这真让我抓狂。即使有推荐的做法，我也不知道如何从配置活动中更新应用小部件。为什么在创建应用程序小部件时不调用更新方法超出了我的理解。
我想要的：一个包含项目集合（带有列表视图）的应用程序小部件。但是用户需要选择一些东西，所以我需要一个配置活动。
配置活动是ListActivity：
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
public class ChecksWidgetConfigureActivity extends SherlockListActivity {
private List<Long> mRowIDs;
int mAppWidgetId = AppWidgetManager.INVALID_APPWIDGET_ID;
private BaseAdapter mAdapter;
@Override
protected void onCreate(final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setResult(RESULT_CANCELED);
setContentView(R.layout.checks_widget_configure);
final Intent intent = getIntent();
final Bundle extras = intent.getExtras();
if (extras != null) {
mAppWidgetId = extras.getInt(AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID);
}
// If they gave us an intent without the widget id, just bail.
if (mAppWidgetId == AppWidgetManager.INVALID_APPWIDGET_ID) {
finish();
}
mRowIDs = new ArrayList<Long>(); // it's actually loaded from an ASyncTask, don't worry about that — it works.
mAdapter = new MyListAdapter((LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE));
getListView().setAdapter(mAdapter);
}
private class MyListAdapter extends BaseAdapter {
// not relevant...
}
@Override
protected void onListItemClick(final ListView l, final View v, final int position, final long id) {
if (position < mRowIDs.size()) {
// Set widget result
final Intent resultValue = new Intent();
resultValue.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, mAppWidgetId);
resultValue.putExtra("rowId", mRowIDs.get(position));
setResult(RESULT_OK, resultValue);
// Request widget update
final AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(this);
ChecksWidgetProvider.updateAppWidget(this, appWidgetManager, mAppWidgetId, mRowIDs);
}
finish();
}
}
如您所见，我正在从我的应用小部件提供程序调用静态方法。我从官方文档中得到了这个想法。
让我们看看我的提供者：
@TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH)
public class ChecksWidgetProvider extends AppWidgetProvider {
public static final String TOAST_ACTION = "com.example.android.stackwidget.TOAST_ACTION";
public static final String EXTRA_ITEM = "com.example.android.stackwidget.EXTRA_ITEM";
@Override
public void onUpdate(final Context context, final AppWidgetManager appWidgetManager, final int[] appWidgetIds) {
super.onUpdate(context, appWidgetManager, appWidgetIds);
final int N = appWidgetIds.length;
// Perform this loop procedure for each App Widget that belongs to this provider
for (int i = 0; i < N; i++) {
// Here we setup the intent which points to the StackViewService which will
// provide the views for this collection.
final Intent intent = new Intent(context, ChecksWidgetService.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.
intent.setData(Uri.parse(intent.toUri(Intent.URI_INTENT_SCHEME)));
final RemoteViews rv = new RemoteViews(context.getPackageName(), R.layout.checks_widget);
rv.setRemoteAdapter(android.R.id.list, intent);
// The empty view is displayed when the collection has no items. It should be a sibling
// of the collection view.
rv.setEmptyView(android.R.id.list, android.R.id.empty);
// 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.
final Intent toastIntent = new Intent(context, ChecksWidgetProvider.class);
toastIntent.setAction(ChecksWidgetProvider.TOAST_ACTION);
toastIntent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetIds[i]);
toastIntent.setData(Uri.parse(toastIntent.toUri(Intent.URI_INTENT_SCHEME)));
final PendingIntent toastPendingIntent = PendingIntent.getBroadcast(context, 0, toastIntent, PendingIntent.FLAG_UPDATE_CURRENT);
rv.setPendingIntentTemplate(android.R.id.list, toastPendingIntent);
appWidgetManager.updateAppWidget(appWidgetIds[i], rv);
}
}
@Override
public void onReceive(final Context context, final Intent intent) {
final AppWidgetManager mgr = AppWidgetManager.getInstance(context);
if (intent.getAction().equals(TOAST_ACTION)) {
final int appWidgetId = intent.getIntExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID);
final long rowId = intent.getLongExtra("rowId", 0);
final int viewIndex = intent.getIntExtra(EXTRA_ITEM, 0);
Toast.makeText(context, "Touched view " + viewIndex + " (rowId: " + rowId + ")", Toast.LENGTH_SHORT).show();
}
super.onReceive(context, intent);
}
@Override
public void onAppWidgetOptionsChanged(final Context context, final AppWidgetManager appWidgetManager, final int appWidgetId, final Bundle newOptions) {
updateAppWidget(context, appWidgetManager, appWidgetId, newOptions.getLong("rowId"));
}
public static void updateAppWidget(final Context context, final AppWidgetManager appWidgetManager, final int appWidgetId, final long rowId) {
final RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.checks_widget);
appWidgetManager.updateAppWidget(appWidgetId, views);
}
}
这基本上是官方文档的复制/粘贴。我们可以在这里看到我的静态方法。让我们假设它现在实际上使用了rowId。
当我收到选项更改广播 () 时，我们还可以看到另一个失败的（见下文）尝试更新应用程序小部件onAppWidgetOptionsChanged。
Service基于集合的应用小部件所需的几乎是文档的精确复制/粘贴：
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
public class ChecksWidgetService extends RemoteViewsService {
@Override
public RemoteViewsFactory onGetViewFactory(final Intent intent) {
return new StackRemoteViewsFactory(this.getApplicationContext(), intent);
}
}
class StackRemoteViewsFactory implements RemoteViewsService.RemoteViewsFactory {
private static final int mCount = 10;
private final List<WidgetItem> mWidgetItems = new ArrayList<WidgetItem>();
private final Context mContext;
private final int mAppWidgetId;
private final long mRowId;
public StackRemoteViewsFactory(final Context context, final Intent intent) {
mContext = context;
mAppWidgetId = intent.getIntExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID);
mRowId = intent.getLongExtra("rowId", 0);
}
@Override
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.
for (int i = 0; i < mCount; i++) {
mWidgetItems.add(new WidgetItem(i + " (rowId: " + mRowId + ") !"));
}
// 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.
try {
Thread.sleep(3000);
} catch (final InterruptedException e) {
e.printStackTrace();
}
}
@Override
public void onDestroy() {
// In onDestroy() you should tear down anything that was setup for your data source,
// eg. cursors, connections, etc.
mWidgetItems.clear();
}
@Override
public int getCount() {
return mCount;
}
@Override
public RemoteViews getViewAt(final 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.
final RemoteViews rv = new RemoteViews(mContext.getPackageName(), R.layout.widget_item);
rv.setTextViewText(R.id.widget_item, mWidgetItems.get(position).text);
// 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.
final Bundle extras = new Bundle();
extras.putInt(ChecksWidgetProvider.EXTRA_ITEM, position);
final 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.
try {
L.d("Loading view " + position);
Thread.sleep(500);
} catch (final InterruptedException e) {
e.printStackTrace();
}
// Return the remote views object.
return rv;
}
@Override
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;
}
@Override
public int getViewTypeCount() {
return 1;
}
@Override
public long getItemId(final int position) {
return position;
}
@Override
public boolean hasStableIds() {
return true;
}
@Override
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.
}
}
最后，我的小部件布局：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/widgetLayout"
android:orientation="vertical"
android:padding="@dimen/widget_margin"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/resizeable_widget_title"
style="@style/show_subTitle"
android:padding="2dp"
android:paddingLeft="5dp"
android:textColor="#FFFFFFFF"
android:background="@drawable/background_pink_striked_transparent"
android:text="@string/show_title_key_dates" />
<ListView
android:id="@android:id/list"
android:layout_marginRight="5dp"
android:layout_marginLeft="5dp"
android:background="@color/timeline_month_dark"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<TextView
android:id="@android:id/empty"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:textColor="#ffffff"
android:textStyle="bold"
android:text="@string/empty_view_text"
android:textSize="20sp" />
</LinearLayout>
我的 android manifest XML 文件的相关部分：
<receiver android:name="com.my.full.pkg.ChecksWidgetProvider">
<intent-filter>
<action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
</intent-filter>
<meta-data
android:name="android.appwidget.provider"
android:resource="@xml/checks_widget_info" />
</receiver>
<activity android:name="com.my.full.pkg.ChecksWidgetConfigureActivity">
<intent-filter>
<action android:name="android.appwidget.action.APPWIDGET_CONFIGURE" />
</intent-filter>
</activity>
<service
android:name="com.my.full.pkg.ChecksWidgetService"
android:permission="android.permission.BIND_REMOTEVIEWS" />
xml/checks_widget_info.xml：
<?xml version="1.0" encoding="utf-8"?>
<appwidget-provider
xmlns:android="http://schemas.android.com/apk/res/android"
android:minWidth="146dp"
android:minHeight="146dp"
android:updatePeriodMillis="86400000"
android:initialLayout="@layout/checks_widget"
android:configure="com.my.full.pkg.ChecksWidgetConfigureActivity"
android:resizeMode="horizontal|vertical"
android:previewImage="@drawable/resizeable_widget_preview" />
那么，怎么了？好吧，当我创建小部件时，它是空的。我的意思是空虚。空的。没有什么。我的布局中没有定义空视图！我勒个去？
如果我重新安装应用程序或重新启动设备（或终止启动器应用程序），应用程序小部件实际上已更新并包含自动添加的 10 个项目，如示例中所示。
配置活动完成后，我无法更新该死的东西。从文档中摘录的这句话超出了我的理解：“创建 App Widget 时不会调用 onUpdate() 方法 [...] — 它只是第一次被跳过。 ”。
我的问题是：
为什么 Android 开发团队在第一次创建小部件时选择不调用 update 呢？- 如何在配置活动完成之前更新我的应用小部件？
我不明白的另一件事是动作流程：
- 使用最后编译的代码安装应用程序，在启动器上准备空间，从启动器打开“小部件”菜单
- 选择我的小部件并将其放置到所需区域
- 在那一刻，我的应用小部件提供商收到
android.appwidget.action.APPWIDGET_ENABLED然后android.appwidget.action.APPWIDGET_UPDATE - 然后我的应用小部件提供程序
onUpdate调用它的方法。我预计这会在配置活动完成后发生...... - 我的配置活动开始了。但是应用程序小部件似乎已经创建和更新，我不明白。
- 我从我的配置活动中选择项目：
onListItemClick被调用 - 我的提供者的静态
updateAppWidget被调用，拼命地试图更新小部件。 - 配置活动设置其结果并完成。
- 提供者接收
android.appwidget.action.APPWIDGET_UPDATE_OPTIONS：嗯，在创建时接收大小更新确实很有意义。那是我拼命呼唤的地方updateAppWidget onUpdate从我的提供者没有被调用。为什么？？！！
最后：小部件是空的。不是 listview-empty 或 @android:id/empty-empty，真的是EMPTY。没有显示视图。没有什么。
如果我再次安装该应用程序，应用程序小部件将按预期填充列表视图内的视图。
调整小部件的大小没有效果。它只是再次调用onAppWidgetOptionsChanged，没有任何效果。
我的意思是空的：应用程序小部件布局已膨胀，但列表视图未膨胀，并且空视图未显示。