Question

我的代码已经运行，但它有问题。我怎么解决它。当我在timepickerdialog中第一次选择时（单击textview时间）。我按OK，按下切换按钮后，alarmmanager工作正常。我关闭了我的应用程序。然后再打开。我单击textview时间来显示我的timepickerdialog但我不选择另一个时间并单击取消。按下切换按钮，出现问题。我认为因为timepicker的值为null。我尝试了很多方法来解决它，但我不能。请帮帮我。这是我的代码 TextView显示TimePickerDialog。

 time.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            int hour = calendar.get(Calendar.HOUR_OF_DAY);
            int minute = calendar.get(Calendar.MINUTE);
            TimePickerDialog mTimePicker;
            mTimePicker = new TimePickerDialog(MainActivity.this, new TimePickerDialog.OnTimeSetListener() {
                @Override
                public void onTimeSet(TimePicker timePicker, int selectedHour, int selectedMinute) {
                    timePicker.setIs24HourView(true);
                    calendar.set(Calendar.HOUR_OF_DAY, selectedHour);
                    calendar.set(Calendar.MINUTE, selectedMinute);
                    calendar.set(Calendar.SECOND, 0);
                    get_hour = String.valueOf(selectedHour);
                    get_min = String.valueOf(selectedMinute);
                    if(selectedHour < 10 ){
                        get_hour = "0" + String.valueOf(selectedHour);
                    }
                    if(selectedMinute < 10) {
                        get_min = "0" + String.valueOf(selectedMinute);
                    }
                    millis = calendar.getTimeInMillis();
                    time.setText( get_hour + " : " + get_min);
                    savePrefs();
                }
            }, hour, minute, true);
            mTimePicker.setTitle("Pick Time");
            onoff_alarm.setChecked(false);
            mTimePicker.show();
        }
    });

这是我的切换按钮。

onoff_alarm.setOnCheckedChangeListener(new OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                if(onoff_alarm.isChecked()) {
                    if (get_hour.equals(null) && get_min.equals(null)){
                        Toast.makeText(getApplicationContext(), "Choose Another Time Please !", Toast.LENGTH_SHORT).show();
                        onoff_alarm.setChecked(false);
                    }else  {
                        my_intent.putExtra("extra", "alarm on");
                        Toast.makeText(getApplicationContext(), " Set time when " + get_hour + " Hour " + get_min + " Min ", Toast.LENGTH_SHORT).show();
                        pending_intent = PendingIntent.getBroadcast(MainActivity.this, 0, my_intent, PendingIntent.FLAG_UPDATE_CURRENT);
                        alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, millis, AlarmManager.INTERVAL_DAY, pending_intent);
                    }
                }
                else {
                    my_intent.putExtra("extra","alarm off");
                    Toast.makeText(getApplicationContext(), "Cancel set time", Toast.LENGTH_SHORT).show();
                    alarmManager.cancel(pending_intent);
                    sendBroadcast(my_intent);
                }
                savePrefs();
            }
    });
}

我使用过像这样的SharePreferences：

public void savePrefs(){
    SharedPreferences sharepreferences = getSharedPreferences(PREFS, Context.MODE_PRIVATE);
    String hour_set = String.valueOf(get_hour);
        String min_set = String.valueOf(get_min);
    SharedPreferences.Editor editor = sharepreferences.edit();
    editor.putString(Hoursave, hour_set);
    editor.putString(Minsave, min_set);
        editor.commit();

public void loadPrefs(){

    SharedPreferences sharepreferences = getSharedPreferences(PREFS, Context.MODE_PRIVATE);
    String hour_x = sharepreferences.getString(Hoursave, "");
        String min_x = sharepreferences.getString(Minsave, "");
    time.setText(hour_x + " : " + min_x);

Answer 1

当您“关闭”应用程序时，将从系统中删除待处理的警报。您可以通过adb中的以下命令检查 -

adb shell dumpsys alarm

要解决此问题，请在设置警报时将警报时间存储在SharedPreferences中（最简单的方法，但如果您已经在使用DB，也可以选择数据库表）。接下来，当从已杀死状态重新打开应用程序时，只需通过从SharedPreferences（或DB）读取时间并使用相同的警报ID再次创建警报。

我如何用alarmmanager解决Timepickerdialog的“值null”？

1 个答案: