UIButton 交换位置

CGFloat space = 3;
    _nameBtn.titleEdgeInsets = UIEdgeInsetsMake(0, - _nameBtn.imageView.v_width - space, 0, _nameBtn.imageView.v_width +space);
    _nameBtn.imageEdgeInsets = UIEdgeInsetsMake(0,_nameBtn.titleLabel.v_width + space, 0, - _nameBtn.titleLabel.v_width - space);