[ADD] Backported dismiss() environment variable to let views dismiss themselves

AltStore/View Extensions/EnvironmentValues.swift

@@ -0,0 +1,16 @@
+//
+//  EnvironmentValues.swift
+//  SideStore
+//
+//  Created by Fabian Thies on 29.11.22.
+//  Copyright © 2022 SideStore. All rights reserved.
+//
+
+import SwiftUI
+
+@available(iOS 14.0, *)
+extension EnvironmentValues {
+    var dismiss: () -> Void {
+        { presentationMode.wrappedValue.dismiss() }
+    }
+}

AltStore/Views/Browse/ConfirmAddSourceView.swift

@@ -65,18 +65,8 @@ struct ConfirmAddSourceView: View {
                 confirmationHandler(fetchedSource)
             } label: {
                 Label(title: { Text("Add Source") }, icon: { Image(systemName: "plus") })
-                    .multilineTextAlignment(.center)
-                    .foregroundColor(.white)
-                    .padding()
-                    .frame(
-                        maxWidth: .infinity,
-                        alignment: .bottomLeading
-                    )
-                    .background(
-                        RoundedRectangle(cornerRadius: 10)
-                            .foregroundColor(Color.accentColor)
-                    )
             }
+            .buttonStyle(FilledButtonStyle())
             .padding()
         }
         .background(Color(UIColor.systemGroupedBackground).ignoresSafeArea())

AltStore/Views/Browse/SourcesView.swift

@@ -12,6 +12,9 @@ import CoreData
 
 struct SourcesView: View {
     
+    @Environment(\.dismiss)
+    private var dismiss
+    
     @Environment(\.managedObjectContext)
     var managedObjectContext
     
@@ -102,9 +105,7 @@ struct SourcesView: View {
             }
             
             ToolbarItem(placement: .navigationBarTrailing) {
-                SwiftUI.Button {
+                SwiftUI.Button(action: self.dismiss) {
-                    self.isShowingAddSourceAlert = false
-                } label: {
                     Text("Done").bold()
                 }
             }