用CALayer实现下载进度条控件

用CALayer实现下载进度条

效果：

源码：

//
//  ViewController.m
//  ProgressView
//
//  Created by YouXianMing on 14/11/18.
//  Copyright (c) 2014年 YouXianMing. All rights reserved.
//
 
#import "ViewController.h"
 
@interface ViewController ()
 
@property (nonatomic, strong) NSTimer *timer;
@property (nonatomic, strong) CALayer *layer;
 
@end
 
@implementation ViewController
 
- (void)viewDidLoad {
    [super viewDidLoad];
 
    self.view.backgroundColor = [UIColor blackColor];
 
    // CALayer
    _layer                 = [CALayer layer];
    _layer.frame           = CGRectMake(, , , );
    _layer.backgroundColor = [UIColor redColor].CGColor;
    [self.view.layer addSublayer:_layer];
 
    // 定时器
    _timer = [NSTimer scheduledTimerWithTimeInterval:.f
                                              target:self
                                            selector:@selector(timerEvent)
                                            userInfo:nil
                                             repeats:YES];
}
 
/**
 *  定时器
 */
- (void)timerEvent {
    // 显式动画
    _layer.frame = CGRectMake(, , arc4random()%, );
}
 
@end

封装后的源码：

//
//  ProgressView.h
//  ProgressView
//
//  Created by YouXianMing on 14/11/18.
//  Copyright (c) 2014年 YouXianMing. All rights reserved.
//
 
#import <UIKit/UIKit.h>
 
@interface ProgressView : UIView
 
@property (nonatomic, strong) UIColor *progressColor;
@property (nonatomic, assign) CGFloat  progress;
 
@end

//
//  ProgressView.m
//  ProgressView
//
//  Created by YouXianMing on 14/11/18.
//  Copyright (c) 2014年 YouXianMing. All rights reserved.
//
 
#import "ProgressView.h"
 
@interface ProgressView ()
 
{
    CALayer   *_backLayer;
    CGFloat    _frameWidth;
    CGFloat    _layerWidth;
}
 
@end
 
@implementation ProgressView
 
- (instancetype)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        _backLayer       = [CALayer layer];
 
        _frameWidth      = self.bounds.size.width;
        _layerWidth      = ;
 
        _backLayer.frame = CGRectMake(, , _layerWidth, frame.size.height);
        [self.layer addSublayer:_backLayer];
    }
    return self;
}
 
@synthesize progressColor = _progressColor;
- (void)setProgressColor:(UIColor *)progressColor {
    _progressColor             = progressColor;
    _backLayer.backgroundColor = _progressColor.CGColor;
}
- (UIColor *)progressColor {
    return _progressColor;
}
 
@synthesize progress = _progress;
- (void)setProgress:(CGFloat)progress {
    _progress = progress;
 
    CGRect rect = _backLayer.frame;
    if (_progress <= ) {
        rect.size.width = ;
    } else if (_progress >= ) {
        rect.size.width = _frameWidth;
    } else {
        rect.size.width = _progress * _frameWidth;
    }
 
    _backLayer.frame = rect;
}
- (CGFloat)progress {
    return _progress;
}
 
@end