Xamarin Android 将图像保存到图库

Question

I can't seem to get my App to save an image, outside of my App folder. I can save internally (image will save to app folder) but not externally. I want to see photos taken with my App in the default device gallery. I believe i have all the required App permissions. Here is my code:

\\MainActivity
    using System;
    using TCmCRS_20;
    using Android.App;
    using Android.Content.PM;
    using Android.Runtime;
    using Android.Views;
    using Android.Widget;
    using Android.OS;
    using SQLite;
    using System.IO;
    using Xamarin.Essentials;
    using Acr.UserDialogs;
    using Plugin.Media;
    
    
    namespace TCmCRS_20.Droid
    {
        [Activity(Label = "TCmCRS_20", Icon = "@mipmap/icon", Theme = "@style/MainTheme", MainLauncher = true, ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation)]
        public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity
        {
    
            protected override async void OnCreate(Bundle savedInstanceState)
            {
    
                TabLayoutResource = Resource.Layout.Tabbar;
                ToolbarResource = Resource.Layout.Toolbar;
    
                base.OnCreate(savedInstanceState);
    
                Xamarin.Essentials.Platform.Init(this, savedInstanceState);
                await CrossMedia.Current.Initialize();
    
                global::Xamarin.Forms.Forms.Init(this, savedInstanceState);
                Xamarin.FormsMaps.Init(this, savedInstanceState);
                UserDialogs.Init(this);
    
    
                string fileName = "TCmCRS_20_db.db3";
                string folderPath = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal);
                string completePath = System.IO.Path.Combine(folderPath,fileName);
    
                LoadApplication(new App(completePath));
    
            }
            public override void OnRequestPermissionsResult(int requestCode, string[] permissions, Android.Content.PM.Permission[] grantResults)
            {
                Xamarin.Essentials.Platform.OnRequestPermissionsResult(requestCode, permissions, grantResults);
                base.OnRequestPermissionsResult(requestCode, permissions, grantResults);
            }
        }
    }

//Android Manifest

    <?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="1" android:versionName="1.0" package="com.companyname.TCmCRS_20" android:installLocation="preferExternal">
    <uses-sdk android:minSdkVersion="25" android:targetSdkVersion="29" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-feature android:name="android.hardware.location" android:required="false" />
    <uses-feature android:name="android.hardware.location.gps" android:required="false" />
    <uses-feature android:name="android.hardware.location.network" android:required="false" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
    <uses-permission android:name="android.permission.CAMERA" />
    <uses-permission android:name="android.permission.ACCESS_LOCATION_EXTRA_COMMANDS" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <application android:label="TCmCRS_20.Android">
        <provider android:name="android.support.v4.content.FileProvider" android:authorities="${applicationId}.fileprovider" android:exported="false" android:grantUriPermissions="true">
            <meta-data android:name="android.support.FILE_PROVIDER_PATHS" android:resource="@xml/file_paths"></meta-data>
        </provider>
        <meta-data android:name="com.google.android.maps.v2.API_KEY" android:value="AIzaSyADDISS9WBQw8XYyWGkIF0Q5TtiAW9b_ao" />
        <meta-data android:name="com.google.android.gms.version" android:value="@integer/google_play_services_version" />
        <uses-library android:name="org.apache.http.legacy" android:required="false" />
    </application>
</manifest>



        

private async void TakePhotoButton_OnClicked(object sender, EventArgs e)

        {
            var location = await Geolocation.GetLocationAsync();

            if (location != null)
            {
                PhotoLatCoord.Text = location.Latitude.ToString();
                PhotoLonCoord.Text = location.Longitude.ToString();
            }
            else
            {
                ;
            }

            string gID = Guid.NewGuid().ToString();
            string fN = "RI-" + Asset_ID.Text + " " + gID + ".jpg";

            if (!CrossMedia.Current.IsCameraAvailable || !CrossMedia.Current.IsTakePhotoSupported)
            {
                await DisplayAlert("No Camera", "No camera available", "OK");
                return;
            }

            await CrossMedia.Current.Initialize();
            var current = Connectivity.NetworkAccess;


            if (current != NetworkAccess.Internet)
            {
                var file = await CrossMedia.Current.TakePhotoAsync(new 
                   Plugin.Media.Abstractions.StoreCameraMediaOptions
                {
                    Name = fN,
                    Directory = "All_Photos",
                    SaveToAlbum = true,
                });
            }
            else
            {
                var file = await CrossMedia.Current.TakePhotoAsync(new 
                Plugin.Media.Abstractions.StoreCameraMediaOptions
                {
                    Name = fN,
                    Directory = "Photos_for_Upload",
                    SaveToAlbum = true,
                });



                //Get the public album path
                var aPpath = file.AlbumPath;

                //Get private path
                var path = file.Path;

                //! added using Microsoft.WindowsAzure.Storage;
                var account = CloudStorageAccount.Parse("xxxhiddenxxx");
                var blobClient = account.CreateCloudBlobClient();

                var container = blobClient.GetContainerReference("xxx");

                var blockBlob = container.GetBlockBlobReference(fN);

                if (file == null)
                    return;
                {
                    MainImage.Source = ImageSource.FromStream(() => file.GetStream());
                    await blockBlob.UploadFromStreamAsync(file.GetStream());
                }
            }
        }

Any help would be greatly appreciated

Answer 1

I think adding android:requestLegacyExternalStorage="true" to your manifest <application> tag as mentioned here: Xamarin-System.UnauthorizedAccessException: Access to the path is denied in combination with the native android path for pictures Android.OS.Environment.GetExternalStoragePublicDirectory(Android.OS.Environment.DirectoryPictures).AbsolutePath; will help you.