//
// ViewController.m
// test_CAGradientLayer
//
// Created by admin on 3/4/16.
// Copyright © 2016 jeffasd. All rights reserved.
//
#import "ViewController.h"
#import "GardView.h"
@interface ViewController ()
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
GardView *view = [[GardView alloc] initWithFrame:CGRectMake(100, 300, 500, 50)];
// view.frame = CGRectMake(100, 30, 50, 50);
[self.view addSubview:view];
[view setProgress:0.6];
[view performAnimation];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end
//
// GardView.h
// test_CAGradientLayer
//
// Created by admin on 3/4/16.
// Copyright © 2016 jeffasd. All rights reserved.
//
#import <UIKit/UIKit.h>
@interface GardView : UIView
- (void)setProgress:(CGFloat)value;
- (void)performAnimation;
@end//
// GardView.m
// test_CAGradientLayer
//
// Created by admin on 3/4/16.
// Copyright © 2016 jeffasd. All rights reserved.
//
#import "GardView.h"
@interface GardView()
@property (nonatomic, strong) CALayer *maskLayer;
@property (nonatomic, assign) CGFloat progress;
@end
@implementation GardView
+ (Class)layerClass {
return [CAGradientLayer class];
}
Use a horizontal gradient
//CAGradientLayer *layer = (id)[self layer];
//[layer setStartPoint:CGPointMake(0.0, 0.5)];
//[layer setEndPoint:CGPointMake(1.0, 0.5)];
//
Create colors using hues in +5 increments
//NSMutableArray *colors = [NSMutableArray array];
//for (NSInteger hue = 0; hue <= 360; hue += 5) {
//
// UIColor *color;
// color = [UIColor colorWithHue:1.0 * hue / 360.0
// saturation:1.0
// brightness:1.0
// alpha:1.0];
// [colors addObject:(id)[color CGColor]];
//}
//
//[layer setColors:[NSArray arrayWithArray:colors]];
- (instancetype)initWithFrame:(CGRect)frame{
self = [super initWithFrame:frame];
if (self != nil) {
_maskLayer = [CALayer layer];
[_maskLayer setFrame:CGRectMake(0, 0, 0, frame.size.height)];
[_maskLayer setBackgroundColor:[[UIColor blackColor] CGColor]];
[self.layer setMask:_maskLayer];
// Use a horizontal gradient
CAGradientLayer *layer = (id)[self layer];
[layer setStartPoint:CGPointMake(0.0, 0.5)];
[layer setEndPoint:CGPointMake(1.0, 0.5)];
// Create colors using hues in +5 increments
NSMutableArray *colors = [NSMutableArray array];
for (NSInteger hue = 0; hue <= 360; hue += 5) {
UIColor *color;
color = [UIColor colorWithHue:1.0 * hue / 360.0
saturation:1.0
brightness:1.0
alpha:1.0];
[colors addObject:(id)[color CGColor]];
}
[layer setColors:[NSArray arrayWithArray:colors]];
}
return self;
}
- (void)performAnimation {
// Move the last color in the array to the front
// shifting all the other colors.
CAGradientLayer *layer = (id)[self layer];
NSMutableArray *mutable = [[layer colors] mutableCopy];
id lastColor = [mutable lastObject] ;
[mutable removeLastObject];
[mutable insertObject:lastColor atIndex:0];
NSArray *shiftedColors = [NSArray arrayWithArray:mutable];
// Update the colors on the model layer
[layer setColors:shiftedColors];
// Create an animation to slowly move the gradient left to right.
CABasicAnimation *animation;
animation = [CABasicAnimation animationWithKeyPath:@"colors"];
[animation setToValue:shiftedColors];
[animation setDuration:0.08];
[animation setRemovedOnCompletion:YES];
[animation setFillMode:kCAFillModeForwards];
[animation setDelegate:self];
[layer addAnimation:animation forKey:@"animateGradient"];
}
- (void)animationDidStop:(CAAnimation *)animation finished:(BOOL)flag {
[self performAnimation];
}
- (void)setProgress:(CGFloat)value {
if (_progress != value) {
// Progress values go from 0.0 to 1.0
_progress = MIN(1.0, fabs(value));
[self setNeedsLayout];
}
}
- (void)layoutSubviews {
// Resize our mask layer based on the current progress
CGRect maskRect = [_maskLayer frame];
maskRect.size.width = CGRectGetWidth([self bounds]) * _progress;
[_maskLayer setFrame:maskRect];
}
@end
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