For ios, the question about passing parameters in the selector event seems simple but confusing (resolved). iosselector

For ios, the question about passing parameters in the selector event seems simple but confusing (resolved). iosselector

Recently, when using selector,

Add a click event to UIButton. You can add ":" After selector to pass the button as a parameter to the method,

Use today

[NSTimerscheduledTimerWithTimeInterval: 1 target: selfselector: @ selector (rotateAction :) userInfo: nilrepeats: NO];

Write a method

# Pragma mark-rotateAction

-(Void) rotateAction :( ViewController *) controller {

// UIView * view = [controller. view. subviews lastObject];

NSLog (@ "% @", controller );

// View. backgroundColor = [UIColor yellowColor];

}

Similar Writing seems to be unable to obtain self (controller). I printed the self and controller results and found that the address is different, so it is definitely not an object. I am thinking about why, check the printed results and find out the problem.

15:35:22. 806 testAffine Transformation[10698: 1998925] <ViewController: 0x7ff64db38a50>

15:35:23. 807 testAffine Transformation[10698: 1998925] <__nscftimer: 0x7ff64d8486d0>

Obviously they are not the same class, so the parameters passed by selector are: Click Event callers such as button, slider, progress, nstimer, etc.