BottomSplitView

A SwiftUI-friendly bottom split view for macOS apps. BottomSplitView gives you a primary content area, a resizable bottom panel, and a status bar that remains visible when the panel is collapsed.

The package is useful for editor-style interfaces, consoles, inspectors, logs, timelines, and any macOS UI where a secondary panel should slide between collapsed and expanded states without losing the bottom status controls.

Preview

Requirements

• macOS 14 or later
• Swift 6
• SwiftUI

Installation

Add this package to your app with Swift Package Manager.

In Xcode:

1. Open your app project.
2. Select File > Add Package Dependencies....
3. Enter the repository URL for this package.
4. Add the BottomSplitView product to your macOS app target.

Or add it to another Swift package:

dependencies: [
    .package(url: "https://github.com/chatoutsidis/BottomSplitView.git", from: "0.1.0")
]

Then add BottomSplitView to the target that uses it:

.target(
    name: "YourApp",
    dependencies: ["BottomSplitView"]
)

Basic Usage

Import the package and bind the panel presentation state from your SwiftUI view.

import SwiftUI
import BottomSplitView

struct ContentView: View {
    @State private var isPanelPresented = true

    var body: some View {
        BottomSplitView(
            isPanelPresented: $isPanelPresented,
            defaultPanelHeight: 220,
            minPanelHeight: 140,
            maxPanelHeight: .greatestFiniteMagnitude
        ) {
            mainContent
        } panel: {
            bottomPanel
        } statusBar: {
            statusBar
        }
        .frame(minWidth: 700, minHeight: 450)
    }

    private var mainContent: some View {
        Text("Primary content")
            .frame(maxWidth: .infinity, maxHeight: .infinity)
    }

    private var bottomPanel: some View {
        Text("Bottom panel")
            .frame(maxWidth: .infinity, maxHeight: .infinity)
            .background(Color.black.opacity(0.08))
    }

    private var statusBar: some View {
        HStack {
            Text("Status")
            Spacer()
            Button(isPanelPresented ? "Hide" : "Show") {
                isPanelPresented.toggle()
            }
        }
        .padding(.horizontal, 12)
        .frame(maxWidth: .infinity, maxHeight: .infinity)
        .background(Color(NSColor.windowBackgroundColor))
    }
}

How It Works

BottomSplitView renders three SwiftUI areas:

• primary: the main content above the divider.
• panel: the expandable content in the bottom split area.
• statusBar: the always-visible bottom strip.

When isPanelPresented is true, the bottom area contains the panel plus the status bar. When it is false, the panel collapses and only the status bar remains visible.

Users can drag the divider to resize the panel. If they drag the panel below the collapse snap threshold and release, the panel collapses and the binding is updated to false. Expanding again restores the most recent expanded panel height, clamped to the configured limits.

Configuration

BottomSplitView(
    isPanelPresented: $isPanelPresented,
    defaultPanelHeight: 220,
    minPanelHeight: 140,
    maxPanelHeight: 500,
    statusBarHeight: 32,
    collapseSnapThreshold: 90,
    dividerHitExtension: 10
) {
    // Primary content
} panel: {
    // Bottom panel
} statusBar: {
    // Status bar
}

Parameter	Description
isPanelPresented	A binding that controls whether the bottom panel is expanded. The component also updates this binding when the user collapses or expands by dragging.
defaultPanelHeight	The initial expanded panel height, excluding the status bar.
minPanelHeight	The minimum expanded panel height.
maxPanelHeight	The maximum expanded panel height. Use .greatestFiniteMagnitude to let available window height decide the limit.
statusBarHeight	The fixed height of the status bar. Defaults to 32.
collapseSnapThreshold	If the panel is dragged below this height and released, it collapses. Defaults to 90.
dividerHitExtension	Extra interactive height added around the divider to make resizing easier. Defaults to 10.

Demo App

A small example app is included in Examples/DemoApp. Open the demo project in Xcode to see BottomSplitView wired into a SwiftUI macOS app.

Development

Run the package tests from the repository root:

swift test