Download

src/chdTour.App/Components/Pages/Settings.razor

@@ -1,11 +1,14 @@
 @page "/settings"
+@using chdTour.App.Implementations
 @using chdTour.Contracts.Constants
+@using chdTour.Persistence.EF
 @inherits PageComponentBase<int,int>
-
+@inject IDownloadService downloader
 
 
 <ThemeModeButton />
 
+<IconButton FAClass="download" OnClick="this.DownloadDBFile">Save Database File</IconButton>>
 
 
 @code {
@@ -14,4 +17,18 @@
         this.Title = PageTitleConstants.Settings;
         return base.OnInitializedAsync();
     }
+
+    private async Task DownloadDBFile()
+    {
+        var file = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), "chdTour", $"{nameof(chdTourContext)}.db");
+        var file2 = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), "chdTour", $"{nameof(chdTourContext)}_bak.db");
+
+        File.Copy(file, file2, true);
+
+        using Stream fs = File.OpenRead(file2);
+        using MemoryStream ms = new MemoryStream();
+        await fs.CopyToAsync(ms);
+        await downloader.DownloadFileFromStream("db.db", ms.ToArray());
+    }
+
 }

src/chdTour.App/Extensions/DIExtensions.cs

@@ -24,6 +24,7 @@ public static IServiceCollection AddUI(this IServiceCollection services, IConfig
 
             services.AddMauiModalHandler();
 
+            services.AddTransient<IDownloadService, DownloadService>();
             services.AddTransient<ICustomFilePicker, CustomFilePicker>();
 
             services.AddSingleton<IVibrationHelper, VibrationHelper>();

src/chdTour.App/Implementations/DownloadService.cs

@@ -0,0 +1,38 @@
+using Microsoft.JSInterop;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace chdTour.App.Implementations
+{
+    public class DownloadService : IDownloadService
+    {
+        private readonly IJSRuntime _jSRuntime;
+
+        public DownloadService(IJSRuntime jSRuntime)
+        {
+            this._jSRuntime = jSRuntime;
+        }
+
+        public async Task DownloadFileFromStream(string name, byte[] data)
+        {
+            var fileStream = GetFileStream(data);
+            var fileName = name;
+
+            using var streamRef = new DotNetStreamReference(stream: fileStream);
+            await this._jSRuntime.InvokeVoidAsync("downloadFileFromStream", fileName, streamRef);
+        }
+
+        private Stream GetFileStream(byte[] data)
+        {
+            var fileStream = new MemoryStream(data);
+            return fileStream;
+        }
+    }
+    public interface IDownloadService
+    {
+        Task DownloadFileFromStream(string name, byte[] data);
+    }
+}

src/chdTour.App/MainPage.xaml.cs

@@ -1,9 +1,12 @@
 #if ANDROID
+using Android.Webkit;
 using AndroidX.Activity;
+using Bumptech.Glide.Load.Engine;
 using chdTour.App.Platforms.Android;
 #endif
 using Microsoft.AspNetCore.Components.WebView;
 using Microsoft.Maui.Platform;
+using System.Text.RegularExpressions;
 
 namespace chdTour.App
 {
@@ -40,7 +43,6 @@ private partial void BlazorWebViewInitializing(object? sender, BlazorWebViewInit
 
         private partial void BlazorWebViewInitialized(object? sender, BlazorWebViewInitializedEventArgs e)
         {
-
         }
 #endif
 
@@ -56,20 +58,18 @@ private partial void BlazorWebViewInitialized(object? sender, BlazorWebViewIniti
         private partial void BlazorWebViewInitializing(object? sender, BlazorWebViewInitializingEventArgs e)
         {
         }
-
         private async Task CheckPermissions()
         {
-
-#if ANDROID
             PermissionStatus statusNotification = await Permissions.RequestAsync<PermissionValidator>();
-#endif
         }
 
 
         private partial void BlazorWebViewInitialized(object? sender, BlazorWebViewInitializedEventArgs e)
         {
             try
             {
+                e.WebView.Download += this.WebView_DownloadAsync;
+
                 if (e.WebView.Context?.GetActivity() is not ComponentActivity activity)
                 {
                     throw new InvalidOperationException($"The permission-managing WebChromeClient requires that the current activity be a '{nameof(ComponentActivity)}'.");
@@ -87,6 +87,49 @@ private partial void BlazorWebViewInitialized(object? sender, BlazorWebViewIniti
             }
 
         }
+
+        private async void WebView_DownloadAsync(object sender, DownloadEventArgs e)
+        {
+            Uri uri = new Uri(e.Url);
+            await DownloadAsync(uri, e.Mimetype);
+        }
+
+
+        public static string DataUrl2Filename(string base64encodedstring)
+        {
+            var filename = Regex.Match(base64encodedstring, @"data:text/(?<filename>.+?);(?<type2>.+?),(?<data>.+)").Groups["filename"].Value;
+            return filename;
+        }
+        public static byte[] DataUrl2Bytes(string base64encodedstring)
+        {
+            var base64Data = Regex.Match(base64encodedstring, @"data:text/(?<type>.+?),(?<data>.+)").Groups["data"].Value;
+            var bytes = Convert.FromBase64String(base64Data);
+            return bytes;
+        }
+
 #endif
+
+        private async Task DownloadAsync(Uri uri, string? mimeType = null)
+        {
+            var UploadPath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), "uploads");
+
+            string fileName = Path.GetFileName(uri.LocalPath);
+            var httpClient = new HttpClient();
+            var filePath = Path.Combine(UploadPath, fileName);
+#if ANDROID
+            if (uri.Scheme == "data")
+            {
+                fileName = DataUrl2Filename(uri.OriginalString);
+                filePath = Path.Combine(UploadPath, $"{DateTime.Now.ToString("yyyy-MM-dd-hhmmss")}-{fileName}");
+                var bytes = DataUrl2Bytes(uri.OriginalString);
+                File.WriteAllBytes(filePath, bytes);
+                await DisplayAlert("Download", $"Fertig {fileName}", "OK");
+                return;
+            }
+#endif
+            byte[] fileBytes = await httpClient.GetByteArrayAsync(uri);
+            File.WriteAllBytes(filePath, fileBytes);
+            await DisplayAlert("Download", $"Fertig {fileName}", "OK");
+        }
     }
 }

src/chdTour.App/wwwroot/index.html

@@ -29,6 +29,7 @@
     <script src="_content/chd.UI.Base.Components/js/qrcode.js"></script>
 
     <script src="_framework/blazor.webview.js" autostart="false"></script>
+    <script src="js/app.js" autostart="false"></script>
 
 </body>
 

src/chdTour.App/wwwroot/js/app.js

@@ -0,0 +1,11 @@
+ window.downloadFileFromStream = async (fileName, contentStreamReference) => {
+    const arrayBuffer = await contentStreamReference.arrayBuffer();
+    const blob = new Blob([arrayBuffer]);
+    const url = URL.createObjectURL(blob);
+    const anchorElement = document.createElement('a');
+    anchorElement.href = url;
+    anchorElement.download = fileName ?? '';
+    anchorElement.click();
+    anchorElement.remove();
+    URL.revokeObjectURL(url);
+  }