我已经做了一个Swift扩展来做这个:

extension UIButton {
    func setTitleWithoutAnimation(title: String?) {
        UIView.setAnimationsEnabled(false)

        setTitle(title, forState: .Normal)

        layoutIfNeeded()
        UIView.setAnimationsEnabled(true)
    }
}

适用于我的iOS 8和9，与UIButtonTypeSystem。

(代码是Swift 2, Swift 3和Objective-C应该类似)

具有系统类型的UIButton在setTitle(_:for:)上有隐式动画。你可以用两种方法来解决这个问题:

设置按钮类型为自定义，从代码或接口生成器:

let button = UIButton(type: .custom)

从代码中禁用动画:

UIView.performWithoutAnimation {
    button.setTitle(title, for: .normal)
    button.layoutIfNeeded()
}

Swift 4版Xhacker刘回答

import Foundation
import UIKit
extension UIButton {
    func setTitleWithOutAnimation(title: String?) {
        UIView.setAnimationsEnabled(false)

        setTitle(title, for: .normal)

        layoutIfNeeded()
        UIView.setAnimationsEnabled(true)
    }
} 

请注意:

当_button的"buttonType"为"UIButtonTypeSystem"时，以下代码无效:

[UIView setAnimationsEnabled:NO];
[_button setTitle:@"title" forState:UIControlStateNormal];
[UIView setAnimationsEnabled:YES];

当_button的"buttonType"为"UIButtonTypeCustom"时，上述代码有效。

我已经做了一个Swift扩展来做这个:

extension UIButton {
    func setTitleWithoutAnimation(title: String?) {
        UIView.setAnimationsEnabled(false)

        setTitle(title, forState: .Normal)

        layoutIfNeeded()
        UIView.setAnimationsEnabled(true)
    }
}

适用于我的iOS 8和9，与UIButtonTypeSystem。

(代码是Swift 2, Swift 3和Objective-C应该类似)

结合以上的答案，可以为UIButtonTypeSystem提供以下解决方案:

if (_button.enabled)
{
    [UIView setAnimationsEnabled:NO];
    [_button setTitle:@"title" forState:UIControlStateNormal];
    [UIView setAnimationsEnabled:YES];
}
else // disabled
{
    [UIView setAnimationsEnabled:NO];
    _button.enabled = YES;
    [_button setTitle:@"title" forState:UIControlStateNormal];
    _button.enabled = NO;
    [UIView setAnimationsEnabled:YES];
}