AndroidWidget基本用法

1.为widget创建一个布局:

<?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/tv_date"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content" />

</LinearLayout>

2.创建xml文件夹,配置appwidget-provider

<?xml version="1.0" encoding="utf-8"?>

<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"

    android:minHeight="100dp"

    android:minWidth="100dp"

    android:updatePeriodMillis="50000" >

</appwidget-provider>

3.创建Widget的广播,继承自AppWidgetProvider:

onEnabled:    第一个widget添加到屏幕上执行(启动服务)

onDisabled:    最后一个widget从屏幕移除(停止服务)

onDeleted:    widget从屏幕移除

onUpdate:    刷新widget(通过RemoteViews和AppWidgetManager进行更新操作)

广播的配置:

        <receiver android:name="com.tomorrow_p.widget_p.WidgetProvider" >

            <intent-filter>

                <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />

            </intent-filter>

            <meta-data

                android:name="android.appwidget.provider"

                android:resource="@xml/widget_config" />

        </receiver>

在服务中操作widget...

        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd   hh:mm:ss");

        String date = format.format(new Date());

        RemoteViews rv = new RemoteViews(getPackageName(), R.layout.widget);

        rv.setTextViewText(R.id.tv_date, date);

        AppWidgetManager instance = AppWidgetManager

                .getInstance(getApplicationContext());

        ComponentName provider = new ComponentName(getApplicationContext(),

                WidgetProvider.class);

        instance.updateAppWidget(provider, rv);