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How can I create a signature capture in iPhone SDK?

d34thd34l34r
d34thd34l34r asked
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I have a requirement from a client where I need to capture the end users signature.  They will be signing with their finger.
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Commented:
Hand signature?
Read here about the iPhone touch screen:
http://electronics.howstuffworks.com/iphone1.htm

From my point of view, you cannot do it on the capacitive screen.
I think even on the Windows Mobile/CE device with the resistive screen there is a possibility to sign with the stylus and save the signature as an image.

Author

Commented:
Hand signature yes.  I am confident that it can be done simply because of the fact that I have seen applications that have this functionality ( apple's new checkout application at apple retail stores is one example ) but, unfortunately I don't even know where to begin.  You can draw images with various applications with your finger ( IE: Whiteboard ) on iphone and thus getting the first part of the equation out of the way however, your still left with saving that as an image and serializing it up to a server somewhere for safekeeping.  If I can get help with how to draw on the iphone with your finger, I think thats a good start / direction.  Thanks for your help!

Commented:
I will not believe till will not see it myself. :)
Try to touch the screen with a stylus - you need that to sign something, it's not about a finger. You will see the phone does not react at all.


Author

Commented:
When i bought my ipad @ apple i used my finger to sign it on an ipod touch.  Stylus for sure wont work but your finger will...

Commented:
Ok.
I imagine how my signature may look if I will make it with my finger. :) And it is a bit funny if I see my neighbor (a sportsman like Steven Seagal) signing with his finger something on iPhone.
Commented:
On WWDC people talked about a serious improvements in the gesture recognition on iPhone 4.
You can find a code (current SDK) here:
http://www.iphonedevsdk.com/forum/iphone-sdk-development/6711-gesture-recognition.html

Commented:
You say that the link I posted for you:
http://www.iphonedevsdk.com/forum/iphone-sdk-development/6711-gesture-recognition.html
was useless and you didn't take the idea from there.

I do not think that it is a right decision simply to close the question.

Commented:
I think it is a bad idea to sign something on the iPhone screen. From my point of view http://#a32997191.

It is possible to draw on the screen with the finger and the comment http://#a32997495 shows to recognizes the gestures. This comment helped to d34thd34l34r to find another link (comment http://#a32998059) that contains less technical details that the one I posted.

Author

Commented:
Bad idea or Good idea, if a client wants to pay good money for the iphone to do back flips, and we can write code to make it do that then I think we do it ( after expressing concerns / suggestions ).  I respect you opinion however, I think that if the apple retail stores are using finger signatures on their POS ipod touches when they check you out, then there is definitely some type of validity to it.  :)  Actually, your link did not help me find anything however, for your efforts, I will award you the points!

Author

Commented:
The answer was not exactly what I was looking for.

Commented:
>>Bad idea or Good idea, if a client wants to pay good money
You are right here.
But not here:
>>Actually, your link did not help me
 Check the link: http://www.iphonedevsdk.com/forum/iphone-sdk-development/6711-gesture-recognition.html
It contains the code you found later and more.
Good luck. Thanks.
 

Author

Commented:
Maybe i should read the full post rather than browse only the top part of the article, my mistake.... :(  

Commented:
The comment selected as the accepted solution now (with grade C) shows how to detect the gestures - the points where the suer touches the screen and how his finger is moving. So it is possible to draw the path already.
To say that it can be a signature.... Again, it is the capacitive screen. So ... I do not know how it will be possible to identify that this is my signature.