add swiftUI code

iOS-SwiftUI-Code/GRDB.swift-6.29.3/GRDB/Core/DatabaseBackupProgress.swift

@@ -0,0 +1,27 @@
+/// Describe the progress of a database backup.
+///
+/// Related SQLite documentation: <https://www.sqlite.org/c3ref/backup_finish.html>
+public struct DatabaseBackupProgress: Sendable {
+    /// The number of pages still to be backed up.
+    ///
+    /// It is the result of the `sqlite3_backup_remaining` function.
+    public let remainingPageCount: Int
+    
+    /// The number of pages in the source database.
+    ///
+    /// It is the result of the `sqlite3_backup_pagecount` function.
+    public let totalPageCount: Int
+    
+    /// The number of of backed up pages.
+    ///
+    /// It is equal to `totalPageCount - remainingPageCount`.
+    public var completedPageCount: Int {
+        totalPageCount - remainingPageCount
+    }
+    
+    /// A boolean value indicating whether the backup is complete.
+    ///
+    /// It is true if and only if the last call the `sqlite3_backup_step` has
+    /// returned `SQLITE_DONE`.
+    public let isCompleted: Bool
+}