iOS Code Snippet Generate QR Codes

Based on http://stackoverflow.com/questions/12051118/is-there-a-way-to-generate-qr-code-image-on-ios

Code:

Dim NativeMe As NativeObject = Me
NativeMe.RunMethod("createQRForString::", Array ("Your text",ImageView1))


#If OBJC
- (void)createQRForString:(NSString *)qrString :(UIImageView *)qrImageView
{
  // Need To convert the string To a UTF-8 encoded NSData object
  NSData *stringData = [qrString dataUsingEncoding: NSISOLatin1StringEncoding];

  // Create the filter
  CIFilter *qrFilter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
  // Set the message content And error-correction level
  [qrFilter setValue:stringData forKey:@"inputMessage"];
  [qrFilter setValue:@"M" forKey:@"inputCorrectionLevel"];
 
   // Remove blur effect with scaling
   CGAffineTransform transform = CGAffineTransformMakeScale(100.0f,100.0f);
   CIImage *qrOutput = [qrFilter.outputImage imageByApplyingTransform: transform];

   //Convert CIImage to UIImage
   UIImage *qrImage = [[UIImage alloc] initWithCIImage:qrOutput];
 
   //Set Image to ImageView
   [qrImageView setImage:qrImage];
}
#End If

 

[f0raster0]

JanPro, I was looking for it..Thanks.

I have attached a simple example

 

[Humberto]

I´m trying to save to a file the Qrcode generated , and send it by mail.

Any other image I can save and send but the qrcode.

I can copy the image to other imageview but when I save it to a file nothing is seeing as attachemnet in an email

code to generate

    NativeMe.RunMethod("createQRForString::", Array (b,Im_QrCode))

Then to read the bitmap and save to a file and send

    Dim Bm As Bitmap
    Bm = Im_QrCode.Bitmap
   
    Dim Out As OutputStream
    Out = File.OpenOutput(File.DirTemp, "Im_QrCode.png", False)
    Bm.WriteToStream(Out, 100, "PNG")
    Out.Close

'    'Enviar email
    Dim xList As List
    xList.Initialize
    SendMail ( xList, "QrCode gerado por QrCode HSP", "A imagem em anexo foi gerada pelo programa QrCode HSP " ,File.DirTemp , "Im_QrCode.png", "image/png" ) '"image/jpg" ) ' "image/png" )

If I copy any other image to Im_QrCode.png the image is sent

File.Copy  (File.DirAssets, "money1.png", File.DirTemp , "Im_QrCode.png")

 

[JanPRO]

I don't know why it doesn't work. However try this:

    CreateQr("test",Null,File.DirDocuments,"test.png")
    Sub CreateQr(Text As String, IV As ImageView,Dir As String, PNGName As String)
    Dim NativeMe As NativeObject = Me
    Dim QRImage As Bitmap = NativeMe.RunMethod("createQRForString:", Array (Text))
   
    If IV.IsInitialized Then IV.Bitmap = QRImage
   
    Dim pn As Panel
    pn.Initialize("")
    pn.Height = QRImage.Height
    pn.Width = QRImage.Width
   
    Dim Dest As Rect
    Dest.Initialize(0,0,QRImage.Width,QRImage.Height)
   
    Dim Ca As Canvas
    Ca.Initialize(pn)
    Ca.DrawBitmap(QRImage,Dest)
    Ca.Refresh
   
    Dim Out As OutputStream
    Out = File.OpenOutput(Dir, PNGName,False)
    Ca.CreateBitmap.WriteToStream(Out, 100,"PNG")
    Out.Close
   
    #If OBJC
        - (UIImage *)createQRForString:(NSString *)qrString
        {
          // Need To convert the string To a UTF-8 encoded NSData object
          NSData *stringData = [qrString dataUsingEncoding: NSISOLatin1StringEncoding];

          // Create the filter
          CIFilter *qrFilter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
          // Set the message content And error-correction level
          [qrFilter setValue:stringData forKey:@"inputMessage"];
          [qrFilter setValue:@"M" forKey:@"inputCorrectionLevel"];
        
           // Remove blur effect with scaling
           CGAffineTransform transform = CGAffineTransformMakeScale(100.0f,100.0f);
           CIImage *qrOutput = [qrFilter.outputImage imageByApplyingTransform: transform];

           //Convert CIImage to UIImage
           UIImage *qrImage = [[UIImage alloc] initWithCIImage:qrOutput];
          
           return qrImage;
        }
    #End If
End Sub

 

[Humberto]

Hi JanPro
This works, but I´m sending the print screen of the image and not the original image.

I Tryed to save the original bitmap to a file and doesn´t work either., instead of get the bitmap from the imageview

 

[JanPRO]

but I´m sending the print screen of the image and not the original image.

Not sure what you mean by that. Can you explain it?

Jan

 

[Humberto]

The imageview is set to fill the image in and maybe is not the original size ( height and width ) so when I capture the printscreen it´s not the original picture.

I don´t know why this bitmap can not be saved in a file. I can copy this bitmap to other imageview. Another picture loaded to an imageview can be saved to a file.

In B4A works.

How can I see the file in IPhone ?

 

[JanPRO]

But the Bitmap property of the ImageView returns always the "original image".

 

[Humberto]

Yes, but what I understand from your code is that you capture the screen image and save to a file.

Is why I´m trying to get from imageview.bitmap

 

[JanPRO]

Yes, but what I understand from your code is that you capture the screen image and save to a file.

Yes, and the result bitmap will be visual the same like the bitmap from the imageview, so I don't understand your problem.

Jan

 

[Humberto]

I don´t know if I´m wrong, but the result will depend of the size of the imageview in the panel, as I use "fill" property it´s adjust the image original.

The orginalmimage is bigger that one displayed

 

[JanPRO]

as I use "fill" property it´s adjust the image original

Yes, but only visual. A ImageView doesn't resize it's bitmap.

 

[Humberto]

I don´t know if I´m wrong

Your code draw a rect with the image inside, from now the originalmimage is gone and we have a rect with an image adjusted to that size.

When we save it, is a different image.

Right?

 

[JanPRO]

When we save it, is a different image.

Right?

Yes, but you can't see a difference.