Question

我正在创建一个Android应用，我使用DatePickerDialog和TimePickerDialog来获取用户的特定时间，并RadioButton知道是否符合要求。如果时间超过3天，少于3周并且检查RadioButton“是”，我想激活一个按钮。

我使用DialogFragment来获取用户的日期和时间以及更新布局。

MainActivity：

public void showDatePickerDialog(View v) {
    DialogFragment newFragment = new DatePickerFragment();
    newFragment.show(getFragmentManager(), "datePicker");
}

public void showTimePickerDialog(View v) {
    DialogFragment newFragment = new TimePickerFragment();
    newFragment.show(getFragmentManager(), "timePicker");
}

public void onRadioButtonClicked(View v) {
    // Is the button now checked?
    boolean checked = ((RadioButton) v).isChecked();

    // Check which radio button was clicked
    switch (v.getId()) {
        case R.id.yes:
            if (checked)
                test_button.setEnabled(true);
                test_button.setAlpha(1);
            break;
        case R.id.no:
            if (checked)
                test_button.setEnabled(false);
                test_button.setAlpha(.5f);
            break;
    }
}

DatePickerFragment：

public class DatePickerFragment extends DialogFragment
    implements DatePickerDialog.OnDateSetListener {

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        // Use the current date as the default date in the picker
        final Calendar c = Calendar.getInstance();
        int year = c.get(Calendar.YEAR);
        int month = c.get(Calendar.MONTH);
        int day = c.get(Calendar.DAY_OF_MONTH);

        // Create a new instance of DatePickerDialog and return it
        return new DatePickerDialog(getActivity(), this, year, month, day);
    }

    public void onDateSet(DatePicker view, int year, int month, int day) {
        Calendar cal = Calendar.getInstance();
        cal.set(year, month, day);
        Log.w("DatePicker", "Date = " + year + month + year);

        // Update date in the view
        ((TextView) getActivity().findViewById(R.id.dateTextView)).setText(day + " / " + month);
    }
    ...
}

这适用于RadioButton，但我无法理解如何将日期和时间作为条件的一部分。每当我更改日期，时间或条件时，必须评估按钮是否将被激活或停用。

有什么建议吗？

Answer 1

完美日期场景的简单java示例

    //after 3 days date
    Calendar  cal3Days=Calendar.getInstance();
    cal3Days.add(Calendar.DAY_OF_YEAR, 3);

    //after 3 weeks date
    Calendar cal3Weeks=Calendar.getInstance();
    cal3Weeks.add(Calendar.WEEK_OF_YEAR, 3);

    //after 3 weeks and plus 1 day
    Calendar cal3Weeks1day=Calendar.getInstance();
    cal3Weeks1day.add(Calendar.WEEK_OF_YEAR, 3);
    cal3Weeks1day.add(Calendar.DAY_OF_YEAR, 1);


    //your selected date 
    Calendar selectedDate=Calendar.getInstance();
    selectedDate.add(Calendar.WEEK_OF_YEAR, 3);//change int value to test
    selectedDate.add(Calendar.DAY_OF_YEAR, 3);//change int value to test

    if(selectedDate.after(cal3Days) && selectedDate.before(cal3Weeks) && !selectedDate.after(cal3Weeks1day)){
        System.out.println("Yes after 3 days and before 3 weeks");//valid selection
    }else{
        System.out.println("No Valid selection");
    }

Answer 2

我使用DatePickerFragmentListener解决了这个问题。当MainActivity中的片段onDateSet更改日期或时间时，将更新时间和日期，并检查它是否在时间间隔内＆gt; 4小时＆lt; 2周。按钮状态将相应更改，如果用户选择了间隔之外的日期或未选中复选框，则使用Toast。

DatePickerFragment：

public interface DatePickerFragmentListener {
    void onDateSet(Calendar cal);
}

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    // Use the current date as the default date in the picker
    final Calendar c = Calendar.getInstance();
    int year = c.get(Calendar.YEAR);
    int month = c.get(Calendar.MONTH);
    int day = c.get(Calendar.DAY_OF_MONTH);

    // Create a new instance of DatePickerDialog and return it
    // If you're alive you can't be born in the future
    DatePickerDialog dialog = new DatePickerDialog(getActivity(), this, year, month, day);
    dialog.getDatePicker().setMaxDate(System.currentTimeMillis());
    return dialog;
}

public void onDateSet(DatePicker view, int year, int month, int day) {
    Calendar cal = Calendar.getInstance();
    cal.set(year, month, day, 0, 0);
    Log.w("DatePicker", "Date = " + year + month + year);

    // Update date in the view
    ((TextView) getActivity().findViewById(R.id.dateTextView)).setText(
            cal.getDisplayName(Calendar.MONTH, Calendar.LONG, Locale.ENGLISH ) + " " + day);

    // Update listeners
    DatePickerFragmentListener activity = (DatePickerFragmentListener) getActivity();
    activity.onDateSet(cal);
    this.dismiss();
}

MainActivity：

private Calendar birthDate;
private Calendar birthDay;
private Calendar birthTime;
private Calendar cal4Hours;
private Calendar cal2Weeks;

@Override
public void onDateSet(Calendar cal) {
    this.birthDay = cal;
    this.birthDay.clear(Calendar.HOUR_OF_DAY);
    this.birthDay.clear(Calendar.HOUR);
    this.birthDay.clear(Calendar.MINUTE);
    calculateBirthDate();
    updateButtonState();
}

@Override
public void onTimeSet(Calendar cal) {
    this.birthTime = cal;
    calculateBirthDate();
    updateButtonState();
}

public void calculateBirthDate() {
    if (this.birthDay == null || this.birthTime == null) {
        // Do nothing
    } else {
        this.birthDate = (Calendar) this.birthDay.clone();
        this.birthDate.set(Calendar.HOUR_OF_DAY, this.birthTime.get(Calendar.HOUR_OF_DAY));
        this.birthDate.set(Calendar.HOUR, this.birthTime.get(Calendar.HOUR));
        this.birthDate.set(Calendar.AM_PM, this.birthTime.get(Calendar.AM_PM));
        this.birthDate.set(Calendar.MINUTE, this.birthTime.get(Calendar.MINUTE));
    }
}

public boolean isBirthDateWithinRange() {
    // Reset from and to range
    this.cal4Hours = (Calendar) birthDate.clone();
    this.cal2Weeks = (Calendar) birthDate.clone();
    cal4Hours.add(Calendar.HOUR_OF_DAY, 4);
    cal2Weeks.add(Calendar.WEEK_OF_YEAR, 2);

    Calendar now = Calendar.getInstance();

    if (now.after(cal4Hours) && now.before(cal2Weeks)) {
        return true;
    } else {
        return false;
    }
}


public void updateButtonState() {
    if (birthDay == null || birthTime == null || lowBirthWeight == null) {
        // do nothing
        test_button.setEnabled(false);
        test_button.setAlpha(.5f);
    } else if (!isBirthDateWithinRange()) {
            Toast.makeText(this, "Your child is too young or old to use the app",
                    Toast.LENGTH_LONG).show();
        test_button.setEnabled(false);
        test_button.setAlpha(.5f);
    } else if (lowBirthWeight == true) {
        Toast.makeText(this,
                "The birth weight has to be more than 2.5 kg for the app to work",
                Toast.LENGTH_LONG).show();
        test_button.setEnabled(false);
        test_button.setAlpha(.5f);
    } else {
        // Enable button
        test_button.setEnabled(true);
        test_button.setAlpha(1);
    }
}

如果日期来自给定范围并且单选按钮为“是”，如何激活按钮？

2 个答案: