Duplicating a HBox and its children

[bright ice]

How would I go about duplicating a HBox I have and its children?
I have a Scroll Pane -> VBox -> HBox in this hierarchy. The HBox contains an ImageLabel, 3 labels and an anchor pane that has a button inside of it.

I tried asking ChatGPT but it seems unrealistically overcomplicated for something as simple as this, I want to duplicate the HBox for the simple purpose of adding items to a list.

[severe jolt]

<@&987246487241105418> please have a look, thanks.

[turbid pier]

you want to duplicate to replicate the behaviour of a list?

why not use the proper ui element in the first place?

There is a ListView you can use

[bright ice]

No the behavior of the list isn't the issue it works just how I want it with a VBox and scroll pane, all the elements form a shopping cart list effectively.

So imagine you add an item, I'm trying to clone the HBox and all its children so I can then edit the duplicated children to have the correct name, price, image etc.

ChatGPT gave me this

// Assuming you have an existing VBox and HBox
VBox vbox = new VBox();
HBox originalHBox = new HBox();

// Add some children to the original HBox for demonstration
Button button1 = new Button("Button 1");
Label label1 = new Label("Label 1");
originalHBox.getChildren().addAll(button1, label1);

// Add the original HBox to the VBox
vbox.getChildren().add(originalHBox);

// Now, create a method to duplicate the HBox
public HBox duplicateHBox(HBox originalHBox) {
    HBox newHBox = new HBox();
    
    // Loop through the original HBox's children and add them to the new HBox
    for (Node child : originalHBox.getChildren()) {
        // Depending on the type of node, create a new instance and copy relevant properties
        if (child instanceof Button) {
            Button originalButton = (Button) child;
            Button newButton = new Button(originalButton.getText());
            newHBox.getChildren().add(newButton);
        } else if (child instanceof Label) {
            Label originalLabel = (Label) child;
            Label newLabel = new Label(originalLabel.getText());
            newHBox.getChildren().add(newLabel);
        }
        // You can add other types of nodes as needed
    }
    
    return newHBox;
}

// Duplicate the HBox and add it to the VBox
HBox duplicatedHBox = duplicateHBox(originalHBox);
vbox.getChildren().add(duplicatedHBox);

but this seems lowkey ridiculous as I said for something as simple as duplicating an element and its children?

[severe jolt]

Detected code, here are some useful tools:

[turbid pier]

I am going to ask this again, if you want a list then use the correct ui element (ListView)

[bright ice]

Am I able to put an ImageLabel and multiple labels inside of each row of the list in a listview?

[turbid pier]

yeah

you end up with a ListView<HBox> and then put that into a scroll pane

you could also make a custom class that extends HBox to represent your element

[bright ice]

I can't put a HBox inside of a ListView?

[turbid pier]

ah well that doesnt make sense, you would instead have ListView<ShoppingEntry> and then a custom renderer for that class

[bright ice]

Also even if I have a ListView I still have the problem of needing to duplicate all elements and children elements

Which is what I was having trouble with

[turbid pier]

why do you want to duplicate elements (children) in the first place?

also even if it doesnt fix your current issue you should still use ListView if you want a visual list

[bright ice]

Its a shopping cart

If I have add a new item in there

there needs to be a new instance of HBox to display that item

and that items attributes

[turbid pier]

yes

but there is no duplication that happens here

[bright ice]

Wdym?

[turbid pier]

why do you want to duplicate?

visually you can call that duplication

but in code thats not what happens

[bright ice]

Yes I mean visually

As if I went into scene builder

clicked on the HBox element

[turbid pier]

you would define a general render strategy that creates a new HBox for each entry

[bright ice]

and selected "duplicate"

[bright ice]

so I could overwrite the constructor and give it the properties I want so theyre the same as what format i've already built in scene builder?

[turbid pier]

so I would basically create a class that generally defines an entry

ShoppingItem or whatever

then visually use a ListView<ShoppingItem> and change the cell factory to define how a single item should be visually rendered

[bright ice]

So theres no way I can just clone these elements from their fxid? Nothing simpler than that? Seems like a lot of effort for such a basic thign

[turbid pier]

what do you even mean by clone

based on the information I know that ListView is what you want

[bright ice]

"As if I went into scene builder
clicked on the HBox element
and selected "duplicate""

listview cant contain a HBox or an imageLabel so its not

[turbid pier]

you misunderstanding how ListView works

its not something you fully setup in the fxml

but in actual code

[bright ice]

does it not just work off of an array?

[turbid pier]

because your data (ShoppingEntry) is also defined in your code

[turbid pier]

what kind of array? and how is javafx supposed to know how to render it?

[bright ice]

Im asking if it works off of an array I dont know

[turbid pier]

what?

[bright ice]

https://gyazo.com/83fa60a5d9d60f31299429a08bcbcc60

this is literally all i want to do in the code

[turbid pier]

yeah

you want a ListView

A ListView displays a horizontal or vertical list of items from which the user may select, or with which the user may interact. A ListView is able to have its generic type set to represent the type of data in the backing model.

[bright ice]

Ok suppose I go with that

ListView listView = new ListView();

    listView.getItems().add("Item 1");
    listView.getItems().add("Item 2");
    listView.getItems().add("Item 3");

heres some code i found

How do I go about adding the button and the imagelabel as well

or the description too

in the same line

[turbid pier]

cell factory

its used to define how a single item should be rendered

using the entry and its data

[bright ice]

Do you have any good resources I can go to for reference on how to do this

ListView tutorials are all just extremely basic

array of strings they are displaying

[turbid pier]

https://openjfx.io/javadoc/23/javafx.controls/javafx/scene/control/ListView.html#customizing-listview-visuals-heading

this probably

but it doesnt show it visually

otherwise might check one of these resources:

[severe jolt]

JavaFX Tutorials

Official Documentation

• Project Setup: https://openjfx.io/openjfx-docs/
• API JavaDocs: https://openjfx.io/javadoc/23/
• Introduction to FXML: https://openjfx.io/javadoc/23/javafx.fxml/javafx/fxml/doc-files/introduction_to_fxml.html
• CSS Reference: https://openjfx.io/javadoc/23/javafx.graphics/javafx/scene/doc-files/cssref.html

Community & Tutorials

• FXDocs: https://fxdocs.github.io/docs/html5/
• Jenkov Tutorials: https://jenkov.com/tutorials/javafx/index.html
• Fundamentals (dev.java): https://dev.java/learn/javafx/

Additional Tools:

• Scene Builder: https://gluonhq.com/products/scene-builder/

squidxtv • used /tag id: javafx-tutorials · Oct 15, 2024, 12:03 PM

[turbid pier]

I can give a simple example (might be incomplete)

[bright ice]

That would be super helpful

[turbid pier]

but before: are you familiar with records in java?

[bright ice]

nope

[turbid pier]

ok then I am not going to use them in the example

This kinda represents your data as a class right?

// Data model:
public class ShoppingItem {

    private String name;
    private String description;
    private double price;

    // constructor, getter and setter
}

[bright ice]

yeah more or less

[turbid pier]

yeah thats enough

ListView<ShoppingItem> cart = new ListView<>();

// add example data
cart.getItems().addAll(
    new ShoppingItem("Apples", "...", 1.0),
    new ShoppingItem("Water", "...", 1.0),
    // ...
);

cart.setCellFactory(list -> { // list is the current ListView<ShoppingItem>
    // needs to return ListCell<ShoppingItem>
    return new ListCell<>() {
        @Override
        protected void updateItem(ShoppingItem item, boolean empty) {
            super.updateItem(item, empty);

            if (item == null || empty) {
                setGraphic(null);
            } else {
                // uses data (item) and create the ui element that represents it (HBox)
                HBox visual = new HBox(
                    new Label(item.getName()),
                    new Label(item.getDescription)),
                    new Label(String.valueOf(item.getPrice()))
                );
                
                // tells the ListCell to use that Hbox to render that item
                setGraphic(visual);
            }
        }
    }
});

// now use the list to render in some element

I hope that helps

[bright ice]

Appreciate it I'll let you know how I go

[turbid pier]

so to sum up:
ListView is responsible for storing your entries
it uses the cell factory to render the items accordingly

it dynamically renders the elements, so you basically add new entries and it renders them using the cell factory