How to display Pane with non-rectangle shape in JavaFX? - javafx

Question

I've met a problem in JavaFX.
This is what show in Jasperserver (A server), Adhoc-Model (One of a model of server).
Image: Jasperserver Adhoc Layout
Image: Inner HTML Code
As you can see, the pink area, is a type of HTML < li > Tag. It can display UI with a non-rectangle shape. Like Tetris?
However, I'am trying to do the same thing in JavaFX but failed.
I used a FlowPane as Pane A, and put some Label into Pane A. Then I used a little FlowPane as Pane B, also put some Label into Pane B. At last, I put Pane B into Pane A.
It's shown as following image.
Image: Shown in JavaFX
As you can see, I failed to display the Pane B with a non-rectangle shape. And I think it is not very easy to do that.
Can anybody help me ? Your answer will be appreciated. Thank you very much.
If anyone need my code, please tell me. I will rewrite some simple code and put on here.

Answer 1

Thanks #James_D Very Much.
I've written a custom pane which extends FlowPane, and overridden layoutChildren() function.
It works !
Following is my code:
import java.util.ArrayList;
import java.util.List;
import javafx.geometry.HPos;
import javafx.geometry.Insets;
import javafx.geometry.VPos;
import javafx.scene.Node;
import javafx.scene.control.Label;
import javafx.scene.layout.FlowPane;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.Region;
public class LayoutFlowPane extends FlowPane {
private class Child {
Node node;
double x, y, w, h;
double blft, midy;
public Child(Node node,
double x, double y, double w, double h,
double blft, double midy) {
super();
this.node = node;
this.x = x;
this.y = y;
this.w = w;
this.h = h;
this.blft = blft;
this.midy = midy;
}
}
private List<Child> children = new ArrayList<>();
private List<Double> midys = new ArrayList<>();
public LayoutFlowPane() {
super();
}
#Override protected void layoutChildren() {
super.layoutChildren();
Insets insets = getInsets();
double width = getWidth();
double height = getHeight();
double top = insets.getTop();
double left = insets.getLeft();
double bottom = insets.getBottom();
double right = insets.getRight();
double maxw = width - left - right;
double maxh = height - top - bottom;
double hgap = snapSpace(this.getHgap());
double vgap = snapSpace(this.getVgap());
storeChildren();
adjustChildren(maxw, maxh, hgap, vgap);
children.forEach(child -> {
layoutInArea(
child.node, child.x, child.y,
child.w, child.h, child.blft, getMargin(child.node),
getColumnHalignmentInternal(), getRowValignmentInternal()
);
});
}
private void storeChildren() {
children = new ArrayList<>();
for (int i = 0; i < getChildren().size(); i ++) {
Node child = getChildren().get(i);
double x = child.getLayoutX();
double y = child.getLayoutY();
double w = 0;
double h = 0;
if (child instanceof Region) {
Region region = (Region) child;
w = region.getWidth();
h = region.getHeight();
} else {
throw new UnknowTypeException("Unknow type found.");
}
double blft = child.getBaselineOffset();
double midy = (y + y + h) / 2;
Child newChild = new Child(child, x, y, w, h, blft, midy);
children.add(newChild);
}
midys = new ArrayList<>();
for (int i = 0; i < children.size(); i ++) {
Child child = children.get(i);
if (midys.isEmpty() || midys.get(midys.size()-1) != child.midy) {
midys.add(child.midy);
}
}
}
private void adjustChildren(double maxw, double maxh, double hgap, double vgap) {
for (int i = 1; i < children.size(); i ++) { // begin with 1
Child pc = children.get(i-1);
Child ch = children.get(i);
boolean bothGridPane = (pc.node instanceof GridPane) && (ch.node instanceof GridPane);
double x = pc.x + pc.w + (bothGridPane ? 0 : hgap);
double midy;
if (x + ch.w <= maxw) { // ThisLine
midy = pc.midy;
ch.x = x;
ch.y = gety(ch.y, ch.midy, midy);
ch.midy = midy;
} else { // NextLine
midy = getNextMidy(pc.midy);
ch.x = children.get(0).x;
ch.y = gety(ch.y, ch.midy, midy);
ch.midy = midy;
}
}
}
private double getNextMidy(double midy) {
for (int i = 0; i < midys.size(); i ++) {
if (i + 1 < midys.size() && midys.get(i) == midy && midys.get(i+1) != midy) {
return midys.get(i+1);
} else if (i + 1 == midys.size() && midys.get(i) == midy) {
return midys.get(i);
}
}
throw new NotFoundException("Next midy not found.");
}
private double gety(double oldy, double oldMidy, double newMidy) {
return oldy + (newMidy - oldMidy);
}
private HPos getColumnHalignmentInternal() {
HPos localPos = getColumnHalignment();
return null == localPos ? HPos.LEFT : localPos;
}
private VPos getRowValignmentInternal() {
VPos localPos = getRowValignment();
return null == localPos ? VPos.CENTER : localPos;
}
private class UnknowTypeException extends RuntimeException {
private static final long serialVersionUID = 1L;
public UnknowTypeException(String message) {
super(message);
}
}
private class NotFoundException extends RuntimeException {
private static final long serialVersionUID = 1L;
public NotFoundException(String message) {
super(message);
}
}
}