Hi Rafal,
Couple of things: the code that checks the context for the event dispatch thread also
allows "main" as an acceptable thread because things can be done in "main"
BEFORE starting the Event Dispatch Thread (EDT) (not after, though), so that doesn't quite explain
it.
But, I think you have hit on the real problem: "setHeight" is meant to be called from
within Pivot with the final calculated height once all the dust settles. For a Frame (as most containers) it
will try to size itself to an appropriate value for its children and then call "setHeight" with the
final value. Setting a "preferred" value will override (at least usually) the size calculated from
the children and use that preferred value for the container size.
Also, the "startup" method is probably the right place to do UI size calculations
because you have the Display which can get you to the screen size, etc. (rather than in the
"main" method which doesn't have that information directly).
So, I'm sorry I didn't think about these things in my first reply. The
"best" code, then, would be something like this:
public void startup(Display display, Map<String, String> properties)
throws Exception
{
Frame frame = new Frame();
frame.setPreferredHeight(100);
frame.open(display);
}
Roger Whitcomb
-----Original Message-----
From: Rafał Gierusz [mailto:[email protected]]
Sent: Tuesday, February 14, 2012 11:30 AM
To: [email protected]
Subject: RE: RE: 2.0.1 Resizing problem
Hi Roger,
I tried a lot of "tricks" before I wrote about my problem, I'll try to
share my result here. Let's assume that the base for our discussion is
the code I put in my first email. When "frame.setHeight(100)" will be
replaced with:
new Thread() {
public void run() {
frame.setPreferredHeight(100);
}
}.start();
the exception will the thrown: Exception in thread "Thread-4"
java.lang.IllegalStateException: this method can only be called from the
AWT event dispatch thread, and not from "Thread-4". Which makes me think
that I used the right thread in my "base" code from first email. I
noticed also that a method assertEventDispatchThread(Component
component) from Component is used to validate if the proper thread is
used for executing request of change.
But anyway, I went further and tried also something like this:
DesktopApplicationContext.queueCallback(new Runnable() {
public void run() {
frame.setHeight(100);
}
});
and in that case it had no result, no result at all. But... when I
change setHeight to setPreferred, like in the following example:
DesktopApplicationContext.queueCallback(new Runnable() {
public void run() {
frame.setPreferredHeight(100);
}
});
it seems to be working correctly. But I still don't know why setHeight
doesn't work.
Any ideas about that?
Regards,
Rafal
---
From "Roger L. Whitcomb"<[email protected]>
Subject RE: 2.0.1 Resizing problem
Date Tue, 14 Feb 2012 17:15:30 GMT
Hi Rafał,
Without actually trying to run your code, I think the problem is that
you shouldn't be modifying
any UI elements in a non-UI thread.
Once you call "DesktopApplicationContext.main()" it starts another
thread to run the basic
event loop of your GUI application. This calls "startup()" as one of the first
things it
does. But, since your "main" method and the "startup" method are now in two
different threads,
it is problematic which one runs first, and it is basically illegal to modify
any UI components
in a different thread than the UI thread (for a number of reasons). So, your call to
"frame.setHeight()"
in the main thread is violating this rule. If you put the "frame.setHeight()"
right after
"frame = new Frame()" and before the "frame.open" then everything should be
fine. Something
like this:
public void startup(Display display, Map<String, String> properties)
throws Exception
{
Frame frame = new Frame();
frame.setHeight(100);
frame.open(display);
}
public static void main(String[] args) throws Exception {
DesktopApplicationContext.main(BasicTest.class, new String[0]);
// This is a non-UI thread now, so no changes to "frame" are going to
work if done
here
}
Let us know if you have further problems.
~Roger Whitcomb
-----Original Message-----
From: Rafał Gierusz [mailto:[email protected]]
Sent: Tuesday, February 14, 2012 8:23 AM
To: [email protected]
Subject: 2.0.1 Resizing problem
Hi,
I have problem with resizing a Frame window, please take a look on the
code below (I tried to make it as simple as possible to show my
concerns, it's not pretty).
public class BasicTest extends Application.Adapter {
static Frame frame;
public void startup(Display display, Map<String, String> properties)
throws Exception {
frame = new Frame();
frame.open(display);
}
public static void main(String[] args) throws Exception {
DesktopApplicationContext.main(BasicTest.class, new String[0]);
Thread.sleep(2000); //to have a short while to take a look on the
displayed window
frame.setHeight(100);
}
}
When application starts we can see a main window and a very small
internal window (Frame) in it. After two seconds internal frame changes
its height to 100, I do it using frame.setHeight(100). But when you move
mouse over the main window Frame changes back it's height to the one
before we changed it to 100. Can you tell me what's wrong here?
What's more interesting, when I use setPreferredHeight instead the
Frame's height is not changed until mouse is moved, which is of course
not good too.
Regards,
Rafal
