【SwiftUI模块】0060、SwiftUI基于Firebase搭建一个类似InstagramApp 3/7部分-搭建TabBar

SwiftUI模块系列 - 已更新60篇
SwiftUI项目 - 已更新5个项目
往期Demo源码下载

技术:SwiftUI、SwiftUI4.0、Instagram、Firebase
运行环境:
SwiftUI4.0 + Xcode14 + MacOS12.6 + iPhone Simulator iPhone 14 Pro Max

概述

使用SwiftUI基于Firebase搭建一个类似InstagramApp 3/7部分-搭建TabBar - 效果

详细

一、运行效果

二、项目结构图

三、程序实现 - 过程

思路:
1.创建头部模块 进行测试上下滚动拥有放大缩小效果
2.搭建分类模块 固定在头部下面
3.搭建列表模块
4.监听滚动偏移的操作

1.创建一个项目命名为 SpotifyResponvieUI

1.1.引入资源文件和颜色

颜色
BG #281A1A
Green #4DD037
随机图片9张
个人大图背景1张
logo1张

2. 创建一个虚拟文件New Group 命名为 View

3. 创建一个虚拟文件New Group 命名为 Model

4. 创建一个文件New File 选择SwiftUI View类型 命名为Album 并且继承Identifiable

5. 创建一个文件New File 选择SwiftUI View类型 命名为Home

主要是:

6. 创建一个文件New File 选择SwiftUI View类型 命名为OffsetModifier

Code

ContentView - 主窗口

主要是展示主窗口Home和设置暗黑模式

import SwiftUI

struct ContentView: View {
    var body: some View {
        Home()
        // 永远是黑暗模式
            .preferredColorScheme(.dark)
    }
    
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16

Home - 主页

思路

1. 主要就是展示大图背景 + 固定的分类 + 列表模块

//
//  Home.swift
//  SpotifyResponvieUI (iOS)
//
//  Created by lyh on 2022/8/23.
//

import SwiftUI

struct Home: View {
    @State var currentType: String = "Popular"
    // 光滑滑动效果
    @Namespace var animation
    @State var _albums: [Album] = albums
    
    // x,y
    @State var headerOffsets: (CGFloat,CGFloat) = (0,0)
    
    var body: some View {
        ScrollView(.vertical, showsIndicators: false) {
            VStack(spacing: 0){
                HeaderView()
                // 带内容的固定标题
                LazyVStack(pinnedViews: [.sectionHeaders]) {
                    Section {
                        SongList()
                    } header: {
                        PinnedHeaderView()
                            .background(Color.black)
                            .offset(y: headerOffsets.1 > 0 ? 0 : -headerOffsets.1 / 8)
                            .modifier(OffsetModifier(offset: $headerOffsets.0, returnFromStart: false))
                            .modifier(OffsetModifier(offset: $headerOffsets.1))
                    }
                }
            }
        }
        .overlay(content: {
            Rectangle()
                .fill(.black)
                .frame(height: 50)
                .frame(maxHeight: .infinity,alignment: .top)
                .opacity(headerOffsets.0 < 5 ? 1 : 0)
        })
        .coordinateSpace(name: "SCROLL")
        .ignoresSafeArea(.container, edges: .vertical)
    }
    
    // 固定的内容
    @ViewBuilder
    func SongList()->some View{
        VStack(spacing: 25){
            ForEach($_albums){$album in
                
                HStack(spacing: 12){
                    
                    Text("#\(getIndex(album: album) + 1)")
                        .fontWeight(.semibold)
                        .foregroundColor(.gray)
                    
                    Image(album.albumImage)
                        .resizable()
                        .aspectRatio(contentMode: .fill)
                        .frame(width: 55, height: 55)
                        .clipShape(RoundedRectangle(cornerRadius: 10, style: .continuous))
                    
                    VStack(alignment: .leading, spacing: 8) {
                        Text(album.albumName)
                            .fontWeight(.semibold)
                        
                        Label {
                            Text("65,587,909")
                        } icon: {
                            Image(systemName: "beats.headphones")
                                .foregroundColor(.white)
                        }
                        .foregroundColor(.gray)
                        .font(.caption)
                    }
                    .frame(maxWidth: .infinity,alignment: .leading)
                    
                    Button {
                        album.isLiked.toggle()
                    } label: {
                     
                        Image(systemName: album.isLiked ? "suit.heart.fill" : "suit.heart")
                            .font(.title3)
                            .foregroundColor(album.isLiked ? Color("Green") : .white)
                    }
                    
                    Button {
                    } label: {
                     
                        Image(systemName: "ellipsis")
                            .font(.title3)
                            .foregroundColor(.white)
                    }
                }
            }
        }
        .padding()
        .padding(.top,25)
        .padding(.bottom,150)
    }
    
    func getIndex(album: Album)->Int{
        return _albums.firstIndex { currentAlbum in
            return album.id == currentAlbum.id
        } ?? 0
    }
    
    // 头部视图
    @ViewBuilder
    func HeaderView()->some View{
        GeometryReader{proxy in
            let minY = proxy.frame(in: .named("SCROLL")).minY
            let size = proxy.size
            let height = (size.height + minY)
            
            Image("Ariana")
                .resizable()
                .aspectRatio(contentMode: .fill)
                .frame(width: size.width,height: height > 0 ? height : 0,alignment: .top)
                .overlay(content: {
                    ZStack(alignment: .bottom) {
                        
                        // 调暗文本内容
                        LinearGradient(colors: [
                            .clear,
                            .black.opacity(0.8)
                        ], startPoint: .top, endPoint: .bottom)
                        
                        VStack(alignment: .leading, spacing: 12) {
                            
                            Text("宇夜iOS")
                                .font(.callout)
                                .foregroundColor(.gray)
                            
                            HStack(alignment: .bottom, spacing: 10) {
                                Text("Ariana Grande")
                                    .font(.title.bold())
                                
                                Image(systemName: "checkmark.seal.fill")
                                    .foregroundColor(.blue)
                                    .background{
                                        Circle()
                                            .fill(.white)
                                            .padding(3)
                                    }
                            }
                            
                            Label {
                             
                                Text("Monthly Listeners")
                                    .fontWeight(.semibold)
                                    .foregroundColor(.white.opacity(0.7))
                            } icon: {
                                Text("62,354,659")
                                    .fontWeight(.semibold)
                            }
                            .font(.caption)
                        }
                        .padding(.horizontal)
                        .padding(.bottom,25)
                        .frame(maxWidth: .infinity,alignment: .leading)
                    }
                })
                .cornerRadius(15)
                .offset(y: -minY)
        }
        .frame(height: 250)
    }
    
    // 固定在头部
    @ViewBuilder
    func PinnedHeaderView()->some View{
        let types: [String] = ["Popular","Albums","Songs","Fans also like","About"]
        ScrollView(.horizontal, showsIndicators: false) {
            HStack(spacing: 25){
                
                ForEach(types,id: \.self){type in
                    VStack(spacing: 12){
                        
                        Text(type)
                            .fontWeight(.semibold)
                            .foregroundColor(currentType == type ? .white : .gray)
                        
                        ZStack{
                            if currentType == type{
                                RoundedRectangle(cornerRadius: 4, style: .continuous)
                                    .fill(.white)
                                    .matchedGeometryEffect(id: "TAB", in: animation)
                            }
                            else{
                                RoundedRectangle(cornerRadius: 4, style: .continuous)
                                    .fill(.clear)
                            }
                        }
                        .padding(.horizontal,8)
                        .frame(height: 4)
                    }
                    .contentShape(Rectangle())
                    .onTapGesture {
                        withAnimation(.easeInOut){
                            currentType = type
                        }
                    }
                }
            }
            .padding(.horizontal)
            .padding(.top,25)
            .padding(.bottom,5)
        }
    }
}

struct Home_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221

OffsetModifier - 主要是监听ScrollView的滚动

用来监听ScrollView的滚动 偏移量的改变

//
//  OffsetModifier.swift
//  SpotifyResponvieUI (iOS)
//
//  Created by lyh on 2022/8/23.
//

import SwiftUI

// 继承于 ViewModifier 最主要是能方便扩展一些常见的设置属性
/*
 比如 给Text设置字体\背景颜色\阴影效果
 extension Text {
     func songStyle() -> some View {
         self
             .font(.system(size: 24, weight: .bold))
             .foregroundColor(.white)
             .shadow(radius: 20)
     }
 }
 
 ⭐️如果是继承ViewModifier
 struct SongTextViewModifier: ViewModifier {
     func body(content: Content) -> some View {
         content
           .font(.system(size: 24, weight: .bold))
           .foregroundColor(.white)
           .shadow(radius: 20)
     }
 }

 然后直接通过
 
 Text(song)
       .modifier(SongTextViewModifier())
 设置
 */

struct OffsetModifier: ViewModifier {
    @Binding var offset: CGFloat
    
    // 可选从0返回值
    var returnFromStart: Bool = true
    @State var startValue: CGFloat = 0
    
    func body(content: Content) -> some View {
        content
            .overlay {
                GeometryReader{proxy in
                    Color.clear
                        .preference(key: OffsetKey.self, value: proxy.frame(in: .named("SCROLL")).minY)
                        .onPreferenceChange(OffsetKey.self) { value in
                            if startValue == 0{
                                startValue = value
                            }
                            print(value);

                            offset = (value - (returnFromStart ? startValue : 0))
                            
                            print("offset is \(offset)");

                        }
                }
            }
    }
}

// 偏好的关键
struct OffsetKey: PreferenceKey{
    static var defaultValue: CGFloat = 0
    
    static func reduce(value: inout CGFloat, nextValue: () -> CGFloat) {
        value = nextValue()
    }
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76

Album - 模型

//
//  Album.swift
//  SpotifyResponvieUI (iOS)
//
//  Created by lyh on 2022/8/23.
//

import SwiftUI

// Ablum模型和样本数据
struct Album: Identifiable {
    var id = UUID().uuidString
    var albumName: String
    var albumImage : String
    var isLiked : Bool = false
}


var albums : [Album] = [
    
    Album(albumName: "Positions", albumImage: "Album1"),
    Album(albumName: "The Best", albumImage: "Album2",isLiked: true),
    Album(albumName: "My Everything", albumImage: "Album3"),
    Album(albumName: "Yours Truly", albumImage: "Album4"),
    Album(albumName: "Sweetener", albumImage: "Album5",isLiked: true),
    Album(albumName: "Rain On Me", albumImage: "Album6"),
    Album(albumName: "Stuck With U", albumImage: "Album7"),
    Album(albumName: "7 rings", albumImage: "Album8",isLiked: true),
    Album(albumName: "Bang Bang", albumImage: "Album9"),
    
]

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32