gpui-event▌

Overview

GPUI provides event system for component coordination:

Event Mechanisms:

• Custom Events: Define and emit type-safe events
• Observations: React to entity state changes
• Subscriptions: Listen to events from other entities
• Global Events: App-wide event handling

Quick Start

Define and Emit Events

#[derive(Clone)]
enum MyEvent {
    DataUpdated(String),
    ActionTriggered,
}

impl MyComponent {
    fn update_data(&mut self, data: String, cx: &mut Context<Self>) {
        self.data = data.clone();

        // Emit event
        cx.emit(MyEvent::DataUpdated(data));
        cx.notify();
    }
}

Subscribe to Events

impl Listener {
    fn new(source: Entity<MyComponent>, cx: &mut App) -> Entity<Self> {
        cx.new(|cx| {
            // Subscribe to events
            cx.subscribe(&source, |this, emitter, event: &MyEvent, cx| {
                match event {
                    MyEvent::DataUpdated(data) => {
                        this.handle_update(data.clone(), cx);
                    }
                    MyEvent::ActionTriggered => {
                        this.handle_action(cx);
                    }
                }
            }).detach();

            Self { source }
        })
    }
}

Observe Entity Changes

impl Observer {
    fn new(target: Entity<Target>, cx: &mut App) -> Entity<Self> {
        cx.new(|cx| {
            // Observe entity for any changes
            cx.observe(&target, |this, observed, cx| {
                // Called when observed.update() calls cx.notify()
                println!("Target changed");
                cx.notify();
            }).detach();

            Self { target }
        })
    }
}

Common Patterns

1. Parent-Child Communication

// Parent emits events
impl Parent {
    fn notify_children(&mut self, cx: &mut Context<Self>) {
        cx.emit(ParentEvent::Updated);
        cx.notify();
    }
}

// Children subscribe
impl Child {
    fn new(parent: Entity<Parent>, cx: &mut App) -> Entity<Self> {
        cx.new(|cx| {
            cx.subscribe(&parent, |this, parent, event, cx| {
                this.handle_parent_event(event, cx);
            }).detach();

            Self { parent }
        })
    }
}

2. Global Event Broadcasting

struct EventBus {
    listeners: Vec<WeakEntity<dyn Listener>>,
}

impl EventBus {
    fn broadcast(&mut self, event: GlobalEvent, cx: &mut Context<Self>) {
        self.listeners.retain(|weak| {
            weak.update(cx, |listener, cx| {
                listener.on_event(&event, cx);
            }).is_ok()
        });
    }
}

3. Observer Pattern

cx.observe(&entity, |this, observed, cx| {
    // React to any state change
    let state = observed.read(cx);
    this.sync_with_state(state, cx);
}).detach();

Best Practices

✅ Detach Subscriptions

// ✅ Detach to keep alive
cx.subscribe(&entity, |this, source, event, cx| {
    // Handle event
}).detach();

✅ Clean Event Types

how to use gpui-event
CursorClaude CodeClineCodexWindsurfGooseGitHub CopilotVS CodeGemini CLIKiloOpencodeKimi CLIRoo ClineAiderContinueZedBolt.newLovablev0Replit AgentSweepSmol DeveloperDevinCavemanAmpAntigravity
How to use gpui-event on Cursor
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1
Prerequisites
Before installing skills in Cursor, ensure your development environment meets these requirements:
›Cursor installed and configured on your development machine
›Node.js version 16.0+ with npm package manager (verify with node --version)
›Active project directory or workspace where you want to add gpui-event
2
Execute installation command
Execute the skills CLI command in your project's root directory to begin installation:
$npx skills add https://github.com/longbridge/gpui-component --skill gpui-eventcopy
The skills CLI fetches gpui-event from GitHub repository longbridge/gpui-component and configures it for Cursor.
3
Select Cursor when prompted
The CLI will show a list of available agents. Use arrow keys to navigate and space to select Cursor:
◆ Which agents do you want to install to?
│
│ ── Universal (.agents/skills) ── always included ────
│   • Amp
│   • Antigravity
│   • Cline
│   • Codex
│ ●Cursor(selected)
│   • Cursor
│   • Windsurf
4
Verify installation
Confirm successful installation by checking the skill directory location:
.cursor/skills/gpui-event
Reload or restart Cursor to activate gpui-event. Access the skill through slash commands (e.g., /gpui-event) or your agent's skill management interface.
⚠
Security & Verification Notice
We perform automated surface-level scans (Gen AI Scanner, Socket, Snyk) during installation. These checks detect common vulnerabilities but do not guarantee complete security. Always review skill source code and verify the publisher's reputation before production use.
Skills execute code in your development environment. Always verify the publisher's identity, review recent commits, and test in isolated environments before production deployment.
Additional Resources
›View source code on GitHub›Skills CLI documentation›Learn more about Cursor›What are agent skills?