button的内边距

UIImage *buttonImage = [UIImage imageNamed:@"Xcode"];

 CGFloat buttonImageViewWidth = CGImageGetWidth(buttonImage.CGImage);

 CGFloat buttonImageViewHeight = CGImageGetWidth(buttonImage.CGImage);

 if ([UIScreen mainScreen].scale == 2.0f) {// iOS 4.0+

     buttonImageViewWidth *= 0.5f;

     buttonImageViewHeight *= 0.5f;

 }

 NSString *buttonTitle = @"中华人民共和国";

 UIFont *buttonTitleFont = [UIFont systemFontOfSize:17.0f];

 CGSize buttonTitleLabelSize = [buttonTitle sizeWithFont:buttonTitleFont];

 // button宽度,至少为imageView宽度与titleLabel宽度之和

 CGFloat buttonWidth = buttonImageViewWidth + buttonTitleLabelSize.width;

 // button高度,至少为imageView高度与titleLabel高度之和

 CGFloat buttonHeight = buttonImageViewHeight + buttonTitleLabelSize.height;

 

 UIButton *b = [[UIButton alloc] init];

 [b setCenter:CGPointMake(160, 160)];

 [b setBounds:CGRectMake(0, 0, buttonWidth, buttonHeight)];

 [b.titleLabel setFont:buttonTitleFont];

 [b setBackgroundColor:[UIColor redColor]];

 

 [b setImage:buttonImage forState:UIControlStateNormal];

 [b.imageView setBackgroundColor:[UIColor greenColor]];

 

 [b setTitle:buttonTitle forState:UIControlStateNormal];

 [b setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];

 [b setTitleColor:[UIColor scrollViewTexturedBackgroundColor] forState:UIControlStateHighlighted];

 [b.titleLabel setBackgroundColor:[UIColor whiteColor]];

 

 [self.view addSubview:b];

 

 CGPoint buttonBoundsCenter = CGPointMake(CGRectGetMidX(b.bounds), CGRectGetMidY(b.bounds));

 // 找出imageView最终的center

 CGPoint endImageViewCenter = CGPointMake(buttonBoundsCenter.x, CGRectGetMidY(b.imageView.bounds));

 // 找出titleLabel最终的center

 CGPoint endTitleLabelCenter = CGPointMake(buttonBoundsCenter.x, CGRectGetHeight(b.bounds)-CGRectGetMidY(b.titleLabel.bounds));

 // 取得imageView最初的center

 CGPoint startImageViewCenter = b.imageView.center;

 // 取得titleLabel最初的center

 CGPoint startTitleLabelCenter = b.titleLabel.center;

 // 设置imageEdgeInsets

 CGFloat imageEdgeInsetsTop = endImageViewCenter.y - startImageViewCenter.y;

 CGFloat imageEdgeInsetsLeft = endImageViewCenter.x - startImageViewCenter.x;

 CGFloat imageEdgeInsetsBottom = -imageEdgeInsetsTop;

 CGFloat imageEdgeInsetsRight = -imageEdgeInsetsLeft;

 b.imageEdgeInsets = UIEdgeInsetsMake(imageEdgeInsetsTop, imageEdgeInsetsLeft, imageEdgeInsetsBottom, imageEdgeInsetsRight);

 // 设置titleEdgeInsets

 CGFloat titleEdgeInsetsTop = endTitleLabelCenter.y-startTitleLabelCenter.y;

 CGFloat titleEdgeInsetsLeft = endTitleLabelCenter.x - startTitleLabelCenter.x;

 CGFloat titleEdgeInsetsBottom = -titleEdgeInsetsTop;

 CGFloat titleEdgeInsetsRight = -titleEdgeInsetsLeft;

 b.titleEdgeInsets = UIEdgeInsetsMake(titleEdgeInsetsTop, titleEdgeInsetsLeft, titleEdgeInsetsBottom, titleEdgeInsetsRight);

 [b release];