Dividing vertically a pane in sections of the same size

Question

I am trying to devide a pane (a HBox pane) in three parts with exactly the same width, that together uses all the available width of the parent pane where it is located.
I tried with the following code and it looks more or less fine:
HBox buttonsPane = new HBox();
HBox addDriverPaneHBox = new HBox();
addDriverPaneHBox.setAlignment(Pos.CENTER);
HBox.setHgrow(addDriverPaneHBox, Priority.SOMETIMES);
addDriverPaneHBox.getChildren().add(addDriverPane);
HBox startPrologEnginePaneHBox = new HBox();
startPrologEnginePaneHBox.setAlignment(Pos.CENTER);
HBox.setHgrow(startPrologEnginePaneHBox, Priority.SOMETIMES);
startPrologEnginePaneHBox.getChildren().add(startPrologEnginePane);
HBox shutdownPrologEnginePaneHBox = new HBox();
shutdownPrologEnginePaneHBox.setAlignment(Pos.CENTER);
HBox.setHgrow(shutdownPrologEnginePaneHBox, Priority.SOMETIMES);
shutdownPrologEnginePaneHBox.getChildren().add(shutdownPrologEnginePane);
buttonsPane.getChildren().addAll(addDriverPaneHBox, startPrologEnginePaneHBox, shutdownPrologEnginePaneHBox);However, the code above does not enforce that the three divisions have exactly the same width. I tried changing the type of buttonsPane to TilePane but it did not help (with the TilePane the children had the same size but they did not use all the width available in the parent pane). Any alternative ?

Answer 1

I haven't tried this, but maybe look at putting your three pieces into a tile pane, and the tile pane into the HBox. Then bind the tile pane's prefTileWidthProperty to one third of the available space.
Something like:
HBox buttonsPane = new HBox();
TilePane tilePane = new TilePane();
tilePane.prefTileWidthProperty.bind(
  buttonsPane.widthProperty()
      .subtract(buttonsPane.spacingProperty().multiply(2))
      .divide(3)
tilePane.getChildren().addAll(addDriverPaneHBox, startPrologEnginePaneHBox, shutdownPrologEnginePaneHBox);
buttonsPane.getChildren().add(tilePane);Depending on the context this is in, you may need to force the buttonsPane to take up all the width it can, or you may be able to add the tile pane directly to the buttonPane's current parent, and bind the tilePrefWidth to some property of that instead.