I am not quite sure whether it is beneficial to draw the visual elements of my app with Core Graphics instead of providing the images. In terms of memory preservation and runtime speed which way is better ?
Share
Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
I am not quite sure whether it is beneficial to draw the visual elements of my app with Core Graphics instead of providing the images. In terms of memory preservation and runtime speed which way is better ?
+UIImage:imageNamed:is most efficient. It caches images, i.e. only one copy of an image is in memory and the image is decoded (from its PNG, JPEG, TIFF, etc. data) when it is needed and kept around for future reuse. If you are worried about memory use, iOS will purge theUIImagecache if you are running low or go into the background.Using Core Graphics to draw an image does not do any caching for you, unless you write the code to draw your image into a context, save the context as a bitmap, cache the bitmap and then reuse it later on. So you end up drawing the same thing over and over every time it is needed. For example, if you override UIView’s
-drawRect:to draw imagery, then during animations it will be called for every single frame (60 times a second). This needlessly burns CPU cycles and battery life.Bottom line is it depends on what your app is and does.