----------UI窗口于视图的创建示例----------
在window上创建赤橙黄绿青蓝紫七个视图，互相嵌套，设置定时器，每秒每个视图随机变换颜色，并且旋转，十秒后停止，视图全部移除。
---AppDelegate.h中声明视图和一个计时的变量
@interface AppDelegate : UIResponder <UIApplicationDelegate>
{
UIView *view1;
UIView *view2;
UIView *view3;
UIView *view4;
UIView *view5;
UIView *view6;
UIView *view7;
int second;
}
---AppDelegate.m中实现题中要求
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
CGRect rect = [UIScreen mainScreen].bounds;
//创建主Window
self.window = [[UIWindow alloc]initWithFrame:rect];
self.window.backgroundColor = [UIColor blackColor];
[self.window makeKeyAndVisible];
//创建View
view1 = [[UIView alloc]initWithFrame:CGRectMake(70, 70, 250, 250)];
view1.backgroundColor= [UIColor redColor];
view1.tag = 1;
view2 = [[UIView alloc]initWithFrame:CGRectMake(15, 15, 220, 220)];
view2.backgroundColor= [UIColor orangeColor];
view3 = [[UIView alloc]initWithFrame:CGRectMake(15, 15, 190, 190)];
view3.backgroundColor= [UIColor yellowColor];
view4 = [[UIView alloc]initWithFrame:CGRectMake(15, 15, 160, 160)];
view4.backgroundColor= [UIColor greenColor];
view5 = [[UIView alloc]initWithFrame:CGRectMake(15, 15 , 130, 130)];
view5.backgroundColor= [UIColor cyanColor];
view6 = [[UIView alloc]initWithFrame:CGRectMake(15, 15, 100, 100)];
view6.backgroundColor= [UIColor blueColor];
view7 = [[UIView alloc]initWithFrame:CGRectMake(25, 25, 50, 50)];
view7.backgroundColor= [UIColor purpleColor];
[self.window addSubview:view1];
[view1 addSubview:view2];
[view2 addSubview:view3];
[view3 addSubview:view4];
[view4 addSubview:view5];
[view5 addSubview:view6];
[view6 addSubview:view7];
second = 10;
//定时器
[NSTimer scheduledTimerWithTimeInterval:1
target:self
selector:@selector(timeAction:)
userInfo:nil
repeats:YES];
return YES;
}
- (void)timeAction:(NSTimer *)timer{
//七个视图颜色随机变
view1.backgroundColor = [UIColor colorWithRed🙁arc4random()%255/255.0) green🙁arc4random()%255/255.0) blue🙁arc4random()%255/255.0) alpha:1];
view2.backgroundColor = [UIColor colorWithRed🙁arc4random()%255/255.0) green🙁arc4random()%255/255.0) blue🙁arc4random()%255/255.0) alpha:1];
view3.backgroundColor = [UIColor colorWithRed🙁arc4random()%255/255.0) green🙁arc4random()%255/255.0) blue🙁arc4random()%255/255.0) alpha:1];
view4.backgroundColor = [UIColor colorWithRed🙁arc4random()%255/255.0) green🙁arc4random()%255/255.0) blue🙁arc4random()%255/255.0) alpha:1];
view5.backgroundColor = [UIColor colorWithRed🙁arc4random()%255/255.0) green🙁arc4random()%255/255.0) blue🙁arc4random()%255/255.0) alpha:1];
view6.backgroundColor = [UIColor colorWithRed🙁arc4random()%255/255.0) green🙁arc4random()%255/255.0) blue🙁arc4random()%255/255.0) alpha:1];
view7.backgroundColor = [UIColor colorWithRed🙁arc4random()%255/255.0) green🙁arc4random()%255/255.0) blue🙁arc4random()%255/255.0) alpha:1];
//旋转
UIView *view = [self.window viewWithTag:1];
CGAffineTransform trans = view.transform;
view.transform = CGAffineTransformRotate(trans, M_PI/10);
//十秒后计时器停止，视图移除
second--;
if (second < 0) {
[timer invalidate];
[view1 removeFromSuperview];
return;
}
}
