1.自定义tabBar
要求的tabBar和普通的tabBar有所不同,中间多了一个发布按钮,因此需要滴定仪tabBar,重写它的layoutSubViews方法,来重新布局子控件.
1.1 继承UITabBar,重写其initWithFrame方法,在方法中创建发布按钮,将其加入到tabBar中.
- (instancetype)initWithFrame:(CGRect)frame {
if ([super initWithFrame:frame]) {
//创建发布按钮
UIButton *publishBtn = [[UIButton alloc] init];
[publishBtn setImage:[UIImage imageNamed:@"tabBar_publish_icon"] forState:UIControlStateNormal];
[publishBtn setBackgroundImage:[UIImage imageNamed:@"tabBar_publish_click_icon"] forState:UIControlStateHighlighted];
[publishBtn addTarget:self action:@selector(publishClick) forControlEvents:UIControlEventTouchUpInside];
[publishBtn sizeToFit];
[self addSubview:publishBtn];
self.publishBtn = publishBtn;
}
return self;
}
1.2 重写layoutSubViews方法,遍历子控件,对子控件进行重新布局.
- (void)layoutSubviews {
[super layoutSubviews];
//获取tabBar的宽高
CGFloat w = self.frame.size.width;
CGFloat h = self.frame.size.height;
//设置发布按钮的位置
self.publishBtn.center = CGPointMake(w * 0.5, h * 0.5);
//tabBarItem的frame属性
CGFloat tabBarBtnW = w / 5;
CGFloat tabBarBtnH = h;
CGFloat tabBarBtnY = 0;
//tabBar的索引
int index = 0;
//遍历所有的子控件,找出其中的额tabBarButton,进行布局
for (UIView *tabBarBtn in self.subviews) {
NSString *className = NSStringFromClass(tabBarBtn.class);
//规避掉发布按钮
if (![className isEqualToString:@"UITabBarButton"]) continue;
CGFloat tabBarBtnX = index * tabBarBtnW;
if (index > 1) {
tabBarBtnX += tabBarBtnW;
}
tabBarBtn.frame = CGRectMake(tabBarBtnX, tabBarBtnY, tabBarBtnW, tabBarBtnH);
index++;
}
}
1.3 在tabBarController中,将自定义的tabBar替换系统的tabBar.
- (void)setupTabBar {
//tabBar属性为readonly,因此采用KVC的办法给tabBar属性赋值
[self setValue:[[LXXTabBar alloc] init] forKeyPath:@"tabBar"];
}
此时,效果如图:
Simulator Screen Shot 2017年2月25日 下午3.17.44.png
2.封装frame的修改
为了修改控件的frame更加方便,给UIView写一个分类,将frame的修改封装.
UIView+LXXExtension.h中声明属性:
@property (nonatomic, assign) CGFloat width;
@property (nonatomic, assign) CGFloat height;
@property (nonatomic, assign) CGFloat x;
@property (nonatomic, assign) CGFloat y;
@property (nonatomic, assign) CGFloat centerX;
@property (nonatomic, assign) CGFloat centerY;
UIView+LXXExtension.m中实现相应的封装方法:
- (void)setWidth:(CGFloat)width
{
CGRect frame = self.frame;
frame.size.width = width;
self.frame = frame;
}
- (CGFloat)width
{
return self.frame.size.width;
}
此时设置frame的代码为:
封装前:
CGFloat w = self.frame.size.width;
CGFloat h = self.frame.size.height;
封装后:
CGFloat w = self.width;
CGFloat h = self.height;
3.设置导航栏
3.1 在tabBarController中,将每个子控制器包装一个导航控制器.
/**
设置tabBar
*/
- (void)setupOneChildVc:(UIViewController *)vc title:(NSString *)title image:(NSString *)image selectedImage:(NSString *)selectedImage
{
vc.title = title;
vc.tabBarItem.image = [UIImage imageNamed:image];
vc.tabBarItem.selectedImage = [UIImage imageNamed:selectedImage];
UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:vc];
[self addChildViewController:nav];
}
Simulator Screen Shot 2017年2月25日 下午3.53.37.png
3.2 封装导航栏上UIBarButtonItem的创建方法
给UIBarButtonItem创建了一个分类:
/**
创建UIBarButtonItem
@param image 图片
@param highImage 高亮图片
@param target 方法的执行者
@param action 方法
@return 创建好的UIBarButtonItem
*/
+ (instancetype)itemWithImage:(NSString *)image highImage:(NSString *)highImage target:(id)target action:(SEL)action
{
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button setImage:[UIImage imageNamed:image] forState:UIControlStateNormal];
[button setImage:[UIImage imageNamed:highImage] forState:UIControlStateHighlighted];
[button sizeToFit];
[button addTarget:target action:action forControlEvents:UIControlEventTouchUpInside];
return [[UIBarButtonItem alloc] initWithCustomView:button];
}
再创建item时,只需要一行代码:
//设置左上角
self.navigationItem.leftBarButtonItem = [UIBarButtonItem itemWithImage:@"MainTagSubIcon" highImage:@"MainTagSubIconClick" target:self action:@selector(mainTagSubClick)];
Simulator Screen Shot 2017年2月25日 下午4.14.11.png
4.调整项目文件结构
项目整体采用MVP模式,文件结构如下:
5.自定义导航控制器
当push到一个新的控制器时,新的控制器的左上角显示的为上一个控制器导航栏的title.为了使push到的新的控制器的左上角统一显示为"返回",需要拦截导航控制器的push的过程,即需要自定义导航控制器,重写push这个方法.
- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated
{
//如果push进来的不是第一个控制器
if (self.childViewControllers.count > 0) {
// 当push这个子控制器时, 隐藏底部的工具条
viewController.hidesBottomBarWhenPushed = YES;
UIButton *backBtn = [UIButton buttonWithType:UIButtonTypeCustom];
[backBtn setImage:[UIImage imageNamed:@"navigationButtonReturn"] forState:UIControlStateNormal];
[backBtn setImage:[UIImage imageNamed:@"navigationButtonReturnClick"] forState:UIControlStateHighlighted];
[backBtn setTitle:@"返回" forState:UIControlStateNormal];
[backBtn setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
[backBtn setTitleColor:[UIColor redColor] forState:UIControlStateHighlighted];
backBtn.titleLabel.font = [UIFont systemFontOfSize:14];
[backBtn sizeToFit];
[backBtn addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside];
//设置按钮的内边距,可以让按钮更靠近左边
backBtn.contentEdgeInsets = UIEdgeInsetsMake(0, -20, 0, 0);
viewController.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:backBtn];
}
//放在后面,是想先帮你设置导航栏的左边再进行push,push成功之后如果想要重新设置左边,可以覆盖
[super pushViewController:viewController animated:animated];
}
- (void)back
{
[self popViewControllerAnimated:YES];
}