波浪线图等同于折线图, 只是添加了填充, 另外实现波浪的效果.
实现同样自定义封装了view, 在UIBezierPath的分类中实现波浪的效果:

// .h
#import <UIKit/UIKit.h>

@interface LineChartView : UIView

@property (nonatomic, strong) NSArray *titleForYArr;

@property (nonatomic, strong) NSArray *titleForXArr;

@property (nonatomic, strong) NSArray *valueArr;

@property (nonatomic, strong) UIColor *lineColor;

- (instancetype)initWithFrame:(CGRect)frame;

- (void)startDraw;

@end
// .m
#import "LineChartView.h"
#import "UIBezierPath+category.h"

@interface LineChartView()<CAAnimationDelegate>

@property (nonatomic, strong) CAShapeLayer *lineChartLayer;

@end

@implementation LineChartView {
    CGFloat width;
    CGFloat height;
}

static CGFloat edgeLeft = 30;
static CGFloat edgeRight = 20;

static CGFloat edgeUp = 50;
static CGFloat edgeDown = 30;

- (instancetype)initWithFrame:(CGRect)frame {
    if (self = [super initWithFrame:frame]) {
        
        self.backgroundColor = [UIColor lightGrayColor];
        
        width = frame.size.width - edgeLeft - edgeRight;
        height = frame.size.height - edgeUp - edgeDown;
    }
    return self;
}
// 画出坐标轴
- (void)drawRect:(CGRect)rect {
    
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetLineWidth(context, 1.0);
    CGContextSetRGBStrokeColor(context, 0.6, 0.6, 0.6, 1);
    CGContextMoveToPoint(context, edgeLeft, edgeUp);
    CGContextAddLineToPoint(context, edgeLeft, edgeUp + height);
    CGContextAddLineToPoint(context,edgeLeft + width, edgeUp + height);
    CGContextStrokePath(context);
}


#pragma mark 画折线图
- (void)dravLine{

    NSInteger yearNum = self.titleForXArr.count;
    if (yearNum <= 0) {
        return;
    }
    CGFloat widthForX = width / yearNum;
    CGFloat maxValue = [[self.titleForYArr lastObject] floatValue];
    
    if (maxValue <= 0) {
        return;
    }
    
    UIBezierPath *pathLine = [[UIBezierPath alloc] init];
    [pathLine moveToPoint:CGPointMake(edgeLeft + widthForX * 0.5, ((maxValue - [self.valueArr[0] floatValue]) / maxValue) * height + edgeUp)];
    
    // 创建折线点标记
    for (NSInteger i = 1; i < self.valueArr.count; i++) {
        
        CGPoint pointCenter = CGPointMake(edgeLeft + widthForX * (i + 0.5), (maxValue - [self.valueArr[i] floatValue]) / maxValue * height + edgeUp);
        
        [pathLine addLineToPoint:pointCenter];
    }
    // 实现波浪线
    pathLine = [pathLine smoothedPathWithGranularity:20];
    
    [pathLine addLineToPoint:CGPointMake(edgeLeft + width - widthForX * 0.5, height + edgeUp)];
    [pathLine addLineToPoint:CGPointMake(edgeLeft + widthForX * 0.5, height + edgeUp)];
    
    CAShapeLayer  *lineChartLayer = [CAShapeLayer layer];
    lineChartLayer.path = pathLine.CGPath;
    lineChartLayer.strokeColor = _lineColor.CGColor;
    lineChartLayer.fillColor = [[UIColor greenColor] CGColor];
    lineChartLayer.lineWidth = 0.0;
    lineChartLayer.lineCap = kCALineCapRound;
    lineChartLayer.lineJoin = kCALineJoinBevel;
    lineChartLayer.lineDashPhase = 5.0;
    lineChartLayer.miterLimit = 10.0;
    
    [self.layer addSublayer:lineChartLayer];
}

#pragma mark 创建x轴的数据
- (void)setTitleForXArr:(NSArray *)titleForXArr {
    _titleForXArr = titleForXArr;
    [self createLabelX];
}
- (void)createLabelX{

    NSInteger yearNum = self.titleForXArr.count;
    if (yearNum <= 0) {
        return;
    }
    CGFloat widthForX = width / yearNum;
    
    for (NSInteger i = 0; i < yearNum; i++) {
        
        UILabel *labelYear = [[UILabel alloc] initWithFrame:CGRectMake(edgeLeft + widthForX * i, height + edgeUp, widthForX, edgeDown)];
        labelYear.tag = 1000 + i;
        labelYear.text = self.titleForXArr[i];
        labelYear.font = [UIFont systemFontOfSize:14];
        labelYear.textAlignment = NSTextAlignmentCenter;
        [self addSubview:labelYear];
    }
}
#pragma mark 创建y轴数据及虚线
- (void)setTitleForYArr:(NSArray *)titleForYArr {
    _titleForYArr = titleForYArr;
    [self createLabelY];
    [self setLineDash];
}
- (void)createLabelY{

    NSInteger numForY = _titleForYArr.count;
    if (numForY <= 1) {
        return;
    }
    CGFloat widthForY = edgeLeft;
    CGFloat heightForY = height / (numForY - 1);
    
    for (NSInteger i = 0; i < numForY; i++) {
        
        UILabel *labelForY = [[UILabel alloc] initWithFrame:CGRectMake(0, edgeUp + (i - 0.5) * heightForY, widthForY, heightForY)];
        
        labelForY.tag = 2000 + i;
        labelForY.text = _titleForYArr[numForY - i - 1];
        labelForY.font = [UIFont systemFontOfSize:12];
        labelForY.textAlignment = NSTextAlignmentCenter;
        [self addSubview:labelForY];
    }
}
#pragma mark - 添加虚线
- (void)setLineDash {
    
    NSInteger numForY = _titleForYArr.count - 1;
    if (numForY <= 0) {
        return;
    }
    CGFloat heightForY = height / numForY;
    
    for (NSInteger i = 0; i < numForY; i++) {
        
        CAShapeLayer *dashLayer = [CAShapeLayer layer];
        dashLayer.strokeColor = [UIColor colorWithRed:0.6 green:0.6 blue:0.6 alpha:1].CGColor;
        dashLayer.lineWidth = 1.0;
        
        UIBezierPath *path = [[UIBezierPath alloc] init];
        path.lineWidth = 1.0;
        
        [path moveToPoint:CGPointMake(edgeLeft, edgeUp + i * heightForY)];
        [path addLineToPoint:CGPointMake(edgeLeft + width, edgeUp + i * heightForY)];
        CGFloat dash[] = {10,10};
        [path setLineDash:dash count:2 phase:10];
        [path stroke];
        dashLayer.path = path.CGPath;
        [self.layer addSublayer:dashLayer];
    }
}
#pragma mark - 开始画折线
- (void)startDraw {
    [self dravLine];
}

@end
// 分类.h
#import <UIKit/UIKit.h>

@interface UIBezierPath (category)

- (UIBezierPath *)smoothedPathWithGranularity:(NSInteger)granularity;

@end
// 分类.m
#import "UIBezierPath+category.h"

@implementation UIBezierPath (category)

void getPointsFromBezier(void * info, const CGPathElement * element){
    NSMutableArray *bezierPoints = (__bridge NSMutableArray *)info;
    CGPathElementType type = element->type;
    CGPoint * points = element->points;
    
    if (type != kCGPathElementCloseSubpath) {
        [bezierPoints addObject:[NSValue valueWithCGPoint:points[0]]];
        if ((type != kCGPathElementAddLineToPoint) && (type != kCGPathElementMoveToPoint)) {
            [bezierPoints addObject:[NSValue valueWithCGPoint:points[1]]];
        }
    }
    if (type == kCGPathElementAddCurveToPoint) {
        [bezierPoints addObject:[NSValue valueWithCGPoint:points[2]]];
    }
}

- (NSMutableArray *)pointsFromBezierPath:(UIBezierPath *)bezierPath{
    NSMutableArray * points = [NSMutableArray array];
    CGPathApply(bezierPath.CGPath, (__bridge void *)points, getPointsFromBezier);
    return points;
}

- (UIBezierPath *)smoothedPathWithGranularity:(NSInteger)granularity{
    NSMutableArray * points = [NSMutableArray arrayWithArray:[self pointsFromBezierPath:self]];

    if (points.count < 4) {
        return [self copy];
    }
    
    [points insertObject:[points objectAtIndex:0] atIndex:0];
    [points addObject:[points lastObject]];
    
    UIBezierPath * smoothedPath = [self copy];
    [smoothedPath removeAllPoints];
    [smoothedPath moveToPoint:[(NSValue *)[points objectAtIndex:0] CGPointValue]];
    
    for (NSUInteger i = 1; i < points.count - 2; i++) {
        CGPoint p0 = [(NSValue *)[points objectAtIndex:i-1] CGPointValue];
        CGPoint p1 = [(NSValue *)[points objectAtIndex:i] CGPointValue];
        CGPoint p2 = [(NSValue *)[points objectAtIndex:i+1] CGPointValue];
        CGPoint p3 = [(NSValue *)[points objectAtIndex:i+2] CGPointValue];
        
        for (int i = 1; i < granularity; i++)
        {
            float t = (float) i * (1.0f / (float) granularity);
            float tt = t * t;
            float ttt = tt * t;
            
            CGPoint pi;
            pi.x = 0.5 * (2*p1.x+(p2.x-p0.x)*t + (2*p0.x-5*p1.x+4*p2.x-p3.x)*tt + (3*p1.x-p0.x-3*p2.x+p3.x)*ttt);
            pi.y = 0.5 * (2*p1.y+(p2.y-p0.y)*t + (2*p0.y-5*p1.y+4*p2.y-p3.y)*tt + (3*p1.y-p0.y-3*p2.y+p3.y)*ttt);
            [smoothedPath addLineToPoint:pi];
        }
        
        [smoothedPath addLineToPoint:p2];
    }
    
    [smoothedPath addLineToPoint:[(NSValue *)[points objectAtIndex:points.count - 1] CGPointValue]];
    return smoothedPath;
}

@end

// 使用
- (void)viewDidLoad {
    [super viewDidLoad];
    
    LineChartView *lineView = [[LineChartView alloc] initWithFrame:CGRectMake(0, 100, self.view.bounds.size.width, 190)];
    lineView.titleForYArr = @[@"0",@"1",@"2",@"3",@"4",@"5"];
    lineView.titleForXArr = @[@"2013年",@"2014年",@"2015年",@"2016年",@"2017年"];
    lineView.valueArr = @[@"0.8",@"1.9",@"4.0",@"1.3",@"2.5"];
    
    lineView.lineColor = [UIColor redColor];
    [self.view addSubview:lineView];
    
    [lineView startDraw];
}