UIButton setTitle：forState：question

本文介绍了UIButton setTitle：forState：question的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

为什么下面的代码工作：

Why does the following code works:

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

，但这不会：

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

推荐答案

我知道这是一个老问题，不正确。

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

当你单独设置每一个时，你说 state 属性应该 UIControlStateHighlighted OR UIControlStateDisabled 但不是两者

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

当你按位或他们在一起你说他们必须BOTH在状态属性中设置。在状态属性中设置含义 UIControlStateHighlighted AND UIControlStateDisabled

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。

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