Resizable

Panel groups and resize handles for user-adjustable split layouts.

Like every gpui-base primitive, Resizable supplies behavior and semantic structure without imposing a product visual language. Apply GPUI styles and compose the exported parts to match your design system.

#Example

The single native Cargo entrypoint selects this primitive from the shared showcase implementation. The same showcase is compiled once for the WASM preview above.

cargo run -p gpui-base-examples -- resizable

#Import

use gpui_kit::base::{ResizablePanel, ResizablePanelGroup, ResizableState, h_resizable, resizable_panel};

#Anatomy and API

The example composes ResizablePanel, ResizablePanelGroup, ResizableState. GPUI’s standard styling and event traits provide presentation; these base types provide the interaction structure.

The authoritative module is components/resizable.rs. Native and browser previews compile this same file.

#State and events

Panel sizes live in resizable state; dragging handles updates adjacent panels subject to minimums.

Keep controlled state on the parent render type or in a GPUI entity. Update it in callbacks and call cx.notify(); do not recreate persistent entities during every render.

#Handle appearance

Base owns a handle’s hit band, its cursor and the drag; what is painted inside it is the consumer’s. ResizeHandleRenderer is handed a ResizeHandleContext carrying the axis and a ResizeHandleState — Idle, Hovered, Pressed or Dragging. The last two are tracked by base because a drag takes the pointer out of the nine-pixel band almost at once, so GPUI’s hover reads false for most of a drag.

Returning None keeps base’s own one-pixel line, so a renderer can override some handles and leave the rest alone.

#Complete Rust example

The complete implementation used by the runnable showcase is embedded directly from Rust source:

use gpui::{IntoElement, ParentElement as _, Styled as _, div, px};
use gpui_base::{h_resizable, resizable_panel};

use super::super::BaseShowcase;

impl BaseShowcase {
    pub(in super::super) fn resizable(&self) -> impl IntoElement {
        div()
            .w_72()
            .h_40()
            .text_xs()
            .border_1()
            .border_color(super::example_rgb(0x171717))
            .child(
                h_resizable("example-resizable")
                    .child(
                        resizable_panel()
                            .size(px(124.))
                            .size_range(px(116.)..px(210.))
                            .child(
                                div()
                                    .size_full()
                                    .flex()
                                    .items_center()
                                    .justify_center()
                                    .border_r_1()
                                    .border_color(super::example_rgb(0x171717))
                                    .p_2()
                                    .items_start()
                                    .justify_start()
                                    .flex_col()
                                    .gap_1()
                                    .child(
                                        div()
                                            .text_xs()
                                            .text_color(super::example_rgb(0x737373))
                                            .child("PROJECT"),
                                    )
                                    .children(["Overview", "Components", "Settings"].map(
                                        |label| {
                                            div()
                                                .w_full()
                                                .h(px(26.))
                                                .px_2()
                                                .flex()
                                                .items_center()
                                                .whitespace_nowrap()
                                                .child(label)
                                        },
                                    )),
                            ),
                    )
                    .child(
                        resizable_panel().child(
                            div()
                                .size_full()
                                .flex()
                                .items_center()
                                .justify_center()
                                .bg(super::example_rgb(0xffffff))
                                .p_2()
                                .items_start()
                                .justify_start()
                                .flex_col()
                                .gap_2()
                                .child(div().child("Workspace"))
                                .child(
                                    div()
                                        .text_color(super::example_rgb(0x737373))
                                        .child("Drag the divider to resize navigation."),
                                ),
                        ),
                    ),
            )
    }
}

The command above supplies application initialization, window creation, and shared BaseShowcase state.

#Accessibility

Provide keyboard alternatives for handles and preserve usable minimum panel sizes.

#Notes

Use stable element IDs where accepted. Verify focus, hover, active, selected, disabled, reduced-motion, and high-contrast appearances in the consuming design system.