In my first blog on JavaFX I mentioned polishing the details takes a lot of time and I thought it is due to the lack of experience. As I am spending more time trying to develop a real-life desktop application, I am becoming more doubtful about this. Too often I have to spend too much time trying to make the UI behave the way I want and sometimes I just have to give up and change my mind about the desired design to avoid wasting even more time. It is hard to provide concrete examples and ask for help as my application’s UI is quite complex. But recently I could isolate a simple case that I can use to demonstrate what I am talking about.
Look at the following simple code:

import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;

var rec1: Rectangle;
var stage: Stage = Stage {
    title: "Rectangles"
    width: 200
    height: 200
    scene: Scene {
        content: [
            VBox {
                spacing: 0
                content: [
                    rec1 = Rectangle {
                        fill: Color.BLACK
                        width: bind stage.scene.width
                        height: 50
                    }
                    Rectangle {
                        fill: Color.GRAY
                        width: bind stage.scene.width
                        height: bind stage.scene.height - rec1.height
                    }
                ]
            }
        ]
    }
}

It creates a window containing two rectangles that fully cover the scene:
Rectangles screenshot
All works great at this point.
Now, let’s see what happens when I set the stroke to Color.BLACK:

...
                    Rectangle {
                        fill: Color.GRAY
                        stroke: Color.BLACK
                        width: bind stage.scene.width
                        height: bind stage.scene.height - rec1.height
                    }
...

Running this I am getting the following result:
Rectangles screenshot
As you can see, besides the fact that the rectangle now has the black border, it also jumped both horizontally and vertically and uncovered a strip of white background color. Going back and forth trying to find a workaround can be time consuming – I did not find a good way of debugging this kind of issues. Now imagine the same thing happens when the UI contains many more nested components. Trying to figure out which one causes the problem and how to tweak things to get the desired result may be endless.
Anyway, I am still not giving up! Has anyone found an efficient way of debugging and resolving this type of issues quickly?