On a WPF project, I need to set a ImageSource property from a local Resource.
I am trying to use the following code:
var bmp = new BitmapImage();
bmp.BeginInit();
bmp.UriSource = new Uri("pack://application:,,,/Resources/Identicons/no_user.jpg", UriKind.Absolute);
bmp.EndInit();
Avatar = bmp;
Where Avatar is defined before as:
private ImageSource myAvatar;
The problem is that BitmapImage does not support MetaData information, that the source image have (it was created with Paint.net) so it throws a error. The error is the following:
Metadata = 'bmp.Metadata' threw an exception of type
'System.NotSupportedException'
So I believe that I need alternatives to BitmapImage to properly load the desired image.
As a end note, using the same image inside xaml, directly in a "source" property it works fine.
Thank you
Unlike BitmapImage, BitmapFrame supports the Metadata property:
So you may replace
Avatar = new BitmapImage(new Uri(...));
by
Avatar = BitmapFrame.Create(new Uri(...));
From MSDN:
BitmapFrame provides additional functionality not defined by
BitmapSource ... BitmapFrame also supports the writing of metadata
information by using the Metadata property or the
CreateInPlaceBitmapMetadataWriter method.
As you have the path to the image it can be done by below using Image Control,
XAML
<Image>
<Image.Source>
<BitmapImage UriSource="{Binding ImagePath}"></BitmapImage>
</Image.Source>
</Image>
VM
public ViewerViewModel()// Constructor
{
ImagePath = #"..\Images\Untitled.jpg";// Change the image path based on your input.
}
private string _ImagePath = string.Empty;
public string ImagePath {
get { return _ImagePath; }
set { _ImagePath = value; NotifyPropertyChanged(); }
}
Problem solved.
This was inside a Class with the property:
private ImageSource myAvatar;
....
public ImageSource Avatar
{
set { myAvatar = Avatar; }
get { return myAvatar; }
}
And I was trying to change the Avatar (that sets the myAvatar through the set).
I do not understand why, but changing directly the myAvatar works. For example doing:
BitmapSource image = BitmapFrame.Create(new Uri("pack://application:,,,/Resources/Identicons/no_user.jpg", UriKind.Absolute));
myAvatar = image;
Is ok, but:
BitmapSource image = BitmapFrame.Create(new Uri("pack://application:,,,/Resources/Identicons/no_user.jpg", UriKind.Absolute));
Avatar = image;
Always sets Avatar as null.
This is a method inside a class. I would appreciate to understand why as it is not clear to me. Thank you.
Related
I have a view that contains an image control that is binded to this property:
private System.Drawing.Image _sigImage;
public System.Drawing.Image sigImage
{
get { return _sigImage; }
set { _sigImage = value; RaisePropertyChanged(); }
}
I am busy implementing a a signature pad using mvvm, and want the signature to display in the image control. However i cant get it to display.
The code for die signature pad is:
DynamicCapture dc = new DynamicCaptureClass();
DynamicCaptureResult res = dc.Capture(sigCtl, "Who", "Why", null, null);
if (res == DynamicCaptureResult.DynCaptOK)
{
sigObj = (SigObj)sigCtl.Signature;
sigObj.set_ExtraData("AdditionalData", "C# test: Additional data");
try
{
byte[] binaryData = sigObj.RenderBitmap("sign", 200, 150, "image/png", 0.5f, 0xff0000, 0xffffff, 10.0f, 10.0f, RBFlags.RenderOutputBinary | RBFlags.RenderColor32BPP) as byte[];
using (MemoryStream memStream = new MemoryStream(binaryData))
{
System.Drawing.Image newImage = System.Drawing.Image.FromStream(memStream);
sigImage = newImage;
// work with image here.
// You'll need to keep the MemoryStream open for
// as long as you want to work with your new image.
memStream.Dispose();
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
The image is stored as a bitmap in the variable newImage.
How can i bind that image to the image control of sigImage?
System.Drawing.Image is not an appropriate type for the Source property of an Image element. It is WinForms, not WPF.
Use System.Windows.Media.ImageSource instead
private ImageSource sigImage;
public ImageSource SigImage
{
get { return sigImage; }
set { sigImage = value; RaisePropertyChanged(); }
}
and assign a BitmapImage or BitmapFrame to the property, which is directly created from the MemoryStream. BitmapCacheOption.OnLoad has to be set in order to enable closing the stream immediately after decoding the bitmap.
var bitmapImage = new BitmapImage();
using (var memStream = new MemoryStream(binaryData))
{
bitmapImage.BeginInit();
bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
bitmapImage.StreamSource = memStream;
bitmapImage.EndInit();
}
bitmapImage.Freeze();
SigImage = bitmapImage;
The Binding would look like shown below, provided an instance of the class with the SigImage property is assigned to the DataContext of the view.
<Image Source="{Binding SigImage}"/>
Since WPF has built-in type conversion from string, Uri and byte[] to ImageSource, you may as well declare the source property as byte[]
private byte[] sigImage;
public byte[] SigImage
{
get { return sigImage; }
set { sigImage = value; RaisePropertyChanged(); }
}
and assign a value like
SigImage = binaryData;
without manually creating a BitmapImage or BitmapFrame, or changing the Binding.
I am just beginning to experiment with Ghostscript.Net. My goal is to adapt the GhostscriptViewer to my WPF MVVM Modular environment, but I am not able to display a page in a XAML Image control. I suspect that my problem lies either in my inadequate knowledge of Ghostscript.Net or in not understanding how to bind the image parameter to the image control.
In this app, I am using Prism with the UnityContainer. The PdfPageImage property in PdfViewModel is bound to the image control in the view XAML. The conversion, which takes place in the _viewer_displaypage method gives PdfPageImage an object of type System.Windows.Interop.InteropBitmap. I was thinking that the RaisePropertyChangedEvent method would cause the control to be updated with the ImageSource object.
<Image x:Name="PdfDocumentImage" Grid.Column="1" Grid.Row="0"
Source="{Binding PdfPageImage}"
Height="100"
Width="100">
</Image>
public class PdfViewModel : ViewModelBase, IPdfViewModel
{
private readonly IBitmapToImageSourceConverter _imageSourceConverter;
private readonly GhostscriptViewer _ghostscriptViewer;
private readonly GhostscriptVersionInfo _gsVersion =
GhostscriptVersionInfo.GetLastInstalledVersion(GhostscriptLicense.GPL |
GhostscriptLicense.AFPL, GhostscriptLicense.GPL);
private ImageSource _pdfPageImage;
public ImageSource PdfPageImage
{
get => _pdfPageImage;
set
{
if (value == _pdfPageImage) return;
_pdfPageImage = value;
RaisePropertyChangedEvent(nameof(PdfPageImage));
}
}
public PdfViewModel(IPdfView view,
IEventAggregator eventAggregator,
IBitmapToImageSourceConverter imageSourceConverter,
GhostscriptViewer ghostscriptViewer)
: base(view)
{
_ghostscriptViewer = ghostscriptViewer;
_imageSourceConverter = imageSourceConverter;
_ghostscriptViewer.DisplayPage += _viewer_DisplayPage;
eventAggregator.GetEvent<PdfDocumentOpenedEvent>().Subscribe(OpenPdfDocument, ThreadOption.UIThread);
}
private void _viewer_DisplayPage(object sender, GhostscriptViewerViewEventArgs e)
{
PdfPageImage = _imageSourceConverter.ImageSourceForBitmap(e.Image);
}
private void OpenPdfDocument(string path)
{
_ghostscriptViewer.Open(path, _gsVersion, false);
}
}
public class BitmapToImageSourceConverter : IBitmapToImageSourceConverter
{
[DllImport("gdi32.dll", EntryPoint = "DeleteObject")]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool DeleteObject(IntPtr hObject);
public ImageSource ImageSourceForBitmap(Bitmap bmp)
{
var handle = bmp.GetHbitmap();
try
{
return Imaging.CreateBitmapSourceFromHBitmap(handle, IntPtr.Zero, Int32Rect.Empty, BitmapSizeOptions.FromEmptyOptions());
}
finally { DeleteObject(handle); }
}
}
Okay. So I figured it out. My solution isn't perfect; while paging through a pdf document, the page orientation isn't correct, but other than that, it works.
The key was to use a memorystream in creating a BitmapImage:
public static BitmapImage ConvertBitmapToImage(System.Drawing.Image image)
{
using (MemoryStream memoryStream = new MemoryStream())
{
image.Save(memoryStream, System.Drawing.Imaging.ImageFormat.Png);
memoryStream.Position = 0;
var bitmapImage = new BitmapImage();
bitmapImage.BeginInit();
memoryStream.Seek(0, SeekOrigin.Begin);
bitmapImage.StreamSource = memoryStream;
bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
bitmapImage.EndInit();
return bitmapImage;
}
}
Many other modifications were made to make the Ghostscrip.NET viewer work in my WPF MVVM app. If anybody is interested in more details, I will post more.
I am reading data from a smartcard.
This data contains a picture as well.
Code to get the picture in a class ReadData:
public Bitmap GetPhotoFile()
{
byte[] photoFile = GetFile("photo_file");
Bitmap photo = new Bitmap(new MemoryStream(photoFile));
return photo;
}
Code in the xaml:
imgphoto = ReadData.GetPhotoFile();
Error being generated:
Cannot implicitly convert type 'System.Drawing.Bitmap' to 'System.Windows.Controls.Image'
What is the best approach in this?
Do not create a System.Drawing.Bitmap from that file. Bitmap is WinForms, not WPF.
Instead, create a WPF BitmapImage
public ImageSource GetPhotoFile()
{
var photoFile = GetFile("photo_file");
var photo = new BitmapImage();
using (var stream = new MemoryStream(photoFile))
{
photo.BeginInit();
photo.CacheOption = BitmapCacheOption.OnLoad;
photo.StreamSource = stream;
photo.EndInit();
}
return photo;
}
Then assign the returned ImageSource to the Source property of the Image control:
imgphoto.Source = ReadData.GetPhotoFile();
I am trying to load an Image in Silverlight, but i keep getting a null pointer exception when i assign it to this.Image1.Source. I've looked over similiar stack questions, but none of them solve the problem. My image file is in a folder right next to the xap file.
public MainPage()
{
Uri uri = new Uri("Content/button.png", UriKind.Relative);
var image = new BitmapImage { UriSource = new Uri("Content/button.png", UriKind.Relative) };
try
{
BitmapImage img = new BitmapImage(uri);
this.image1.Source = image;
}
catch (Exception e)
{
string problem = e.Message;
}
InitializeComponent();
}
Ok, i've found the problem, i was trying to assign image to image1.Source, but image1 was not yet created - it is created in the InitilizeComponent() function.
In an app I need to serialize an image through a binarywriter, and to get it in an other app to display it.
Here is a part of my "serialization" code :
FileStream fs = new FileStream(file, FileMode.Create, FileAccess.Write);
BinaryWriter bin = new BinaryWriter(fs);
bin.Write((short)this.Animations.Count);
for (int i = 0; i < this.Animations.Count; i++)
{
MemoryStream stream = new MemoryStream();
BitmapEncoder encoder = new PngBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(Animations[i].Image));
encoder.Save(stream);
stream.Seek(0, SeekOrigin.Begin);
bin.Write((int)stream.GetBuffer().Length);
bin.Write(stream.GetBuffer());
stream.Close();
}
bin.Close();
And here is the part of my deserialization that load the image :
FileStream fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);
BinaryReader bin = new BinaryReader(fs);
int animCount = bin.ReadInt16();
int imageBytesLenght;
byte[] imageBytes;
BitmapSource img;
for (int i = 0; i < animCount; i++)
{
imageBytesLenght = bin.ReadInt32();
imageBytes = bin.ReadBytes(imageBytesLenght);
img = new BitmapImage();
MemoryStream stream = new MemoryStream(imageBytes);
BitmapDecoder dec = new PngBitmapDecoder(stream, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
img = dec.Frames[0];
stream.Close();
}
bin.Close();
When I use this method, I load the image (it seems to be stored in the "img" object) but it can't be displayed.
Has somedy an idea?
Thanks
KiTe
UPD :
I already do this : updating my binding, or even trying to affect it directly through the window code behing. None of these approaches work :s
However, when I add this :
private void CreateFile(byte[] bytes)
{
FileStream fs = new FileStream(Environment.CurrentDirectory + "/" + "testeuh.png", FileMode.Create, FileAccess.Write);
fs.Write(bytes, 0, bytes.Length);
fs.Close();
}
at the end of you function, it perfectly create the file, which can be read without any problems ... So I don't know where the problem can be.
UPD 2 :
A weird things happens.
Here is the binding I use :
<Image x:Name="imgSelectedAnim" Width="150" Height="150" Source="{Binding ElementName=lstAnims, Path=SelectedItem.Image}" Stretch="Uniform" />
(the list is itself binded on an observableCollection).
When I create manually the animation through the app, it works (the image is displayed).
But when I load it, it is not displayed (I look at my code, there are not any "new" which could break up my binding, since there are others properties binded the same way and they does not fail).
Moreover, I've put a breakpoint on the getter/setter of the properties Image of my animation.
When it is created, no problems, it has the good informations.
But when it is retreived through the getter, it return a good image the first time, and then and image with pixelWidth, pixelHeight, width, height of only 1 but without going through the setter anymore !
Any idea?
UPD3
tried what you said like this :
Added a property TEST in my viewModel :
private BitmapSource test;
public BitmapSource TEST { get { return test; } set { test = value; RaisePropertyChanged("TEST"); } }
then did it :
img = getBmpSrcFromBytes(bin.ReadBytes(imageBytesLenght));
TEST = img;
(in the code showed and modified before)
and my binding :
<Image x:Name="imgSelectedAnim" Width="150" Height="150" Source="{Binding Path=TEST}" Stretch="Uniform" />
(datacontext is set to my ViewModel)
And it still doesn't work and does the weird image modification (pixW, pixH, W and H set to 1)
FINAL UPD:
It seems I finally solved the problem. Here is simply what I did :
byte[] bytes = bin.ReadBytes(imageBytesLenght);
MemoryStream mem = new MemoryStream(bytes);
img = new BitmapImage();
img.BeginInit();
img.StreamSource = mem;
img.EndInit();
the strange thing is that it didn't work the first time, maybe it is due to an architectural modification within my spriteanimation class, but I don't think it is.
Well, thank you a lot to Eugene Cheverda for his help
At the first, I think you should store your images in a list of BitmapSource and provide reverse encoding of image for using stream as BitmapImage.StreamSource:
FileStream fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);
BinaryReader bin = new BinaryReader(fs);
int animCount = bin.ReadInt16();
int imageBytesLenght;
byte[] imageBytes;
List<BitmapSource> bitmaps = new List<BitmapSource>();
for (int i = 0; i < animCount; i++)
{
imageBytesLenght = bin.ReadInt32();
imageBytes = bin.ReadBytes(imageBytesLenght);
bitmaps.Add(getBmpSrcFromBytes(imageBytes));
}
bin.Close();
UPD
In code above use func written below:
private BitmapSource getBmpSrcFromBytes(byte[] bytes)
{
using (var srcStream = new MemoryStream(bytes))
{
var dec = new PngBitmapDecoder(srcStream, BitmapCreateOptions.PreservePixelFormat,
BitmapCacheOption.Default);
var encoder = new PngBitmapEncoder();
encoder.Frames.Add(dec.Frames[0]);
BitmapImage bitmapImage = null;
bool isCreated;
try
{
using (var ms = new MemoryStream())
{
encoder.Save(ms);
bitmapImage = new BitmapImage();
bitmapImage.BeginInit();
bitmapImage.StreamSource = ms;
bitmapImage.EndInit();
isCreated = true;
}
}
catch
{
isCreated = false;
}
return isCreated ? bitmapImage : null;
}
}
Hope this helps.
UPD #2
Your binding is incorrect. You may be should bind selected item to for example CurrentImageSource. And then this CurrentImageSource bind to Image control.
Code:
public class MyViewModel : INotifyPropertyChanged
{
public ObservableCollection<BitmapSource> ImagesCollection { get; set; }
private BitmapSource _currentImage;
public BitmapSource CurrentImage
{
get { return _currentImage; }
set
{
_currentImage = value;
raiseOnPropertyChanged("CurrentImage");
}
}
private void raiseOnPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
public event PropertyChangedEventHandler PropertyChanged;
}
Then:
<ListBox ItemsSource="{Binding ImagesCollection}" SelectedItem="{Binding CurrentImage}"/>
<Image Source="{Binding CurrentImage}"/>
ADDED
Here is the sample project in which implemented technique as I described above.
It creates animations collection and represent them in listbox, selected animation is displayed in Image control using its Image property.
What I want to say is that if you cannot obtain image as it should be, you need to search problems in serialization/deserialization.