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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:
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 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
/**
* 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.
* <p>
* 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:
* <pre>{@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);
* }</pre>
* <p>
* 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.</p>
*
* <p>
* Pane resizes each managed child regardless of the child's visible property value;
* unmanaged children are ignored for all layout calculations.</p>
*
* <h3>Resizable Range</h3>
*
* <p>
* 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:
* </p>
*
* <table border="1">
* <caption>Pane Resize Table</caption>
* <tr><td></td><th scope="col">width</th><th scope="col">height</th></tr>
* <tr><th scope="row">minimum</th>
* <td>left plus right insets.</td>
* <td>top plus bottom insets.</td></tr>
* <tr><th scope="row">preferred</th>
* <td>width required to encompass each child at its current x location and preferred width.</td>
* <td>height required to encompass each child at its current y location and preferred height.</td></tr>
* <tr><th scope="row">maximum</th>
* <td>Double.MAX_VALUE</td><td>Double.MAX_VALUE</td></tr>
* </table>
* <p>
* 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.
* <p>
* 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:
* <pre><code>
* <b>pane.setPrefSize(500,400);</b>
* </code></pre>
* Applications may restore the computed values by setting these properties back
* to Region.USE_COMPUTED_SIZE.
* <p>
* 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.</p>
*
* @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.
/**
* Creates a Pane layout.
*/
public Pane() {
super();
}
Creates a Pane layout.
Params: - children – The initial set of children for this pane.
Since: JavaFX 8.0
/**
* 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);
}
Returns: modifiable list of children.
/**
*
* @return modifiable list of children.
*/
@Override public ObservableList<Node> getChildren() {
return super.getChildren();
}
}