Objective-C中的标签文本

Question

I have problem about Label.Test

CGRect frame = _gobutton.frame;
frame.origin.x=rand()%330+1;
frame.origin.y=rand()%550+1;
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.3];
_gobutton.frame = frame;
[UIView commitAnimations];

i=i+1;

self.score.Text = [NSString stringWithFormat:@"%i",i];

I'm trying to move the button around the screen and when I click the button show the score in the label. Currently, when I click the button the score increases but my button moves back to its original locations.

How do I fix this?

Answer 1

The code you posted should animate your button to a new location. As holex says in his comment, you should really be using the newer methods like animateWithDuration:animations: and its variants.

If you are using auto-layout (the default or XIB files and storyboards in Xcode 5 and later) then you can't animate a view (or, which is a type of view) by moving it's frame. Instead you need to use position constraints, attach outlets to the constraints, and change the constraint's constant values.

If you want to animate the frame, you need to turn off auto-layout on your XIB/Storyboard and use the older struts and springs style resizing.

Answer 2

Since you are using the storyboard with auto-layout it will always return to its position. If you plan on animating a view I would create it programmatically.

    _gobutton = [[UIButton alloc] initWithFrame:CGRectMake(buttonX, buttonY, buttonWidth, buttonHeight)];

     [_gobutton addTarget:self action:@selector(yourButtonSelector:) forControlEvents:UIControlEventTouchUpInside];

     [_gobutton setBackgroundImage:[UIImage imageNamed:@"aphoto"] forState:UIControlStateNormal];

     [self.view addSubview:_gobutton];

Just take the button off of the storyboard and create your button like that. You will be able to move it anywhere you want. Its easier then changing the storyboard constraints programmatically.