iOS 图表工具charts之CandleStickChartView(K线)
关于charts的系列视图介绍传送门：
iOS 图表工具charts介绍
iOS 图表工具charts之LineChartView
iOS 图表工具charts之BarChartView
iOS 图表工具charts之PieChartView
iOS 图表工具charts之CandleStickChartView
iOS 图表工具charts之CombinedChartView
CandleStickChartView在charts中可以用来绘制K线图,由于charts是基于swift开发的，如果需要和objective-C混编(通过pod的方式不用管)，可以参考我的上几篇文章iOS OC中桥接swift第三方库》，这里主要讲的是CandleStickChartView的一些常用属性和一些基本用法，实际情况以开发为准
CandleStickChartView的基本属性介绍
CandleStickChartView *chartView = [[CandleStickChartView alloc] init];
//设置偏移
[chartView setExtraOffsetsWithLeft:10 top:10 right:10 bottom:10];
//开启border
chartView.drawBordersEnabled = YES;
chartView.borderLineWidth = .5f;
chartView.borderColor = UIColor.blackColor;
//设置背景
chartView.drawGridBackgroundEnabled = NO;
chartView.gridBackgroundColor = [UIColor grayColor];
//无内容显示
chartView.noDataText = @"";
//关闭描述
chartView.chartDescription.enabled = NO;
chartView.chartDescription.text = @"tiny`s kLineChart demo";
//关闭图例
chartView.legend.enabled = NO;
//缩放
chartView.scaleXEnabled = YES;
chartView.scaleYEnabled = NO;
chartView.autoScaleMinMaxEnabled = YES;
chartView.highlightPerTapEnabled = YES;
chartView.highlightPerDragEnabled = NO;
chartView.pinchZoomEnabled = NO; //手势捏合
chartView.dragEnabled = YES; //开启拖拽
chartView.dragDecelerationFrictionCoef = 0.5; //0 1 惯性
chartView.doubleTapToZoomEnabled = NO;
//代理
chartView.delegate = self;
//leftAxis
ChartYAxis *rightAxis = chartView.rightAxis;
rightAxis.enabled = YES;
rightAxis.labelPosition = YAxisLabelPositionInsideChart;
rightAxis.drawGridLinesEnabled = YES;
rightAxis.gridLineDashLengths = @[@2,@4];
rightAxis.labelTextColor = UIColor.blackColor;
rightAxis.labelFont = [UIFont systemFontOfSize:10];
rightAxis.decimals = 2;
rightAxis.labelCount = 6; //设置显示最大点数
rightAxis.forceLabelsEnabled = YES; //强制label个数
// leftAxis.inverted = YES;
//设置样式
LeftAxisFormatter *leftFormatter = [LeftAxisFormatter new];
leftFormatter.digital = 2;
rightAxis.valueFormatter = leftFormatter;
//rightAxis
ChartYAxis *leftAxis = chartView.leftAxis;
leftAxis.enabled = NO;
//xAxis
ChartXAxis *xAxis = chartView.xAxis;
xAxis.enabled = YES;
xAxis.labelPosition = XAxisLabelPositionBottom;
xAxis.labelCount = 2; //设置显示点数
xAxis.forceLabelsEnabled = YES; //强制label个数
xAxis.avoidFirstLastClippingEnabled = YES; //避免文字显示不全 这个属性很重要
xAxis.granularityEnabled = YES; //设置重复不显示
//不画线
xAxis.drawGridLinesEnabled = NO;
xAxis.spaceMin = 0.5;
xAxis.spaceMax = 0.5;
CandleChartDataEntry代码每个柱子图形
NSMutableArray *array = [NSMutableArray array];
for (int i = 0; i < datas.count; i++) {
NSDictionary *dict = datas[i];
double high = [dict[@"dbHighPrice"] doubleValue];
double low = [dict[@"dbLowPrice"] doubleValue];
double open = [dict[@"dbOpenPrice"] doubleValue];
double close = [dict[@"dbClosePrice"] doubleValue];
CandleChartDataEntry *entry = [[CandleChartDataEntry alloc] initWithX:(i) shadowH:high shadowL:low open:open close:close];
[array addObject:entry];
}
CandleChartDataSet代码所有的柱子的集合
CandleChartDataSet *set = [[CandleChartDataSet alloc] initWithEntries:array label:@"kLine DataSet"];
//下降颜色 是否填充填充
set.decreasingColor = UIColorHex(0x32BE89);
set.decreasingFilled = YES;
//上升颜色 是否填充填充
set.increasingColor = UIColorHex(0xFD4C60);
set.increasingFilled = YES;
//显示美国线
//set.showCandleBar = NO;
//阴影线的宽度 颜色跟随
set.shadowWidth = 0.7;
set.shadowColorSameAsCandle = YES;
//k线柱间隙
set.barSpace = 0.15;
//是否现在十字标识
set.drawHorizontalHighlightIndicatorEnabled = NO;
set.drawVerticalHighlightIndicatorEnabled = NO;
//轴线方向
set.axisDependency = AxisDependencyRight;
//不显数字
set.drawValuesEnabled = NO;
CandleChartData
//创建数据
CandleChartData *candleData = [[CandleChartData alloc] initWithDataSet:set];
//赋值
self.chartView.data = candleData;
一些需要注意的点：
1.显示美国线
CandleChartDataSet:
set.showCandleBar = NO
2.影线的颜色跟随k线，这样就会根据k线值自动变成绿色或者红色
CandleChartDataSet:
set.shadowWidth = 0.7;
set.shadowColorSameAsCandle = YES;
3.k线上升颜色，是否填充等属性，用来设置上升颜色下降颜色，是否是空心实心k线
CandleChartDataSet:
//下降颜色 是否填充填充
set.decreasingColor = UIColorHex(0x32BE89);
set.decreasingFilled = YES;
//上升颜色 是否填充填充
set.increasingColor = UIColorHex(0xFD4C60);
set.increasingFilled = NO;
4.是否显示k线值
CandleChartDataSet:
//不显数字
set.drawValuesEnabled = NO;
5.是否显示十字光标
CandleChartDataSet:
set.drawHorizontalHighlightIndicatorEnabled = NO;
set.drawVerticalHighlightIndicatorEnabled = NO;
6.轴线方向 AxisDependencyRight 这样当我们滑动k线的时候k线会根据当前k线最大值和最小值调整缩放比例
CandleChartDataSet:
//轴线方向
set.axisDependency = AxisDependencyRight;
7.k线设置缩放比例，最大缩放值 最小缩放值
//最大缩放值 最小缩放值 y轴不缩放 minScl maxScl根据实际情况调整
[self.chartView setScaleMinima:minScl scaleY:1];
[self.chartView.viewPortHandler setMaximumScaleX:maxScl];
8.当前缩放比例设置
CGAffineTransform srcMatrix = _chartView.viewPortHandler.touchMatrix;
//scl根据实际情况设置当前缩放比例
srcMatrix.a = scl;
[self.chartView.viewPortHandler refreshWithNewMatrix:srcMatrix chart:self.chartView invalidate:YES];
9.k线移动到指定位置 第一次需要滚动到最新值
//开局移动到最右边xMax为最大x轴值
[self.chartView moveViewToX:self.chartView.data.xMax];
10.选中k线，拿到当前选中的点的x轴坐标，以便于拿到选中的model
//k线代理方法
-(void)chartValueSelected:(ChartViewBase *)chartView entry:(ChartDataEntry *)entry highlight:(ChartHighlight *)highlight{
NSInteger index = highlight.x;
//index为当前选中的x值
if(index < self.datas.count){
//根据当前的index能拿到对应的数据模型
Model *model = self.datas[index];
}
}
其他待续
