Objective c UIView动画未启动？

好吧，经过长时间的搜索和故障排除，我仍然被卡住了。我正在尝试为UIView调整大小设置动画，但我无法让它在我的生活中发挥作用。我对iOS库和Objective-C都很陌生，所以这个程序可能不是最有效的。提前谢谢

ViewController.h

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController {}

-(void)animateBars;
-(void)drawBars;

@end

ViewController.m

#import "ViewController.h"
#import "Background.h"
#import <QuartzCore/QuartzCore.h>


@interface ViewController ()

@end

@implementation ViewController

-(void)animateBars
{
    CGRect newFrameGreen = CGRectMake(50.0, 0.0, 9.0, self.view.bounds.size.height);
    CGRect newFrameOrange = CGRectMake(65.0, 0.0, 9.0, self.view.bounds.size.height);
    CGRect newFrameYellow = CGRectMake(80.0, 0.0, 9.0, self.view.bounds.size.height);

    [UIView animateWithDuration: 10.0
                          delay: 0.0
                        options: UIViewAnimationOptionCurveEaseInOut
                     animations:^{
                         [self.view viewWithTag:1].frame = newFrameGreen;
                         [self.view viewWithTag:2].frame = newFrameOrange;
                         [self.view viewWithTag:3].frame = newFrameYellow;
                     }
                     completion:nil];
}


-(void)drawBars
{
    UIView *greenBar = [[UIView alloc] initWithFrame:CGRectMake(50.0, 0.0, 9.0, 1.0)];
    UIView *orangeBar = [[UIView alloc] initWithFrame:CGRectMake(65.0, 0.0, 9.0, 1.0)];
    UIView *yellowBar = [[UIView alloc] initWithFrame:CGRectMake(80.0, 0.0, 9.0, 1.0)];

    UIColor *green = [UIColor colorWithRed:142.0/255.0f green:149.0/255.0f blue:31.0/255.0f alpha:1.0f];
    UIColor *orange = [UIColor colorWithRed:204.0/255.0f green:82.0/255.0f blue:29.0/255.0f alpha:1.0f];
    UIColor *yellow = [UIColor colorWithRed:254.0/255.0f green:190.0/255.0f blue:16.0/255.0f alpha:1.0f];
    UIColor *clear = [UIColor colorWithRed:175.0/255.0f green:175.0/255.0f blue:175.0/255.0f alpha:0.0f];

    NSArray *greenColors = [NSArray arrayWithObjects:(id)clear.CGColor, green.CGColor, clear.CGColor, nil];
    NSArray *orangeColors = [NSArray arrayWithObjects:(id)clear.CGColor, orange.CGColor, clear.CGColor, nil];
    NSArray *yellowColors = [NSArray arrayWithObjects:(id)clear.CGColor, yellow.CGColor, clear.CGColor, nil];

    CAGradientLayer *greenGradient = [CAGradientLayer layer];
    CAGradientLayer *orangeGradient = [CAGradientLayer layer];
    CAGradientLayer *yellowGradient = [CAGradientLayer layer];

    greenGradient.startPoint = CGPointMake(0.0, 0.5);
    greenGradient.endPoint = CGPointMake(1.0, 0.5);

    orangeGradient.startPoint = CGPointMake(0.0, 0.5);
    orangeGradient.endPoint = CGPointMake(1.0, 0.5);

    yellowGradient.startPoint = CGPointMake(0.0, 0.5);
    yellowGradient.endPoint = CGPointMake(1.0, 0.5);

    greenGradient.colors = greenColors;
    orangeGradient.colors = orangeColors;
    yellowGradient.colors = yellowColors;

    greenGradient.frame = greenBar.bounds;
    orangeGradient.frame = orangeBar.bounds;
    yellowGradient.frame = yellowBar.bounds;

    [greenBar.layer insertSublayer:greenGradient atIndex:0];
    [orangeBar.layer insertSublayer:orangeGradient atIndex:0];
    [yellowBar.layer insertSublayer:yellowGradient atIndex:0];

    greenBar.tag = 1;
    orangeBar.tag = 2;
    yellowBar.tag = 3;

    [self.view addSubview:greenBar];
    [self.view addSubview:orangeBar];
    [self.view addSubview:yellowBar];
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    [self drawBars];
    [self animateBars];
}

-(void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    CAGradientLayer *bgLayer = [Background gradient];
    bgLayer.frame = self.view.bounds;
    [self.view.layer insertSublayer:bgLayer atIndex:0];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

---

代码工作正常，但正在为这些对象的相同位置设置动画

只需更改原始帧即可

CGRect newFrameGreen = CGRectMake(50.0, 50.0, 9.0, self.view.bounds.size.height);
CGRect newFrameOrange = CGRectMake(65.0, 50.0, 9.0, self.view.bounds.size.height);
CGRect newFrameYellow = CGRectMake(80.0, 50.0, 9.0, self.view.bounds.size.height);

---

视图框架已更改，您可以通过添加以下代码进行测试：

UIView *greenBar = [[UIView alloc] initWithFrame:CGRectMake(50.0, 0.0, 9.0, 1.0)];
UIView *orangeBar = [[UIView alloc] initWithFrame:CGRectMake(65.0, 0.0, 9.0, 1.0)];
UIView *yellowBar = [[UIView alloc] initWithFrame:CGRectMake(80.0, 0.0, 9.0, 1.0)];

//add test code
greenBar.backgroundColor = [UIColor greenColor];
orangeBar.backgroundColor = [UIColor orangeColor];
yellowBar.backgroundColor = [UIColor yellowColor];

要拉伸的高度是CALayer颜色，而不是边框：

[greenBar.layer insertSublayer:greenGradient atIndex:0];
[orangeBar.layer insertSublayer:orangeGradient atIndex:0];
[yellowBar.layer insertSublayer:yellowGradient atIndex:0];

子CALayer无法按帧自动调整大小