Question

我正在试验iOS的Core Plot库。我设法用我的信息显示图表，但是我无法按照自己的意愿个性化可视化我正在尝试使用简单的散点图来显示用户白天在两个日期之间行进的距离。我已经设法为绘图创建数据，但我很难个性化情节，也许有人使用过这个lib可以帮助我;）
我的问题是：
- 如果我只显示x轴和y轴的正侧，我就看不到标签了 - 例如，如果两个日期之间有31天，则x轴从0到30.如何更改标签以显示日期，例如startDate + x。这就是我到目前为止所做的：

@interface DistanceChart : CPGraphHostingView <CPPlotDataSource> {
    CPXYGraph *graph;
    NSMutableArray *dataForPlot;
    RouteManager *routeManager;
    NSDate *startDate;
    NSDate *endDate;
}

@property (nonatomic, retain) NSMutableArray *dataForPlot;
@property (nonatomic, retain) RouteManager *routeManager;
@property (nonatomic, retain) NSDate *startDate;
@property (nonatomic, retain) NSDate *endDate;

- (void)initPlot;

@end



@implementation DistanceChart
@synthesize dataForPlot;
@synthesize routeManager;
@synthesize startDate;
@synthesize endDate;

- (void)initPlot {
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:@"dd-MM-yyyy"];
    self.startDate = [dateFormatter dateFromString:@"01-05-2011"];
    self.endDate = [dateFormatter dateFromString:@"31-05-2011"];

    //get the data
    self.dataForPlot = [routeManager getTotalDistanceByDay:routeManager.routes from:startDate to:endDate];
    NSLog(@"Data: %@", dataForPlot);


    graph = [[CPXYGraph alloc] initWithFrame:CGRectZero];
    self.hostedGraph = graph;

    graph.paddingLeft = 5;
    graph.paddingTop = 5;
    graph.paddingRight = 5;
    graph.paddingBottom = 5;

    // Setup plot space
    int days = [endDate timeIntervalSinceDate:startDate] / 60 / 60 / 24 + 1;

    CPXYPlotSpace *plotSpace = (CPXYPlotSpace *)graph.defaultPlotSpace;
    plotSpace.allowsUserInteraction = YES;
    plotSpace.xRange = [CPPlotRange plotRangeWithLocation:CPDecimalFromFloat(0) length:CPDecimalFromFloat(days)];
    plotSpace.yRange = [CPPlotRange plotRangeWithLocation:CPDecimalFromFloat(0) length:CPDecimalFromFloat(15)]; //TODO: set maximum Y according to max distance

    // Axes
    CPXYAxisSet *axisSet = (CPXYAxisSet *)graph.axisSet;
    CPXYAxis *x = axisSet.xAxis;
    x.majorIntervalLength = CPDecimalFromString(@"1");
    x.orthogonalCoordinateDecimal = CPDecimalFromString(@"0");
    x.minorTicksPerInterval = 1;

    CPXYAxis *y = axisSet.yAxis;
    y.majorIntervalLength = CPDecimalFromString(@"1");
    y.minorTicksPerInterval = 1;
    y.orthogonalCoordinateDecimal = CPDecimalFromString(@"0");
    x.labelRotation = M_PI/8;

    // Create a green plot area
    CPScatterPlot *dataSourceLinePlot = [[[CPScatterPlot alloc] init] autorelease];
    dataSourceLinePlot.identifier = @"Green Plot";

    CPMutableLineStyle *lineStyle = [[dataSourceLinePlot.dataLineStyle mutableCopy] autorelease];
    lineStyle.lineWidth = 2.f;
    lineStyle.lineColor = [CPColor greenColor];

    dataSourceLinePlot.dataLineStyle = lineStyle;
    dataSourceLinePlot.dataSource = self;

    // Put an area gradient under the plot above
    CPColor *areaColor = [CPColor colorWithComponentRed:0.3 green:1.0 blue:0.3 alpha:0.8];
    CPGradient *areaGradient = [CPGradient gradientWithBeginningColor:areaColor endingColor:[CPColor clearColor]];
    areaGradient.angle = -90.0f;
    CPFill *areaGradientFill = [CPFill fillWithGradient:areaGradient];
    dataSourceLinePlot.areaFill = areaGradientFill;
    dataSourceLinePlot.areaBaseValue = CPDecimalFromString(@"1.75");

    // Animate in the new plot, as an example
    dataSourceLinePlot.opacity = 0.0f;
    dataSourceLinePlot.cachePrecision = CPPlotCachePrecisionDecimal;
    [graph addPlot:dataSourceLinePlot];

    CABasicAnimation *fadeInAnimation = [CABasicAnimation animationWithKeyPath:@"opacity"];
    fadeInAnimation.duration = 1.0f;
    fadeInAnimation.removedOnCompletion = NO;
    fadeInAnimation.fillMode = kCAFillModeForwards;
    fadeInAnimation.toValue = [NSNumber numberWithFloat:1.0];
    [dataSourceLinePlot addAnimation:fadeInAnimation forKey:@"animateOpacity"];
}

#pragma mark -
#pragma mark Plot Data Source Methods

- (NSUInteger)numberOfRecordsForPlot:(CPPlot *)plot 
{
    return [dataForPlot count];
}

- (NSNumber *)numberForPlot:(CPPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index 
{
    NSDecimalNumber *num = [[dataForPlot objectAtIndex:index] valueForKey:(fieldEnum == CPScatterPlotFieldX ? @"x" : @"y")];

    return num;
}

- (CPLayer *)dataLabelForPlot:(CPPlot *)plot recordIndex:(NSUInteger)index
{
    return nil;
}

- (void)dealloc {
    [dataForPlot release];
    [routeManager release];
    [startDate release];
    [endDate release];

    [super dealloc];
}

@end

Answer 1

您可能需要增加填充以显示标签。您可能还需要在plotAreaFrame上添加填充。

Core Plot附带了几个示例程序（“DatePlot”和“MinorTickLabels”），展示了如何在轴上设置日期和时间的格式。

核心情节：个性化情节

1 个答案: