这对我来说对 leftBarButtonItem 有用:如果您希望 UIBarButtonItem 精确显示在位置 (0, 0),您可以创建一个 UIButton,将其框架设置为 (-5, 0, width, height),假设偏移量为左 barbutton 项目是 (5, 0),并将其放置在您设置为 leftBarButtonItem 的 UIView 中。
#import "UINavigationItem+CSAButtons.h"
@implementation UINavigationItem (CSAButtons)
- (void) makeLeftBarButtonWithTarget:(id)target action:(SEL)action {
UIImage * imageNormal = [UIImage imageNamed:@"normal.png"];
UIImage * imageHighlighted = [UIImage imageNamed:@"highlighted.png"];
UIImage * imageDisabled = [UIImage imageNamed:@"disabled.png"];
// create your button
UIButton * button = [UIButton buttonWithType:UIButtonTypeCustom];
button.exclusiveTouch = YES;
[button addTarget:target action:action forControlEvents:UIControlEventTouchUpInside];
[button setBackgroundImage:imageNormal forState:UIControlStateNormal];
[button setBackgroundImage:imageHighlighted forState:UIControlStateHighlighted];
[button setBackgroundImage:imageDisabled forState:UIControlStateDisabled];
// set the frame of the button (better to grab actual offset of leftbarbuttonitem instead of magic numbers)
button.frame = CGRectMake(-5.0, 0.0, imageNormal.size.width, imageNormal.size.height);
UIView * view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, imageNormal.size.width, imageNormal.size.height)];
[view addSubview:button];
// set the barbuttonitem to be the view
UIBarButtonItem * barButtonItem = [[UIBarButtonItem alloc] initWithCustomView:view];
self.leftBarButtonItem = barButtonItem;
}