我创建了一个 DatePickerPreference,即我扩展了 DialogPreference 并在内部创建了一个 DatePicker 对象,并且让它几乎完美地工作。当您单击向上和向下箭头时,它会更改值并保存您选择的值。
但是,如果您单击字段内部并在其中键入新值,它不会保存更新的值!使用箭头时,始终会调用 onDateChanged() 方法;当用户输入字段并编辑它时,如果他选择另一个字段,它只会调用 onDateChanged (在这种情况下,如果他编辑最后一个字段并单击“确定”,则最后一次编辑将被忽略)。我找到Eric Besette 在他的 TimePickerPreference 中发布了类似的问题 http://www.ebessette.com/d/TimePickerPreference#comment-367
这是我的代码:
public class DatePickerPreference extends DialogPreference implements
OnDateChangedListener, OnDateSetListener {
@Override
protected View onCreateDialogView() {
DatePicker picker = new DatePicker(getContext());
mDate = getPersistedLong(System.currentTimeMillis());
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(mDate);
int day = calendar.get(Calendar.DAY_OF_MONTH);
int month = calendar.get(Calendar.MONTH);
int year = calendar.get(Calendar.YEAR);
picker.init(year, month, day, this);
return picker;
}
public void onDateChanged(DatePicker view, int year, int monthOfYear,
int dayOfMonth) {
mDate = (new Date(year - 1900, monthOfYear, dayOfMonth)).getTime();
}
public void onDateSet(DatePicker view, int year, int monthOfYear,
int dayOfMonth) {
onDateChanged(view, year, monthOfYear, dayOfMonth);
}
@Override
public void setDefaultValue(Object defaultValue) {
super.setDefaultValue(String.valueOf((
new Date(String.valueOf(defaultValue))).getTime()));
}
@Override
protected void onDialogClosed(boolean positiveResult) {
super.onDialogClosed(positiveResult);
if(positiveResult) {
if(isPersistent()) {
persistLong(mDate);
}
callChangeListener(String.valueOf(mDate));
}
}
public int getYear() { /*(...)*/ }
public int getMonth() { /*(...)*/ }
public int getDay() { /*(...)*/ }
public DatePickerPreference(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public DatePickerPreference(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
public void init() { setPersistent(true); }
public void setDate(Date date) { mDate = date.getTime(); }
public void setDate(long milisseconds) { mDate = milisseconds; }
public String getDate(int style) {
return DateFormat.getDateInstance(style).format(new Date(mDate));
}
public long getDate() { return mDate; }
private long mDate;
public static final int DATE_SHORT = DateFormat.SHORT;
public static final int DATE_MEDIUM = DateFormat.MEDIUM;
public static final int DATE_LONG = DateFormat.LONG;
public static final int DATE_FULL = DateFormat.FULL;
public static final int DATE_DEFAULT = DateFormat.DEFAULT;
}