I have a working map using Pane and Path and Label objects. I place several Path and Label objects onto the Pane. The Path objects represent countries and the Label objects their capitals. So it shows a country and in the middle a Label with a String object bound to the Label.
count.textProperty().bind(system.getNations().get(nameNoSpace).getTroopCount().asString());
When using BorderPane instead of Pane the Label objects suddenly stop showing up?
Any idea what is the reason ?
Is the BorderPane hiding the Labels ?
Thanks
You cannot add children to a BorderPane using the root.getChildren().add(node) method.
to add object to a BorderPane you need to use other methods such as
setCenter(node);
setTop(node);
setBottom(node);
setLeft(node);
setRight(node);
See the BorderPane documentation for more informations.
If you need to use thegetChildren().add() method you can insert a Pane at the center of the BorderPane and add the nations in the Pane.
Related
I'm learning basic JavaFX right now, and I don't understand this statement from the book I'm reading: "No, a node such as a text field can be added to only one pane and once. Adding a node to a pane multiple times or to different panes will cause a runtime error." I can see from the UML diagram the book provides that it is a composition, but I don't understand why (library class code implementation) that is.
For instance, why does this result in a compile error? Isn't a new text field instantiated within the pane since it's a composition?
FlowPane pane = new FlowPane();
StackPane pane2 = new StackPane();
TextField tf = new TextField();
pane.getChildren().add(tf);
pane.getChildren().add(tf);
Also, why does the following run but not show the text field placed in pane?
FlowPane pane = new FlowPane();
StackPane pane2 = new StackPane();
TextField tf = new TextField();
pane.getChildren().add(tf);
pane2.getChildren().add(tf);
primaryStage.setScene(new Scene(pane));
primaryStage.show();
This is basically a (deliberate) consequence of the way the API is designed. Each Node has a collection of properties, including a parent property (the - one and only one - parent of the node in the scene graph), along with properties such as layoutX and layoutY which are the coordinates of the node in relation to its parent. Consequently, a node can only belong to one parent, and can only be added to a parent once (as it can only have one location in the parent). Organizing things this way enables a very efficient layout process.
Another way to think of this: suppose your first code block did what you wanted; so the text field tf appeared twice in the flow pane. What result would you expect to get from tf.getBoundsInParent()? Since tf appears twice in the parent, the API would not be able to give a sensible value for this call.
There are a couple of inaccuracies in statements you make in your question:
For instance, why does this result in a compile error? Isn't a new
text field instantiated within the pane since it's a composition?
First, technically, this is aggregation, not composition; though I'm not sure understanding the difference will aid your understanding of what is happening at this point.
Second, there is no compile error here; you get an error at runtime (the pane detects that the same node has been added twice; the complier has no way to check this).
Third, parents do not instantiate copies of the nodes you add to them. If so, you wouldn't be able to change the properties of nodes that were displayed. For example, if the FlowPane in your example instantiated a new TextField when you called pane.getChildren().add(tf);, and then displayed that new text field, then if you subsequently called tf.setText("new text"), it would have no effect, as it would not be changing the text of the text field that pane was displaying.
When you call pane.getChildren().add(...) you pass a reference to the node you want to be added; it is that node that is then displayed as a child of the pane. Any other implementation would produce pretty counter-intuitive behavior.
In your second code block:
pane.getChildren().add(tf);
pane2.getChildren().add(tf);
the second call implicitly sets the parent property of tf to pane2; consequently tf is no longer a child of pane. So this code has the effect of removing tf from the first parent, pane. As far as I am aware, this side-effect is not documented, so you probably should avoid writing code like this.
Try this:
TextField tf = new TextField();
TextField tf2 = new TextField();
pane.getChildren().add(tf);
pane.getChildren().add(tf2);
The reason you cannot add the same node twice is that only one node with the same specifications and dimensions can be viewable in the gui. It would be like copying an identical blue circle onto an original blue circle. To the user it looks the same, but it takes up more memory.
I'm trying to make an application which switches between scenes back and forth however I need to load a specific AnchorPane's contents into another AnchorPane when the scene switches back. For Example:
In my FXML1, I have a hierarchy that looks like this:
AnchorPane0
----SplitPane
--------AnchorPane1
--------AnchorPane2
In FXML2 the hierarchy is just this:
AnchorPane0
So I load FXML1, then I have a button that switches scenes loading FXML2.AnchorPane0 into FXML1.AnchorPane2. I have a back button in FXML2.AnchorPane0 that needs to load the original scene of FXML1.AnchorPane2 into FXML1.AnchorPane2. Right now my back button loads all 4 containers of FXML1 into FXML1.AnchorPane2. So my questions is, how do I load a specific container's contents preferably without making FXML1.AnchorPane2 its own FXML? Do I need to write a get method for the FXML1.AnchorPane2 to access its contents or is there a way to return an AnchorPane with all of its contents in place already?
I found the solution as shown below:
AnchorPane loader = FXMLLoader.load(getClass().getResource("myFXML.fxml"));
SplitPane spane = (SplitPane) loader.getChildren().get(0);
AnchorPane pane = (AnchorPane) spane.getItems().get(1);
foregroundAnchorPane.getChildren().setAll(pane);
I am trying to create a "custom widget" (extends HBox) which renders 3D graphics.
The problem is that all the examples I see for setting the camera, show how to do it on the main "scene", which belongs to the main window.
I don't want any relation to the main Window, I want it to be an independent widget.
Is it anyway possible to do that?
I'll be glad if you can share some code example, as I feel pretty lost with it...
I am not quite sure if I understood you correctly, but if you want the camera to be transformable, you can insert it into the Scene Graph where ever you want. You can add it to a group node like this:
Group someGroup = new Group();
PerspectiveCamera camera = new PerspectiveCamera();
someGroup.getChildren().add(camera);
Scene s = new Scene(someGroup);
s.setCamera(camera);
When you now move the Group node the camera moves as well. You can add the camera to any Group node you want, but I am not sure what happens when you put it into a Group node that uses LayoutManagement like HBox.
The important thing is you always have to add the camera to the Scene that it is in.
I have an FXML file that I'm using to allow user input when requested. Right now I just put it in a new stage and do Stage.show(). I would like to not have it appear in a new window and behave more like a ContextMenu.
Looking at ContextMenu class it doesn't appear that I can set the content based off an FXML file. Is there a way to do this either with ContextMenu or Popup or some other class I am unaware of?
Although that library is quite nice, I wanted something simple that didn't require 3rd party downloads. I came up with this:
Popup popup = new Popup();
CustomController controller = new CustomController();
FXMLLoader loader = new FXMLLoader(getClass().getResource(fxmlfile));
loader.setController(controller);
popup.getContent().add((Parent)loader.load());
The problem was I didn't realize that a Parent could be considered a Node for the method Popup#getContent#add
ControlsFX has a PopOver control you might like. That PopOver can use any Node for its content, so you can simply create a popover, load a node from FXML and set the content of the popover to that node.
I'm using eclipse with scene builder.
I have build a new fxml document with:
- 2 labels
- one table view
I want to add several of this element into other window (i.e. add several of this element into tilePane).
How can I do it ?
When I'm trying to do this:
Pane pane1 = (Pane)loader.load();
Pane pane2 = (Pane)loader.load();
tilePaneRootLayout.getChildren().add(pane1);
tilePaneRootLayout.getChildren().add(pane2);
I'm getting empty window.
1. why this happen ?
2. how can I solve it ?
Thanks
Create a new loader for each new Pane