Drawing in a Custom iPhone View Part 3

The final installment of the three part series of destructive drawing in a custom UIView with ones finger. This part fills out the remainder of the touches based event methods. The first 5 minutes covers that portion - the remainder is for migrating the common code in the various touches methods into a separate method to make modification easier.

The project source code can be downloaded from here: http://www.ramicom.com/nethfel/iOS/FingerDrawing.zip

Category:

Howto & Style

Tags:

• iPhone
• iPad
• iPod
• touch
• drawing
• uiview
• developer
• development
• iOS
• xcode
• xcode4
• app
• objectivec
• apple

[peterrory]

it's not liking this and keeps throwing up an error saying lvalue required as left operand of assignment? I've kinda seen the problem the "location" dose not like the currentLoc.location - it wouldn't work. So I got rid of the dot notation and incorporated the [] and then I was getting the right colour of the "location" but now I get this error! I'll prob sort this but if u do read this (anyone) and understand the prob straight away, pls just point me in the right direction. Thank you.

[Nethfel]

@peterrory Without seeing your code, it's impossible to tell what's going wrong. The way it was written it works, if you'd like to send me a private message you can email me the code and I might be able to speak on it more intelligently. Unfortunately, it's like saying there's something wrong with my car to a mechanic - he/she can't do anything about it without examining it :)

[necromalice]

i got a question for ya... using this method,,,can I have more then one,,, touchesBegan etc??? perhaps in my FirstViewController.m ?? If I have all the touches in there regarding different instructions,, will these cause it to crash?

[Nethfel]

@necromalice I'm not sure I completely follow? More then one for a single view, or multiple views responding to touches based methods?

[necromalice]

@Nethfel I was refering to more then one view,,, each with their own instructions on Touches.

[Nethfel]

@necromalice Shouldn't be an issue - the only time it really might be an issue is if you stack the views in a hierarchy and don't implement all of the touches methods and/or pass some of those touches up the responder chain (like you implement touchesBegan and touchesEnded but not touchesMoved or touchesCanceled).

[mmoshaya]

Great tutorial. I like the additional part on how not to duplicate code. Thanks and keep them coming

[necromalice]

@Nethfel Thanks... good tutorial by the way.. though you are using xcoe 4 im running xcode 3.2.? lol

[aelk94]

@Nethfel Could you possibly post a link with the source code for the non-destructive drawing? I would greatly appreciate it because I could really use the reference for on an app I am currently working on.

[Nethfel]

@cdolan135 The code is done (actually it was done prior to me doing the destructive drawing tutorial), unfortunately the month of June got jammed with stuff I needed to take care of that prevented me from completing the actual screencasts. I hope to be able to start them again the week after the 4th now that my life has calmed down a bit :)