Question

您好我正在使用核心图进行散点图绘制。我正在针对日期时间绘制数据（最多3位小数）。关于yaxis的数据和xaxis上的日期时间。对于某些数据值，yaxis Custom tick标签不可见。

screenshot

以下是代码

CPTXYGraph *scatterGraph = [[CPTXYGraph alloc] initWithFrame:graphView.bounds];
graphView.hostedGraph = scatterGraph;

NSMutableArray *plotdataArray = [[NSMutableArray alloc] init];
NSMutableArray *timedataArray = [[NSMutableArray alloc] init];
plotdataArray = arrPlotData;
timedataArray = arrTimeData;

//create data plot
self.dataSourceLinePlot = [[CPTScatterPlot alloc]init];
self.dataSourceLinePlot.identifier = NSLocalizedString(@"Glucose Trend Chart", nil);
self.dataSourceLinePlot.cachePrecision = CPTPlotCachePrecisionDecimal;

CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *) scatterGraph.defaultPlotSpace;

//assign data to chartdata class
CGM_GlucoseChartData *chartDataObj = [[CGM_GlucoseChartData alloc] initWithView:self.dataSourceLinePlot];
chartDataObj.parent = self;
self.dataSourceLinePlot.dataSource = chartDataObj;
chartDataObj.dataForPlot = arrPlotData;
chartDataObj.arrTimeData = timedataArray;
[scatterGraph addPlot:self.dataSourceLinePlot];

scatterGraph.plotAreaFrame.frame = scatterGraph.bounds;

//add padding to graphview
scatterGraph.plotAreaFrame.paddingTop    = 0;
scatterGraph.plotAreaFrame.paddingRight  = 0;
scatterGraph.plotAreaFrame.paddingBottom = 90;
scatterGraph.plotAreaFrame.paddingLeft   = 66;
scatterGraph.plotAreaFrame.masksToBorder = YES;

//add linestyle to graph
CPTMutableLineStyle *lineStyle = [self.dataSourceLinePlot.dataLineStyle mutableCopy];
lineStyle.lineWidth              = 1.0;
lineStyle.lineColor              = [CPTColor blueColor];
CPTPlotSymbol *plotSymbol = [CPTPlotSymbol ellipsePlotSymbol];
plotSymbol.fill = [CPTFill fillWithColor:[CPTColor whiteColor]];
plotSymbol.size = CGSizeMake(1.0f, 1.0f);
self.dataSourceLinePlot.dataLineStyle = lineStyle;

//calculate min and max values from array
float yMax = [[arrPlotData valueForKeyPath:@"@max.self"] floatValue];
float yMin = [[arrPlotData valueForKeyPath:@"@min.self"] floatValue];
NSUInteger xMax = timedataArray.count;

//create axis set for graph
CPTXYAxisSet *axisSet = (CPTXYAxisSet *)scatterGraph.axisSet;
// Configure Line-Style //
CPTMutableLineStyle *tickLineStyle = [CPTMutableLineStyle lineStyle];
tickLineStyle.lineWidth = 1.0f;
tickLineStyle.lineColor = [CPTColor blackColor];
axisSet.yAxis.majorTickLineStyle = tickLineStyle;
axisSet.xAxis.majorTickLineStyle = tickLineStyle;


// y-axis labels
CPTXYAxis *y = axisSet.yAxis;
y.axisConstraints = [CPTConstraints constraintWithLowerOffset:0.0];
y.orthogonalCoordinateDecimal = CPTDecimalFromUnsignedInteger(0.0);

y.labelingPolicy = CPTAxisLabelingPolicyNone;

//set axis title
NSString *temp = NSLocalizedString(@"Glucose", nil);
y.title = [NSString stringWithFormat:@"%@ (%@)",temp,unitType];
y.titleOffset = 52;


// x-axis labels
CPTXYAxis *x = axisSet.xAxis;


//set axis title
x.title = NSLocalizedString(@"Time (Hour)", nil);
x.titleOffset = 75;
x.axisConstraints = [CPTConstraints constraintWithLowerOffset:0.0];
x.orthogonalCoordinateDecimal = CPTDecimalFromUnsignedInteger(0.0);
x.labelingPolicy = CPTAxisLabelingPolicyNone;
if(plotdataArray.count == 0) {
    plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromInt(0) length:CPTDecimalFromInteger(1)];
    plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromInt(0) length:CPTDecimalFromInteger(1)];
}
else{

        float centerLocation = (yMax+yMin) / 2;
        float ytemp1 = (yMin +centerLocation) / 2;
        float ytemp2 = (yMax+centerLocation) / 2;

        //if differnce between min and max values is 0.1
        if((yMax - yMin) == 0.001) {
            customTickLocations =  [NSArray arrayWithObjects:
                                    [NSString stringWithFormat:@"%.3f",yMin],
                                    [NSString stringWithFormat:@"%.3f",yMax],nil];

            yAxisLabels = [NSArray arrayWithObjects:
                           [NSString stringWithFormat:@"%.3f",yMin],
                           [NSString stringWithFormat:@"%.3f",yMax],nil];
            tempVal = yMax/4;
        }
        else{
            if(ytemp1 == centerLocation || ytemp2 == centerLocation) {
                customTickLocations =  [NSArray arrayWithObjects:
                                        [NSString stringWithFormat:@"%.3f",yMin],
                                        [NSString stringWithFormat:@"%.3f",centerLocation],
                                        [NSString stringWithFormat:@"%.3f",yMax],nil];



                yAxisLabels = [NSArray arrayWithObjects:
                               [NSString stringWithFormat:@"%.3f",yMin],
                               [NSString stringWithFormat:@"%.3f",centerLocation],
                               [NSString stringWithFormat:@"%.3f",yMax],nil];
                tempVal = yMax/4;;

            }
            else{
                customTickLocations =  [NSArray arrayWithObjects:
                                        [NSString stringWithFormat:@"%.3f",yMin],
                                        [NSString stringWithFormat:@"%.3f",ytemp1],
                                        [NSString stringWithFormat:@"%.3f",centerLocation],
                                        [NSString stringWithFormat:@"%.3f",ytemp2],
                                        [NSString stringWithFormat:@"%.3f",yMax],nil];



                yAxisLabels = [NSArray arrayWithObjects:
                               [NSString stringWithFormat:@"%.3f",yMin],
                               [NSString stringWithFormat:@"%.3f",ytemp1],
                               [NSString stringWithFormat:@"%.3f",centerLocation],
                               [NSString stringWithFormat:@"%.3f",ytemp2],
                               [NSString stringWithFormat:@"%.3f",yMax],nil];
                tempVal = (yMax-ytemp2)/2;
            }
        }
        }

    NSUInteger labelLocation = 0;

    NSMutableArray *customLabels = [NSMutableArray arrayWithCapacity:[yAxisLabels count]];
    for (NSNumber *tickLocation in customTickLocations) {
        CPTAxisLabel *newLabel = [[CPTAxisLabel alloc] initWithText: [yAxisLabels objectAtIndex:labelLocation++] textStyle:y.labelTextStyle];
        newLabel.tickLocation = [tickLocation decimalValue];
        newLabel.offset = y.labelOffset + y.majorTickLength;
        [customLabels addObject:newLabel];
    }
    y.majorTickLocations = [NSSet setWithArray:customTickLocations];
    y.axisLabels =  [NSSet setWithArray:customLabels];

    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    dateFormatter.dateFormat = @"dd-MM (HH:mm)";
    [dateFormatter setTimeZone:[NSTimeZone timeZoneWithName:@"GMT+0:00"]];

    NSMutableSet *xLabels = [NSMutableSet setWithCapacity:timedataArray.count];
    NSMutableSet *xLocations = [NSMutableSet setWithCapacity:timedataArray.count];

    NSUInteger maximumValue = 0;
    if(timedataArray.count > 5 && timedataArray.count < 15) {
        maximumValue = xMax - 1;
    }
    else {
        maximumValue = xMax - (timedataArray.count/15);
    }

    if(timedataArray.count <= 5) {
        for (NSInteger j = 0; j < timedataArray.count; j ++) {

            CPTAxisLabel *label = [[CPTAxisLabel alloc] initWithText:[dateFormatter stringFromDate:timedataArray[j]] textStyle:x.labelTextStyle];
            NSDecimal location = CPTDecimalFromInteger(j);
            label.tickLocation = location;

            if (label)
            {
                [xLabels addObject:label];
                label.offset = 5.0f;
                [xLocations addObject:[dateFormatter stringFromDate:timedataArray[j]]];
            }

        }
        x.majorTickLocations = xLocations;
        x.axisLabels = xLabels;

    }
    else {
        //if(timedataArray.count < 15) {
        NSInteger centerLocation = timedataArray.count / 2;
        NSInteger temp1 = centerLocation / 2;
        NSInteger temp2 = (timedataArray.count-centerLocation) / 2;

        NSArray *customTickLocations =  [NSArray arrayWithObjects:
                                         [NSString stringWithFormat:@"%.1f",0.0],
                                         [NSString stringWithFormat:@"%.1ld",(long)temp1],
                                         [NSString stringWithFormat:@"%.1ld",(long)centerLocation],
                                         [NSString stringWithFormat:@"%.1ld",(long)centerLocation + temp2],
                                         [NSString stringWithFormat:@"%.1lu",(unsigned long)maximumValue],nil];

        NSArray *xAxisLabels = [NSArray arrayWithObjects:
                                [NSString stringWithFormat:@"%@",[dateFormatter stringFromDate:timedataArray[0]]],
                                [NSString stringWithFormat:@"%@",[dateFormatter stringFromDate:timedataArray[temp1]]],
                                [NSString stringWithFormat:@"%@",[dateFormatter stringFromDate:timedataArray[centerLocation]]],
                                [NSString stringWithFormat:@"%@",[dateFormatter stringFromDate:timedataArray[centerLocation + temp2]]],
                                [NSString stringWithFormat:@"%@",[dateFormatter stringFromDate:timedataArray[maximumValue]]],nil];


        x.majorTickLocations = [NSSet setWithArray:customTickLocations];

        NSUInteger labelLocation = 0;

        NSMutableArray *customLabels = [NSMutableArray arrayWithCapacity:[xAxisLabels count]];
        for (NSNumber *tickLocation in customTickLocations) {
            CPTAxisLabel *newLabel = [[CPTAxisLabel alloc] initWithText: [xAxisLabels objectAtIndex:labelLocation++] textStyle:x.labelTextStyle];
            newLabel.tickLocation = [tickLocation decimalValue];
            newLabel.offset = x.labelOffset + x.majorTickLength;
            [customLabels addObject:newLabel];
        }

        x.axisLabels =  [NSSet setWithArray:customLabels];
    }

    //rotate the x axis label
    x.labelRotation = M_PI/3;

    //create plot space and assign range for graph
    plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromInt(0) length:CPTDecimalFromInteger(xMax)];

    if(timedataArray.count == 1 || yMax == yMin) {
        if(yMax == 0) {
            plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(0.0)
                                                            length:CPTDecimalFromFloat(1.0)];
        }
        else{
            if(tempVal == 0) {
                tempVal = yMax/4;
            }
            plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(0.0)
                                                            length:CPTDecimalFromString([NSString stringWithFormat:@"%.2f",yMax+tempVal])];
        }

    }
    else{
        plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromString([NSString stringWithFormat:@"%.2f",yMin])
                                                        length:CPTDecimalFromString([NSString stringWithFormat:@"%.2f",(yMax-yMin)+tempVal])];
    }


}
[self.dataSourceLinePlot reloadData];

请向我的代码提出一些问题

核心绘图问题y轴绘图点不可见

0 个答案: