Question

for this line:

[UISwitch setOn:YES animated:YES];

Xcode gives me a warning “class method not found (return type defaults to ‘id’).”

When I click on setOn or animated, the utilities pane recognizes it and says its declared in UIKit/UISwitch.h

UIKit is in my frameworks folder. I imported the .h to the .m like this:

#import "UIKit/UISwitch.h"

When I run, the main function receives “SIGABRT”

But when I remove that line above, no problems.

Answer 1

This is because setOn:animated is not a class method. It is an instance method. You have to call this on an instance of UISwitch. For example:

// create an instance of UISwitch and add it to our view
UISwitch *onoff = [[[UISwitch alloc] init] autorelease];
[self.view addSubview:onoff];

[onoff setOn:YES animated:YES]; // should work normally