Question

根据库Core Plot中提供的示例 RealTime ，我尝试在我的项目中重新实现它。

我可以更新y axis，添加符号，绘制标签等等。但我完全无法绘制线条。

CPTMutableLineStyle对象似乎已正确即时并正确设置为CPTGraph对象，但未在图表中呈现

以下是我在图表中添加线条样式的方法

CPTMutableLineStyle *lineStyle = [CPTMutableLineStyle lineStyle]; // [dataSourceLinePlot.dataLineStyle mutableCopy];
lineStyle.lineWidth              = 3.0;
lineStyle.lineColor              = [CPTColor greenColor];
dataSourceLinePlot.dataLineStyle = lineStyle;

enter image description here

这是完整的类代码

#import "TUTSimpleScatterPlot.h"

const double kFrameRate         = 5.0;  // frames per second
const double kAlpha             = 0.15; // smoothing constant
const NSUInteger kMaxDataPoints = 21;
NSString *kPlotIdentifier       = @"Data Source Plot";

@implementation TUTSimpleScatterPlot


// Initialise the scatter plot in the provided hosting view with the provided data.
// The data array should contain NSValue objects each representing a CGPoint.
-(id)initWithHostingView:(CPTGraphHostingView *)hostingView andData:(NSMutableArray *)data
{
    self = [super init];

    if ( self != nil ) {
        self.hostingView = hostingView;
        self.graphData = data;
        self.graph = nil;
    }

    return self;
}





-(void)initialisePlot
{
    self.graphData = [NSMutableArray array];
    CGRect bounds = self.hostingView.bounds;

    CPTGraph *graph = [[CPTXYGraph alloc] initWithFrame:bounds] ;


    [self.hostingView setHostedGraph:graph];

    graph.title = @"Measure";
    CPTMutableTextStyle *textStyle = [CPTMutableTextStyle textStyle];
    textStyle.color                = [CPTColor grayColor];
    textStyle.fontName             = @"Helvetica-Bold";
    textStyle.fontSize             = round(bounds.size.height / (CGFloat)20.0);
    graph.titleTextStyle           = textStyle;
    graph.titleDisplacement        = CGPointMake( 0.0f, round(bounds.size.height / (CGFloat)18.0) ); // Ensure that title displacement falls on an integral pixel
    graph.titlePlotAreaFrameAnchor = CPTRectAnchorTop;

    CGFloat boundsPadding = round(bounds.size.width / (CGFloat)20.0); // Ensure that padding falls on an integral pixel

    graph.paddingLeft = boundsPadding;

    if ( graph.titleDisplacement.y > 0.0 ) {
        graph.paddingTop = graph.titleDisplacement.y * 2;
    }
    else {
        graph.paddingTop = boundsPadding;
    }

    graph.paddingRight  = boundsPadding;
    graph.paddingBottom = boundsPadding;





    graph.plotAreaFrame.paddingTop    = 15.0;
    graph.plotAreaFrame.paddingRight  = 15.0;
    graph.plotAreaFrame.paddingBottom = 55.0;
    graph.plotAreaFrame.paddingLeft   = 55.0;

    // Grid line styles
    CPTMutableLineStyle *majorGridLineStyle = [CPTMutableLineStyle lineStyle];
    majorGridLineStyle.lineWidth = 0.75;
    majorGridLineStyle.lineColor = [[CPTColor colorWithGenericGray:0.2] colorWithAlphaComponent:0.75];

    CPTMutableLineStyle *minorGridLineStyle = [CPTMutableLineStyle lineStyle];
    minorGridLineStyle.lineWidth = 0.25;
    minorGridLineStyle.lineColor = [[CPTColor whiteColor] colorWithAlphaComponent:0.1];

    // Axes
    // X axis
    CPTXYAxisSet *axisSet = (CPTXYAxisSet *)graph.axisSet;
    CPTXYAxis *x          = axisSet.xAxis;
    x.labelingPolicy              = CPTAxisLabelingPolicyAutomatic;
    x.orthogonalCoordinateDecimal = CPTDecimalFromUnsignedInteger(0);
    x.majorGridLineStyle          = majorGridLineStyle;
    x.minorGridLineStyle          = minorGridLineStyle;
    x.minorTicksPerInterval       = 9;
    x.title                       = @"X Axis";
    x.titleOffset                 = 35.0;
    NSNumberFormatter *labelFormatter = [[NSNumberFormatter alloc] init];
    labelFormatter.numberStyle = NSNumberFormatterNoStyle;
    x.labelFormatter           = labelFormatter;

    // Y axis
    CPTXYAxis *y = axisSet.yAxis;
    y.labelingPolicy              = CPTAxisLabelingPolicyAutomatic;
    y.orthogonalCoordinateDecimal = CPTDecimalFromUnsignedInteger(0);
    y.majorGridLineStyle          = majorGridLineStyle;
    y.minorGridLineStyle          = minorGridLineStyle;
    y.minorTicksPerInterval       = 3;
    y.labelOffset                 = 5.0;
    y.title                       = @"Y Axis";
    y.titleOffset                 = 30.0;
    y.axisConstraints             = [CPTConstraints constraintWithLowerOffset:0.0];

    // Rotate the labels by 45 degrees, just to show it can be done.
    x.labelRotation = M_PI * 0.25;

    // Create the plot
    CPTScatterPlot *dataSourceLinePlot = [[CPTScatterPlot alloc] init];
    dataSourceLinePlot.identifier     = kPlotIdentifier;
    dataSourceLinePlot.cachePrecision = CPTPlotCachePrecisionDouble;
    //    dataSourceLinePlot.interpolation = CPTScatterPlotInterpolationCurved;

    CPTMutableLineStyle *lineStyle = [CPTMutableLineStyle lineStyle]; // [dataSourceLinePlot.dataLineStyle mutableCopy];
    lineStyle.lineWidth              = 3.0;
    lineStyle.lineColor              = [CPTColor greenColor];
    dataSourceLinePlot.dataLineStyle = lineStyle;

    CPTMutableLineStyle *symbolLineStyle = [CPTMutableLineStyle lineStyle];
    symbolLineStyle.lineColor = [[CPTColor blackColor] colorWithAlphaComponent:0.5];
    CPTPlotSymbol *plotSymbol = [CPTPlotSymbol ellipsePlotSymbol];
    plotSymbol.fill               = [CPTFill fillWithColor:[[CPTColor blueColor] colorWithAlphaComponent:0.5]];
    plotSymbol.lineStyle          = symbolLineStyle;
    plotSymbol.size               = CGSizeMake(10.0, 10.0);
    dataSourceLinePlot.plotSymbol = plotSymbol;

    dataSourceLinePlot.dataSource = self;
    [graph addPlot:dataSourceLinePlot];

    // Plot space
    CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *)graph.defaultPlotSpace;
    plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromUnsignedInteger(0) length:CPTDecimalFromUnsignedInteger(kMaxDataPoints - 1)];
    plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromUnsignedInteger(0) length:CPTDecimalFromUnsignedInteger(1)];


    self.graph = graph;

    self.dataTimer = [NSTimer timerWithTimeInterval:1.0 / kFrameRate
                                         target:self
                                       selector:@selector(newData:)
                                       userInfo:nil
                                        repeats:YES];
    [[NSRunLoop mainRunLoop] addTimer:self.dataTimer forMode:NSDefaultRunLoopMode];


}

#pragma mark -
#pragma mark Timer callback

-(void)newData:(NSTimer *)theTimer
{
    CPTGraph *theGraph = self.graph;
    CPTPlot *thePlot   = [theGraph plotWithIdentifier:kPlotIdentifier];

    if ( thePlot ) {
//        if ( self.graphData.count >= kMaxDataPoints - 5 ) {
//            [self.graphData removeObjectAtIndex:0];
//            [thePlot deleteDataInIndexRange:NSMakeRange(0, 1)];
//        }

        CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *)theGraph.defaultPlotSpace;
        NSUInteger location       = (_currentIndex >= kMaxDataPoints ? _currentIndex - kMaxDataPoints + 5 : 0);
        plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromUnsignedInteger(location)
                                                        length:CPTDecimalFromUnsignedInteger(kMaxDataPoints - 1)];

        _currentIndex++;

        NSNumber * num;
        if (_currentIndex == 1) {

            num = [NSNumber numberWithDouble: 5 + (arc4random() % 15) ];
        } else {


            NSLog(@"lastVal: %d", [[self.graphData lastObject] intValue]);
            float low_bound = (1 - kAlpha) * [[self.graphData lastObject] floatValue];
            float high_bound = (1.01 + kAlpha) * [[self.graphData lastObject] floatValue];
            float random = (((float)arc4random()/0x100000000)*(high_bound-low_bound)+low_bound);

            NSLog(@"random: %f", random);
            num = [NSNumber numberWithDouble:random];
        }
        // Update y range if necessary
        if (_currentIndex < kMaxDataPoints) {
            int maxValue = -1;
            for (int i = self.graphData.count -1 ; (i >= 0); i--) {
                if ([[self.graphData objectAtIndex:i] intValue] > maxValue) {
                    maxValue = [[self.graphData objectAtIndex:i] intValue];
                }
            }
            plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromUnsignedInteger(0) length:CPTDecimalFromUnsignedInteger(maxValue + 1)];
        } else if (_currentIndex >= kMaxDataPoints) {
            int maxValue = -1;
            for (int i = self.graphData.count -1 ; (i >= self.graphData.count - kMaxDataPoints + 2); i--) {
                if ([[self.graphData objectAtIndex:i] intValue] > maxValue) {
                    maxValue = [[self.graphData objectAtIndex:i] intValue];
                }
            }
            plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromUnsignedInteger(0) length:CPTDecimalFromUnsignedInteger(maxValue + 1)];
        }


        [self.graphData addObject:num];
        [thePlot insertDataAtIndex:self.graphData.count - 1 numberOfRecords:1];


    }
}

#pragma mark -
#pragma mark Plot Data Source Methods

-(NSUInteger)numberOfRecordsForPlot:(CPTPlot *)plot
{
    return [self.graphData count];
}

-(NSNumber *)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index
{
    NSNumber *num = nil;

    switch ( fieldEnum ) {
        case CPTScatterPlotFieldX:
            num = [NSNumber numberWithUnsignedInteger:index + _currentIndex - self.graphData.count];
            break;

        case CPTScatterPlotFieldY:
            num = [self.graphData objectAtIndex:index];
            break;

        default:
            break;
    }

    return num;
}


@end

有什么想法吗？提示？哈克？

更新1

在我的项目中，我使用了库的1.2版本。我试图回归到1.0版本，现在显示了行。关于如何将我的项目转换为使用上一版本的任何想法？

更新2 *

将Podfile从pod 'CorePlot'更改为pod 'CorePlot', '~> 1.2'似乎有所不同。我的线现在正确绘制了......

Answer 1

通过这种方式使用cocoapods似乎存在差异

pod 'CorePlot'

或通过这种方式

pod 'CorePlot', '~> 1.2'

然后执行pod install

重新安装库

现在该项目能够画线

Core Plot无法画线

1 个答案: