I have worked with pdfjs and its working fine with local storage pdf, but I have another issue: I need to display pdf from WEB API, as I have stored binary data of pdf which I need to display?? this is my code
public pdfjsPage(string url)
{
InitializeComponent();
var localPath = string.Empty;
if (Device.RuntimePlatform == Device.Android)
{
var dependency = DependencyService.Get<ILocalFileProvider>();
if (dependency == null)
{
DisplayAlert("Error loading PDF", "Computer says no", "OK");
return;
}
var fileName = Guid.NewGuid().ToString();
// Download PDF locally for viewing
using (var httpClient = new HttpClient())
{
var pdfStream = Task.Run(() => httpClient.GetStreamAsync(url)).Result;
localPath =
Task.Run(() => dependency.SaveFileToDisk(pdfStream, $"{fileName}.pdf")).Result;
}
if (string.IsNullOrWhiteSpace(localPath))
{
DisplayAlert("Error loading PDF", "Computer says no", "OK");
return;
}
}
if (Device.RuntimePlatform == Device.Android)
PdfView.Source = $"file:///android_asset/pdfjs/web/viewer.html?file={WebUtility.UrlEncode(localPath)}";
else
PdfView.Source = url;
}
This is working with local pdf, but I have WEB API URL and I need to get pdf from there online.
This is the link from where I retrieve it: http://veezo2007pkk.somee.com/api/DiagnosticDetail/RetrieveFile/1
After saving your PDF to your device, pass the path to an Intent.
//Example
var fileName = "/storage/emulated/0/yourPDF.pdf"
Uri pdfPath = Uri.FromFile(new File(fileName));
Intent intent = new Intent(Intent.ActionView);
intent.SetDataAndType(pdfPath, "application/pdf");
intent.SetFlags(ActivityFlags.NewTask);
Android.App.Application.Context.StartActivity(intent);
Related
I need to check current version of Installed Application and Playstore application version. If it is not same app should navigate to Playstore .
im using xam.Plugin.LatestVersion(2.1.0) To get the latestversion number of application from play console. unfortunately not getting latest version number of application from play store. The below code im using.
private async void ChekAppVersion()
{
try
{
latestVersionNumber = await CrossLatestVersion.Current.GetLatestVersionNumber();
installedVersionNumber = CrossLatestVersion.Current.InstalledVersionNumber;
if (installedVersionNumber != latestVersionNumber)
{
await DisplayAlert("New Version", "There is a new version of this app available. Please update now?", "Ok");
await CrossLatestVersion.Current.OpenAppInStore();
ChekAppVersion();
}
else
{
}
}
catch (Exception ex)
{
}
}
Im getting the installedVersionNumber, but im unable to get the latestVersionNumber(Playstore).
Please help on this.
They have removed the version from div, now it's displayed with js, but data is still there inside a <script> tag. My current fixed code is:
private bool _lockCheckUpdates;
public async Task<bool> CheckNeedUpdate()
{
if (Connectivity.NetworkAccess != NetworkAccess.Internet || _lockCheckUpdates)
return false;
_lockCheckUpdates = true;
try
{
HttpClient myClient = CreateClient();
if (Device.RuntimePlatform == Device.Android)
{
var bundle = "com.todo.app"; //ANDROID BUNDLE NAME HERE
string url = $"https://play.google.com/store/apps/details?id={bundle}&hl=en";
string raw = await myClient.GetStringAsync(new Uri(url));
var doc = new HtmlDocument();
doc.LoadHtml(raw);
var scripts = doc.DocumentNode.Descendants()
.Where(n => n.Name == "script" && n.InnerText.Contains("AF_initDataCallback({key: 'ds:4'"))
.ToArray();
var script = scripts.First().InnerText;
var engine = new Jurassic.ScriptEngine();
var eval = "(function() { var AF_initDataCallback = function(p) { return p.data[1][2][140][0][0][0]; }; return " + script + " })()";
var result = engine.Evaluate(eval);
//var json = JSONObject.Stringify(engine, result); //for debug, check in browser console with JSON.parse(json)
var remote = $"{result}".ToDouble();
var local = App.Version.ToDouble();
return local < remote;
}
else if (Device.RuntimePlatform == Device.iOS)
{
var bundle = "com.todo.app";//iOS BUNDLE NAME HERE
string url = $"http://itunes.apple.com/lookup?bundleId={bundle}";
string raw = await myClient.GetStringAsync(new Uri(url));
var dto = JsonConvert.DeserializeObject<AppStoreRecord>(raw);
double local = App.Version.ToDouble();
if (dto.ResultCount > 0)
{
double remote = dto.Results[0].Version.ToDouble();
return remote > local;
}
}
}
catch (Exception e)
{
Logger.Error("CheckNeedUpdate", e);
}
finally
{
_lockCheckUpdates = false;
}
return false;
}
Using nugets
Jurassic to evaluate the script on page,
HtmlAgilityPack to parse html,
Xamarin.Essentials to check if we are online,
and AppoMobi.Specials for .ToDouble() etc
I hope this could also be useful to fix https://github.com/edsnider/latestversionplugin/issues/43 :)
The plugin you are using no longer works for Android https://github.com/edsnider/latestversionplugin/issues/43
You will need to find a new way to get the desired information.
PR has been made on this plugin... it works again ;-)
Hello, would any of you send a working code to download a photo from a given http address on android Xamarin c #?
First, I need to create a new folder for my application files.
My goal is to download the file from the internet to my Android folder (saving this file with its original name is best).
The next step is to display the image from that folder in "ImageView". It is also important that there are permissions in android and I do not fully understand it.
Could any of you send it to me or help me understand it and explain the topic?
*Actually i have this code:
string address = "https://i.stack.imgur.com/X3V3w.png";
using (WebClient webClient = new WebClient())
{
webClient.DownloadFileCompleted += WebClient_DownloadFileCompleted;
webClient.DownloadFile(address, Path.Combine(pathDire, "MyNewImage1.png"));
//System.Net.WebException: 'An exception occurred during a WebClient request.'
}
Loading image from url and display in imageview.
private void Btn1_Click(object sender, System.EventArgs e)
{
var imageBitmap = GetImageBitmapFromUrl("http://xamarin.com/resources/design/home/devices.png");
imagen.SetImageBitmap(imageBitmap);
}
private Bitmap GetImageBitmapFromUrl(string url)
{
Bitmap imageBitmap = null;
using (var webClient = new WebClient())
{
var imageBytes = webClient.DownloadData(url);
if (imageBytes != null && imageBytes.Length > 0)
{
SavePicture("ImageName.jpg", imageBytes, "imagesFolder");
imageBitmap = BitmapFactory.DecodeByteArray(imageBytes, 0, imageBytes.Length);
}
}
return imageBitmap;
}
download image and save it in local storage.
private void SavePicture(string name, byte[] data, string location = "temp")
{
var documentsPath = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal);
documentsPath = System.IO.Path.Combine(documentsPath, "Orders", location);
Directory.CreateDirectory(documentsPath);
string filePath = System.IO.Path.Combine(documentsPath, name);
using (FileStream fs = new FileStream(filePath, FileMode.OpenOrCreate))
{
int length = data.Length;
fs.Write(data, 0, length);
}
}
you need to add permission WRITE_EXTERNAL_STORAGE and READ_EXTERNAL_STORAGE in AndroidMainfeast.xml, then you also need to Runtime Permission Checks in Android 6.0.
private void checkpermission()
{
if (ContextCompat.CheckSelfPermission(this, Manifest.Permission.WriteExternalStorage) == (int)Permission.Granted)
{
// We have permission, go ahead and use the writeexternalstorage.
}
else
{
// writeexternalstorage permission is not granted. If necessary display rationale & request.
}
if (ContextCompat.CheckSelfPermission(this, Manifest.Permission.ReadExternalStorage) == (int)Permission.Granted)
{
// We have permission, go ahead and use the ReadExternalStorage.
}
else
{
// ReadExternalStorage permission is not granted. If necessary display rationale & request.
}
}
Call Rest service
Rest service returns byte[] representation of image/audio/video
convert into byte[] to image and show in content page in xamarin
First of all, you can create a function that simply makes an API request and obtains the content in the form of byte array. A simple example of HTTP request:
public static byte[] GetImageByteArray(string url)
{
try
{
using (var client = new HttpClient())
{
var uri = new Uri(url);
var response = client.GetAsync(uri).Result;
if (response.IsSuccessStatusCode)
{
var content = response.Content.ReadAsByteArrayAsync();
return content.Result;
}
}
return null;
}
catch
{
return null;
}
}
Next, you can simply bind the output from your result into your image source and the image to your content:
var mainStack = new StackLayout();
var imageByteArray = GetImageByteArray("https://static.pexels.com/photos/34950/pexels-photo.jpg");
Image image;
if (imageByteArray != null)
{
image = new Image()
{
Source = ImageSource.FromStream(() => new MemoryStream(imageByteArray))
};
mainStack.Children.Add(image);
}
Content = mainStack;
How to get file image source from file path in Xamarin Forms here i have stored a folder locally by using dependency services.
_fileHelper = _fileHelper ?? DependencyService.Get<IFileHelper>();
profiletap.Tapped += async (s, e) =>
{
var file = await CrossMedia.Current.PickPhotoAsync();
if (file == null)
return;
await DisplayAlert("File Location", file.Path, "OK");
profile.Source = im;
imageName = "SomeUniqueFileName" + DateTime.Now.ToString("yyyy-MM-dd_hh-mm-ss-tt");
filePath = _fileHelper.CopyFile(file.Path, imageName);
im = ImageSource.FromFile(filePath)
}
i want to upload image from media picker permanently so that i can not loose image once uploaded public string CopyFile(string sourceFile, string destinationFilename, bool overwrite = true)
{
if (!File.Exists(sourceFile)) { return string.Empty; }
string fullFileLocation = Path.Combine(System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal) );
File.Copy(sourceFile, fullFileLocation, overwrite);
return fullFileLocation;
}
im = ImageSource.FromStream(()=> file.GetStream());
I need to load a picture from a web api backend into my Xamarin.Forms app.
The picture is stored in an Azure Blob Storage.
This is my Web Api method:
[HttpGet("{id}")]
public HttpResponseMessage Get(int id)
{
// Retrieve storage account from connection string.
CloudStorageAccount storageAccount = CloudStorageAccount.Parse("ConnectionString");
// Create the blob client.
CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();
// Retrieve reference to a previously created container.
CloudBlobContainer container = blobClient.GetContainerReference("picturecontainer");
// Retrieve reference to a blob named "photo.jpg".
CloudBlockBlob blockBlob = container.GetBlockBlobReference("picture");
var stream = new MemoryStream();
blockBlob.DownloadToStream(stream);
Image image = Image.FromStream(stream);
MemoryStream memoryStream = new MemoryStream();
image.Save(memoryStream, ImageFormat.Jpeg);
HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);
result.Content = new ByteArrayContent(memoryStream.ToArray());
result.Content.Headers.ContentType = new MediaTypeHeaderValue("image/jpeg");
return result;
}
In my app I try to download the image bytes with the following code:
public App ()
{
_client = new HttpClient();
_client.MaxResponseContentBufferSize = 256000;
Button downloadImageBtn = new Button () {
Text = "Download Image",
};
var image = new Image() {
Source = ImageSource.FromUri (new Uri ("http://www.engraversnetwork.com/files/placeholder.jpg")),
Aspect = Aspect.AspectFit
};
downloadImageBtn.Clicked += async (object sender, EventArgs e) => {
var values = await handleClick (sender, e);
uploadPicButton.Text = values;
var imageBytes = await downloadPicture();
image.Source = ImageSource.FromStream(() => new MemoryStream(imageBytes));
};
MainPage = new ContentPage {
Content = new StackLayout {
VerticalOptions = LayoutOptions.Center,
Children = {
image,
downloadImageBtn
}
}
};
}
private async Task<byte[]> downloadPicture()
{
var uri = new Uri (string.Format (RestUrl, "5"));
//return await _client.GetByteArrayAsync (uri);
var response = await _client.GetAsync (uri);
if (response.IsSuccessStatusCode) {
var content = await response.Content.ReadAsByteArrayAsync ();
return content;
}
throw new HttpRequestException ();
}
However when I click on the button, the placeholder image disappears.
Is there a problem when sending the image from the server or when receiving it in the app?
I'd not implement downloading Images manually.
If you want to load more images and/or allow to display a placeholder while loading, I recommend the FFImageLoading library. It offers nice functionality like downloading, caching, showing placeholder and error images and most important: down sampling the image to the target size. This is always a pain on android. Its available for native UI xamarin projects and for Xamarin.Froms.
You can bind strings that contain urls directly to the Source. The code would like like:
<ffimageloading:CachedImage
Source="http://thecatapi.com/?id=MTQ5MzcyNA">
</ffimageloading:CachedImage>
After blockblob.DownloadToStream line, try to set Position of the stream to 0. I'm not familiar with Azure API, but I think it may help.
Also ,try to use ReadAsStreamAsync instead of ReadAsByteArrayAsync in your downloadPicture function. Something like this:
var responseStream = await response.Content.ReadAsStreamAsync();
byte[] buf = new byte[512];
int bufSize;
while((bufSize = (await responseStream.ReadAsync(buf, 0, buf.Length))) > 0)
{
// store the received bytes to some buffer until the file is fully downloaded
}
Do you get all your content this way?