Java Blackberry Refresh Field Label - blackberry

Question

I have a main class and a screen class. I have a button that launches a datepicker. When the datepicker is closed I need the label of the button to be refreshed with the selected value. How should I do that?
I tried with invalidate, creating a CustomButtonField that implements different onFocus, onUnFocus, and some other stuff but I guess I implemented them in a wrong way...
My two clases are these ones...
Main...
public class TestClass extends UiApplication
{
public static Calendar alarm1time = Calendar.getInstance(TimeZone.getTimeZone("GMT-3"));
public static void main(String[] args)
{
TestClass testClass = new TestClass ();
testClass.enterEventDispatcher();
}
public TestClass()
{
pushScreen(new TestClassScreen());
}
}
Screen...
public final class TestClassScreen extends MainScreen
{
public TestClassScreen()
{
ButtonField alarm1 = new ButtonField("Alarm : " + TestClass.alarm1time.get(Calendar.HOUR_OF_DAY) + ":" + TestClass.alarm1time.get(Calendar.MINUTE) ,ButtonField.FOCUSABLE)
{
public boolean navigationClick (int status , int time)
{
datePicker(1);
return true;
}
};
setTitle("Test Alarm");
add(new RichTextField(" "));
add(alarm1 );
}
public void datePicker(final int alarmNumber)
{
UiApplication.getUiApplication().invokeLater(new Runnable()
{
public void run()
{
DateTimePicker datePicker = null;
datePicker = DateTimePicker.createInstance(TestClass.alarm1time, null, "HH:mm");
if(datePicker.doModal())
{
Calendar cal = datePicker.getDateTime();
TestClass.alarm1time = cal;
//Here I need the label to be refreshed, after the datePicker is Ok
}
}
});
}
}

Answer 1

I found one way in the Blackberry Development Forum...
public boolean navigationClick (int status , int time)
{
datePicker(1, this);
return true;
}
public void datePicker(final int alarmNumber, final ButtonField buttonToUpdate)
{
UiApplication.getUiApplication().invokeLater(new Runnable()
{
public void run()
{
DateTimePicker datePicker = null;
datePicker = DateTimePicker.createInstance(TestClass.alarm1time, null, "HH:mm");
if(datePicker.doModal())
{
Calendar cal = datePicker.getDateTime();
TestClass.alarm1time = cal;
buttonToUpdate.setLabel(....)
}
}
});
}
A more usual way would be to have change listener listen for Button Clicks and do similar processing in there.

Answer 2

I think, this helps you:
public class Def extends MainScreen
{
ButtonField show;
LabelField label;
String str="";
ObjectChoiceField choiceField;
public Def()
{
createGUI();
}
private void createGUI()
{
String st_ar[]={"Date Picker"};
choiceField=new ObjectChoiceField("Select Date: ", st_ar)
{
protected boolean navigationClick(int status, int time)
{
DateTimePicker datePicker = DateTimePicker.createInstance( Calendar.getInstance(), "yyyy-MM-dd", null);
datePicker.doModal();
Calendar calendar=datePicker.getDateTime();
str=String.valueOf(calendar.get(Calendar.DAY_OF_MONTH))+"-"+String.valueOf(calendar.get(Calendar.MONTH)+1)+"-"+calendar.get(Calendar.YEAR);
return true;
}
};
add(choiceField);
label=new LabelField("",Field.NON_FOCUSABLE);
add(label);
show=new ButtonField("Show");
show.setChangeListener(new FieldChangeListener()
{
public void fieldChanged(Field field, int context)
{
label.setText("Time is: "+str);
}
});
add(show);
}
}