我正在开发 Android Widget，我的小部件如下图所示， [上一篇] 活动名称 [下一篇]
prev，next 是小部件上的按钮。所以我想在单击 next 和 prev 按钮时更新事件名称。在服务启动时，我加载数据并将其存储在数组列表中。现在我想通过单击小部件上的下一个和上一个按钮来遍历数组列表。
那么我怎样才能做到这一点。请帮我找到合适的解决方案。 这是我的 xml 布局
<LinearLayout
android:id="@+id/lytWidget2"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginTop="5dip"
android:orientation="horizontal" >
<Button
android:id="@+id/btnPreviousView"
android:layout_width="43dp"
android:layout_height="fill_parent"
android:layout_gravity="left|center"
android:background="@drawable/ic_leftarrow"
android:padding="5dip" />
<TextView
android:layout_width="wrap_content"
android:layout_height="52dp"
android:layout_weight="0.97"
android:text="Event Name" />
<Button
android:id="@+id/btnNextView"
android:layout_width="43dp"
android:layout_height="fill_parent"
android:layout_gravity="right|center_vertical"
android:background="@drawable/ic_rightarrow"
android:padding="5dip" />
</LinearLayout>
所以，只需像这样处理
AppWidgetProvider示例代码
@Override
public void onReceive(Context context, Intent intent)
{
super.onReceive(context, intent);
RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.widget);
// find your TextView here by id here and update it.
Toast.makeText(context, "Clicked!!", Toast.LENGTH_SHORT).show();
}
首先，在您的
WidgetProviderClassprivate static final String ACTION_UPDATE_CLICK_NEXT = "action.UPDATE_CLICK_NEXT";
private static final String ACTION_UPDATE_CLICK_PREVIOUS = "action.UPDATE_CLICK_PREVIOUS";
接下来，在您重写的
onUpdate()@Override
public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
RemoteViews views = new RemoteViews(context.getPackageName(),R.layout.your_widget_layout);
views.setOnClickPendingIntent(R.id.nextButtonWidget, getPendingSelfIntent(context, ACTION_UPDATE_CLICK_NEXT));
views.setOnClickPendingIntent(R.id.previousButtonWidget, getPendingSelfIntent(context, ACTION_UPDATE_CLICK_PREVIOUS));
}
用于创建指向当前类（自身）的意图的函数：
private PendingIntent getPendingSelfIntent(Context context, String action) {
Intent intent = new Intent(context, getClass()); // An intent directed at the current class (the "self").
intent.setAction(action);
return PendingIntent.getBroadcast(context, 0, intent, 0);
}
当事件发生
onReceive() @Override
public void onReceive(Context context, Intent intent) {
super.onReceive(context, intent);
if (ACTION_UPDATE_CLICK_NEXT.equals(intent.getAction())) {
// if the user clicked next
}
else if (ACTION_UPDATE_CLICK_PREVIOUS.equals(intent.getAction())) {
// if the user clicked previous
}
}
奖金： 如果你想调用
onUpdate()/**
* A general technique for calling the onUpdate method,
* requiring only the context parameter.
*
* @author John Bentley, based on Android-er code.
* @see <a href="http://android-er.blogspot.com
* .au/2010/10/update-widget-in-onreceive-method.html">
* Android-er > 2010-10-19 > Update Widget in onReceive() method</a>
*/
private void onUpdate(Context context) {
AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
ComponentName thisAppWidgetComponentName = new ComponentName(context.getPackageName(), getClass().getName());
int[] appWidgetIds = appWidgetManager.getAppWidgetIds(thisAppWidgetComponentName);
onUpdate(context, appWidgetManager, appWidgetIds);
}
NewAppWidget.java
package com.example.android.appwidgetsample;
import android.app.PendingIntent;
import android.appwidget.AppWidgetManager;
import android.appwidget.AppWidgetProvider;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.widget.RemoteViews;
import java.text.DateFormat;
import java.util.Date;
/**
* App widget provider class, to handle update broadcast intents and updates
* for the app widget.
*/
public class NewAppWidget extends AppWidgetProvider {
// Name of shared preferences file & key
private static final String SHARED_PREF_FILE =
"com.example.android.appwidgetsample";
private static final String COUNT_KEY = "count";
/**
* Update a single app widget. This is a helper method for the standard
* onUpdate() callback that handles one widget update at a time.
*
* @param context The application context.
* @param appWidgetManager The app widget manager.
* @param appWidgetId The current app widget id.
*/
private void updateAppWidget(Context context,
AppWidgetManager appWidgetManager,
int appWidgetId) {
// Get the count from prefs.
SharedPreferences prefs =
context.getSharedPreferences(SHARED_PREF_FILE, 0);
int count = prefs.getInt(COUNT_KEY + appWidgetId, 0);
count++;
// Get the current time.
String dateString =
DateFormat.getTimeInstance(DateFormat.SHORT).format(new Date());
// Construct the RemoteViews object.
RemoteViews views = new RemoteViews(context.getPackageName(),
R.layout.new_app_widget);
views.setTextViewText(R.id.appwidget_id,
String.valueOf(appWidgetId));
views.setTextViewText(R.id.appwidget_update,
context.getResources().getString(
R.string.date_count_format, count, dateString));
// Save count back to prefs.
SharedPreferences.Editor prefEditor = prefs.edit();
prefEditor.putInt(COUNT_KEY + appWidgetId, count);
prefEditor.apply();
// Setup update button to send an update request as a pending intent.
Intent intentUpdate = new Intent(context, NewAppWidget.class);
// The intent action must be an app widget update.
intentUpdate.setAction(AppWidgetManager.ACTION_APPWIDGET_UPDATE);
// Include the widget ID to be updated as an intent extra.
int[] idArray = new int[]{appWidgetId};
intentUpdate.putExtra(AppWidgetManager.EXTRA_APPWIDGET_IDS, idArray);
// Wrap it all in a pending intent to send a broadcast.
// Use the app widget ID as the request code (third argument) so that
// each intent is unique.
PendingIntent pendingUpdate = PendingIntent.getBroadcast(context,
appWidgetId, intentUpdate, PendingIntent.FLAG_UPDATE_CURRENT);
// Assign the pending intent to the button onClick handler
views.setOnClickPendingIntent(R.id.button_update, pendingUpdate);
// Instruct the widget manager to update the widget.
appWidgetManager.updateAppWidget(appWidgetId, views);
}
/**
* Override for onUpdate() method, to handle all widget update requests.
*
* @param context The application context.
* @param appWidgetManager The app widget manager.
* @param appWidgetIds An array of the app widget IDs.
*/
@Override
public void onUpdate(Context context, AppWidgetManager appWidgetManager,
int[] appWidgetIds) {
// There may be multiple widgets active, so update all of them.
for (int appWidgetId : appWidgetIds) {
updateAppWidget(context, appWidgetManager, appWidgetId);
}
}
}
NewAppWidget.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#09C"
android:padding="@dimen/widget_margin" >
<!-- Panel for Widget ID -->
<LinearLayout
android:id="@+id/section_id"
style="@style/AppWidgetSection"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true"
android:orientation="horizontal">
<TextView
android:id="@+id/appwidget_id_label"
style="@style/AppWidgetLabel"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="2"
android:text="@string/widget_id_label"/>
<TextView
android:id="@+id/appwidget_id"
style="@style/AppWidgetText"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="end"
android:text="XX"/>
</LinearLayout>
<!-- Panel for widget update date and number of updates -->
<LinearLayout
android:id="@+id/section_update"
style="@style/AppWidgetSection"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_below="@+id/section_id"
android:orientation="vertical">
<TextView
android:id="@+id/appwidget_update_label"
style="@style/AppWidgetLabel"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="2dp"
android:text="@string/widget_update_label"/>
<TextView
android:id="@+id/appwidget_update"
style="@style/AppWidgetText"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/date_count_format"/>
</LinearLayout>
<!-- Update widget button -->
<Button
android:id="@+id/button_update"
style="@style/AppWidgetButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/section_update"
android:layout_centerHorizontal="true"
android:text="@string/widget_button_update" />
</RelativeLayout>
private static final String ACTION_UPDATE_CLICK_NEXT = "action.UPDATE_CLICK_NEXT";
private static final String ACTION_UPDATE_CLICK_PREVIOUS = "action.UPDATE_CLICK_PREVIOUS";
AppWidgetManager#getAppWidgetIds()@Override
public void onReceive(Context context, Intent intent) {
super.onReceive(context, intent);
if (ACTION_UPDATE_CLICK_NEXT.equals(intent.getAction()) || ACTION_UPDATE_CLICK_PREVIOUS.equals(intent.getAction()) ) {
int[] appWidgetIds = intent.getIntArrayExtra(AppWidgetManager.EXTRA_APPWIDGET_IDS);
drawWidgets(context, appWidgetIds);
} else {
AppWidgetManager widgetManager = AppWidgetManager.getInstance(context);
ComponentName widgetComponent = new ComponentName(context, getClass());
int[] appWidgetIds = widgetManager.getAppWidgetIds(widgetComponent);
drawWidgets(context, appWidgetIds);
}
}
当然，你应该将 app-widget-ids 作为额外的传递给意图
private void drawWidget(Context context, int appWidgetId) {
AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
RemoteViews remoteView = new RemoteViews(context.getPackageName(), R.layout.widget_light);
...
Intent intent = new Intent(context, getClass());
intent.setAction(AppWidgetManager.ACTION_APPWIDGET_UPDATE);
int[] ids = AppWidgetManager.getInstance(context).getAppWidgetIds(new ComponentName(context, getClass()));
//put the IDs in the intent. We may not get it from AppWidgetManager
intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_IDS, ids);
int flags = (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) ? PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_IMMUTABLE : PendingIntent.FLAG_UPDATE_CURRENT;
PendingIntent pendingIntent= PendingIntent.getBroadcast(context, 0, intent, flags);
remoteView.setOnClickPendingIntent(R.id.nextButtonWidget, pendingIntent);
appWidgetManager.updateAppWidget(appWidgetId, remoteView);
}