I'm new in Xamarin development.
I build my app, where user can clicks on DOWNLOAD button. This button download video from the server and save to Photo library.
Here is how I implement this (maybe its incorrect way??)
public bool SaveVideo(byte[] videoData, int id)
{
try
{
CreateCustomAlbum();
// Save file to applicaiton folder
string local_path = SaveFileToApplicationFolder(videoData);
_lib.WriteVideoToSavedPhotosAlbum(new Foundation.NSUrl(local_path), (t, u) =>
{
DeleteLocalFile(local_path); // HERE I DELETE FILE FOR NOT INCREASE SIZE OF APPLICATION
_local_file_path = t.AbsoluteUrl.ToString(); // global variable
_lib.Enumerate(ALAssetsGroupType.Album, HandleALAssetsLibraryGroupsEnumerationResultsDelegate, (obj) => { });
});
return true;
}
catch (Exception ex)
{
return false;
}
}
void DeleteLocalFile(string local_path)
{
try
{
if (File.Exists(local_path))
{
File.Delete(local_path);
if (!File.Exists(local_path))
{
Console.WriteLine("Deleted");
}
}
}
catch (Exception ex)
{
}
}
string SaveFileToApplicationFolder(byte[] videoData)
{
try
{
string file_path = String.Empty;
var doc = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
string filename = "MY-APP-" + id + ".mp4"; // id global variable
file_path = Path.Combine(doc, filename); // global variable
File.WriteAllBytes(file_path, videoData);
return file_path;
}
catch (Exception ex)
{
return String.Empty;
}
}
void HandleALAssetsLibraryGroupsEnumerationResultsDelegate(ALAssetsGroup group, ref bool stop)
{
try
{
if (group == null)
{
stop = true;
return;
}
if (group.Name == "MY-APP-ALBUM-NAME")
{
stop = true;
_current_album = group;
SaveFileToCustomAlbum();
}
}
catch (Exception ex)
{
}
}
void SaveFileToCustomAlbum()
{
try
{
if (_current_album != null && !String.IsNullOrEmpty(_local_file_path))
{
_lib.AssetForUrl(new Foundation.NSUrl(_local_file_path), delegate (ALAsset asset)
{
if (asset != null)
{
_current_album.AddAsset(asset);
}
else
{
Console.WriteLine("ASSET == NULL.");
}
}, delegate (NSError assetError)
{
Console.WriteLine(assetError.ToString());
});
}
}
catch (Exception ex)
{
}
}
So this code do: 1) Save video to local folder my video - Method SaveFileToApplicationFolder 2) Then Save video file to Photo library - Method SaveVideo 3) Then Delete file from app folder (in purpose not increase application folder size (app size) --- IF ITS CORRECT logic?? 4) Then put assets to Custom Album for my App
SO everything here works well for me......BUT! I need overtime when user open item - check if he already has video for this item in photos library or not?
And here I'm stack....i just don't understand how i can to check if user has specific video?? I don't find hot to set NAME for ASSETS and hot looking for assets by name...so don't know hot to find this assets....METADATA?? Key_VALUE of object??
