Abstract Screen

AbstractScreen is the entry point for most custom UIs in UI Lib. It extends the vanilla net.minecraft.client.gui.screens.Screen class but implements the UI Lib IScreen interface.

This class is intended for GUIs that do not involve an inventory (Container/Menu), such as:

• Main Menus
• Configuration Screens
• Lore Books
• Skill Trees
• Selection Wheels

The IScreen Interface

The magic of UI Lib happens through the IScreen interface. When your screen implements this (which AbstractScreen does automatically), UI Lib's Mixins (ScreenMixin, ScreenAccessor) hook into the vanilla rendering and event logic.

This provides you with:

1. Component Management: A centralized list of IComponent objects.
2. Widget Integration: Seamless handling of IWidget objects (Vanilla widgets with relative positioning).
3. Background Rendering: An API to replace the default "Dirt" background with Blur, Gradients, or Panoramas.

Implementation Guide

To create a screen, create a class extending AbstractScreen.

1. Constructor

You must pass a Component title to the super constructor. This title is used by the Narrator.

public class MyCustomScreen extends AbstractScreen {
    public MyCustomScreen() {
        super(Component.literal("My Screen Title"));
        
        // Optional: Set a background immediately
        this.setBackground(new BlurredBackground());
    }
}

2. Initialization (init)

The init() method is called when the screen is opened and every time the window is resized.

Do not use the constructor for layout!

Never create your components or widgets inside the constructor. The screen width and height are not guaranteed to be correct until init() is called.

Use init() to instantiate and add your components.

@Override
protected void init() {
    // 1. Clear previous elements (handled by super, but good practice to know)
    super.init();

    // 2. Define Layout Variables
    int centerX = this.width / 2;
    int centerY = this.height / 2;

    // 3. Add Components
    TextComponent title = new TextComponent(0, 0, Component.literal("Settings"));
    title.setTextAlign(TextAlign.CENTER);
    title.updateParentPosition(centerX, centerY - 50, this.width, this.height);
    this.addComponent(title);

    // 4. Add Widgets
    ButtonWidget closeBtn = new ButtonWidget(0, 0, 100, 20, Component.literal("Close"), (b) -> onClose());
    closeBtn.uilib$updateParentPosition(centerX - 50, centerY + 20);
    this.addWidget(closeBtn);
}

Adding Elements

addComponent(IComponent component)

Adds a visual component. These are added to the internal render list.

• Note: Components are rendered in the order they are added.

addWidget(IWidget widget)

Adds an interactive widget.

• Crucial: This method adds the widget to the Renderable, GuiEventListener, and NarratableEntry lists of the screen.
• Why? In vanilla, you often have to call addRenderableWidget or addRenderableOnly. UI Lib simplifies this into one method that detects the widget's capabilities.

Background Management

You do not need to override renderBackground manually. Use the setter methods:

• setBackground(IBackground bg): Sets the renderer.
• getBackground(): Retrieves current background.
• clearBackground(): Removes the background (renders nothing behind components).

See Backgrounds for available types.

Lifecycle Methods

While AbstractScreen handles most things, you can still override vanilla methods if needed:

• render(GuiGraphics, int mouseX, int mouseY, float partialTick): The main loop. Call super.render to draw your components.
• onClose(): Called when ESC is pressed or the screen is closed.
• tick(): Called every game tick (20 times/second). Useful for animation logic.