Stage should respect minimum size of its content

Question

Hi,
I wonder if there was a standardized approach to make the Stage inherits its minimum size from its content.
I tried to bind the Stage's mimimumWidthProperty to StackPane equivalent but without any success.
The only way I found was to 'force' the size by explicitly call stage.setMinWidth(), but this not really dynamic.
For information, the preferred size works fine and is well managed by the Stage.
Thanks.
If the following example, the Stage does not respect the minimum size set on the StackPane:
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;
public class TestMinSize extends Application {
    @Override
    public void start(Stage primaryStage) {
        Button btn = new Button();
        btn.setText("Say 'Hello World'");
        StackPane root = new StackPane();
        // set minimum size
        root.setMinWidth(200);
        root.setMinHeight(200);
        root.getChildren().add(btn);
        Scene scene = new Scene(root, 300, 250);
        primaryStage.setTitle("Hello World!");
        primaryStage.setScene(scene);
        primaryStage.show();
}

Answer 1

The only thing that springs to mind is binding the properties to substract the decoration size of the stage.
But this wouldn't take into account if a child node of your root node has a minWidth/Height larger than the root's.
And generally this only works if root has a minSizeProperty, but Scene.getRoot() is a Parent.
primaryStage.minHeightProperty().bind(primaryStage.heightProperty().subtract(scene.heightProperty()).add(root.minHeightProperty()));
primaryStage.minWidthProperty().bind(primaryStage.widthProperty().subtract(scene.widthProperty()).add(root.minWidthProperty()));Or slightly more general:
public static void respectMinimumSize(Stage stage) {
     Scene scene = stage.getScene();
     if (scene.getRoot() instanceof Region) {
          Region root = (Region) scene.getRoot();
          stage.minHeightProperty().bind(Bindings.max(0, stage.heightProperty().subtract(scene.heightProperty()).add(root.minHeightProperty())));
          stage.minWidthProperty().bind(Bindings.max(0, stage.widthProperty().subtract(scene.widthProperty()).add(root.minWidthProperty())));
}Edited by: Dejay on Mar 10, 2013 5:56 PM
Edited by: Dejay on Mar 10, 2013 5:57 PM