UI Widget Patterns

Reusable patterns for building menus, dialogs, and HUD elements using Frame, Caption, and Sprite components. These patterns work independently of Grids.

Related Pages:

UI-Component-Hierarchy - Base UI components
Input-and-Events - Event handler reference
Animation-System - Animating widget transitions

Setup Template

Most widget patterns fit into this basic structure:

import mcrfpy

# Create scene and get UI collection
mcrfpy.createScene("menu")
ui = mcrfpy.sceneUI("menu")

# Load assets
font = mcrfpy.Font("assets/fonts/mono.ttf")
# texture = mcrfpy.Texture("assets/ui_sprites.png", grid_size=(16, 16))

# Create root container for the menu/HUD
root = mcrfpy.Frame(pos=(50, 50), size=(300, 400))
root.fill_color = mcrfpy.Color(30, 30, 40)
root.outline_color = mcrfpy.Color(80, 80, 100)
root.outline = 2
ui.append(root)

# Add widgets to root.children...

mcrfpy.setScene("menu")

Button

A clickable frame with label and hover feedback.

def make_button(parent, pos, text, on_click):
    """Create a button with hover effects."""
    btn = mcrfpy.Frame(pos=pos, size=(120, 32))
    btn.fill_color = mcrfpy.Color(60, 60, 80)
    btn.outline_color = mcrfpy.Color(100, 100, 140)
    btn.outline = 1

    label = mcrfpy.Caption(pos=(10, 6), text=text)
    label.fill_color = mcrfpy.Color(220, 220, 220)
    btn.children.append(label)

    # Hover effects
    def on_enter():
        btn.fill_color = mcrfpy.Color(80, 80, 110)
        btn.outline_color = mcrfpy.Color(140, 140, 180)

    def on_exit():
        btn.fill_color = mcrfpy.Color(60, 60, 80)
        btn.outline_color = mcrfpy.Color(100, 100, 140)

    btn.on_enter = on_enter
    btn.on_exit = on_exit
    btn.on_click = lambda x, y, btn: on_click()

    parent.children.append(btn)
    return btn

# Usage
make_button(root, (20, 20), "New Game", lambda: mcrfpy.setScene("game"))
make_button(root, (20, 60), "Options", lambda: show_options())
make_button(root, (20, 100), "Quit", lambda: mcrfpy.exit())

Toggle / Checkbox

A button that toggles state and updates its appearance.

def make_toggle(parent, pos, label_text, initial=False, on_change=None):
    """Create a toggle with visual state indicator."""
    state = {"checked": initial}

    frame = mcrfpy.Frame(pos=pos, size=(160, 28))
    frame.fill_color = mcrfpy.Color(40, 40, 50)

    # Checkbox indicator
    indicator = mcrfpy.Frame(pos=(6, 6), size=(16, 16))
    indicator.outline = 1
    indicator.outline_color = mcrfpy.Color(120, 120, 140)
    frame.children.append(indicator)

    # Label
    label = mcrfpy.Caption(pos=(30, 5), text=label_text)
    label.fill_color = mcrfpy.Color(200, 200, 200)
    frame.children.append(label)

    def update_visual():
        if state["checked"]:
            indicator.fill_color = mcrfpy.Color(100, 180, 100)
        else:
            indicator.fill_color = mcrfpy.Color(50, 50, 60)

    def toggle(x, y, btn):
        state["checked"] = not state["checked"]
        update_visual()
        if on_change:
            on_change(state["checked"])

    frame.on_click = toggle
    update_visual()

    parent.children.append(frame)
    return state  # Return state dict for external access

# Usage
music_toggle = make_toggle(root, (20, 20), "Music", initial=True,
                           on_change=lambda on: set_music_volume(1.0 if on else 0.0))

A list of selectable options with keyboard navigation support.

class VerticalMenu:
    def __init__(self, parent, pos, options, on_select):
        """
        options: list of (label, value) tuples
        on_select: callback(value) when option chosen
        """
        self.options = options
        self.on_select = on_select
        self.selected = 0

        self.frame = mcrfpy.Frame(pos=pos, size=(180, len(options) * 28 + 8))
        self.frame.fill_color = mcrfpy.Color(35, 35, 45)
        parent.children.append(self.frame)

        self.items = []
        for i, (label, value) in enumerate(options):
            item = mcrfpy.Caption(pos=(12, 4 + i * 28), text=label)
            item.fill_color = mcrfpy.Color(180, 180, 180)
            self.frame.children.append(item)
            self.items.append(item)

        self._update_highlight()

    def _update_highlight(self):
        for i, item in enumerate(self.items):
            if i == self.selected:
                item.fill_color = mcrfpy.Color(255, 220, 100)
            else:
                item.fill_color = mcrfpy.Color(180, 180, 180)

    def move_up(self):
        self.selected = (self.selected - 1) % len(self.options)
        self._update_highlight()

    def move_down(self):
        self.selected = (self.selected + 1) % len(self.options)
        self._update_highlight()

    def confirm(self):
        _, value = self.options[self.selected]
        self.on_select(value)

# Usage
menu = VerticalMenu(root, (20, 20), [
    ("Continue", "continue"),
    ("New Game", "new"),
    ("Options", "options"),
    ("Quit", "quit")
], on_select=handle_menu_choice)

def handle_key(key, pressed):
    if not pressed:
        return
    if key == "Up":
        menu.move_up()
    elif key == "Down":
        menu.move_down()
    elif key == "Enter":
        menu.confirm()

mcrfpy.keypressScene(handle_key)

A dialog that captures all input until dismissed.

class ModalDialog:
    def __init__(self, message, on_dismiss=None):
        self.on_dismiss = on_dismiss
        self.ui = mcrfpy.sceneUI(mcrfpy.currentScene())

        # Semi-transparent backdrop
        self.backdrop = mcrfpy.Frame(pos=(0, 0), size=(1024, 768))
        self.backdrop.fill_color = mcrfpy.Color(0, 0, 0, 160)
        self.backdrop.z_index = 900
        self.backdrop.on_click = lambda x, y, b: None  # Block clicks
        self.ui.append(self.backdrop)

        # Dialog box
        self.dialog = mcrfpy.Frame(pos=(312, 284), size=(400, 200))
        self.dialog.fill_color = mcrfpy.Color(50, 50, 65)
        self.dialog.outline_color = mcrfpy.Color(120, 120, 150)
        self.dialog.outline = 2
        self.dialog.z_index = 901
        self.ui.append(self.dialog)

        # Message
        msg = mcrfpy.Caption(pos=(20, 20), text=message)
        msg.fill_color = mcrfpy.Color(220, 220, 220)
        self.dialog.children.append(msg)

        # OK button
        ok_btn = mcrfpy.Frame(pos=(150, 140), size=(100, 36))
        ok_btn.fill_color = mcrfpy.Color(70, 100, 70)
        ok_btn.outline = 1
        ok_btn.outline_color = mcrfpy.Color(100, 150, 100)
        ok_btn.on_click = lambda x, y, b: self.close()
        self.dialog.children.append(ok_btn)

        ok_label = mcrfpy.Caption(pos=(35, 8), text="OK")
        ok_label.fill_color = mcrfpy.Color(220, 255, 220)
        ok_btn.children.append(ok_label)

        # Capture keyboard
        self._prev_handler = None
        self._install_key_handler()

    def _install_key_handler(self):
        def modal_keys(key, pressed):
            if pressed and key in ("Enter", "Escape"):
                self.close()
        mcrfpy.keypressScene(modal_keys)

    def close(self):
        self.ui.remove(self.backdrop)
        self.ui.remove(self.dialog)
        if self.on_dismiss:
            self.on_dismiss()

# Usage
def show_message(text):
    ModalDialog(text)

show_message("Game saved successfully!")

Hotbar / Quick Slots

Number keys (1-9) mapped to inventory slots.

class Hotbar:
    def __init__(self, parent, pos, slot_count=9):
        self.slots = []
        self.items = [None] * slot_count  # Item data per slot
        self.selected = 0

        self.frame = mcrfpy.Frame(pos=pos, size=(slot_count * 36 + 8, 44))
        self.frame.fill_color = mcrfpy.Color(30, 30, 40, 200)
        parent.children.append(self.frame)

        for i in range(slot_count):
            slot = mcrfpy.Frame(pos=(4 + i * 36, 4), size=(32, 32))
            slot.fill_color = mcrfpy.Color(50, 50, 60)
            slot.outline = 1
            slot.outline_color = mcrfpy.Color(80, 80, 100)
            self.frame.children.append(slot)
            self.slots.append(slot)

            # Slot number label
            num = mcrfpy.Caption(pos=(2, 2), text=str((i + 1) % 10))
            num.fill_color = mcrfpy.Color(100, 100, 120)
            slot.children.append(num)

        self._update_selection()

    def _update_selection(self):
        for i, slot in enumerate(self.slots):
            if i == self.selected:
                slot.outline_color = mcrfpy.Color(200, 180, 80)
                slot.outline = 2
            else:
                slot.outline_color = mcrfpy.Color(80, 80, 100)
                slot.outline = 1

    def select(self, index):
        if 0 <= index < len(self.slots):
            self.selected = index
            self._update_selection()

    def use_selected(self):
        item = self.items[self.selected]
        if item:
            item.use()

    def set_item(self, index, item):
        self.items[index] = item
        # Update slot visual (add sprite, etc.)

# Usage
hotbar = Hotbar(root, (200, 700))

def handle_key(key, pressed):
    if not pressed:
        return
    # Number keys select slots
    if key.startswith("Num") and len(key) == 4:
        num = int(key[3])
        index = (num - 1) if num > 0 else 9
        hotbar.select(index)
    elif key == "E":
        hotbar.use_selected()

mcrfpy.keypressScene(handle_key)

Draggable Window

A frame that can be dragged by its title bar.

class DraggableWindow:
    def __init__(self, parent, pos, size, title):
        self.dragging = False
        self.drag_offset = (0, 0)

        self.frame = mcrfpy.Frame(pos=pos, size=size)
        self.frame.fill_color = mcrfpy.Color(45, 45, 55)
        self.frame.outline = 1
        self.frame.outline_color = mcrfpy.Color(100, 100, 120)
        parent.children.append(self.frame)

        # Title bar
        self.title_bar = mcrfpy.Frame(pos=(0, 0), size=(size[0], 24))
        self.title_bar.fill_color = mcrfpy.Color(60, 60, 80)
        self.frame.children.append(self.title_bar)

        title_label = mcrfpy.Caption(pos=(8, 4), text=title)
        title_label.fill_color = mcrfpy.Color(200, 200, 220)
        self.title_bar.children.append(title_label)

        # Content area reference
        self.content_y = 28

        # Drag handling
        def start_drag(x, y, btn):
            if btn == 0:  # Left click
                self.dragging = True
                frame_pos = self.frame.pos
                self.drag_offset = (x - frame_pos[0], y - frame_pos[1])

        def on_move(x, y):
            if self.dragging:
                new_x = x - self.drag_offset[0]
                new_y = y - self.drag_offset[1]
                self.frame.pos = (new_x, new_y)

        def stop_drag():
            self.dragging = False

        self.title_bar.on_click = start_drag
        self.title_bar.on_move = on_move
        self.title_bar.on_exit = stop_drag

# Usage
window = DraggableWindow(root, (100, 100), (250, 300), "Inventory")

# Add content to window.frame.children at y >= window.content_y
item_list = mcrfpy.Caption(pos=(10, window.content_y + 10), text="Items here...")
window.frame.children.append(item_list)

Input-and-Events - Event handler API reference
Grid-Interaction-Patterns - Patterns for grid-based gameplay
Animation-System - Animating widget transitions

Last updated: 2025-11-29

UI Widget Patterns

Setup Template

Button

Toggle / Checkbox

Vertical Menu

Modal Dialog

Hotbar / Quick Slots

Draggable Window

Related Pages