今天mark一下navgationbar的知识，有时候我们项目需要做像网易云音乐那样的navgationbar，有多个item同在右边或者左边玩耍。
见效果图，这个是我们要实现的。
navgationbar.png
为了帮助大家学习，我先说下曲线救国的两种方法。也是我爬过的坑。共勉。
- 我尝试了三种方法，一种是用toolbar放在navgationBar.rightBarButtonItem上
- (void)initNav{
/* CREATE BOOKMARKS BUTTON */
UIButton *bookmarksButton = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, kBookmarksImage.size.width, kBookmarksImage.size.height)];
bookmarksButton.backgroundColor = [UIColor greenColor];
[bookmarksButton setImage:kBookmarksImage forState:UIControlStateNormal];
[bookmarksButton addTarget:self action:@selector(toolbarButtonTapped:) forControlEvents:UIControlEventTouchDown];
bookmarksButton.tag = 1;
UIBarButtonItem *bookmarksButtonItem = [[UIBarButtonItem alloc] initWithCustomView:bookmarksButton];
UIBarButtonItem *spacer = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
spacer.width = SPACE_BETWEEN_BUTTONS;
UIButton *bookmarksButton2 = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, kBookmarksImage.size.width, kBookmarksImage.size.height)];
bookmarksButton2.backgroundColor = [UIColor orangeColor];
[bookmarksButton2 setImage:kBookmarksImage forState:UIControlStateNormal];
[bookmarksButton2 addTarget:self action:@selector(toolbarButtonTapped:) forControlEvents:UIControlEventTouchDown];
bookmarksButton2.tag = 2;
UIBarButtonItem *bookmarksButtonItem2 = [[UIBarButtonItem alloc] initWithCustomView:bookmarksButton2];
NSMutableArray<UIBarButtonItem*>*buttons = [NSMutableArray array];
[buttons addObjectsFromArray:@[bookmarksButtonItem,spacer,bookmarksButtonItem2]];
/* ADD ALL THESE BUTTONS TO CUSTOM TOOLBAR AND TOOLBAR TO NAVIGATION BAR */
UIToolbar *customToolbar = [[UIToolbar alloc]
initWithFrame:CGRectMake(0.0f, 0.0f, 50, 44.01f)]; // 44.01 shifts it up 1px for some reason
customToolbar.backgroundColor = [UIColor redColor];
customToolbar.clearsContextBeforeDrawing = NO;
customToolbar.clipsToBounds = NO;
customToolbar.tintColor = [UIColor colorWithWhite:0.305f alpha:0.0f]; // closest I could get by eye to black, translucent style.
customToolbar.barStyle = -1; // clear background
[customToolbar setItems: buttons animated:NO];
UIBarButtonItem *customUIBarButtonitem = [[UIBarButtonItem alloc] initWithCustomView:customToolbar];
self.navigationItem.rightBarButtonItem = customUIBarButtonitem;
}
效果是这样的
error.png
紫色区和黄色区是我们无法改变的，我当时以为这是最接近神的操作了，然而失败了。
- 还有一种是用自定义view实现，效果虽然如出一辙，贼繁琐，需要重写btn还需要将view加载到navgationbar上面，因为原始的navgationbar的背景色是渐变色，那么此时问题来了，我右滑返回上级viewcontroller，自定义view并未消失而，你需要让它消失你要做很多脏活。不痛快
重头戏来了，原谅我说了那么多废话
上代码
- (void)initNavBar{
// 需要注意为什么两个btn point都是（0，0）因为设置frame只能控制按钮的大小
UIButton *searchBtn = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 22, 22)];
[searchBtn setImage:[UIImage imageNamed:@"spotsupervision_playback_searchbtn"] forState:UIControlStateNormal];
[searchBtn addTarget:self action:@selector(toolbarButtonTapped:) forControlEvents:UIControlEventTouchDown];
searchBtn.tag = 1;
UIButton *uploadBtn = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 22, 22)];
[uploadBtn setImage:[UIImage imageNamed:@"spotsupervision_playback_uploadbtn"] forState:UIControlStateNormal];
[uploadBtn addTarget:self action:@selector(toolbarButtonTapped:) forControlEvents:UIControlEventTouchDown];
uploadBtn.tag = 2;
UIBarButtonItem *btn_search = [[UIBarButtonItem alloc] initWithCustomView:searchBtn];
UIBarButtonItem *btn_upload = [[UIBarButtonItem alloc] initWithCustomView:uploadBtn];
UIBarButtonItem *negativeRightSpacer = [[UIBarButtonItem alloc]
initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace
target:nil action:nil];
/**
* width为负数时，相当于btn向右移动width数值个像素，由于按钮本身和边界间距为5pix，所以width设为-5时，间距正好调整
* 为0；width为正数时，正好相反，相当于往左移动width数值个像素
*/
negativeRightSpacer.width = -5;
UIBarButtonItem *negativeMidSpacer = [[UIBarButtonItem alloc]
initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace
target:nil action:nil];
negativeMidSpacer.width = 10;
self.navigationItem.rightBarButtonItems = [NSArray arrayWithObjects:negativeRightSpacer, btn_upload, negativeMidSpacer, btn_search, nil];
}
不解释一切尽在代码中。
