开发笔记 视图管理 子视图切图和查询子视图

我在开发一个项目的时候！在一个视图要有两个子视图来回切换！我用 setHidden 设置bool 值 隐藏和显示。看书的时候，发现iosSDK已经给了相应的函数

 //交换俩个视图

  [self.view exchangeSubviewAtIndex:<#(NSInteger)#> withSubviewAtIndex:<#(NSInteger)#>];

 

 然后通过

[self.view bringSubviewToFront:viewtwo]; //将子视图提前

[self.viewsendSubviewToBack:viewone]; //将子视图提后

下面写了个demo 验证下

我在父类视图上加了两个子视图分别为viewone和viewtwo 通过分度控件来回切换

- (void)viewDidLoad

{

    [superviewDidLoad];

    

    viewone = [[UIViewalloc]initWithFrame:CGRectMake(0,100,self.view.bounds.size.width,self.view.bounds.size.height)];

    

    viewone.backgroundColor = [UIColorgreenColor];

    

    UILabel *label1 = [[UILabelalloc]initWithFrame:CGRectMake(100,100,100, 40)];

    

    

    label1.text =@"hello";

    

    [label1 setBackgroundColor:[UIColorclearColor]];

    

    [viewone addSubview:label1];

    

    viewone.tag =101;

    [self.viewaddSubview:viewone];

    

    viewtwo = [[UIViewalloc]initWithFrame:CGRectMake(0,100, self.view.bounds.size.width,self.view.bounds.size.height)];

    viewtwo.backgroundColor = [UIColorgrayColor];

    viewtwo.tag =102;

       [self.viewaddSubview:viewtwo];

    

    //交换俩个视图

    [self.viewexchangeSubviewAtIndex:101withSubviewAtIndex:102];

}

//在故事板中拖拽了一个分段控件

- (IBAction)ChangView:(id)sender

{

    UISegmentedControl *segmengt = (UISegmentedControl *)sender;

    

    if (segmengt.selectedSegmentIndex ==0)

    {

      

        

        [self.viewbringSubviewToFront:viewtwo];

        //[self.view sendSubviewToBack:viewone];

        

        

    }

    else

    {

      

        [self.viewbringSubviewToFront:viewone];

        

    }

    

     

}

这样就可以来回切换了！

在项目中有些数据的变更要要通知父类视图！我是通过发送通知，但是也可以通过父类视图查询子视图

// Return an exhaustive descent of the view's subviews

NSArray *allSubviews(UIView *aView)

{

NSArray *results = [aViewsubviews];

for (UIView *eachViewin [aView subviews])

{

NSArray *riz =allSubviews(eachView);

if (riz) results = [resultsarrayByAddingObjectsFromArray:riz];

}

return results;

}

// Return all views throughout the application

NSArray *allApplicationViews()

{

    NSArray *results = [[UIApplicationsharedApplication] windows];

    for (UIWindow *windowin [[UIApplicationsharedApplication] windows])

{

NSArray *riz =allSubviews(window);

        if (riz) results = [resultsarrayByAddingObjectsFromArray: riz];

}

    return results;

}

// Return an array of parent views from the window down to the view

NSArray *pathToView(UIView *aView)

{

    NSMutableArray *array = [NSMutableArrayarrayWithObject:aView];

    UIView *view = aView;

    UIWindow *window = aView.window;

    while (view != window)

    {

        view = [view superview];

        [array insertObject:viewatIndex:0];

    }

    return array;

}

- (void) collectViews: (id) sender

{

    

printf("Subviews of the main view:\n");

    //任何视图的子视图

CFShow((__bridgeCFTypeRef)(allSubviews(self.view)));

printf("Path to each main subview:\n");

    //每个视图的集合可以观察一个特定的label 上的值或者滑块按钮等

for (UIView *eachViewin allSubviews(self.view))

CFShow((__bridgeCFTypeRef)(pathToView(eachView)));

// More views than you could dream of!

printf("\nAll window subviews:\n");

    //每一个窗口

    CFShow((__bridgeCFTypeRef)(allApplicationViews()));

}

 

Demo http://download.youkuaiyun.com/detail/lengshengren/6574425

 额外ios sdk 还提供了其他的管理视图的函数

//删除子视图

- (void)removeFromSuperview; 

//插入视图

- (void)insertSubview:(UIView *)view atIndex:(NSInteger)index;  

- (void)insertSubview:(UIView *)view belowSubview:(UIView *)siblingSubview;

- (void)insertSubview:(UIView *)view aboveSubview:(UIView *)siblingSubview;

//两个视图交换

- (void)exchangeSubviewAtIndex:(NSInteger)index1 withSubviewAtIndex:(NSInteger)index2;

//添加视图

- (void)addSubview:(UIView *)view;

//提前和置后

- (void)bringSubviewToFront:(UIView *)view;

- (void)sendSubviewToBack:(UIView *)view;

//调用addSubview 成功后给该视图发送didAddSubview 回调 触发uiview 的子类新

增视图时执行其他操作

- (void)didAddSubview:(UIView *)subview;

//回调通知父视图 子视图即将被删除

- (void)willRemoveSubview:(UIView *)subview;

//通知相关视图他们的上级视图有所变化。这些视图也可能需要以上某种方式对新的父类视图做出响应

如何视图从父视图下删除则改视图的新父视图就是为nil

- (void)didMoveToSuperview;

// 移动前发生通知
- (void)willMoveToSuperview:(UIView *)newSuperview;

移动到window层次 回调

- (void)willMoveToWindow:(UIWindow *)newWindow;

- (void)didMoveToWindow;