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@mecid
Last active July 19, 2024 13:44
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PagerView in SwiftUI
//
// PagerView.swift
//
// Created by Majid Jabrayilov on 12/5/19.
// Copyright © 2019 Majid Jabrayilov. All rights reserved.
//
import SwiftUI
struct PagerView<Content: View>: View {
let pageCount: Int
@Binding var currentIndex: Int
let content: Content
@GestureState private var translation: CGFloat = 0
init(pageCount: Int, currentIndex: Binding<Int>, @ViewBuilder content: () -> Content) {
self.pageCount = pageCount
self._currentIndex = currentIndex
self.content = content()
}
var body: some View {
GeometryReader { geometry in
HStack(spacing: 0) {
self.content.frame(width: geometry.size.width)
}
.frame(width: geometry.size.width, alignment: .leading)
.offset(x: -CGFloat(self.currentIndex) * geometry.size.width)
.offset(x: self.translation)
.animation(.interactiveSpring())
.gesture(
DragGesture().updating(self.$translation) { value, state, _ in
state = value.translation.width
}.onEnded { value in
let offset = value.translation.width / geometry.size.width
let newIndex = (CGFloat(self.currentIndex) - offset).rounded()
self.currentIndex = min(max(Int(newIndex), 0), self.pageCount - 1)
}
)
}
}
}
@samilao101
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Is there any way to load the views lazily?

@mecid
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mecid commented May 5, 2022

@samilao101 did you try to use LazyHStack instead of HStack?

@samilao101
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@mecid I did, but the issue is that in order for a lazyhstack to become lazy it needs to be imbedded in a scrollview, and if you do that, you essentially lose the pagination feature.

@mecid
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mecid commented May 5, 2022

@samilao101 oh, you're right. Maybe TabView with Page style will work for you better?

@pjcau
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pjcau commented May 30, 2022

So isn't the lazy this approach....Load all contents and onAppear

@samilao101
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@pjcau sorry I am not sure I understand what you mean

@pjcau
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pjcau commented May 30, 2022

@pjcau sorry I am not sure I understand what you mean

IN this way, if you want load a array of DetalView for example, so load in one step all init and onAppear(). So it's not good. But fix it with TabView with Page style.

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ghost commented Sep 27, 2022

@pjcau did you manage to integrate ScrollView in order to achieve lazy loading?

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