Module javafx.graphics
Package javafx.scene.layout

Class StackPane

java.lang.Object
javafx.scene.Node
javafx.scene.Parent
javafx.scene.layout.Region
javafx.scene.layout.Pane
javafx.scene.layout.StackPane
All Implemented Interfaces:
Styleable, EventTarget
Direct Known Subclasses:
TableHeaderRow
public class StackPane extends Pane
StackPane lays out its children in a back-to-front stack.

The z-order of the children is defined by the order of the children list with the 0th child being the bottom and last child on top. If a border and/or padding have been set, the children will be laid out within those insets.

The stackpane will attempt to resize each child to fill its content area. If the child could not be sized to fill the stackpane (either because it was not resizable or its max size prevented it) then it will be aligned within the area using the alignment property, which defaults to Pos.CENTER.

StackPane example: 


     StackPane stack = new StackPane();
     stack.getChildren().addAll(new Rectangle(100,100,Color.BLUE), new Label("Go!"));

StackPane lays out each managed child regardless of the child's visible property value; unmanaged children are ignored.

StackPane may be styled with backgrounds and borders using CSS. See Region for details.

Resizable Range

A stackpane's parent will resize the stackpane within the stackpane's resizable range during layout. By default the stackpane computes this range based on its content as outlined in the table below.

StackPane Resize Table
widthheight
minimum left/right insets plus the largest of the children's min widths. top/bottom insets plus the largest of the children's min heights.
preferred left/right insets plus the largest of the children's pref widths. top/bottom insets plus the largest of the children's pref heights.
maximum Double.MAX_VALUEDouble.MAX_VALUE

A stackpane's unbounded maximum width and height are an indication to the parent that it may be resized beyond its preferred size to fill whatever space is assigned to it.

StackPane provides properties for setting the size range directly. These properties default to the sentinel value USE_COMPUTED_SIZE, however the application may set them to other values as needed: 

     // ensure stackpane is never resized beyond it's preferred size
     stackpane.setMaxSize(Region.USE_PREF_SIZE, Region.USE_PREF_SIZE);
Applications may restore the computed values by setting these properties back to USE_COMPUTED_SIZE.

StackPane does not clip its content by default, so it is possible that children's bounds may extend outside its own bounds if a child's min size prevents it from being fit within the stackpane.

Optional Layout Constraints

An application may set constraints on individual children to customize StackPane's layout. For each constraint, StackPane provides a static method for setting it on the child.

StackPane Constraint Table
ConstraintTypeDescription
alignmentjavafx.geometry.PosThe alignment of the child within the stackpane.
marginjavafx.geometry.InsetsMargin space around the outside of the child.

Examples: 

     // Align the title Label at the bottom-center of the stackpane
     Label title = new Label();
     StackPane.setAlignment(title, Pos.BOTTOM_CENTER);
     stackpane.getChildren.addAll(new ImageView(...), title);

     // Create an 8 pixel margin around a listview in the stackpane
     ListView list = new ListView();
     StackPane.setMargin(list, new Insets(8,8,8,8);
     stackpane.getChildren().add(list);
Since:
JavaFX 2.0