Help test the behavior of a multi-screen setup with both Mac and Windows

[John Hendrikx]

On Windows it is not restricted AFAIK, moving a screen anywhere is
allowed, and one can also drag windows beyond those limits.  When a
monitor is added/removed Windows may however decide to reshuffle all
your Windows (or randomly if a monitor is slow to respond when waking
from sleep) to ensure they're all visible.

I think Windows just treats the screen space as infinite with the
monitors being views into it; overlaps and gaps are allowed, although
you need some tricks to get your screens setup that way.

Not sure what you find odd about the Windows behaviour?

--John

On 09/04/2025 13:57, Thiago Milczarek Sayão wrote:
> Thanks John!
>
> I did not calculate the center, I just wanted to know the behaviour of
> setX() outside bounds and within
> bounds of the last screen.
>
> The GNOME window manager on Linux restricts programmatic movement of
> windows to prevent them 
> from being moved outside screen boundaries. However, it allows users
> to drag windows beyond these limits.
> I find it odd that the maximum movement is restricted to the bounds of
> the first screen, while it would be more
> intuitive for it to be based on the last screen.
>
> The Windows behaviour also seems odd.
>
> -- Thiago
>
> Em qua., 9 de abr. de 2025 às 08:28, John Hendrikx
> <john.hendrikx at gmail.com> escreveu:
>
>     Small addition; the 3520 button moved the top left of the Window
>     to the middle of the right screen, but the window as a whole was
>     not centered.
>
>     --John
>
>     On 09/04/2025 13:22, John Hendrikx wrote:
>>
>>     Hi Thiago,
>>
>>     I ran this on Windows.  My monitor setup is:
>>
>>     Left: 3840x2160 (150%) -- top left coordinate (-2560, 0) (-2560
>>     because of scaling)
>>     Middle: 3840x2160 (150%) -- this one has a top left coordinate of
>>     (0, 0)
>>     Right: 1920x1200 (100%) -- this one has a top left coordinate of
>>     (2560, 0)
>>
>>     When started, the program appeared perfectly centered on the
>>     middle screen.
>>
>>     Your program showed buttons: 4480 and 3520
>>
>>     The 4480 button moved the Window far too the right, off screen
>>     and I had to stop the program
>>
>>     The 3520 button moved the Window to the Right monitor, but it was
>>     not centered nicely.
>>
>>     I added a `peek(System.out::println)` on the screens stream. 
>>     These are my screens:
>>
>>     Rectangle2D [minX=0.0, minY=0.0, maxX=2560.0, maxY=1440.0,
>>     width=2560.0, height=1440.0]
>>
>>     Rectangle2D [minX=2560.0, minY=-194.0, maxX=4480.0, maxY=1006.0,
>>     width=1920.0, height=1200.0]
>>
>>     Rectangle2D [minX=-2560.0, minY=6.0, maxX=0.0, maxY=1446.0,
>>     width=2560.0, height=1440.0]
>>
>>     --John
>>
>>     On 09/04/2025 12:55, Thiago Milczarek Sayão wrote:
>>>     Hi,
>>>
>>>     Could anyone with a multi-screen setup on Mac and/or Windows
>>>     please share the results of the two buttons on this sample app?
>>>     Your feedback would be greatly appreciated!
>>>
>>>     On Ubuntu 24.04 the first button moves the Stage to the end of
>>>     the first screen (bit weird). 
>>>     The second work as expected, it gets moved to the start of the
>>>     center of the last screen.
>>>
>>>     Thanks!
>>>
>>>     import javafx.application.Application;
>>>     import javafx.geometry.Pos;
>>>     import javafx.geometry.Rectangle2D;
>>>     import javafx.scene.control.Button;
>>>     import javafx.scene.layout.VBox;
>>>     import javafx.stage.Screen;
>>>     import javafx.stage.StageStyle;
>>>     import javafx.application.Platform;
>>>     import javafx.scene.Scene;
>>>     import javafx.scene.layout.StackPane;
>>>     import javafx.scene.paint.Color;
>>>     import javafx.stage.Stage;
>>>
>>>     import java.util.Comparator;
>>>
>>>     public class TestScreenBounds extends Application {
>>>
>>>         @Override
>>>         public void start(Stage stage) {
>>>             stage.setTitle("Move Outside Bounds");
>>>             Rectangle2D bounds = Screen.getScreens().stream()
>>>                     .map(Screen::getBounds)
>>>                     .sorted(Comparator.comparingDouble(Rectangle2D::getMaxX).reversed())
>>>                     .findFirst()
>>>                     .orElseThrow();
>>>
>>>             Button btn = new Button("Move To " + bounds.getMaxX());
>>>             btn.setOnAction(event -> stage.setX(bounds.getMaxX()));
>>>
>>>             double middleLastScreen = bounds.getMinX() + bounds.getWidth() / 2;
>>>
>>>             Button btn2 = new Button("Move To " + middleLastScreen);
>>>             btn2.setOnAction(event -> stage.setX(middleLastScreen));
>>>
>>>             VBox root = new VBox(btn, btn2);
>>>             root.setFillWidth(true);
>>>             root.setAlignment(Pos.CENTER);
>>>             Scene scene = new Scene(root, 300, 300);
>>>             stage.setScene(scene);
>>>             stage.show();
>>>         }
>>>
>>>         public static void main(String[] args) {
>>>             launch(TestScreenBounds.class, args);
>>>         }
>>>     }
>>>
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