1.准备appwidget的初始布局和预览视图等资源
AppWidget集合应用时，需配置两种布局文件：一个用于集合view布局显示，一个用于集合view上条目的的布局显示
注意：要设置empty views，以便匹配集合view的空状态，且该View必须是集合View(一般可为ListView、GridView、StackView或AdapterViewFlipper)的同级View
2.在res/xml中创建AppWidgetProviderInfo文件
根标签为appwiget-provider，其属性要包括initialLayout、previewImage、autoAdvanceViewId 等，具体可参考后面的例子
3.创建AppWidgetProvider的实现子类，并在清单文件里面注册引用的元数据和监听的广播action
清单文件中，需给该子类配置如下信息：
action android:name="android.appwidget.action.APPWIDGET_UPDATE"
元数据：android:name="android.appwidget.provider"
代码中，onUpdate方法中完成Widget布局到桌面上时的刷新；onReceive方法中完成接收到特定广播后的Widget刷新
（另外，如果配置了Configure Activity还需要注册action,"android.appwidget.action.APPWIDGET_CONFIGURE"）
4.因为是集合Widget，需要创建一个继承了RemoteViewsService的Service子类，并在清单文件中注册权限，阻止其它程序自由访问Widget中的数据
android:permission="android.permission.BIND_REMOTEVIEWS"
代码中通过onGetViewFactory方法返回一个RemoteViewsFactory的实现类，该实现类中的onCreate()用来创建及初始化设置Widget的单个item；getViewAt()方法用来同步数据，进行耗时的更新操作，并返回RemoteView对象。
getViewAt方法中可完成：
<1>将显示独立Widget条目的view item数据以fill-in intent方式填充到集合Widget的View集合中
View集合中Chilid view不允许使用setOnClickPendingIntent的点击事件动态更新,只能通过setOnClickFillInIntent来实现，
即先设置好集合view的pending intent template点击事件模版，然后，将独立的chilid view条目的the fill-in Intent意图事件填充进来。
<2>进行耗时的处理图片和获取网络数据操作，并同步刷新Widget的显示内容。
RemoteViewsFactory的实现类中还有一个onDataSetChanged方法，也可进行耗时的处理图片和获取网络数据操作，但他可以保持Widget的当前状态，直到我们显示调用AppWidgetManager notifyAppWidgetViewDataChanged才会触发
参考：ExampleStackViewAppWidgets
本例主要参考http://developer.android.com/resources/samples/StackWidget/index.html
在其基础上略有改进
appwidget_providerinfo.xml
<?xml version="1.0" encoding="utf-8"?>
<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"
android:autoAdvanceViewId="@id/statck_view"
android:initialLayout="@layout/widget_layout"
android:minHeight="74dp"
android:minWidth="290dp"
android:previewImage="@drawable/doraemon"
android:updatePeriodMillis="3600000"
android:resizeMode="vertical">
</appwidget-provider>
StackViewAppWidgetService.java
/**
* 实现了给StackView上ImageView适配背景图片
* @author wgyang
*
*/
public class StackViewAppWidgetService extends RemoteViewsService {
@Override
public RemoteViewsFactory onGetViewFactory(Intent intent) {
return new ViewFlipperRemoteViewsFactory(this.getApplicationContext(),
intent);
}
}
class ViewFlipperRemoteViewsFactory implements
RemoteViewsService.RemoteViewsFactory {
int[] images = { R.drawable.doraemon, R.drawable.baidu, R.drawable.bing,
R.drawable.google };
//int[] colors = { Color.BLUE, Color.RED, Color.GRAY, Color.GREEN };
private static final int mCount = 4;
private List<ImageView> mImageViews = new ArrayList<ImageView>();
private Context mContext;
private static ImageView mImageView;
public ViewFlipperRemoteViewsFactory(Context context, Intent intent) {
mContext = context;
}
public void onCreate() {
// In onCreate() you setup any connections / cursors to your data source. Heavy lifting,
// for example downloading or creating content etc, should be deferred to onDataSetChanged()
// or getViewAt(). Taking more than 20 seconds in this call will result in an ANR.
// 因不是很耗时，可放在这里
//在循环里控制显示独立Widget条目的界面信息
for (int i = 0; i < mCount; ++i) {
mImageView = new ImageView(mContext);
//mImageView.setBackgroundColor(colors[i]);
//mImageView.setImageResource(images[i]);
mImageViews.add(mImageView);
}
// We sleep for 3 seconds here to show how the empty view appears in the interim.
// The empty view is set in the StackWidgetProvider and should be a sibling of the
// collection view.
}
public RemoteViews getViewAt(int position) {
// position will always range from 0 to getCount() - 1.
// We construct a remote views item based on our widget item xml file, and set the
// text based on the position.
//通过Remoteview给view item上设置要显示内容
RemoteViews rv = new RemoteViews(mContext.getPackageName(),
R.layout.widget_item);
// rv.setTextViewText(R.id.widget_item,
// mWidgetItems.get(position).text);
//rv.setImageViewResource(R.id.widget_item, mImageViews.get(position)
// .getBackground().getLevel());
//注意要将单个的widget条目信息设置进rv中，不然刷新界面不成功的
rv.setImageViewBitmap(R.id.widget_item, BitmapFactory.decodeResource(
mContext.getResources(), images[position]));
// Next, we set a fill-intent which will be used to fill-in the pending intent template
// which is set on the collection view in StackWidgetProvider.
//item的位置信息设置到fillintent中
Bundle extras = new Bundle();
extras.putInt(StackViewAppWidgetProvider.EXTRA_ITEM, position);
//设置fill-intent以填充Pending intent 模版
Intent fillInIntent = new Intent();
fillInIntent.putExtras(extras);
rv.setOnClickFillInIntent(R.id.widget_item, fillInIntent);
// You can do heaving lifting in here, synchronously. For example, if you need to
// process an image, fetch something from the network, etc., it is ok to do it here,
// synchronously. A loading view will show up in lieu of the actual contents in the
// interim.
//其它耗时操作可在这里完成
return rv;
}
public int getCount() {
return mCount;
}
public RemoteViews getLoadingView() {
// You can create a custom loading view (for instance when getViewAt() is slow.) If you
// return null here, you will get the default loading view.
return null;
}
public int getViewTypeCount() {
return 1;//注意下，初始是0，改变与否不影响
}
public long getItemId(int position) {
return position;
}
public boolean hasStableIds() {
return true;//注意下，原来是false，改变与否不影响
}
public void onDataSetChanged() {
// This is triggered when you call AppWidgetManager notifyAppWidgetViewDataChanged
// on the collection view corresponding to this factory. You can do heaving lifting in
// here, synchronously. For example, if you need to process an image, fetch something
// from the network, etc., it is ok to do it here, synchronously. The widget will remain
// in its current state while work is being done here, so you don't need to worry about
// locking up the widget.
//耗时操作可放在这里，可显式触发
}
public void onDestroy() {
// In onDestroy() you should tear down anything that was setup for your data source,
// eg. cursors, connections, etc.
mImageViews.clear();
}
}
StackViewAppWidgetProvider.java
/**
* StackView更新图片
* 定时接收广播，自动刷新view，另外监听点击事件，弹土司消息反馈点击的是哪一个条目
* @author wgyang
*
*/
public class StackViewAppWidgetProvider extends AppWidgetProvider {
public static final String TOAST_ACTION = "com.lenove.widgetcollection.TOAST_ACTION";
public static final String EXTRA_ITEM = "com.lenove.widgetcollection.EXTRA_ITEM";
@Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals(TOAST_ACTION)) {
int viewIndex = intent.getIntExtra(EXTRA_ITEM, 0);
Toast.makeText(context, "Touched view " + viewIndex, Toast.LENGTH_SHORT).show();
}
super.onReceive(context, intent);
}
// 完成Widget布局到桌面上时的刷新
@Override
public void onUpdate(Context context, AppWidgetManager appWidgetManager,int[] appWidgetIds) {
// update each of the widgets with the remote adapter
//遍历每个appWidgetId
for (int i = 0; i < appWidgetIds.length; ++i) {
// Here we setup the intent which points to the StackViewService which will
// provide the views for this collection.
//指定启动到RemoteViewstService的Intent
Intent intent = new Intent(context, StackViewAppWidgetService.class);
intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetIds[i]);
// When intents are compared, the extras are ignored, so we need to embed the extras
// into the data so that the extras will not be ignored.
// 嵌入数据到intent，以避免intent中的数据被忽略掉
intent.setData(Uri.parse(intent.toUri(Intent.URI_INTENT_SCHEME)));
//借助RemoteView传递信息
RemoteViews rv = new RemoteViews(context.getPackageName(), R.layout.widget_layout);
//注意，设置适配器
rv.setRemoteAdapter(appWidgetIds[i], R.id.statck_view, intent);
// The empty view is displayed when the collection has no items. It should be a sibling
// of the collection view.
//注意，设置空状态
rv.setEmptyView(R.id.statck_view, R.id.empty_view);
// Here we setup the a pending intent template. Individuals items of a collection
// cannot setup their own pending intents, instead, the collection as a whole can
// setup a pending intent template, and the individual items can set a fillInIntent
// to create unique before on an item to item basis.
//设置封装了操作信息的intnent--最终放到pendingIntentTemplate中
Intent toastIntent = new Intent(context, StackViewAppWidgetProvider.class);
toastIntent.setAction(StackViewAppWidgetProvider.TOAST_ACTION);
toastIntent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetIds[i]);
intent.setData(Uri.parse(intent.toUri(Intent.URI_INTENT_SCHEME)));
//设置延迟意图模版PendingIntentTemplete，加载到RemoteViews，最后由AppWidgetManager更新
PendingIntent toastPendingIntent = PendingIntent.getBroadcast(context, 0, toastIntent,
PendingIntent.FLAG_UPDATE_CURRENT);
rv.setPendingIntentTemplate(R.id.statck_view, toastPendingIntent);
//如果有耗时的操作应该启动应该服务Service去完成
appWidgetManager.updateAppWidget(appWidgetIds[i], rv);
}
super.onUpdate(context, appWidgetManager, appWidgetIds);
}
}
摘自：http://wenku.baidu.com/view/aab74fa4b0717fd5360cdc4a.html