android - 具有多个待定 Intent 的 ListView 小部件

Question

我将小部件与具有 3 种类型的项目的 ListView 一起使用。对于每种类型的项目，我应该使用不同的待定 Intent 。目前我正在使用以下代码:

public class MyWidgetProvider extends AppWidgetProvider {

    @Override
    public void onUpdate(Context context, AppWidgetManager widgetManager, int[] widgetIds) {
        for (int widgetId : widgetIds) {
            RemoteViews remoteViews = new RemoteViews(context.getPackageName(), R.layout.widget_view);
            bindEmptyView(remoteViews);
            bindRemoteAdapter(context, widgetId, remoteViews);
            bindIntentTemplate(context, widgetId, remoteViews);
            widgetManager.updateAppWidget(widgetId, remoteViews);
        }
    }

    private void bindEmptyView(RemoteViews remoteViews) {
        remoteViews.setEmptyView(android.R.id.list, android.R.id.empty);
    }

    private void bindRemoteAdapter(Context context, int widgetId, RemoteViews remoteViews) {
        Intent intent = new Intent(context, MyViewService.class);
        intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, widgetId);
        intent.setData(Uri.parse(intent.toUri(Intent.URI_INTENT_SCHEME)));
        remoteViews.setRemoteAdapter(android.R.id.list, intent);
    }

    private void bindIntentTemplate(Context context, int widgetId, RemoteViews remoteViews) {

        Intent intent = new Intent(context, MyActivity.class);
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
        intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, widgetId);
        intent.setData(Uri.parse(intent.toUri(Intent.URI_INTENT_SCHEME)));
        PendingIntent template = PendingIntent.getActivity(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
        remoteViews.setPendingIntentTemplate(android.R.id.list, template);
    }
}

从这一点来看，我不明白如何为不同的列表项调用特定的 Intent 。

Answer 1

希望我能很好地理解您的问题，所以我会尝试详细解释发生了什么以及如何处理对小部件上列表项的点击。

我假设您已经知道您必须实现一个类:

extends BroadcastReceiver implements RemoteViewsService.RemoteViewsFactory

这将作为您的小部件的 ListView(我们称它为 MyListRemoteViewFactory)的“适配器”。 如果您想处理小部件的 listView 上的项目点击，您可以执行以下操作:

1) 在你的 AppWidgetProvider 类中设置一个 setPendingIntentTemplate

2) 在 MyListRemoteViewFactory 中设置一个 setOnClickFillInIntent 覆盖 getViewAt(int position) 方法

现在: 执行第 1 步)时，您可能想执行以下操作:

final Intent serviceIntent = new Intent(context, MyListRemoteViewFactory.class);
serviceIntent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, widgetId);
serviceIntent.setData(Uri.parse(serviceIntent.toUri(Intent.URI_INTENT_SCHEME)));
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
    views.setRemoteAdapter(R.id.widget_list_view, serviceIntent);
} else {
    views.setRemoteAdapter(widgetId, R.id.widget_list_view, serviceIntent);
}

// Individuals items of a collection cannot set up their own pending intents. Instead, the collection as a whole sets up a pending intent template and the individual
// items set a fillInIntent to create unique behavior on an item-by-item basis.
Intent listItemClickIntent = new Intent(context, MyWidgetProvider.class); // This is the name of your AppWidgetProvider class
// Set the action for the intent. When the user touches a particular view, it will have the effect of broadcasting an action
listItemClickIntent.setAction(context.getString("com.example.list.item.click"));
 listItemClickIntent.setData(Uri.parse(listItemClickIntent.toUri(Intent.URI_INTENT_SCHEME)));
PendingIntent clickPendingIntent = PendingIntent.getBroadcast(context, 0, listItemClickIntent, PendingIntent.FLAG_UPDATE_CURRENT);
views.setPendingIntentTemplate(R.id.widget_list_view, clickPendingIntent);

您可以将上述代码 fragment 放在初始化 RemoteViews 对象的任何位置之后:

RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.layout_widget);)

现在您已经准备好 pendingIntentTemplate。另一件要做的事情是实现类的 onReceive 方法，这样您就可以决定在发生上述情况的操作时要做什么。所以你会做类似的事情:

@Override
public void onReceive(Context context, Intent intent) {
    // Called on every broadcast and before each of the above callback methods.
    super.onReceive(context, intent);

    ComponentName name = new ComponentName(context, WidgetProvider.class);
    int[] appWidgetIds = AppWidgetManager.getInstance(context).getAppWidgetIds(name);
    if (appWidgetIds == null || appWidgetIds.length == 0) {
        return;
    }

    AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);

    if (intent.getAction().equals("com.example.list.item.click") { 
        // This is where you have to decide what you'll do depending on which list item was tapped. BUT this depends on the fill Intent set in the MyListRemoteViewFactory class's getViewAt() method
        // I'll jump straight to the logic here, but once you're done reading this post, get back here to understand the logic because this is the key here. But simple as hell.
        int simpleDecidingFactor =  intent.getIntExtra("SELECTED_ITEM", 0)
        if (simpleDecidingFactor != 0) {
            if (simpleDecidingFactor == 1) {
                // Do something for the first case. Probably open activity2
            } else if (simpleDecidingFactor == 2) {
                // Do something for the second case. Probably open activity2
            } else if (simpleDecidingFactor == 3) {
                // Do something for the second case. Probably open activity3
            }
         }
    }
}

[该死的，这会很长]

执行第 2 步)(从现在开始我们讨论 MyListRemoteViewFactory 类中的实现)

如果您需要列表中的 3 个不同的项目，首先您必须将此方法添加到 MyListRemoteViewFactory(无论如何您都必须重写它，关键是返回您拥有的 View 数):

@Override
public int getViewTypeCount() {
    return 3;
}

在 getViewAt() 方法中，您可以添加基于什么的逻辑，您可以根据您的位置决定显示什么。像这样的东西:

@Override
public RemoteViews getViewAt(int position) {
    if (position >= mItems.size()) {
        return null;
    }

    RemoteViews views;
    if (mItems.get(position).getViewType() == 0) {
        views = new RemoteViews(mContext.getPackageName(), R.layout.list_item_first);
        setUpItem(views, mItems.get(position), 1); // !!!! the 3rd parameter is very important here, as you'll expect this number in the MyWidgetProvider class' onReceive method. See the simpleDecidingFactor variable there.
    } else if (mItems.get(position).getViewType() == 1) {
        views = new RemoteViews(mContext.getPackageName(), R.layout.list_item_second);
        setUpItem(views, mItems.get(position), 2);
    } else {
        views = new RemoteViews(mContext.getPackageName(), R.layout.list_item_third);
        setUpItem(views, mItems.get(position), 3);
    } // Or add whatever logic you have. Here, I supposed I have a field inside my object telling me what type my item is

    return views;
}

setUpItem 方法可能类似于:

private void setUpItem(RemoteViews views, MyObject object, int viewTypeKey) {
     // This is where you set your clickFillInIntent. Without setting it, nothing'll be functional

    Bundle extras = new Bundle();
    extras.putInt("SELECTED_ITEM", viewTypeKey);
    //extras.putParcelable("LIST_ITEM_OBJECT", object); // You may send your object as well if you need it
    Intent fillInIntent = new Intent();
    fillInIntent.putExtras(extras);

    // You have your fillInIntent prepared, you only have to decide on what view to place it.
    // I assume you have a Button on all 3 of your list item layouts with the id button_click. Let's place the Intent:

    views.setOnClickFillInIntent(R.id.button_click, fillInIntent);
}

您可能想确保您也在 list 文件中声明了所有内容。您必须声明您的 widgetprovider、列表的接收者以及处理您的 Factoryclass 的服务。你应该有这样的东西:

<receiver
    android:name=".MyWidgetProvider"
    android:enabled="true"
    android:label="My awesome widget">
    <intent-filter>
        <action android:name="android.appwidget.action.APPWIDGET_ENABLED" />
        <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
        <action android:name="android.appwidget.action.APPWIDGET_DELETED" />
        <action android:name="android.appwidget.action.APPWIDGET_DISABLED" />
        <!-- You have to declare your used actions here, so the AppWidgetProvider knows what to listen for-->
            <action android:name="com.example.list.item.click"/>
    </intent-filter>

    <meta-data
        android:name="android.appwidget.provider"
        android:resource="@xml/widget_provider_info"/>
</receiver>

<!-- The service serving the RemoteViews to the collection widget -->
<service
    android:name=".WidgetRemoteViewsService"
    android:exported="false"
    android:permission="android.permission.BIND_REMOTEVIEWS"/>

<receiver
    android:name=".ui.widget.MyListRemoteViewFactory"
    android:enabled="true"
    android:exported="false">
    <intent-filter>
        <category android:name="android.intent.category.DEFAULT"/>
        <!-- You might want to use an action to notify the appwidget provider from the MyListRemoteViewFactory's onReceive method. This class extends a BroadcastReceiver, so you must implement it's onReceive(Context context, Intent intent) method. If you need help on this, let me know and I'll edit my answer with some example for that too -->
        <action android:name="com.example.refresh.remote.views"/>
    </intent-filter>
</receiver>

啊，顺便说一句，WidgetRemoteViewsService 类应该如下所示:

public class WidgetNewsRemoteViewsService extends RemoteViewsService {

    @Override
    public RemoteViewsFactory onGetViewFactory(Intent intent) {
        return new MyListRemoteViewFactory();
    }
}

我想大概就是这样了。我希望我没有跳过任何东西。