At this point it is worth mentioning that actually in
DELPHI XE10 IOS9 HOW TO
QR Codes generation in FireMonkey – both desktop and mobile!ĭownload the FMX version of DelphiZXIngQRCode.pas: FMX-DelphiZXIngQRCodeĬomments are welcome (even more if you know how to resize a bitmap in FireMonkey on mobile without antialiasing)! On FireMonkey Mobile it does not 🙁 – the resized image is still blurred (antialiasing used). In a FireMonkey Desktop application, this works as expected. ImgQRCode.WrapMode := TImageWrapMode.iwStretch
DELPHI XE10 IOS9 CODE
There are two properties you need to set to ensure a bigger copy of your (small) qr code is drawn pixel-copy-perfect. (QRCodeBitmap, rSrc, rDest, 1) īy default, in FMX, when using DrawBitmap to resize it, antialiasing is used by default. RSrc := TRectF.Create(0, 0, QRCodeBitmap.Width, QRCodeBitmap.Height) (QRCodeBitmap.Width, QRCodeBitmap.Height) Using TImage, the code to get/display the generated QR Code is as follows: I’ve decided to use TImage and not TPaintBox as I was simply not able to make TPictureBox in FireMonkey draw what I wanted 🙁 So I had to play a little until I was able to make it work correctly. StretchDraw by default does no antialiasing. There’s no StrecthDraw in FMX’s Canvas class. VCL’s Canvas.StretchDraw to FMX’s Canvas.DrawBitmap Note: compare this with the VCL approach of TDelphiZXingQRCode usage. refresh image control imgQRCode is a TImage VBitMapData.SetPixel(Column, Row, pixelColor) If QRCodeBitmap.Map(TMapAccess.maWrite, vBitMapData) then QRCodeBitmap.SetSize(QRCode.Rows, QRCode.Columns) QRCode.QuietZone := StrToIntDef(edtQuietZone.Text, 4) QRCode.Encoding := TQRCodeEncoding(cmbEncoding.ItemIndex) Once the qr code is generated, to convert it to a bitmap image, in FireMonkey: In FireMonkey this is not supported and you have to use the SetPixel property of a TBitmapData instance. In the VCL, the TCanvas class allows accessing single pixels through the “Canvas.Pixels()” property. Single Pixel Drawing (and Other Canvas Drawing) FireMonkey Style Therefore, the second change to the unit would be to replace “widestring” with “string” and “ansistring” with “array of byte” (or something else as explained in the article). More info here: Migrating Delphi Code to Mobile from Desktop. If you want to go mobile, those are not supported and you should use “string”. This also requires to make changes like: from “Blocks: TObjectList ” to “Blocks: TObjectList ” – that is to use strongly typed generics list classes.įurther, there are lots of “ansistring” and “widestring” types used for parameters in various functions inside the unit. Therefore, the first change is to replace “uses contnrs, …” with “uses, …” Under FireMonkey for mobile, more specifically under ARC, the classes contained in cannot be used because they are not ARC compliant.Įquivalent classes are to be found in (ARC compliant) where generics versions of TObjectList is defined. The unit uses “ contnrs” () unit which implements TObjectList (used by the unit) and other container like classes. To FireMonkey-enable the DelphiZXingQRCode unit a few changes to the source code were required. While the DelphiZXingQRCode was designed to support VCL applications (and be used in newer as well as in older Delphi versions), it can also easily be “upgraded” for Fire Monkey applications – be it desktop or mobile (Android, iOS). The DelphiZXingQRCode unit, ported from ZXing by Debenu, allows to easily add QR Code generation to your Delphi VCL applications.
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