Robius Widget Patterns
PassedA comprehensive reference for Makepad/Robius widget development patterns. Provides production-ready code patterns for modals, tooltips, collapsible sections, drag-and-drop, grid layouts, LRU caching, hover effects, and responsive adaptive views extracted from real codebases like Robrix and Moly.
Skill Content
12,312 charactersRobius Widget Patterns Skill
Best practices for designing reusable Makepad widgets based on Robrix and Moly codebase patterns.
Source codebases:
- Robrix: Matrix chat client - Avatar, RoomsList, RoomScreen widgets
- Moly: AI chat application - Slot, ChatLine, PromptInput, AdaptiveView widgets
Triggers
Use this skill when:
- Creating reusable Makepad widgets
- Designing widget component APIs
- Implementing text/image toggle patterns
- Dynamic styling in Makepad
- Keywords: robrix widget, makepad component, reusable widget, widget design pattern
Production Patterns
For production-ready widget patterns, see the _base/ directory:
| Pattern | Description | |---------|-------------| | 01-widget-extension | Add helper methods to widget references | | 02-modal-overlay | Popups, dialogs using DrawList2d overlay | | 03-collapsible | Expandable/collapsible sections | | 04-list-template | Dynamic lists with LivePtr templates | | 05-lru-view-cache | Memory-efficient view caching | | 14-callout-tooltip | Tooltips with arrow positioning | | 20-redraw-optimization | Efficient redraw patterns | | 15-dock-studio-layout | IDE-style resizable panels | | 16-hover-effect | Hover effects with instance variables | | 17-row-based-grid-layout | Dynamic grid layouts | | 18-drag-drop-reorder | Drag-and-drop widget reordering | | 19-pageflip-optimization | PageFlip 切换优化,即刻销毁/缓存模式 |
Standard Widget Structure
use makepad_widgets::*;
live_design! {
use link::theme::*;
use link::widgets::*;
pub MyWidget = {{MyWidget}} {
width: Fill, height: Fit,
flow: Down,
// Child widgets defined in DSL
inner_view = <View> {
// ...
}
}
}
#[derive(Live, LiveHook, Widget)]
pub struct MyWidget {
#[deref] view: View, // Delegate to inner View
#[live] some_property: f64, // DSL-configurable property
#[live(100.0)] default_val: f64, // With default value
#[rust] internal_state: State, // Rust-only state (not in DSL)
#[animator] animator: Animator, // For animations
}
impl Widget for MyWidget {
fn handle_event(&mut self, cx: &mut Cx, event: &Event, scope: &mut Scope) {
self.view.handle_event(cx, event, scope);
// Custom event handling...
}
fn draw_walk(&mut self, cx: &mut Cx2d, scope: &mut Scope, walk: Walk) -> DrawStep {
self.view.draw_walk(cx, scope, walk)
}
}
Text/Image Toggle Pattern
A common pattern for widgets that show either text or an image (like avatars):
live_design! {
pub Avatar = {{Avatar}} {
width: 36.0, height: 36.0,
align: { x: 0.5, y: 0.5 }
flow: Overlay, // Stack views on top of each other
text_view = <View> {
visible: true, // Default visible
show_bg: true,
draw_bg: {
uniform background_color: #888888
fn pixel(self) -> vec4 {
let sdf = Sdf2d::viewport(self.pos * self.rect_size);
let c = self.rect_size * 0.5;
sdf.circle(c.x, c.x, c.x)
sdf.fill_keep(self.background_color);
return sdf.result
}
}
text = <Label> {
text: "?"
}
}
img_view = <View> {
visible: false, // Hidden by default
img = <Image> {
fit: Stretch,
width: Fill, height: Fill,
}
}
}
}
#[derive(LiveHook, Live, Widget)]
pub struct Avatar {
#[deref] view: View,
#[rust] info: Option<UserInfo>,
}
impl Avatar {
/// Show text content, hiding the image
pub fn show_text<T: AsRef<str>>(
&mut self,
cx: &mut Cx,
bg_color: Option<Vec4>,
info: Option<AvatarTextInfo>,
username: T,
) {
self.info = info.map(|i| i.into());
// Get first character
let first_char = utils::first_letter(username.as_ref())
.unwrap_or("?").to_uppercase();
self.label(ids!(text_view.text)).set_text(cx, &first_char);
// Toggle visibility
self.view(ids!(text_view)).set_visible(cx, true);
self.view(ids!(img_view)).set_visible(cx, false);
// Apply optional background color
if let Some(color) = bg_color {
self.view(ids!(text_view)).apply_over(cx, live! {
draw_bg: { background_color: (color) }
});
}
}
/// Show image content, hiding the text
pub fn show_image<F, E>(
&mut self,
cx: &mut Cx,
info: Option<AvatarImageInfo>,
image_set_fn: F,
) -> Result<(), E>
where
F: FnOnce(&mut Cx, ImageRef) -> Result<(), E>
{
let img_ref = self.image(ids!(img_view.img));
let res = image_set_fn(cx, img_ref);
if res.is_ok() {
self.view(ids!(img_view)).set_visible(cx, true);
self.view(ids!(text_view)).set_visible(cx, false);
self.info = info.map(|i| i.into());
}
res
}
/// Check current display status
pub fn status(&mut self) -> DisplayStatus {
if self.view(ids!(img_view)).visible() {
DisplayStatus::Image
} else {
DisplayStatus::Text
}
}
}
Dynamic Styling with apply_over
Apply dynamic styles at runtime:
// Apply single property
self.view(ids!(content)).apply_over(cx, live! {
draw_bg: { color: #ff0000 }
});
// Apply multiple properties
self.view(ids!(message)).apply_over(cx, live! {
padding: { left: 20, right: 20 }
margin: { top: 10 }
});
// Apply with variables
let highlight_color = if is_selected { vec4(1.0, 0.0, 0.0, 1.0) } else { vec4(0.5, 0.5, 0.5, 1.0) };
self.view(ids!(item)).apply_over(cx, live! {
draw_bg: { color: (highlight_color) }
});
Widget Reference Pattern
Implement *Ref methods for external API:
impl AvatarRef {
/// See [`Avatar::show_text()`].
pub fn show_text<T: AsRef<str>>(
&self,
cx: &mut Cx,
bg_color: Option<Vec4>,
info: Option<AvatarTextInfo>,
username: T,
) {
if let Some(mut inner) = self.borrow_mut() {
inner.show_text(cx, bg_color, info, username);
}
}
/// See [`Avatar::show_image()`].
pub fn show_image<F, E>(
&self,
cx: &mut Cx,
info: Option<AvatarImageInfo>,
image_set_fn: F,
) -> Result<(), E>
where
F: FnOnce(&mut Cx, ImageRef) -> Result<(), E>
{
if let Some(mut inner) = self.borrow_mut() {
inner.show_image(cx, info, image_set_fn)
} else {
Ok(())
}
}
}
Collapsible/Expandable Pattern
live_design! {
pub CollapsibleSection = {{CollapsibleSection}} {
flow: Down,
header = <View> {
cursor: Hand,
icon = <Icon> { }
title = <Label> { text: "Section" }
}
content = <View> {
visible: false,
// Expandable content here
}
}
}
#[derive(Live, LiveHook, Widget)]
pub struct CollapsibleSection {
#[deref] view: View,
#[rust] is_expanded: bool,
}
impl CollapsibleSection {
pub fn toggle(&mut self, cx: &mut Cx) {
self.is_expanded = !self.is_expanded;
self.view(ids!(content)).set_visible(cx, self.is_expanded);
// Rotate icon
let rotation = if self.is_expanded { 90.0 } else { 0.0 };
self.view(ids!(header.icon)).apply_over(cx, live! {
draw_icon: { rotation: (rotation) }
});
self.redraw(cx);
}
}
Loading State Pattern
live_design! {
pub LoadableContent = {{LoadableContent}} {
flow: Overlay,
content = <View> {
visible: true,
// Main content
}
loading_overlay = <View> {
visible: false,
show_bg: true,
draw_bg: { color: #00000088 }
align: { x: 0.5, y: 0.5 }
<BouncingDots> { }
}
error_view = <View> {
visible: false,
error_label = <Label> { }
}
}
}
#[derive(Live, LiveHook, Widget)]
pub struct LoadableContent {
#[deref] view: View,
#[rust] state: LoadingState,
}
pub enum LoadingState {
Idle,
Loading,
Loaded,
Error(String),
}
impl LoadableContent {
pub fn set_state(&mut self, cx: &mut Cx, state: LoadingState) {
self.state = state;
match &self.state {
LoadingState::Idle | LoadingState::Loaded => {
self.view(ids!(content)).set_visible(cx, true);
self.view(ids!(loading_overlay)).set_visible(cx, false);
self.view(ids!(error_view)).set_visible(cx, false);
}
LoadingState::Loading => {
self.view(ids!(content)).set_visible(cx, true);
self.view(ids!(loading_overlay)).set_visible(cx, true);
self.view(ids!(error_view)).set_visible(cx, false);
}
LoadingState::Error(msg) => {
self.view(ids!(content)).set_visible(cx, false);
self.view(ids!(loading_overlay)).set_visible(cx, false);
self.view(ids!(error_view)).set_visible(cx, true);
self.label(ids!(error_view.error_label)).set_text(cx, msg);
}
}
self.redraw(cx);
}
}
PortalList Item Pattern
For virtual list items:
live_design! {
pub ItemsList = {{ItemsList}} {
list = <PortalList> {
keep_invisible: false,
auto_tail: false,
width: Fill, height: Fill,
flow: Down,
// Item templates
item_entry = <ItemEntry> {}
header = <SectionHeader> {}
empty = <View> {}
}
}
}
impl Widget for ItemsList {
fn draw_walk(&mut self, cx: &mut Cx2d, scope: &mut Scope, walk: Walk) -> DrawStep {
while let Some(item) = self.view.draw_walk(cx, scope, walk).step() {
if let Some(mut list) = item.as_portal_list().borrow_mut() {
list.set_item_range(cx, 0, self.items.len());
while let Some(item_id) = list.next_visible_item(cx) {
let item = list.item(cx, item_id, live_id!(item_entry));
// Populate item with data
self.populate_item(cx, item, &self.items[item_id]);
item.draw_all(cx, scope);
}
}
}
DrawStep::done()
}
}
Best Practices
- Use
#[deref]for delegation: Delegate to inner View for standard behavior - Separate DSL properties (
#[live]) from Rust state (#[rust]) - Implement both inner methods and
*Refwrappers - Use
apply_overfor dynamic runtime styling - Use
flow: Overlayfor toggle/swap patterns - Use
set_visible()to toggle between alternative views - Always call
redraw(cx)after state changes
Reference Files
references/widget-patterns.md- Additional widget patterns (Robrix)references/styling-patterns.md- Dynamic styling patterns (Robrix)references/moly-widget-patterns.md- Moly-specific patternsSlotwidget for runtime content replacementMolyRootconditional rendering wrapperAdaptiveViewfor responsive Mobile/Desktop layouts- Chat line variants (UserLine, BotLine, ErrorLine, etc.)
CommandTextInputwith action buttons- Sidebar navigation with radio buttons