   * onupdate() 处理appwidgetmanager.action_appwidget_update广播。
   * 该广播在需要appwidgetprovider提供remoteviews数据时
   * ，由appwidgetservice.sendupdateintentlocked()发出。
   */
  @override
  public void onupdate(context context, appwidgetmanager appwidgetmanager,
      int[] appwidgetids) {
    log.d(tag, "onupdate");
    final int n = appwidgetids.length;
    for (int i = 0; i < n; i++) {
      //获取到id
      int appwidgetid = appwidgetids[i];
      //设置标题
      string titleprefix = exampleappwidgetconfigure.loadtitlepref(
          context, appwidgetid);
      //更新appwidget
      updateappwidget(context, appwidgetmanager, appwidgetid, titleprefix);
    }
  }
  /**
   * ondeleted() 处理appwidgetmanager.action_appwidget_deleted广播。
   * 该广播在有该appwidgetprovider的实例被删除时
   * ，由appwidgetservice.deleteappwidgetlocked()发出。
   */
  @override
  public void ondeleted(context context, int[] appwidgetids) {
    log.d(tag, "ondeleted");
    final int n = appwidgetids.length;
    for (int i = 0; i < n; i++) {
      exampleappwidgetconfigure.deletetitlepref(context, appwidgetids[i]);
    }
  }
  /**
   * onenabled() 处理appwidgetmanager.action_appwidget_enabled广播。
   * 该广播在该appwidgetprovider被实例化时，由appwidgetservice.sendenableintentlocked()发出。
   */
  @override
  public void onenabled(context context) {
    log.d(tag, "onenabled");
    packagemanager pm = context.getpackagemanager();
    pm.setcomponentenabledsetting(new componentname(
        "com.example.android.apis",
        ".appwidget.examplebroadcastreceiver"),
        packagemanager.component_enabled_state_enabled,
        packagemanager.dont_kill_app);
  }
  /**
   * ondisabled() 处理appwidgetmanager.action_appwidget_disabled广播。
   * 该广播在该appwidgetprovider的所有实例中的最后一个实例被删除时
   * ，由appwidgetservice.deleteappwidgetlocked()发出。
   */
  @override
  public void ondisabled(context context) {
    log.d(tag, "ondisabled");
    packagemanager pm = context.getpackagemanager();
    //设置组件可用
    pm.setcomponentenabledsetting(new componentname(
        "com.example.android.apis",
        ".appwidget.examplebroadcastreceiver"),
        packagemanager.component_enabled_state_enabled,
        packagemanager.dont_kill_app);
  }
  static void updateappwidget(context context,
      appwidgetmanager appwidgetmanager, int appwidgetid,
      string titleprefix) {
    log.d(tag, "updateappwidget appwidgetid=" + appwidgetid
        + " titleprefix=" + titleprefix);
    charsequence text = context.getstring(r.string.appwidget_text_format,
        exampleappwidgetconfigure.loadtitlepref(context, appwidgetid),
        "0x" + long.tohexstring(systemclock.elapsedrealtime()));
    // 创建remoteviews 对象
    remoteviews views = new remoteviews(context.getpackagename(),
        r.layout.appwidget_provider);
    // 设置remoteviews 对象的文本
    views.settextviewtext(r.id.appwidget_text, text);
    // 告诉appwidgetmanager 显示 views对象给widget.
    appwidgetmanager.updateappwidget(appwidgetid, views);
  }
}

小部件布局

<?xml version="1.0" encoding="utf-8"?>
<textview xmlns:android="http://schemas.android.com/apk/res/android"
  android:id="@+id/appwidget_text"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:background="#ffff00ff"
  android:textcolor="#ff000000"
/>

public class examplebroadcastreceiver extends broadcastreceiver {
  @override
  public void onreceive(context context, intent intent) {
    log.d("exmamplebroadcastreceiver", "intent=" + intent);
    //获取广播的action
    string action = intent.getaction();
    //对action进行判断
    if (action.equals(intent.action_timezone_changed)
        || action.equals(intent.action_time_changed)) {
      appwidgetmanager gm = appwidgetmanager.getinstance(context);
      arraylist<integer> appwidgetids = new arraylist<integer>();
      arraylist<string> texts = new arraylist<string>();
      exampleappwidgetconfigure.loadalltitleprefs(context, appwidgetids, texts);
      final int n = appwidgetids.size();
      for (int i=0; i<n; i++) {
        exampleappwidgetprovider.updateappwidget(context, gm, appwidgetids.get(i), texts.get(i));
      }
    }
  }
}

在androidmanifest.xml中添加相应组件：

exampleappwidgetconfigure

<activity android:name=".appwidget.exampleappwidgetconfigure" >
  <intent-filter>
    <action android:name="android.appwidget.action.appwidget_configure" />
  </intent-filter>
</activity>

exampleappwidgetprovider

<receiver android:name=".appwidget.exampleappwidgetprovider" >
  <meta-data
    android:name="android.appwidget.provider"
    android:resource="@xml/appwidget_provider" />
  <intent-filter>
    <action android:name="android.appwidget.action.appwidget_update" />
  </intent-filter>
</receiver>

examplebroadcastreceiver

 <receiver
  android:name=".appwidget.examplebroadcastreceiver"
  android:enabled="false" >
  <intent-filter>
    <action android:name="android.intent.action_timezone_changed" />
    <action android:name="android.intent.action_time" />
  </intent-filter>
</receiver>

开源代码：https://github.com/ldm520/android_api_demos

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