{"id":6924,"date":"2025-11-30T16:38:48","date_gmt":"2025-11-30T08:38:48","guid":{"rendered":"https:\/\/t.n-years.com\/?p=6924"},"modified":"2025-11-30T16:38:48","modified_gmt":"2025-11-30T08:38:48","slug":"swiftui-%e4%b8%ad%e7%9a%84-%e5%b1%9e%e6%80%a7%e5%8c%85%e8%a3%85%e5%99%a8","status":"publish","type":"post","link":"https:\/\/t.n-years.com\/?p=6924","title":{"rendered":"SwiftUI \u4e2d\u7684 \u5c5e\u6027\u5305\u88c5\u5668"},"content":{"rendered":"<p>SwiftUI \u4e2d\u7684\u8fd9\u4e9b\u6ce8\u89e3\uff08\u4e13\u4e1a\u672f\u8bed\u53eb <strong>Property Wrappers \/ \u5c5e\u6027\u5305\u88c5\u5668<\/strong>\uff09\u662f\u9a71\u52a8\u754c\u9762\u5237\u65b0\u7684\u6838\u5fc3\u5f15\u64ce\u3002<\/p>\n<p>\u4f60\u53ef\u4ee5\u628a\u5b83\u4eec\u7b80\u5355\u7406\u89e3\u4e3a\uff1a<strong>\u544a\u8bc9 SwiftUI \u67d0\u4e2a\u53d8\u91cf\u7684\u201c\u8eab\u4efd\u201d\u548c\u201c\u5237\u65b0\u89c4\u5219\u201d\u3002<\/strong><\/p>\n<p>\u4e3a\u4e86\u65b9\u4fbf\u8bb0\u5fc6\uff0c\u6211\u628a\u5b83\u4eec\u5206\u4e3a\u4e09\u5927\u7c7b\uff1a<strong>\u57fa\u7840\u503c\u7c7b\u578b<\/strong>\u3001<strong>\u5f15\u7528\u7c7b\u578b\uff08\u5bf9\u8c61\uff09<\/strong>\u3001<strong>\u73af\u5883\u4e0e\u5b58\u50a8<\/strong>\u3002<\/p>\n<hr \/>\n<h3>\u7b2c\u4e00\u7c7b\uff1a\u57fa\u7840\u503c\u7c7b\u578b (Int, String, Bool, Struct)<\/h3>\n<p>\u7528\u4e8e\u7ba1\u7406\u7b80\u5355\u7684 UI \u72b6\u6001\uff0c\u6bd4\u5982\u5f00\u5173\u3001\u8f93\u5165\u6846\u6587\u5b57\u3001\u6570\u5b57\u8ba1\u6570\u3002<\/p>\n<h4>1. <code>@State<\/code> (\u79c1\u6709\u72b6\u6001)<\/h4>\n<ul>\n<li><strong>\u8eab\u4efd\uff1a<\/strong> <strong>\u201c\u623f\u4e3b\u201d<\/strong>\u3002<\/li>\n<li><strong>\u4f5c\u7528\uff1a<\/strong> View \u5185\u90e8\u79c1\u6709\u7684\u3001\u7531 View \u81ea\u5df1\u521b\u5efa\u548c\u7ba1\u7406\u7684\u53d8\u91cf\u3002<\/li>\n<li><strong>\u5237\u65b0\u89c4\u5219\uff1a<\/strong> \u503c\u6539\u53d8 -> <strong>\u5f53\u524d View<\/strong> \u91cd\u65b0\u6e32\u67d3\u3002<\/li>\n<li>\n<p><strong>\u573a\u666f\uff1a<\/strong> \u6309\u94ae\u70b9\u51fb\u6b21\u6570\u3001\u5f39\u7a97\u662f\u5426\u663e\u793a\u3001\u8f93\u5165\u6846\u7684\u5185\u5bb9\u3002<\/p>\n<pre><code class=\"language-swift\">struct CounterView: View {\n    @State private var count = 0 \/\/ View \u81ea\u5df1\u7ba1\u7406\u8fd9\u4e2a\u72b6\u6001\n\n    var body: some View {\n        Button(\"Tap me: \\(count)\") { count += 1 }\n    }\n}<\/code><\/pre>\n<\/li>\n<\/ul>\n<h4>2. <code>@Binding<\/code> (\u7ed1\u5b9a \/ \u5f15\u7528)<\/h4>\n<ul>\n<li><strong>\u8eab\u4efd\uff1a<\/strong> <strong>\u201c\u4f20\u58f0\u7b52\u201d<\/strong>\u3002<\/li>\n<li><strong>\u4f5c\u7528\uff1a<\/strong> \u5b83\u4e0d\u5b58\u6570\u636e\uff0c\u5b83\u53ea\u662f\u6307\u5411\u522b\u4eba\uff08\u901a\u5e38\u662f\u7236\u89c6\u56fe\uff09\u7684 <code>@State<\/code>\u3002\u5b83\u5b9e\u73b0\u4e86<strong>\u53cc\u5411\u7ed1\u5b9a<\/strong>\uff1a\u5b50\u89c6\u56fe\u6539\u4e86\uff0c\u7236\u89c6\u56fe\u7684\u6570\u636e\u4e5f\u4f1a\u53d8\u3002<\/li>\n<li><strong>\u573a\u666f\uff1a<\/strong> \u5f00\u5173\u7ec4\u4ef6\uff08Toggle\uff09\u3001\u8f93\u5165\u6846\u7ec4\u4ef6\u3002<\/li>\n<li>\n<p><strong>\u7528\u6cd5\uff1a<\/strong> \u4f20\u53c2\u65f6\u9700\u8981\u52a0 <code>$<\/code> \u7b26\u53f7\u3002<\/p>\n<pre><code class=\"language-swift\">struct ParentView: View {\n    @State private var isOn = false\n    var body: some View {\n        \/\/ \u628a $isOn \u4f20\u7ed9\u5b50\u89c6\u56fe\uff0c\u5efa\u7acb\u8fde\u63a5\n        ToggleView(isOn: $isOn) \n    }\n}\n\nstruct ToggleView: View {\n    @Binding var isOn: Bool \/\/ \u63a5\u6536\u8fde\u63a5\uff0c\u4e0d\u8bbe\u521d\u503c\n    var body: some View {\n        Toggle(\"Switch\", isOn: $isOn) \/\/ \u4fee\u6539\u8fd9\u91cc\uff0cParentView \u7684 isOn \u4e5f\u4f1a\u53d8\n    }\n}<\/code><\/pre>\n<\/li>\n<\/ul>\n<hr \/>\n<h3>\u7b2c\u4e8c\u7c7b\uff1a\u5f15\u7528\u7c7b\u578b (Class \/ ViewModel)<\/h3>\n<p>\u7528\u4e8e\u7ba1\u7406\u590d\u6742\u7684\u903b\u8f91\u548c\u6570\u636e\uff0c\u901a\u5e38\u9075\u5faa <code>ObservableObject<\/code> \u534f\u8bae\u3002<\/p>\n<h4>3. <code>@StateObject<\/code> (\u5bf9\u8c61\u6301\u6709\u8005)<\/h4>\n<ul>\n<li><strong>\u8eab\u4efd\uff1a<\/strong> <strong>\u201c\u9489\u5b50\u201d (Owner)<\/strong>\u3002<\/li>\n<li><strong>\u4f5c\u7528\uff1a<\/strong> \u8d1f\u8d23<strong>\u521d\u59cb\u5316<\/strong>\u548c<strong>\u6301\u6709<\/strong>\u4e00\u4e2a ViewModel\u3002\u5373\u4f7f View \u5237\u65b0\uff0c\u8fd9\u4e2a\u5bf9\u8c61\u4e5f\u4e0d\u4f1a\u6b7b\u3002<\/li>\n<li><strong>\u573a\u666f\uff1a<\/strong> \u9875\u9762\u521b\u5efa\u81ea\u5df1\u7684 ViewModel \u65f6\u4f7f\u7528\u3002\n<pre><code class=\"language-swift\">@StateObject var vm = MyViewModel() \/\/ \u2705 \u8fd9\u91cc\u6709 = \u53f7<\/code><\/pre>\n<\/li>\n<\/ul>\n<h4>4. <code>@ObservedObject<\/code> (\u5bf9\u8c61\u89c2\u5bdf\u8005)<\/h4>\n<ul>\n<li><strong>\u8eab\u4efd\uff1a<\/strong> <strong>\u201c\u773c\u955c\u201d (Observer)<\/strong>\u3002<\/li>\n<li><strong>\u4f5c\u7528\uff1a<\/strong> \u89c2\u5bdf\u5916\u90e8\u4f20\u5165\u7684 ViewModel\u3002\u5982\u679c View \u5237\u65b0\uff0c\u5b83\u4e0d\u4fdd\u8bc1\u5bf9\u8c61\u5b58\u6d3b\uff08\u6240\u4ee5\u4e0d\u80fd\u5728\u8fd9\u91cc\u521d\u59cb\u5316\uff09\u3002<\/li>\n<li><strong>\u573a\u666f\uff1a<\/strong> \u5b50\u89c6\u56fe\u63a5\u6536\u7236\u89c6\u56fe\u4f20\u8fdb\u6765\u7684 ViewModel\u3002\n<pre><code class=\"language-swift\">@ObservedObject var vm: MyViewModel \/\/ \u274c \u8fd9\u91cc\u901a\u5e38\u6ca1\u6709 = \u53f7<\/code><\/pre>\n<\/li>\n<\/ul>\n<h4>5. <code>@EnvironmentObject<\/code> (\u5168\u5c40\/\u73af\u5883\u5bf9\u8c61)<\/h4>\n<ul>\n<li><strong>\u8eab\u4efd\uff1a<\/strong> <strong>\u201c\u5e7f\u64ad\u63a5\u6536\u5668\u201d<\/strong>\u3002<\/li>\n<li><strong>\u4f5c\u7528\uff1a<\/strong> \u4e0d\u9700\u8981\u4e00\u5c42\u5c42\u4f20\u53c2\uff0c\u76f4\u63a5\u4ece\u201c\u7a7a\u6c14\u201d\uff08\u73af\u5883\uff09\u91cc\u6293\u53d6\u5bf9\u8c61\u3002\u524d\u63d0\u662f\u7956\u5148\u89c6\u56fe\u5fc5\u987b\u5148\u7528 <code>.environmentObject(vm)<\/code> \u6ce8\u5165\u8fc7\u3002<\/li>\n<li><strong>\u573a\u666f\uff1a<\/strong> \u7528\u6237\u767b\u5f55\u4fe1\u606f\u3001\u5168\u5c40\u4e3b\u9898\u8bbe\u7f6e\u3001\u50cf\u4f60\u7684 <code>SyncSettingsViewModel<\/code> \u8fd9\u79cd\u8de8\u9875\u9762\u5171\u4eab\u7684\u6570\u636e\u3002\n<pre><code class=\"language-swift\">@EnvironmentObject var settings: SyncSettingsViewModel<\/code><\/pre>\n<\/li>\n<\/ul>\n<h4>6. <code>@Published<\/code> (\u53d1\u5e03\u8005)<\/h4>\n<ul>\n<li><strong>\u4f4d\u7f6e\uff1a<\/strong> \u5199\u5728 <code>class<\/code> (ViewModel) \u5185\u90e8\u3002<\/li>\n<li><strong>\u4f5c\u7528\uff1a<\/strong> \u544a\u8bc9\u7cfb\u7edf\uff1a\u201c\u5f53\u8fd9\u4e2a\u5c5e\u6027\u53d8\u5316\u65f6\uff0c\u6240\u6709\u89c2\u5bdf\u6211\u7684 View \u90fd\u8981\u5237\u65b0\u201d\u3002\n<pre><code class=\"language-swift\">class MyViewModel: ObservableObject {\n    @Published var items: [String] = [] \/\/ items \u53d8\u4e86\uff0c\u754c\u9762\u5c31\u53d8\n}<\/code><\/pre>\n<\/li>\n<\/ul>\n<hr \/>\n<h3>\u7b2c\u4e09\u7c7b\uff1a\u6301\u4e45\u5316\u4e0e\u73af\u5883\u7cfb\u7edf<\/h3>\n<h4>7. <code>@AppStorage<\/code> (UserDefaults \u5305\u88c5\u5668)<\/h4>\n<ul>\n<li><strong>\u4f5c\u7528\uff1a<\/strong> \u81ea\u52a8\u8bfb\u5199 <code>UserDefaults<\/code>\u3002\u4fee\u6539\u53d8\u91cf\u4f1a\u81ea\u52a8\u4fdd\u5b58\u5230\u672c\u5730\uff0c\u4e14\u81ea\u52a8\u5237\u65b0 UI\u3002<\/li>\n<li><strong>\u573a\u666f\uff1a<\/strong> \u7b80\u5355\u7684\u8bbe\u7f6e\u9879\uff08\u5982\u4f60\u7684 <code>iCloudEnabled<\/code>\uff09\u3002\n<pre><code class=\"language-swift\">@AppStorage(\"username\") var username: String = \"Guest\"<\/code><\/pre>\n<\/li>\n<\/ul>\n<h4>8. <code>@Environment<\/code> (\u7cfb\u7edf\u73af\u5883\u503c)<\/h4>\n<ul>\n<li><strong>\u4f5c\u7528\uff1a<\/strong> \u8bfb\u53d6\u7cfb\u7edf\u63d0\u4f9b\u7684\u73af\u5883\u53d8\u91cf\u3002<\/li>\n<li><strong>\u573a\u666f\uff1a<\/strong> \u83b7\u53d6\u5f53\u524d\u662f\u6df1\u8272\/\u6d45\u8272\u6a21\u5f0f\u3001\u5173\u95ed\u5f53\u524d\u5f39\u7a97\uff08dismiss\uff09\u3001\u83b7\u53d6\u6838\u5fc3\u6570\u636e\u4e0a\u4e0b\u6587\uff08managedObjectContext\uff09\u3002\n<pre><code class=\"language-swift\">@Environment(\\.colorScheme) var colorScheme\n@Environment(\\.dismiss) var dismiss \/\/ \u8c03\u7528 dismiss() \u5173\u95ed\u9875\u9762<\/code><\/pre>\n<\/li>\n<\/ul>\n<hr \/>\n<h3>\u26a1\ufe0f \u603b\u7ed3\uff1a\u6211\u8be5\u7528\u54ea\u4e2a\uff1f(\u51b3\u7b56\u901f\u67e5\u8868)<\/h3>\n<table>\n<thead>\n<tr>\n<th style=\"text-align: left;\">\u4f60\u7684\u6570\u636e\u7c7b\u578b<\/th>\n<th style=\"text-align: left;\">\u6570\u636e\u6765\u6e90<\/th>\n<th style=\"text-align: left;\">\u63a8\u8350\u6ce8\u89e3<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"text-align: left;\"><strong>Int, Bool, String<\/strong><\/td>\n<td style=\"text-align: left;\">\u5f53\u524d View \u81ea\u5df1\u4ea7\u751f<\/td>\n<td style=\"text-align: left;\"><strong><code>@State<\/code><\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: left;\"><strong>Int, Bool, String<\/strong><\/td>\n<td style=\"text-align: left;\">\u7236 View \u4f20\u4e0b\u6765\u7684\uff0c\u4e14\u9700\u8981\u4fee\u6539<\/td>\n<td style=\"text-align: left;\"><strong><code>@Binding<\/code><\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: left;\"><strong>Int, Bool, String<\/strong><\/td>\n<td style=\"text-align: left;\">\u7236 View \u4f20\u4e0b\u6765\u7684\uff0c<strong>\u53ea\u8bfb<\/strong><\/td>\n<td style=\"text-align: left;\">\u666e\u901a\u53d8\u91cf <code>let<\/code> (\u65e0\u9700\u6ce8\u89e3)<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: left;\"><strong>Object (Class)<\/strong><\/td>\n<td style=\"text-align: left;\">\u5f53\u524d View <strong>\u65b0\u5efa<\/strong> (<code>= ViewModel()<\/code>)<\/td>\n<td style=\"text-align: left;\"><strong><code>@StateObject<\/code><\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: left;\"><strong>Object (Class)<\/strong><\/td>\n<td style=\"text-align: left;\">\u7236 View <strong>\u4f20\u53c2<\/strong> (<code>: ViewModel<\/code>)<\/td>\n<td style=\"text-align: left;\"><strong><code>@ObservedObject<\/code><\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: left;\"><strong>Object (Class)<\/strong><\/td>\n<td style=\"text-align: left;\">\u9694\u4ee3\u4f20\u9012 \/ \u5168\u5c40\u5171\u4eab<\/td>\n<td style=\"text-align: left;\"><strong><code>@EnvironmentObject<\/code><\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: left;\"><strong>\u7b80\u5355\u8bbe\u7f6e<\/strong><\/td>\n<td style=\"text-align: left;\">\u9700\u8981\u5b58\u5230 UserDefaults<\/td>\n<td style=\"text-align: left;\"><strong><code>@AppStorage<\/code><\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>\ud83d\udca1 \u8865\u5145\uff1aiOS 17+ \u7684\u65b0\u53d8\u5316 (Observation \u6846\u67b6)<\/h3>\n<p>\u5982\u679c\u4f60\u5728\u770b\u6700\u65b0\u7684 SwiftUI \u6559\u7a0b\uff08iOS 17+\uff09\uff0c\u4f60\u4f1a\u53d1\u73b0\u4e0a\u9762\u7684\u903b\u8f91\u88ab\u7b80\u5316\u4e86\uff1a<\/p>\n<ul>\n<li>\u4e0d\u518d\u9700\u8981 <code>ObservableObject<\/code> \u548c <code>@Published<\/code>\uff0c\u76f4\u63a5\u7528\u5b8f <code>@Observable<\/code> \u6807\u8bb0 Class\u3002<\/li>\n<li>View \u91cc\u4e0d\u518d\u533a\u5206 StateObject\/ObservedObject\uff0c\u7edf\u4e00\u7528 <strong><code>@State<\/code><\/strong> \u6216\u666e\u901a <code>let\/var<\/code>\u3002<\/li>\n<li>\u8fd9\u79cd\u65b0\u5199\u6cd5\u662f\u672a\u6765\u7684\u8d8b\u52bf\uff0c\u4f46\u76ee\u524d\u4e3a\u4e86\u517c\u5bb9 iOS 16\/15\uff0c\u4e0a\u9762\u7684\u65e7\u5199\u6cd5\u4f9d\u7136\u662f\u4e3b\u6d41\u3002<\/li>\n<\/ul>\n<p>\u4f60\u60f3\u770b\u4e00\u4e2a\u628a\u8fd9\u4e9b\u90fd\u4e32\u8d77\u6765\u7684<strong>\u5b8c\u6574\u4ee3\u7801\u793a\u4f8b<\/strong>\u5417\uff1f<\/p>\n","protected":false},"excerpt":{"rendered":"<p>SwiftUI \u4e2d\u7684\u8fd9\u4e9b\u6ce8\u89e3\uff08\u4e13\u4e1a\u672f\u8bed\u53eb Property Wrappers \/ \u5c5e\u6027\u5305\u88c5\u5668\uff09\u662f\u9a71\u52a8\u754c\u9762\u5237\u65b0\u7684&#8230; <\/p>\n<div class=\"read-more navbutton\"><a href=\"https:\/\/t.n-years.com\/?p=6924\">\u9605\u8bfb\u66f4\u591a<i class=\"fa fa-angle-double-right\"><\/i><\/a><\/div>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[135],"tags":[],"class_list":["post-6924","post","type-post","status-publish","format-standard","hentry","category-135"],"_links":{"self":[{"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/posts\/6924","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/t.n-years.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=6924"}],"version-history":[{"count":1,"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/posts\/6924\/revisions"}],"predecessor-version":[{"id":6925,"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/posts\/6924\/revisions\/6925"}],"wp:attachment":[{"href":"https:\/\/t.n-years.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=6924"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/t.n-years.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=6924"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/t.n-years.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=6924"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}