如何创建带有选项的 Android 小部件?

How to create an Android widget with options?

我正在为我的笔记应用程序开发小部件。

我要存档的类似colorNote插件:

  1. Select笔记应用小工具

  2. 允许用户选择存储在 Sqlite 中的可用笔记列表

  3. 显示带有 selected 注释内容的小部件。

我可以显示简单的小部件来显示我想要的简单消息,但我想做的是允许用户 select 从笔记列表中指定一条笔记作为小部件的内容。我很难找到相关资源,如果您知道某个搜索关键字,请告诉我,我会自己进行研究。

我认为 ColorNote 使用的是 Widget Configuration Activity。 您可以在第一个 link(这是官方的)上找到一个有用的示例,或者(为什么不)也可以在 there.

上找到一个有用的示例

要实现 "dialog" 样式,您必须像这样设置小部件配置 activity:

<activity
 ...
 android:theme="@android:style/Theme.Dialog"
 android:excludeFromRecents="true" />

以上示例取自this answer

如果您想了解更多有关小部件设计的信息,请同时查看 there

例子

1) 创建widget_info并将其放入res/xml文件夹:

<?xml version="1.0" encoding="utf-8"?>
<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"
    android:configure="com.mycompany.app.widgettest.WidgetConfigureActivity"
    android:initialKeyguardLayout="@layout/widget"
    android:initialLayout="@layout/widget"
    android:minHeight="40dp"
    android:minWidth="40dp"
    android:resizeMode="horizontal|vertical"
    android:updatePeriodMillis="86400000"
    android:widgetCategory="home_screen">

</appwidget-provider>

2) 创建您的 小部件 布局(我选择了最简单的布局):

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#09C"
    android:padding="@dimen/widget_margin">

    <TextView
        android:id="@+id/appwidget_text"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:layout_margin="8dp"
        android:background="#09C"
        android:contentDescription="@string/appwidget_text"
        android:text="@string/appwidget_text"
        android:textColor="#ffffff"
        android:textSize="24sp"
        android:textStyle="bold|italic" />

</RelativeLayout>

随意赋予它自己的风格。

3) 创建 widget_configure activity 布局:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:padding="16dp">

    <TextView
        android:id="@+id/text_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:text="@string/configure" />

    <EditText
        android:id="@+id/appwidget_text"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:inputType="text"
        android:layout_below="@+id/text_view"/>

    <ListView
        android:id="@+id/list"
        android:layout_height="wrap_content"
        android:layout_width="match_parent"
        android:layout_below="@+id/appwidget_text"
        android:layout_above="@+id/add_button">
    </ListView>

    <Button
        android:id="@+id/add_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:text="@string/add_widget"
        android:layout_alignParentBottom="true" />

</RelativeLayout>

还有,由您决定样式和编辑 activity 的布局;在上面的示例中,我添加了一个编辑文本,它将创建一个 "new" 注释(但它不会保存在数据库中)和一个包含虚拟内容的列表。由您来填充您的列表,当然是从您的数据库中获取的。

4) 将小部件配置 activity 和小部件提供程序添加到清单中(在 application 标记内):

        <receiver android:name=".AppWidget">
            <intent-filter>
                <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
            </intent-filter>

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

        <activity
            android:name=".WidgetConfigureActivity"
            android:theme="@android:style/Theme.Dialog"
            android:excludeFromRecents="true">
            <intent-filter>
                <action android:name="android.appwidget.action.APPWIDGET_CONFIGURE" />
            </intent-filter>
        </activity>

5) 创建将扩展AppWidgetProvider 的class AppWidget(注意应用程序小部件配置在以下class、WidgetConfigureActivity 中实现和管理) [我没有添加任何特别的东西 class]:

import android.appwidget.AppWidgetProvider;
import android.appwidget.AppWidgetManager;
import android.content.Context;
import android.widget.RemoteViews;

/**
 * Implementation of App Widget functionality.
 */
public class AppWidget extends AppWidgetProvider {

    @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);
        }
    }

    @Override
    public void onDeleted(Context context, int[] appWidgetIds) {
        // When the user deletes the widget, delete the preference associated with it.
        for (int appWidgetId : appWidgetIds) {
            WidgetConfigureActivity.deleteTitlePref(context, appWidgetId);
        }
    }

    @Override
    public void onEnabled(Context context) {
        // Enter relevant functionality for when the first widget is created
    }

    @Override
    public void onDisabled(Context context) {
        // Enter relevant functionality for when the last widget is disabled
    }

    static void updateAppWidget(Context context, AppWidgetManager appWidgetManager,
                                int appWidgetId) {

        CharSequence widgetText = WidgetConfigureActivity.loadTitlePref(context, appWidgetId);
        // Construct the RemoteViews object
        RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.widget);
        views.setTextViewText(R.id.appwidget_text, widgetText);

        // Instruct the widget manager to update the widget
        appWidgetManager.updateAppWidget(appWidgetId, views);
    }
}

6) 最后,这是 WidgetConfigureActivity:

import android.app.Activity;
import android.appwidget.AppWidgetManager;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;

/**
 * The configuration screen for the {@link AppWidget} com.bepatient.app.widgettest.AppWidget.
 */
public class WidgetConfigureActivity extends Activity {

    int mAppWidgetId = AppWidgetManager.INVALID_APPWIDGET_ID;
    EditText mAppWidgetText;
    private static final String PREFS_NAME = "AppWidget";
    private static final String PREF_PREFIX_KEY = "appwidget";

    public WidgetConfigureActivity() {
        super();
    }

    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);

        // Set the result to CANCELED.  This will cause the widget host to cancel
        // out of the widget placement if the user presses the back button.
        setResult(RESULT_CANCELED);

        setContentView(R.layout.widget_configure);
        // Set layout size of activity
        getWindow().setLayout(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
        mAppWidgetText = (EditText) findViewById(R.id.appwidget_text);
        findViewById(R.id.add_button).setOnClickListener(mOnClickListener);
        final ListView listView = (ListView) findViewById(R.id.list);

        // Defined array values to show in ListView
        String[] values = new String[] { "Don't forget the milk!",
                "Do not forget to go get the mother-in-law",
                "Go to the laundry",
                "Marise number 0123456789"
        };

        ArrayAdapter<String> adapter = new ArrayAdapter<>(this,
                android.R.layout.simple_list_item_1, android.R.id.text1, values);

        listView.setAdapter(adapter);

        // ListView Item Click Listener
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                // Take ListView clicked item value
                String  widgetText    = (String) listView.getItemAtPosition(position);
                createWidget(getApplicationContext(), widgetText);
            }
        });

        // Find the widget id from the intent.
        Intent intent = getIntent();
        Bundle extras = intent.getExtras();
        if (extras != null) {
            mAppWidgetId = extras.getInt(
                    AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID);
        }

        // If this activity was started with an intent without an app widget ID, finish with an error.
        if (mAppWidgetId == AppWidgetManager.INVALID_APPWIDGET_ID) {
            finish();
            return;
        }

        mAppWidgetText.setText(loadTitlePref(WidgetConfigureActivity.this, mAppWidgetId));
    }

    View.OnClickListener mOnClickListener = new View.OnClickListener() {
        public void onClick(View v) {
            final Context context = WidgetConfigureActivity.this;

            // When the button is clicked, get text
            String widgetText = mAppWidgetText.getText().toString();
            createWidget(context, widgetText);
        }
    };

    private void createWidget(Context context, String widgetText) {
        // Store the string locally
        saveTitlePref(context, mAppWidgetId, widgetText);

        // It is the responsibility of the configuration activity to update the app widget
        AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
        AppWidget.updateAppWidget(context, appWidgetManager, mAppWidgetId);

        // Make sure we pass back the original appWidgetId
        Intent resultValue = new Intent();
        resultValue.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, mAppWidgetId);
        setResult(RESULT_OK, resultValue);
        finish();
    }

    // Write the prefix to the SharedPreferences object for this widget
    static void saveTitlePref(Context context, int appWidgetId, String text) {
        SharedPreferences.Editor prefs = context.getSharedPreferences(PREFS_NAME, 0).edit();
        prefs.putString(PREF_PREFIX_KEY + appWidgetId, text);
        prefs.apply();
    }

    // Read the prefix from the SharedPreferences object for this widget.
    // If there is no preference saved, get the default from a resource
    static String loadTitlePref(Context context, int appWidgetId) {
        SharedPreferences prefs = context.getSharedPreferences(PREFS_NAME, 0);
        String titleValue = prefs.getString(PREF_PREFIX_KEY + appWidgetId, null);
        if (titleValue != null) {
            return titleValue;
        } else {
            return context.getString(R.string.appwidget_text);
        }
    }

    static void deleteTitlePref(Context context, int appWidgetId) {
        SharedPreferences.Editor prefs = context.getSharedPreferences(PREFS_NAME, 0).edit();
        prefs.remove(PREF_PREFIX_KEY + appWidgetId);
        prefs.apply();
    }
}

在此 class 中,您将必须管理和填充保存在您的应用数据库中的所有笔记。当您单击按钮或项目时,方法 createWidget 将为您完成工作。

注意以下行:

// Set layout size of activity
getWindow().setLayout(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);

这必须在 setContentView() 方法之后调用,否则您的 activity 会很小很小。如果你 运行 这个例子,你会发现配置 activity 有一个简单的风格,所以你必须根据你的应用程序 UI 创建你自己的风格(如果你想要!) .

您可以为您的小部件开发设置功能,该功能将在小部件实例化或单击小部件时显示。要为您的小部件提供选项功能,您必须在您的应用程序中创建设置 activity,其中 UI 包含供用户使用的选项 select 和 activity 包含处理设置的行为select离子。

每次用户保存 selection 时,您都可以将 selected 选项应用于小部件实例。有关示例的详细说明,请参阅 http://www.zoftino.com/android-widget-example