为什么 Android Studio 中的调度程序不起作用

Question

我正在尝试每天在特定时间安排通知，但它不起作用。 我正在使用在线教程尝试此操作，但仍然无法正常工作。 我不确定是什么问题。 我在这里附上了所有的代码。

MainActivity.java

package com.example.alarm;

import androidx.appcompat.app.AppCompatActivity;

import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.os.SystemClock;
import android.view.View;
import android.widget.Button;

import java.util.Calendar;

public class MainActivity extends AppCompatActivity {

    Button show;

    public static String MY_PREFS_NAME= "nameOfSharedPreferences";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        show = findViewById(R.id.btn_show);


        show.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startAlarm(true,true);
            }
        });

    }

    private void startAlarm(boolean isNotification, boolean isRepeat) {
        AlarmManager manager = (AlarmManager) MainActivity.this.getSystemService(Context.ALARM_SERVICE);
        Intent myIntent;
        PendingIntent pendingIntent;

        // SET TIME HERE
        Calendar calendar= Calendar.getInstance();
        //calendar.setTimeInMillis(System.currentTimeMillis());
        calendar.set(Calendar.HOUR_OF_DAY,17);
        calendar.set(Calendar.MINUTE, 12);


        myIntent = new Intent(MainActivity.this,AlarmNotificationReceiver.class);
        pendingIntent = PendingIntent.getBroadcast(this,0,myIntent,0);
        myIntent.setAction("MY_NOTIFICATION_MESSAGE");

        if(!isRepeat) {
            //assert manager != null;
            manager.set(AlarmManager.RTC_WAKEUP, SystemClock.elapsedRealtime()+3000,pendingIntent);
        }
        else {
            //assert manager != null;
            manager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), AlarmManager.INTERVAL_DAY,pendingIntent);
        }
    }
}

AlarmNotificationReceiver.java

package com.example.alarm;

import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;

import static android.app.PendingIntent.FLAG_ONE_SHOT;

public class AlarmNotificationReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        Notification.Builder builder = new Notification.Builder(context);

        Intent myIntent = new Intent(context, MainActivity.class);
        PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, myIntent, FLAG_ONE_SHOT );

        builder.setAutoCancel(true)
                .setDefaults(Notification.DEFAULT_ALL)
                .setWhen(System.currentTimeMillis())
                .setSmallIcon(R.mipmap.ic_launcher)
                .setContentTitle("Title")
                .setContentIntent(pendingIntent)
                .setContentText("Description")
                .setDefaults(Notification.DEFAULT_LIGHTS | Notification.DEFAULT_SOUND)
                .setContentInfo("Info")
                .build();

        NotificationManager notificationManager = (NotificationManager)context.getSystemService(Context.NOTIFICATION_SERVICE);
        if (intent.getAction().equals("MY_NOTIFICATION_MESSAGE")) {
            notificationManager.notify(100,builder.build());
            Log.i("Notify", "Alarm"); //Optional, used for debuging.
        }
    }
}

MyService.java

package com.example.alarm;

import android.app.AlarmManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.os.IBinder;
import android.os.SystemClock;

import java.util.Calendar;

public class MyService extends Service {
    public MyService() {
    }

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        startAlarm(true,true);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        return START_NOT_STICKY;
    }

    private void startAlarm(boolean isNotification, boolean isRepeat) {
        AlarmManager manager = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
        Intent myIntent;
        PendingIntent pendingIntent;

        //THIS IS WHERE YOU SET NOTIFICATION TIME FOR CASES WHEN THE NOTIFICATION NEEDS TO BE RESCHEDULED
        Calendar calendar= Calendar.getInstance();
        //calendar.setTimeInMillis(System.currentTimeMillis());
        calendar.set(Calendar.HOUR_OF_DAY,18);
        calendar.set(Calendar.MINUTE,45);

        myIntent = new Intent(this,AlarmNotificationReceiver.class);
        pendingIntent = PendingIntent.getBroadcast(this,0,myIntent,0);


        if(!isRepeat)
            manager.set(AlarmManager.RTC_WAKEUP, SystemClock.elapsedRealtime()+3000,pendingIntent);
        else
            manager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), AlarmManager.INTERVAL_DAY,pendingIntent);
    }
}

BootReceiver.java

package com.example.alarm;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;

public class BootReceiver extends BroadcastReceiver {

    public void onReceive(Context context, Intent intent)
    {

        // Your code to execute when Boot Completd

        Intent i = new Intent(context,MyService.class);
        context.startService(i);

        Toast.makeText(context, "Booting Completed", Toast.LENGTH_LONG).show();

    }

}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="com.example.alarm">

    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
    <uses-permission android:name="android.permission.WAKE_LOCK" />
    <uses-permission android:name="android.permission.SET_ALARM"/>
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.WAKE_LOCK" />
    <uses-permission android:name="com.android.alarm.permission.SET_ALARM" />



    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">

    <receiver android:name=".BootReceiver"
        android:enabled="true"
        android:exported="true">
        <intent-filter>
            <action android:name="android.intent.action.BOOT_COMPLETED" />

            <category android:name="android.intent.category.HOME" />
        </intent-filter>
    </receiver>
    <receiver android:name=".AlarmNotificationReceiver"
              android:enabled="true"/>

        <service
            android:name=".MyService"
            android:enabled="true"
            android:exported="true"
            android:permission="TODO" />


        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

build.gradle(:app)

apply plugin: 'com.android.application'

android {
    compileSdkVersion 29
    buildToolsVersion "29.0.3"

    defaultConfig {
        applicationId "com.example.alarm"
        minSdkVersion 16
        targetSdkVersion 29
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }

}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])

    implementation 'androidx.appcompat:appcompat:1.2.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
}

Answer 1

您应该在发送PendingIntent之前放置myIntent.setAction （在MainActivity中）。 但是忘记它，因为启动后的广播接收器现在完全死了！