IPhone SDK - Drawing images

Question

Hello.
I'm a beginner in Cocoa and Objective-C programming.
I have to develop an application where I have to draw a map (a simple JPEG image) on the screen. I want to be able to zoom in and out on that map and to be able to move on that map by moving a finger on the screen.
My image is a UIImage object.
I tried two methods :
- I created an UIImageView initialized with a CGRect (with its bounds corresponding to where I wanted to draw my image) and I added that UIImageView to my main view.
It works well but when I want to zoom or to move on my image, I have to recreate always a new UIImageView with the new bounds, which uses a lot of resources.
- I tried to override the drawRect method and in that method I tried to draw my image by using its drawInRect method with the CGRect object but it doesn't seem to have the same effect as creating an UIImageView with the same CGRect : the image is not resized to fill the rectangle.
Could someone help me to understand that please ?
Thank you.
Patrick Schevenels.

Answer 1

Thank you. I didn't know that property because it didn't appear in the code completion suggestions.
Now, I still have a little problem : when I handle the touch events with the following code, I have a vibration effect on my image when I move it :
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [[event allTouches] anyObject];
ancienpoint=touch.locationInView;
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [[event allTouches] anyObject];
nouveaupoint=touch.locationInView;
facteuroriginehorizontale += nouveaupoint.x-ancienpoint.x;
facteurorigineverticale += nouveaupoint.y-ancienpoint.y;
[self rafraichissement];
ancienpoint=nouveaupoint;
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
"rafraichissement" is the name of the method to refresh the screen where I create a new CGRect with the new bounds (I add facteuroriginehorizontale to the previous x and facteurorigineverticale to the previous y) and I change the frame property of my image view.
Thank you for your answer.
Patrick Schevenels.
Message was edited by: pscheven