attachments on view page abd device actions

src/Android/MainApplication.cs

@@ -46,7 +46,6 @@ namespace Bit.Droid
             var documentsPath = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
             var liteDbStorage = new LiteDbStorageService(Path.Combine(documentsPath, "bitwarden.db"));
             liteDbStorage.InitAsync();
-            var deviceActionService = new DeviceActionService();
             var localizeService = new LocalizeService();
             var broadcasterService = new BroadcasterService();
             var messagingService = new MobileBroadcasterMessagingService(broadcasterService);
@@ -54,6 +53,7 @@ namespace Bit.Droid
             var secureStorageService = new SecureStorageService();
             var cryptoPrimitiveService = new CryptoPrimitiveService();
             var mobileStorageService = new MobileStorageService(preferencesStorage, liteDbStorage);
+            var deviceActionService = new DeviceActionService(mobileStorageService);
             var platformUtilsService = new MobilePlatformUtilsService(deviceActionService, messagingService,
                 broadcasterService);
 

src/Android/Properties/AndroidManifest.xml

@@ -26,5 +26,14 @@
     android:icon="@mipmap/ic_launcher"
     android:roundIcon="@mipmap/ic_launcher_round"
     android:networkSecurityConfig="@xml/network_security_config">
+    <provider
+      android:name="android.support.v4.content.FileProvider"
+      android:authorities="com.x8bit.bitwarden.fileprovider"
+      android:exported="false"
+      android:grantUriPermissions="true">
+      <meta-data
+        android:name="android.support.FILE_PROVIDER_PATHS"
+        android:resource="@xml/filepaths" />
+    </provider>
   </application>
 </manifest>

src/Android/Services/DeviceActionService.cs

@@ -1,6 +1,14 @@
-using System.Threading.Tasks;
+using System;
+using System.IO;
+using System.Threading.Tasks;
 using Android.App;
+using Android.Content;
+using Android.Content.PM;
+using Android.Support.V4.Content;
+using Android.Webkit;
 using Bit.App.Abstractions;
+using Bit.Core;
+using Bit.Core.Abstractions;
 using Bit.Core.Enums;
 using Plugin.CurrentActivity;
 
@@ -8,9 +16,16 @@ namespace Bit.Droid.Services
 {
     public class DeviceActionService : IDeviceActionService
     {
+        private readonly IStorageService _storageService;
+
         private ProgressDialog _progressDialog;
         private Android.Widget.Toast _toast;
 
+        public DeviceActionService(IStorageService storageService)
+        {
+            _storageService = storageService;
+        }
+
         public DeviceType DeviceType => DeviceType.Android;
 
         public void Toast(string text, bool longDuration = false)
@@ -61,5 +76,100 @@ namespace Bit.Droid.Services
             }
             return Task.FromResult(0);
         }
+
+        public bool OpenFile(byte[] fileData, string id, string fileName)
+        {
+            if(!CanOpenFile(fileName))
+            {
+                return false;
+            }
+            var extension = MimeTypeMap.GetFileExtensionFromUrl(fileName.Replace(' ', '_').ToLower());
+            if(extension == null)
+            {
+                return false;
+            }
+            var mimeType = MimeTypeMap.Singleton.GetMimeTypeFromExtension(extension);
+            if(mimeType == null)
+            {
+                return false;
+            }
+
+            var activity = (MainActivity)CrossCurrentActivity.Current.Activity;
+            var cachePath = activity.CacheDir;
+            var filePath = Path.Combine(cachePath.Path, fileName);
+            File.WriteAllBytes(filePath, fileData);
+            var file = new Java.IO.File(cachePath, fileName);
+            if(!file.IsFile)
+            {
+                return false;
+            }
+
+            try
+            {
+                var intent = new Intent(Intent.ActionView);
+                var uri = FileProvider.GetUriForFile(activity.ApplicationContext,
+                    "com.x8bit.bitwarden.fileprovider", file);
+                intent.SetDataAndType(uri, mimeType);
+                intent.SetFlags(ActivityFlags.GrantReadUriPermission);
+                activity.StartActivity(intent);
+                return true;
+            }
+            catch { }
+            return false;
+        }
+
+        public bool CanOpenFile(string fileName)
+        {
+            var extension = MimeTypeMap.GetFileExtensionFromUrl(fileName.Replace(' ', '_').ToLower());
+            if(extension == null)
+            {
+                return false;
+            }
+            var mimeType = MimeTypeMap.Singleton.GetMimeTypeFromExtension(extension);
+            if(mimeType == null)
+            {
+                return false;
+            }
+            var activity = (MainActivity)CrossCurrentActivity.Current.Activity;
+            var intent = new Intent(Intent.ActionView);
+            intent.SetType(mimeType);
+            var activities = activity.PackageManager.QueryIntentActivities(intent, PackageInfoFlags.MatchDefaultOnly);
+            return (activities?.Count ?? 0) > 0;
+        }
+
+        public async Task ClearCacheAsync()
+        {
+            try
+            {
+                DeleteDir(CrossCurrentActivity.Current.Activity.CacheDir);
+                await _storageService.SaveAsync(Constants.LastFileCacheClearKey, DateTime.UtcNow);
+            }
+            catch(Exception) { }
+        }
+
+        private bool DeleteDir(Java.IO.File dir)
+        {
+            if(dir != null && dir.IsDirectory)
+            {
+                var children = dir.List();
+                for(int i = 0; i < children.Length; i++)
+                {
+                    var success = DeleteDir(new Java.IO.File(dir, children[i]));
+                    if(!success)
+                    {
+                        return false;
+                    }
+                }
+                return dir.Delete();
+            }
+            else if(dir != null && dir.IsFile)
+            {
+                return dir.Delete();
+            }
+            else
+            {
+                return false;
+            }
+        }
     }
 }