UIButton setTitleColor:forState:问题 [英] UIButton setTitleColor:forState: question

问题描述

以下代码为什么起作用...

Why does the following code work...

[signInBtn setTitleColor:[UIColor blackColor] forState:UIControlStateHighlighted];
[signInBtn setTitleColor:[UIColor blackColor] forState:UIControlStateDisabled];

这不是吗?

[signInBtn setTitleColor:[UIColor blackColor] forState:UIControlStateHighlighted|UIControlStateDisabled];

推荐答案

我知道这是一个老问题，但是这些答案不正确.

I know this is an old question, but these answers aren't correct.

分别设置每个变量时，都是说state属性应为UIControlStateHighlighted或UIControlStateDisabled，但不能同时为这两个

When you set each separately you are saying the state property should be UIControlStateHighlighted OR UIControlStateDisabled but NOT both

当按位或它们一起表示要在state属性中同时设置它们时.含义UIControlStateHighlighted和UIControlStateDisabled在state属性中设置.

When you bitwise or them together you are stating they must BOTH be set in the state property. Meaning UIControlStateHighlighted AND UIControlStateDisabled are set in the state property.

下面的示例代码完美地说明了我的观点.如果您不同意自己运行它.

The example code below perfectly illustrates my point. If you disagree run it for yourself.

[button setTitle:@"highlighted and selected" forState:UIControlStateHighlighted | UIControlStateSelected];
[button setTitle:@"Highlighted only" forState:UIControlStateHighlighted];
[button setTitle:@"Selected only" forState:UIControlStateSelected];
[button setTitle:@"Normal" forState:UIControlStateNormal];

NSLog(@"Normal title: %@", [[button titleLabel] text]); // prints title: Normal

[button setSelected:YES];

NSLog(@"Selected title: %@", [[button titleLabel] text]); // prints title: Selected only 

[button setSelected:NO];
[button setHighlighted:YES];

NSLog(@"highlighted title: %@", [[button titleLabel] text]); // prints title: Highlighted only

[button setSelected:YES];

NSLog(@"highlighted and selected title: %@", [[button titleLabel] text]); // prints title: highlighted and selected

这篇关于UIButton setTitleColor:forState:问题的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！