iphone - 尝试将 CGrect 传递给 PerformSelector withObject

Question

我正在尝试传递 CGRect:

SEL frameSel = NSSelectorFromString(@"setFrame:");
CGRect rect = CGRectMake(10, 10, 200, 100);
[object performSelector:frameSel withObject:rect ];

但这不能编译

我也尝试过:

SEL frameSel = NSSelectorFromString(@"setFrame:");
CGRect rect = CGRectMake(10, 10, 200, 100);
NSValue * value = [NSValue valueWithCGRect:rect];
[object performSelector:frameSel withObject:value ];

实际上，这确实可以编译，但是当我调试时，框架设置不正确:

po object
<UILabel: 0x39220f0; frame = (0 0; 200 100); text = 'reflectionLabel'; clipsToBounds = YES; userInteractionEnabled = NO; layer = <CALayer: 0x3922240>>

但应该是frame = (10 10; 200 100)

如何解决这个问题？

提前谢谢您!

Answer 1

CGRect rect = CGRectMake(10, 10, 200, 100);
[object performSelector:frameSel withObject:rect ];

But this does not compile

正确，因为 rect 是一个结构，而不是指向对象的指针。

CGRect rect = CGRectMake(10, 10, 200, 100);
NSValue * value = [NSValue valueWithCGRect:rect];
[object performSelector:frameSel withObject:value ];

Actually, this does compile but when I debug, the frame is not setted correctly:

po object
<UILabel: 0x39220f0; frame = (0 0; 200 100); text = 'reflectionLabel'; clipsToBounds = YES; userInteractionEnabled = NO; layer = <CALayer: 0x3922240>>

嗯，这不是垃圾，所以看起来它是有效的，尽管原点不知何故仍然为零。您可能想就此提出一个单独的问题。

无论如何，你为什么要使用performSelector:withObject:？您不会将其发送给特定的线程，也不会延迟它；为什么不简单地说object.frame = rect？