Question

我正在开发一款可自动设置闹钟的应用。我已经google了很多，找到了一些解决方案并进行了一些更改并准备了代码，但这段代码无效。它始终是一个消息Alarm is null。

不知道为什么，任何人都可以帮我解决这个问题吗？提前致谢：

以下是代码：

AlarmManagerBroadcastReceiver类

import java.text.Format;
import java.text.SimpleDateFormat;
import java.util.Date;

import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.os.PowerManager;
import android.widget.Toast;

public class AlarmManagerBroadcastReceiver extends BroadcastReceiver {

 final public static String ONE_TIME = "oneTime";
 private Context contx; 

 public void AlarmManagerBroadcastReceiver()

 {

 }

 @Override
 public void onReceive(Context context, Intent intent) {
   PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
         PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "YOUR TAG");
         //Acquire the lock
         wl.acquire();

         //You can do the processing here.
         Bundle extras = intent.getExtras();
         StringBuilder msgStr = new StringBuilder();

         if(extras != null && extras.getBoolean(ONE_TIME, Boolean.FALSE)){
          //Make sure this intent has been sent by the one-time timer button.
          msgStr.append("One time Timer : ");
         }
         Format formatter = new SimpleDateFormat("hh:mm:ss a");
         msgStr.append(formatter.format(new Date()));

         Toast.makeText(context, msgStr, Toast.LENGTH_LONG).show();

         //Release the lock
         wl.release();
 }

 public void SetAlarm(Context context)
    {
        AlarmManager am=(AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
        Intent intent = new Intent(context, AlarmManagerBroadcastReceiver.class);
        intent.putExtra(ONE_TIME, Boolean.FALSE);
        PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent, 0);
        //After after 5 seconds
        am.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(), 1000 * 5 , pi); 
    }
}

主要活动：

import com.test.alarmtest.AlarmManagerBroadcastReceiver;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends Activity {

    private AlarmManagerBroadcastReceiver alarm;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);
        /*
         getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
            requestWindowFeature(Window.FEATURE_NO_TITLE);
            setContentView(new CameraPreview(this));
            */
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }


    public void alarm(View view) {

         AlarmManagerBroadcastReceiver alarmclock = new AlarmManagerBroadcastReceiver();
         if(alarm != null){
          alarm.SetAlarm(getBaseContext());
         }else{
          Toast.makeText(getBaseContext(), "Alarm is null", Toast.LENGTH_SHORT).show();
         }
        }

}

main.xml中

<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:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.test.cameraapp.MainActivity" >

    <Button
        android:id="@+id/button2"
        style="?android:attr/buttonStyleSmall"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/button1"
        android:layout_alignBottom="@+id/button1"
        android:layout_marginRight="23dp"
        android:layout_toLeftOf="@+id/button1"
        android:text="setAlarm"
        android:onClick="alarm" />

</RelativeLayout>

Answer 1

您正在检查alarm，但应检查alarmclock，因为这是您在此行中创建的内容：

AlarmManagerBroadcastReceiver alarmclock = new AlarmManagerBroadcastReceiver();

将您的if声明更改为以下

if(alarmclock != null) {
      alarmclock.SetAlarm(getBaseContext());
}
else {
      Toast.makeText(getBaseContext(), "Alarm is null", Toast.LENGTH_SHORT).show();
}

警报应用程序没有设置任何警报 - Android

1 个答案: