element-ios/RiotSwiftUI/Modules/Common/ViewFrameReader/ViewFrameReader.swift

34 lines
860 B
Swift

//
// Copyright 2021-2024 New Vector Ltd.
//
// SPDX-License-Identifier: AGPL-3.0-only
// Please see LICENSE in the repository root for full details.
//
import Foundation
import SwiftUI
/// Used to calculate the frame of a view.
///
/// Useful in situations as with `ZStack` where you might want to layout views using alignment guides.
/// ```
/// @State private var frame: CGRect = CGRect.zero
/// ...
/// SomeView()
/// .background(ViewFrameReader(frame: $frame))
/// ```
struct ViewFrameReader: View {
@Binding var frame: CGRect
var body: some View {
GeometryReader { geometry in
Color.clear
.preference(key: FramePreferenceKey.self,
value: geometry.frame(in: .local))
}
.onPreferenceChange(FramePreferenceKey.self) {
frame = $0
}
}
}