Let's assume, for simplicity's sake, I have an FXML with a SplitPane. On one side I have a Button; the other has an empty AnchorPane (for now).
The button simply places a pane on the other side of the SplitPane from another FXML file. The newly added pane contains a Button and a Label. Both FXMLs have the same controller for two reasons: 1. The Added Pane FXML is not used elsewhere, 2. The Added Pane FXML has so little functions that it's not really worth it to have a separate controller for it.
Pressing the button on the newly added pane sets the text in its label to "Hello World".
Split Pane
<SplitPane fx:controller="myController".... >
<items>
<VBox .... >
<Button fx:id="mainButton" onAction="#handleFirstButton".... />
</VBox>
<AnchorPane fx:id="secondPane" ....>
</items>
</SplitPane>
Added Pane
<VBox fx:controller="myController" ....>
<Button fx:id="btn" onAction="#changeText" ... />
<Label fx:id="lbl" .... />
</VBox>
Controller Class
// Regular stuff here
#FXML
AnchorPane secondPane;
#FXML
Button mainButton;
#FXML
Button btn;
#FXML
Label lbl;
public void initialize(URL arg0, ResourceBundle arg1) {
}
private void loadSecondPane {
FXMLLoader loader = FXMLLoader.load(getClass().getResource("AddedPane.fxml"));
VBox box = loader.load();
secondPane.setTopAnchor(box);
}
#FXML
private void handleFirstButton(ActionEvent event) {
loadSecondPane();
}
#FXML
private void changeText(ActionEvent event) {
lbl.setText("Hello World");
}
The problem is, when the Added Pane is loaded, its components will NOT be defined in the controller, and trying to perform any method on them will produce a NullPointerException.
Is there a way around this or is having a separate controller mandatory in this case? And assuming I have 2+ buttons on the first side of the pane, and each button produces a different pane on the other side, does the solution remain the same?
NOTE: I'm fairly new with javafx, so excuse any mistypes.
Related
I have a pane with a label, a text field and a combo box inside a VBox in fxml file. Let´s call it tempPane.
In the same stage I have a button.
Once the button is pressed I need to add to the VBox a pane exactly the same as tempPane. This is, adding dynamically a pane to the VBOX.
I am able to add individual controls such as buttons or labels or text fields to the VBox, but I can´t obtain the same results when trying to add this new pane.
Part of the controller code:
#FXML
private Pane tempPane;
#FXML
private Button btnAddNewPane;;
#FXML
private VBox vBox;
#FXML
void addNewPane(ActionEvent event) {
...
Pane newPane = new Pane();
newPane = tempPane;
// New ID is set to the newPane, this String (NewID) should be
//different each time button is pressed
newPane.setId(newID);
vBox.getChildren().add(newPane);
...
}
And the error I´m getting is:
Exception in thread "JavaFX Application Thread" java.lang.IllegalArgumentException: Children: duplicate children added: parent = VBox[id=filterBox]
at javafx.graphics/javafx.scene.Parent$3.onProposedChange(Parent.java:580)
at javafx.base/com.sun.javafx.collections.VetoableListDecorator.add(VetoableListDecorator.java:206)
at com.sener.dbgui.controller.SearchController$1.run(SearchController.java:53)
at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$9(PlatformImpl.java:418)
at java.base/java.security.AccessController.doPrivileged(Native Method)
at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$10(PlatformImpl.java:417)
at javafx.graphics/com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:96)
at javafx.graphics/com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at javafx.graphics/com.sun.glass.ui.win.WinApplication.lambda$runLoop$3(WinApplication.java:175)
at java.base/java.lang.Thread.run(Thread.java:844)
So, why am I getting this duplicate children error? I´m changing the newPane ID before adding it to the VBox.
Pane newPane = new Pane();
newPane = tempPane;
...
vBox.getChildren().add(newPane);
This code does create a new Pane (first line) but immediately drops the new instance by overwriting it with the old one (second line).
The error happens since the contract of Node does not allow it to be placed twice in a scene and you're adding the same Pane that is already a child of vBox again. Modifying the id property does not change that fact.
You need to create a new copy of the subscene rooted at tempPane if this is supposed to work.
You could create a custom Pane for this scene:
subFXML.fxml
<fx:root xmlns:fx="http://javafx.com/fxml" type="javafx.scene.layout.Pane">
<!-- content of tempPane from old fxml goes here -->
...
<Button fx:id="btnAddNewPane" />
...
</fx:root>
public class MyPane extends Pane {
public MyPane() {
FXMLLoader loader = getClass().getResource("subFXML.fxml");
loader.setRoot(this);
loader.setController(this);
try {
fxmlLoader.load();
} catch (IOException exception) {
throw new RuntimeException(exception);
}
}
#FXML
private Button btnAddNewPane;
public void setOnAction(EventHandler<ActionEvent> handler) {
btnAddNewPane.setOnAction(handler);
}
public EventHandler<ActionEvent> getOnAction() {
return btnAddNewPane.getOnAction();
}
}
old fxml
Be sure to import MyPane.
...
<VBox fx:id="vBox">
<children>
<!-- replace tempPane with MyPane -->
<MyPane onAction="#addNewPane"/>
</children>
</VBox>
...
old controller
#FXML
private VBox vBox;
#FXML
void addNewPane(ActionEvent event) {
...
MyPane newPane = new MyPane();
newPane.setId(newID); // Don't know why setting the CSS id is necessary here
newPane.setOnAction(this::addNewPane); // set onAction property
vBox.getChildren().add(newPane);
...
}
It is written in your comments already why you are getting duplicate ID.
// New ID is set to the newPane, this String (NewID) should be
//different each time button is pressed
You are passing the same string as a parameter.
newPane.setId("NewID");
try using a dynamically generated and unique id for each pane.
String newId; //generate the id by user input or internally
newPane.setId(newId);
Can I change a Node's parent to another parent in FXML?
Suppose a parent named stackcon with a child node.
I now want to move this child node to different parent, e.g., named stackmain.
Is this possible? If yes, please give me a link or a example code.
This is just one of many ways how to do this.
MainView.fxml, just a simple view containing a button, and on button click the label should be moved from right to left and vice-versa (see the onMousePressed declaration):
<fx:root type="BorderPane" xmlns="http://javafx.com/javafx/8.0.111" xmlns:fx="http://javafx.com/fxml/1">
<left>
<VBox fx:id="lefty">
<Label fx:id="switchy" text="Switching text"></Label>
</VBox>
</left>
<center>
<Button fx:id="switchBtn" text="Switch" onMousePressed="#switchButtonPressed"></Button>
</center>
<right>
<VBox fx:id="righty">
</VBox>
</right>
</fx:root>
The controller MainView.java with its switchButtonPressed event handler:
public class MainView extends BorderPane {
#FXML private VBox lefty;
#FXML private VBox righty;
#FXML private Label switchy;
public MainView() {
URL fxmlFile = MainView.class.getResource("MainView.fxml");
FXMLLoader fxmlLoader = new FXMLLoader(fxmlFile);
fxmlLoader.setRoot(this);
fxmlLoader.setController(this);
try {
fxmlLoader.load();
} catch (IOException e) {
e.printStackTrace();
}
}
public void switchButtonPressed(MouseEvent mouseEvent) {
if(lefty.getChildren().contains(switchy)) {
lefty.getChildren().remove(switchy);
righty.getChildren().add(switchy);
} else {
righty.getChildren().remove(switchy);
lefty.getChildren().add(switchy);
}
}
}
You see, I just check on button click if the label is on the left side. If so, remove it on the left side and add it on the right side.
Analogous, if it is on the right side, remove it there and add it on the left side.
it may vary depending on type of the pane of stackmain & stackcon , i'm assuming that you use AnchorPane
but it is something like this
Node childNode = stackcon.getChildren().get(indexOfChild);
stackcon.getChildren().remove(indexOfChild);
stackmain.getChildren().add(childNode);
I'm working on a project that requires a "tabled" representation of VBoxes. My hierarchical layout of the application is GridPane -> VBox (in one of the Cells) -> VBoxes (that display different datasets on top of each other) -> Data. I have two Scenes.
Data is displayed on Scene 1. The user can add data through a form and by clicking a button on Scene 2. Then, the added data should be displayed below the existing data as a VBox within the parent-VBox on Scene 1 again.
Here is the code that will make it clear:
My Scene 1 .fxml file looks the following (Simplified):
<GridPane fx:id="grid" fx:controller="application.Controller">
[here: ColumnConstraints]
<children>
<VBox fx:id="parentBox" GridPane.columnIndex="0" GridPane.rowIndex="1"/>
<Button fx:id="goToScene2" text="+" onAction="#goToScene2"/>
</children>
</GridPane>
Scene 2 just has a button and a TextField:
<GridPane fx:id="grid" fx:controller="application.AddDataController">
[here: ColumnConstraints]
<children>
<Button fx:id="addData" text="add" onAction="#bAddData"/>
<TextField fx:id="data"/>
</children>
</GridPane>
My Scene 1 controller (controller) looks like this:
public class Controller implements Initializable {
#FXML Button goToScene2;
#FXML VBox parentBox;
#Override
public void initialize(URL location, ResourceBundle resources) {
}
public void addData(String s) {
Label lbl = new Label(s);
VBox dataBox = new VBox();
dataBox.setPadding(new Insets(15, 5, 15, 5));
dataBox.setSpacing(5);
dataBox.setMaxHeight(80);
dataBox.getChildren().add(lbl);
parentBox.getChildren().add(dataBox);
}
}
This is designed as it is because the dataBox contains more elements than the label, but that doesn't seem relevant to me in this context.
My Scene 2 controller (addDataController) looks like this:
#FXML Button addData;
#FXML TextField data;
#FXML protected void bAddData(){
String content = data.getText();
FXMLLoader fxmlLoader = new FXMLLoader();
Pane p = fxmlLoader.load(getClass().getResource("scn1.fxml").openStream());
Controller cont = (Controller) fxmlLoader.getController();
cont.addData(content);
}
So, when one clicks on the Add-Data-Button in Scene 2, the triggered method passes the entered data to the Controller of Scene 1. This is because the new data should be displayed in Scene 1 now.
I feel like the logic does not work (edited here), because when I ask for
System.out.println(parentBox.getChildren().size();
before and after the data was added, it always has one single Child, even though it should have one more...
If I artificially fill a String-Array and move everything from addData to(String s) to Initialize(...), it does work and the data shows up as VBoxes in the parent-VBox.
I didn't post the main class, because loading Controllers and Scene change is not an issue.
Thank you all very very much for your help! :)
Just to provide more detailed information, together with an idea, that I don't know how to implement.
This is my main class:
#Override
public void start(Stage primaryStage) {
currentStage = primaryStage;
Parent root = FXMLLoader.load(getClass().getResource("Scene1.fxml"));
scene1 = new Scene(root);
}
Could I load the controller at this point and make a getter that passes the Controller? So I'd only have one single instance of it throughout the program.
I tried inserting:
FXMLLoader fxmlLoader = new FXMLLoader();
fxmlLoader.load(getClass().getResource("Scene1.fxml").openStream());
Controller controller = (Controller) fxmlLoader.getController();
after the
Parent root ...
line. But that's loading the .xml file twice. How can I nicely connect both parts?
Thanks so much for you patience!
EDIT:::::::::
The following code worked for me:
#Override
public void start(Stage primaryStage) {
currentStage = primaryStage;
FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("Scene1.fxml"));
Parent root =(Parent) fxmlLoader.load();
controller = (Controller) fxmlLoader.getController();
}
Now, I can ask the main class for controller and it always passes that single instance.
Thank you for pointing me to the right direction! :)
I am trying to call an fxml (test.fxml) into another fxml (main.fxml) in center of body pane. I am actually doing this in the controller class of main.fxml. No matter how many different ways I try, I am just not able to set the center element at all.
Requirement is, I need to display different fxml files on right click of tree structure in main fxml file.
but when I call this method, I get the exception 'location is required'. Is there something I need to do? Please help.
main.fxml
#FXML
TreeView<String> mainTree;
#FXML
BorderPane rootLayout;
#FXML
AnchorPane dynamicContent;
ContextMenu cntxtMenu;
//Method where i am trying to set main.fxml center body
public void showAttributeScreen(){
FXMLLoader loader = new FXMLLoader(scriptbuilder.controller.TestController.class.getResource("view/test.fxml"));
AnchorPane pane = new AnchorPane();
try{
pane = (AnchorPane) loader.load();
rootLayout.setCenter(pane);
}
catch(Exception e){
}
}
test.fxml
<AnchorPane id="AnchorPane" prefHeight="400.0" prefWidth="600.0" xmlns:fx="http://javafx.com/fxml/1" fx:controller="scriptbuilder.controller.TestController">
<Label alignment="BASELINE_CENTER" text="Hi" />
</AnchorPane>
I am new to javafX, have run through various tutorials, and googled extensively. I am attempting to write a multiscreen javaFX program whose second screen has a split pane, whose right pane should display a grid and a button. The framework I am using for multiple screens is copied form Angela Caiedo's MultipleScreens Framework tutorial ( https://github.com/acaicedo/JFX-MultiScreen/tree/master/ScreensFramework) .
What works: The screens framework is successful in terms of flipping between my multiple screens.
My problem: I click the button on screen 1 to move to screen 2. Screen 2 successfully shows. On screen 2 I click a button to populate data in my vBox. The code in my controller class for screen 2 is unable to access the vbox (or any other defined containers on this screen).
My main class sets up the controller screens.
public class FieldMapCreator extends Application {
public static String mainID = "main";
public static String mainFile = "MainMapFXMLDocument.fxml";
public static String initialMapID = "initialMap";
public static String initialMapFile = "FXMLMapPicture.fxml";
#Override
public void start(Stage stage) throws Exception {
ScreensController mainContainer = new ScreensController();
mainContainer.loadScreen(FieldMapCreator.mainID, FieldMapCreator.mainFile);
mainContainer.loadScreen(FieldMapCreator.initialMapID, FieldMapCreator.initialMapFile);
mainContainer.setScreen(FieldMapCreator.mainID);
Group root = new Group();
root.getChildren().addAll(mainContainer);
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
}
I get to the second screen by clicking a button on screen 1. Button1 code looks like:
#FXML
private void initialMapButtonAction(ActionEvent event) {
myController.setScreen(FieldMapCreator.initialMapID);
}
Screen 2 has a button that when clicked executes a method that creates data for the vbox. The fxml for screen 2 is this:
<AnchorPane id="AnchorPane" fx:id="mainAnchorPane" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8.0.40" xmlns:fx="http://javafx.com/fxml/1" fx:controller="FieldMapCreator.FXMLMapPictureController">
<children>
<SplitPane fx:id="mapSplitPane" dividerPositions="0.29797979797979796" layoutX="3.0" layoutY="7.0" prefHeight="400.0" prefWidth="600.0">
<items>
<AnchorPane fx:id="anchorPaneLeft" minHeight="0.0" minWidth="0.0" prefHeight="160.0" prefWidth="100.0">
<children>
<Button fx:id="backButton" layoutX="14.0" layoutY="348.0" mnemonicParsing="false" onAction="#goToMainScreen" text="Back" />
</children>
</AnchorPane>
<AnchorPane fx:id="anchorPaneRight" minHeight="0.0" minWidth="0.0" prefHeight="364.0" prefWidth="401.0">
<children>
<Button fx:id="vBoxShowMap" layoutX="24.0" layoutY="346.0" mnemonicParsing="false" onAction="#buildMapFromNurseries" prefHeight="26.0" prefWidth="91.0" text="show map" />
<VBox fx:id="mapVBox" layoutX="24.0" layoutY="24.0" onMouseClicked="#vBoxMouseClicked" prefHeight="200.0" prefWidth="309.0" />
</children></AnchorPane>
</items>
</SplitPane>
</children>
</AnchorPane>
The code that fails is in the "showInitialMap()" method of the controller class for screen 2. When executed, the last line of this method "mapVBox.getChildren().add(root)", results in a null pointer exception. I expected this to be resolved via the fxml injection. I also tried the commented out code to retrieve "mapVBox" using scene lookup, but it also results in a null pointer exception. The controller code is below:
public class FXMLMapPictureController implements Initializable, ControlledScreen {
ScreensController myController;
static MyNode[][] mainField ;
#FXML
private AnchorPane mainAnchorPane;
#FXML
private static SplitPane mapSplitPane;
#FXML
private AnchorPane anchorPaneLeft;
#FXML
private static AnchorPane anchorPaneRight;
#FXML
private static VBox mapVBox;
#FXML
private Button vBoxShowMap;
/**
* Initializes the controller class.
*/
#Override
public void initialize(URL url, ResourceBundle rb) {
// Should something be in here ??
}
public void goToMainScreen() {
myController.setScreen(FieldMapCreator.mainID);
}
public void showInitialMap() {
int row = userFieldMap.getNumRows();
int col = userFieldMap.getNumCols();
double gridWidth = 309/col;
double gridHeight = 200/row;
Group root = new Group();
// initialize the field
for (int idx = 0; idx < col; idx++) {
for (int jdx = 0; jdx < row; jdx++) {
// create plot
Plot plot = new Plot(idx, jdx, "Plot" + idx + "/" + jdx);
// Create node to hold the Plot
MyNode node = new MyNode(idx*gridWidth, jdx*gridHeight, gridWidth, gridHeight, plot);
// add plot to group
root.getChildren().add(node);
}
}
//Scene myScene = myController.getScene();
//VBox mapVBox = (VBox)myScene.lookup("#mapVBox");
mapVBox.getChildren().add(root);
}
#Override
public void setScreenParent(ScreensController screenParent) {
myController = screenParent;
}
Is there something missing from the initialize() method? I'm wondering if I am not setting something correctly when I change screens. I am able to access the initial screen's containers without problem from all screen 1 methods including the initialize class. When I attempt the same in screen 2, I get the message "screen hasn't been loaded !!!"
Thanks for any help you can provide.
You are using static fields as FXML injection targets which don't work in Java 8 and should not have been implemented to work in any other version, as static UI elements just don't make sense. Here's a bit more detailed answer. Having resorted to a static field most of the time means the software design of the application needs to be reconsidered.