objective c - Objects not initialized -


in objective c, can following 

uiimage *myimage = [uiimage imagenamed:@"myphoto.jpg"]; variable.image = myimage;

and works fine. object named "myimage" never initialized, , uiimage never had memory allocated , yet code still works..

can explain what's going on here?

yes, object initialised. imagenamed: method allocates , initialises object, sends autorelease message, returns memory address you. store memory address in pointer called myimage.

myimage , object 2 different things. myimage merely points @ memory location. not object itself.

you can pass around objects without assigning them variables, , can assign 1 object many variables.

consider this:

uiimage *imageone; uiimage *imagetwo;  imageone = [uiimage imagenamed:@"myphoto.jpg"]; imagetwo = imageone;

the image wasn't copied. there 1 object in existence. both variables point it.

now consider this:

nslog(@"%@", [uiimage imagenamed:@"myphoto.jpg"]);

you didn't assign variable. object still existed, right?


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