Blackberry - How to center the datepicker popup for DateField - blackberry

Question

I have DateField in center of my screen
And when I touch it I see:
But I want to see:
My question is:
How can I center the datepicker popup for DateField?
Blackberry OS 6
Update:
public class MyMainScreen extends MainScreen
{
protected DateField dateField_ = null;
protected VerticalFieldManager container_ = null;
public MyMainScreen()
{
super();
container_ = new VerticalFieldManager(VerticalFieldManager.VERTICAL_SCROLL
| VerticalFieldManager.VERTICAL_SCROLLBAR | VerticalFieldManager.USE_ALL_HEIGHT)
{
protected void sublayout(int width, int height)
{
super.sublayout(width, height);
layoutChild(dateField_ , 100, 40);
setPositionChild(dateField_ , (width - 100) / 2, 50);
setVirtualExtent(width, 50);
}
};
add(container_);
dateField_ = new DateField("", new Date(), new SimpleDateFormat("HH:mm"), Field.FIELD_HCENTER |
DrawStyle.HCENTER | Field.FOCUSABLE);
container_.add(dateField_);
add(container_);
}
}

Answer 1

Ok, so there's a few problems:
the DateField won't center the field just because you pass Field.FIELD_HCENTER | DrawStyle.HCENTER into the constructor. I don't think DateField even recognizes those flags.
A VerticalFieldManager is a special Manager that's designed to lay out its children vertically from top-to-bottom in the order you add() them. If you're not going to lay out the fields that way, then I don't know that you should extend VerticalFieldManager. Just extend Manager directly, if you want to implement sublayout(). Also, calling super.sublayout() in your implementation might cause issues.
You are hardcoding the height/width of your DateField. I'm not sure it allows that.
Your code didn't actually compile for me, as the DateField constructor takes a long date, not a Date. That doesn't have anything to do with centering though.
So, I'd recommend something like this:
super(MainScreen.VERTICAL_SCROLL | MainScreen.VERTICAL_SCROLLBAR);
dateField_ = new DateField("", (new Date()).getTime(), new SimpleDateFormat("HH:mm"), Field.FOCUSABLE);
container_ = new Manager(Manager.VERTICAL_SCROLL | Manager.VERTICAL_SCROLLBAR) {
public int getPreferredHeight() {
return Display.getHeight();
}
public int getPreferredWidth() {
return Display.getWidth();
}
protected void sublayout(int width, int height) {
int h = Math.min(height, Display.getHeight());
setExtent(width, h);
// only needed if there's actually more content than fits in the visible area
//setVirtualExtent(width, h + ?);
int dfWidth = dateField_.getPreferredWidth();
int dfHeight = dateField_.getPreferredHeight();
layoutChild(dateField_, dfWidth, dfHeight);
setPositionChild(dateField_, (width - dfWidth) / 2, (h - dfHeight) / 2);
}
};
container_.add(dateField_);
add(container_);
P.S. I wasn't sure if you wanted scrolling or not. With only a DateField, there's no reason to scroll. But, I know your real Screen probably has more content, so you may need to setVirtualExtent(), which I've commented out.

Answer 2

This solution works for me also:
package com.my.package;
import java.util.Calendar;
import java.util.Date;
import net.rim.device.api.i18n.SimpleDateFormat;
import net.rim.device.api.ui.DrawStyle;
import net.rim.device.api.ui.Field;
import net.rim.device.api.ui.Manager;
import net.rim.device.api.ui.TouchEvent;
import net.rim.device.api.ui.UiApplication;
import net.rim.device.api.ui.component.DateField;
import net.rim.device.api.ui.container.VerticalFieldManager;
import net.rim.device.api.ui.picker.DateTimePicker;
public class MyDateManager extends VerticalFieldManager {
protected DateField dateField_ = null;
protected DateTimePicker dateTimePicker_ = null;
protected SimpleDateFormat dateFormat_ = null;
public MyDateManager() {
super(Manager.FIELD_HCENTER | Manager.FIELD_VCENTER);
dateFormat_ = new SimpleDateFormat("HH:mm");
dateField_ = new DateField("", new Date().getTime(), dateFormat_,
Field.FIELD_HCENTER | DrawStyle.HCENTER | Field.FOCUSABLE) {
protected boolean touchEvent(TouchEvent paramTouchEvent) {
if (paramTouchEvent.getEvent() == TouchEvent.CLICK) {
dateField_.setEnabled(false);
showDatePicker();
}
return super.touchEvent(paramTouchEvent);
}
protected boolean trackwheelClick(int paramInt1, int paramInt2) {
dateField_.setEnabled(false);
showDatePicker();
return super.trackwheelClick(paramInt1, paramInt2);
}
};
this.add(dateField_);
}
protected void sublayout(int width, int height) {
layoutChild(dateField_, width, height);
setPositionChild(dateField_, (width - dateField_.getWidth()) / 2,
(height - dateField_.getHeight()) / 2);
int h = dateField_.getHeight();
if (h <= 0)
h = height;
setExtent(width, h);
}
protected void showDatePicker() {
if (dateTimePicker_ == null) {
Calendar cal = Calendar.getInstance();
// HACK
String dateFormat = dateFormat_.toPattern().indexOf("H", 0) == -1 ? dateFormat_
.toPattern() : null;
String timeFormat = dateFormat_.toPattern().indexOf("H", 0) != -1 ? dateFormat_
.toPattern() : null;
dateTimePicker_ = DateTimePicker.createInstance(cal, dateFormat,
timeFormat);
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
if (dateTimePicker_.doModal()) {
dateField_.setDate(dateTimePicker_.getDateTime()
.getTime());
}
dateField_.setEnabled(true);
dateField_.setFocus();
dateTimePicker_ = null;
}
});
}
}
}