typedef struct UIEdgeInsets {  CGFloat top, left, bottom, right; // specify amount to inset (positive) for each of the edges. values can be negative to 'outset'} UIEdgeInsets;

@property(nonatomic)     UIEdgeInsets contentEdgeInsets UI_APPEARANCE_SELECTOR; // default is UIEdgeInsetsZero@property(nonatomic)     UIEdgeInsets titleEdgeInsets;        // default is UIEdgeInsetsZero@property(nonatomic)     BOOL     reversesTitleShadowWhenHighlighted; // default is NO. if YES, shadow reverses to shift between engrave and emboss appearance@property(nonatomic)     UIEdgeInsets imageEdgeInsets;        // default is UIEdgeInsetsZero

UIKIT_STATIC_INLINE UIEdgeInsets UIEdgeInsetsMake(CGFloat top, CGFloat left, CGFloat bottom, CGFloat right) {  UIEdgeInsets insets = {top, left, bottom, right};  return insets;} self.view.backgroundColor = [UIColor blackColor];  UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];//button的類型  button.frame = CGRectMake(100, 100,90, 90);//button的frame  button.backgroundColor = [UIColor cyanColor];//button的背景顏色//  [button setBackgroundImage:[UIImage imageNamed:@"man_64.png"] forState:UIControlStateNormal];//  在UIButton中有三個對EdgeInsets的設置：ContentEdgeInsets、titleEdgeInsets、imageEdgeInsets  [button setImage:[UIImage imageNamed:@"IconHome@2x.png"] forState:UIControlStateNormal];//給button添加image  button.imageEdgeInsets = UIEdgeInsetsMake(5,13,21,button.titleLabel.bounds.size.width);//設置image在button上的位置（上top，左left，下bottom，右right）這里可以寫負值，對上寫－5，那么image就象上移動5個像素  [button setTitle:@"首頁" forState:UIControlStateNormal];//設置button的title  button.titleLabel.font = [UIFont systemFontOfSize:16];//title字體大小  button.titleLabel.textAlignment = NSTextAlignmentCenter;//設置title的字體居中  [button setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];//設置title在一般情況下為白色字體  [button setTitleColor:[UIColor grayColor] forState:UIControlStateHighlighted];//設置title在button被選中情況下為灰色字體   button.titleEdgeInsets = UIEdgeInsetsMake(71, -button.titleLabel.bounds.size.width-50, 0, 0);//設置title在button上的位置（上top，左left，下bottom，右right）//  [button setContentEdgeInsets:UIEdgeInsetsMake(70, 0, 0, 0)];////  button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentCenter;//設置button的內容橫向居中。。設置content是title和image一起變化  [button addTarget:self action:@selector(tap) forControlEvents:UIControlEventTouchUpInside];  [self.view addSubview:button];//button相應的事件-(void)tap {  NSLog(@"tap a button");  UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"hello" message:@"willingseal" delegate:self cancelButtonTitle:@"ok" otherButtonTitles: nil];  [alertView show];}