Adding an anchorpane from FXML and swapping it into current scene - javafx

Question

I have been having some issues with a project i am working on. I wish to load my fxml content into an existing anchorpane and display it when the "next" button is clicked, I also wish to have the "back" button to set the anchorpane to the previous fxml file.
The issue I am having is that I have it working only once. If next is clicked it shows the correct fxml content, however if back is pressed it operates correctly once, the second time the window displayed contains no content:
#FXML
AnchorPane scenePane, allContent;
#FXML
public void handleNextAction() {
try {
scenePane.getChildren().clear();
AnchorPane newvalscene = (AnchorPane) FXMLLoader.load(getClass().getResource("ProjectDetails.fxml"));
scenePane.getChildren().setAll(newvalscene.getChildren());
} catch (IOException ex) {
Logger.getLogger(NewProjectController.class.getName()).log(Level.SEVERE, null, ex);
}
}
#FXML
public void handleBackAction() {
try {
// allContent.getChildren().clear();
AnchorPane newvalscene = (AnchorPane) FXMLLoader.load(getClass().getResource("newProjectWindow.fxml"));
allContent.getChildren().setAll(newvalscene.getChildren());
} catch (IOException ex) {
Logger.getLogger(NewProjectController.class.getName()).log(Level.SEVERE, null, ex);
}
}
I have tried clearing the content of the anchorpanes however this just results in the anchorpane being empty with no content loaded from the FXML the second time the back button is pressed.
Note I tried debugging this but since there is no actual error its hard to trace and netbeans wont seem to show me the content of variables newvalscene which contains all the nodes to be rendered, but a println shows that it does contain the Vbox and children i expect to be shown.
Any help would be appreciated.

Answer 1

why all these SIr is there a reason ?
scenePane.getChildren().clear();
scenePane.getChildren().setAll(newvalscene.getChildren());//why replace?
allContent.getChildren().setAll(newvalscene.getChildren());//why replace ?
please try this
if you really have this
AnchorPane scenePane, allContent;
and scenePane is your Parent or Root, you can nest your items like
scenePane.getCHildren().add(child);
so relating to your codes
AnchorPane nextvalscene,backvalscene;
public void handleNextAction() {
try {
//scenePane.getChildren().clear(); remove this
if(nextvalscene == null){
nextvalscene = (AnchorPane) FXMLLoader.load(getClass().getResource("ProjectDetails.fxml"));
scenePane.getChildren().add(newvalscene);//change setAll to add and use the child itself
AnchorPane.setLeftNode(newvalscene, 0.0);//set constraint for your newvalscene AnchorPane
//do that for the rest esp top
}
nextvalscene.toFront();
} catch (IOException ex) {
Logger.getLogger(NewProjectController.class.getName()).log(Level.SEVERE, null, ex);
}
}
do same for handleBackAction
Logic is your parent or root scene is AnchorPane it can contain children, so no need to replace all its children, you can have them all inside by obscured by constraints on layout parameters, and change its re-ordering.
unless you have a reason to copying your Anchorpane's children to your scene children list, i think i missed
hope it helps