经过一下午的查阅资料及尝试,最终解决了在图片和文字垂直排列的情况下,如果文字长度变化会导致图片位置变动的问题,最开始采用了网上比较多的做法,做法如下:
c
@interface UIButton (UIButtonExt) - (void)centerImageAndTitle:(float)space; - (void)centerImageAndTitle; @end @implementation UIButton (UIButtonExt) - (void)centerImageAndTitle:(float)spacing { // get the size of the elements here for readability CGSize imageSize = self.imageView.frame.size; CGSize titleSize = self.titleLabel.frame.size; // get the height they will take up as a unit CGFloat totalHeight = (imageSize.height + titleSize.height + spacing); // raise the image and push it right to center it self.imageEdgeInsets = UIEdgeInsetsMake(- (totalHeight - imageSize.height), 0.0, 0.0, - titleSize.width); // lower the text and push it left to center it self.titleEdgeInsets = UIEdgeInsetsMake(0.0, - imageSize.width, - (totalHeight - titleSize.height),0.0); } - (void)centerImageAndTitle { const int DEFAULT_SPACING = 6.0f; [self centerImageAndTitle:DEFAULT_SPACING]; } @end
后面经过测试,如果button的文字长度变更,会导致图片位置变化,经过多次修改UIEdgeInsets的值也没有达到期望效果,最终采用集成UIButton类,重写layoutSubviews函数实现,特将成果记录一下,以便后续查阅
c
-(void)layoutSubviews { [super layoutSubviews]; // Center image CGPoint center = self.imageView.center; center.x = self.frame.size.width/2; center.y = self.imageView.frame.size.height/2; self.imageView.center = center; //Center text CGRect newFrame = [self titleLabel].frame; newFrame.origin.x = 0; newFrame.origin.y = self.imageView.frame.size.height + 5; newFrame.size.width = self.frame.size.width; self.titleLabel.frame = newFrame; self.titleLabel.textAlignment = UITextAlignmentCenter; }