java - onDateChanged 和 onCheckedChanged 一起工作
问题描述
在一项活动中,我有一个 datePicker(微调器),允许用户选择他们的出生日期,在此之下,用户还必须选择他们的性别。我有一个按钮,一旦设置了两个值(日期和性别),就会启用该按钮。我面临的问题是启用该按钮,尽管首先更改了哪个值。目前,用户必须选择他们的出生日期,然后选择他们的性别才能激活按钮。无论首先更改哪个值,我都希望启用该按钮。
这是我的代码:
final RadioGroup rGroup = findViewById(R.id.gender_radio_group);
RadioButton female_radio_button = rGroup.findViewById(rGroup.getCheckedRadioButtonId());
RadioButton male_radio_button = rGroup.findViewById(rGroup.getCheckedRadioButtonId());
RadioButton non_binary_radio_button = rGroup.findViewById(rGroup.getCheckedRadioButtonId());
//Check if datePicker and gender radiobutton has been used, if true enable button
calendar.setTimeInMillis(System.currentTimeMillis());
datePicker_birthday.init(calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH),
calendar.get(Calendar.DAY_OF_MONTH), new DatePicker.OnDateChangedListener() {
@Override
public void onDateChanged(DatePicker datePicker, int year, int month, int dayOfMonth) {
// This overrides the radiogroup onCheckListener
rGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
public void onCheckedChanged(RadioGroup group, int checkedId) {
// This will get the radiobutton that has changed in its check state
RadioButton checkedRadioButton = group.findViewById(checkedId);
// This puts the value (true/false) into the variable
boolean isChecked = checkedRadioButton.isChecked();
// If the radiobutton that has changed in check state is now checked...
if (isChecked) {
continue_register_birthday_gender_button.setEnabled(true);
continue_register_birthday_gender_button.setBackground(ContextCompat.getDrawable(RegisterBirthDateAndGenderActivity.this,
R.drawable.button_active));
}
}
});
}
});
解决方案
您的代码几乎没有问题。
如果用户首先选择单选按钮选择,则不会触发 rGroup.setOnCheckedChangeListener()。需要迁移到 onDateChanged() 之外。
重新定位后,它也不起作用,因为无线电组侦听器不知道 datePicker 条目是否也被更改。
用户可以选择先更新性别,再更新日期,反之亦然。可能的解决方案如下:
查看fixme
评论。
// fixme: Add class variables (booleans) to keep track of changed ui items
private Boolean isDatePickerOnDateChanged = false;
private Boolean isRadioGroupOnCheckedChanged = false;
// fixme: Re-locate rGroup.setOnCheckedChangeListener(..) to here.
RadioButton non_binary_radio_button = rGroup.findViewById(rGroup.getCheckedRadioButtonId());
rGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
public void onCheckedChanged(RadioGroup group, int checkedId) {
//...
isRadioGroupOnCheckedChanged = true;
if (isDatePickerOnDateChanged && isRadioGroupOnCheckedChanged) {
continue_register_birthday_gender_button.setEnabled(true);
}
// fixme: Remove previous rGroup.setOnCheckedChangeListener(..) inside onDateChanged() to above
datePicker_birthday.init(... {
@Override
public void onDateChanged(DatePicker datePicker, int year, int month, int dayOfMonth) {
//...
isDatePickerOnDateChanged = true;
if (isDatePickerOnDateChanged && isRadioGroupOnCheckedChanged) {
continue_register_birthday_gender_button.setEnabled(true);
}
- 上述解决方案中的一些冗余代码:
isRadioGroupOnCheckedChanged = true;
if (isDatePickerOnDateChanged && isRadioGroupOnCheckedChanged) {
continue_register_birthday_gender_button.setEnabled(true);
}
可以简化为
isRadioGroupOnCheckedChanged = true;
if (isDatePickerOnDateChanged) {
continue_register_birthday_gender_button.setEnabled(true);
}
因为&& isRadioGroupOnCheckedChanged
总是正确的,因为之前的陈述isRadioGroupOnCheckedChanged = true;
。