javafx.scene.layout.Pane Maven / Gradle / Ivy
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* accompanied this code).
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package javafx.scene.layout;
import com.sun.javafx.scene.layout.PaneHelper;
import javafx.beans.DefaultProperty;
import javafx.collections.ObservableList;
import javafx.scene.Node;
/**
* Base class for layout panes which need to expose the children list as public
* so that users of the subclass can freely add/remove children.
*
* This class may be used directly in cases where absolute positioning of children
* is required since it does not perform layout beyond resizing resizable children
* to their preferred sizes. It is the application's responsibility to position the
* children since the pane leaves the positions alone during layout.
* For example:
*
{@code
* Pane canvas = new Pane();
* canvas.setStyle("-fx-background-color: black;");
* canvas.setPrefSize(200,200);
* Circle circle = new Circle(50,Color.BLUE);
* circle.relocate(20, 20);
* Rectangle rectangle = new Rectangle(100,100,Color.RED);
* rectangle.relocate(70,70);
* canvas.getChildren().addAll(circle,rectangle);
* }
*
* Note: if an application needs children to be kept aligned within a parent (centered,
* positioned at top-left, etc), it should use a {@link javafx.scene.layout.StackPane StackPane}
* instead.
*
*
* Pane resizes each managed child regardless of the child's visible property value;
* unmanaged children are ignored for all layout calculations.
*
* Resizable Range
*
*
* A pane's parent will resize the pane within the pane's resizable range
* during layout. By default the pane computes this range based on its content
* as outlined in the table below:
*
*
*
* Pane Resize Table
* width height minimum
* left plus right insets.
* top plus bottom insets. preferred
* width required to encompass each child at its current x location and preferred width.
* height required to encompass each child at its current y location and preferred height. maximum
* Double.MAX_VALUE Double.MAX_VALUE
*
* A pane'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.
*
* Pane provides properties for setting the size range directly. These
* properties default to the sentinel value Region.USE_COMPUTED_SIZE, however the
* application may set them to other values as needed:
*
* pane.setPrefSize(500,400);
*
* Applications may restore the computed values by setting these properties back
* to Region.USE_COMPUTED_SIZE.
*
* Pane does not clip its content by default, so it is possible that children's
* bounds may extend outside its own bounds, either if children are positioned
* at negative coordinates or the pane is resized smaller than its preferred size.
*
* @since JavaFX 2.0
*/
@DefaultProperty("children")
public class Pane extends Region {
static {
PaneHelper.setPaneAccessor(new PaneHelper.PaneAccessor() {
});
}
static void setConstraint(Node node, Object key, Object value) {
if (value == null) {
node.getProperties().remove(key);
} else {
node.getProperties().put(key, value);
}
if (node.getParent() != null) {
node.getParent().requestLayout();
}
}
static Object getConstraint(Node node, Object key) {
if (node.hasProperties()) {
Object value = node.getProperties().get(key);
if (value != null) {
return value;
}
}
return null;
}
{
// To initialize the class helper at the begining each constructor of this class
PaneHelper.initHelper(this);
}
/**
* Creates a Pane layout.
*/
public Pane() {
super();
}
/**
* Creates a Pane layout.
* @param children The initial set of children for this pane.
* @since JavaFX 8.0
*/
public Pane(Node... children) {
super();
getChildren().addAll(children);
}
/**
*
* @return modifiable list of children.
*/
@Override public ObservableList getChildren() {
return super.getChildren();
}
}