Question

我试图用日期和时间设置闹钟。一切都很好，但在我设置闹钟之后，我想要的通知出现在我之前设置的时间（分钟）之前。

* ViewNote.java：

    private DatePicker datePicker;
    private TimePicker timePicker;
    private Calendar dateTime;
    private final static int REMINDER_RQS_CODE = 1;

    ...
    ...

@Override
    public boolean onCreateOptionsMenu(Menu menu) {

        getMenuInflater().inflate(R.menu.menu_view_note, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {

        switch(item.getItemId())
        {
case R.id.set_reminder:
                datePicker = (DatePicker) findViewById(R.id.datePicker);
                timePicker = (TimePicker) findViewById(R.id.timePicker);

                Calendar now = Calendar.getInstance();

                if(datePicker != null)
                {
                    datePicker.init(Calendar.YEAR,
                            Calendar.MONTH,
                            Calendar.DAY_OF_MONTH,
                            null);
                }

                if(timePicker != null)
                {
                    timePicker.setCurrentHour(now.get(Calendar.HOUR_OF_DAY));
                    timePicker.setCurrentMinute(now.get(Calendar.MINUTE));
                }

                AlertDialog.Builder setDateDialog = new AlertDialog.Builder(this)
                        .setView(R.layout.date_picker_dialog)
                        .setTitle("Pick date")
                        .setIcon(R.drawable.context_menu)
                        .setPositiveButton("Next", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialogInterface, int i) {

                                dateTime = Calendar.getInstance();
                                if(datePicker != null)
                                {
                                    dateTime.set(datePicker.getYear(),
                                            datePicker.getMonth(),
                                            datePicker.getDayOfMonth());
                                }

                                AlertDialog.Builder setTimeDialog = new AlertDialog.Builder(ViewNote.this)
                                        .setView(R.layout.time_picker_dialog)
                                        .setTitle("Pick time")
                                        .setIcon(R.drawable.context_menu)
                                        .setPositiveButton(R.string.ok, new DialogInterface.OnClickListener() {
                                            @Override
                                            public void onClick(DialogInterface dialogInterface, int i) {

                                                dateTime = Calendar.getInstance();
                                                if(timePicker != null)
                                                {
                                                    dateTime.set(timePicker.getCurrentHour(),
                                                            timePicker.getCurrentMinute(),
                                                            00);
                                                }

                                                setReminder(dateTime);
                                            }
                                        });
                                setTimeDialog.show();
                            }
                        });
                        setDateDialog.show();
                return true;
        }

        return super.onOptionsItemSelected(item);
    }

private void setReminder(Calendar dateTime)
    {
        Intent intent = new Intent(ViewNote.this, RemainderReceiver.class);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(ViewNote.this, REMINDER_RQS_CODE, intent, 0);
        AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
        alarmManager.set(AlarmManager.RTC_WAKEUP, dateTime.getTimeInMillis(), pendingIntent);
    }

* date_picker_dialog.xml：

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

    <DatePicker
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/datePicker"
        android:layout_gravity="center_horizontal" />

</LinearLayout>

* time_picker_dialog.xml：

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

    <TimePicker
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/timePicker"
        android:layout_gravity="center_horizontal" />
</LinearLayout>

* ReminderReceiver.java：

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;

public class RemainderReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {

        /*Intent intent1 = new Intent(context, MyReminderService.class);
        context.startService(intent1);*/

        Log.i("ReminderReceiver", "onReceive method called");

        try
        {
            Utils.generateNotification(context);
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }

    }
}

* MyReminderService.java：

import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.support.annotation.Nullable;

public class MyReminderService extends Service {

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

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

    @Override
    public void onStart(Intent intent, int startId) {
        super.onStart(intent, startId);
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
    }
}

* AndroidManifest.xml：

...
...

<uses-permission android:name="android.permission.WAKE_LOCK" />

    ...
    ...

    <service android:name=".MyReminderService"
                android:enabled="true" />

            <receiver android:name=".RemainderReceiver"/>
        </application>

    </manifest>

Answer 1

对我来说，似乎你在onClick的“PositiveButton”中调用了Calendar的错误方法。你打电话给：

dateTime.set(
    timePicker.getCurrentHour(),
    timePicker.getCurrentMinute(),
    00);

它没有设置小时，分钟和毫秒。相反，这种java.util.Calendar方法被调用，导致无意义的值：

public final void set(int year,
    int month,
    int date)

见这里：https://docs.oracle.com/javase/7/docs/api/java/util/Calendar.html#set%28int,%20int,%20int%29

您可以通过将TimePicker的时间转换为毫秒来修复此问题，并将其添加到“dateTime”的时间，如下所示。

dateTime = Calendar.getInstance();
if(timePicker != null)
{
    dateTime.setTimeInMillis(
        dateTime.getTimeInMillis()
        + (timePicker.getCurrentHour() * 360000)
        + (timePicker.getCurrentMinute() * 60000));
}
setReminder(dateTime);

当然1小时是60分钟，360秒是360000毫秒，1分钟是60秒，是60000毫秒。

的onReceive（）;方法在我设置的时间之前执行

1 个答案: