UIButton

    // 设置按钮的文字
    showTextButton.titleLabel.numberOfLines = 0;
    [showTextButton setTitle:self.message.text forState:UIControlStateNormal];
    
    // 强制更新
    [showTextButton layoutIfNeeded];
    
    // 设置按钮的高度就是titleLabel的高度
    [showTextButton updateConstraints:^(MASConstraintMaker *make) {
        CGFloat buttonH = showTextButton.titleLabel.frame.size.height;
        make.height.equalTo(buttonH);
    }];
    
    // 强制更新
    [showTextButton layoutIfNeeded];

按钮的基本属性
[btnChooseBank setTitleEdgeInsets:UIEdgeInsetsMake(0, 7, 0, 0)];//距离左边7个距离
btnChooseBank.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft;//文字靠右