Forum > IWSignaturePad demo generates an error

07-27-2022, 02:52 PM:

Hi Alexandre,

Tested IWSignaturePad for the first time but see an DevTools console error.

Code:

(index):53 Uncaught TypeError: Cannot read properties of null (reading 'getContext')

at Initialize ((index):53:15)

at HTMLDocument.<anonymous> ((index):98:23)

var c=IW.$("").getContext("2d");c.fillStyle="#FFFFFF";

The property HTMLName for the control is empty in TIWCustomCanvas.AddContext() when called from TIWCustomCanvas.InitControl()

Tested with IW15.2.64 running Chrome.

Update: Also when using the upload button on a 'big or complex' signature, the exception EIdReadLnMaxLineLengthExceeded is raised.

07-28-2022, 04:41 AM:

Thanks for reporting this.

The JS error has been fixed, and the Indy issue needs to be configured accordingly:

program IWSignaturePad;

uses

IWRtlFix,

IWStart,

InIOHandler, // <- add this unit

Unit27 in 'Unit27.pas' {IWForm27: TIWAppForm},

ServerController in 'ServerController.pas' {IWServerController: TIWServerControllerBase},

UserSessionUnit in 'UserSessionUnit.pas' {IWUserSession: TIWUserSessionBase};

{$R *.res}

begin

IdMaxLineLengthDefault := 128 * 1024; // <- Increase to something like 64 or 128 kb

TIWStart.Execute(True);

end.