更改Core Plot饼图标题的外观 [英] Change the appearance of the title of a Core Plot pie chart

问题描述

我想在我的饼图中使用纯黑色背景，我使用Core Plot生成。我有很好的图表渲染，但标题是在黑色背景上很难看到的默认黑色。我知道这是显示，因为当我改变主题时，我可以看到它黑色。任何人都可以告诉我如何改变文字颜色，就像我对数据标签做的那样？

I would like to use a plain black background to my pie chart which I generate using Core Plot. I have the chart rendering nicely but the title is in a default blackColor which is hard to see on a black background. I know it's displaying because when I change the theme I can see it in black. Can anyone tell me how to change the text colour as I did with the data labels?

这是我的代码片段...

Here is a snippet of my code...

    graph = [[CPTXYGraph alloc] initWithFrame:self.view.bounds];
    CPTGraphHostingView *hostingView = (CPTGraphHostingView*)self.view;
    hostingView.hostedGraph = graph;

    CPTPieChart *pieChart = [[CPTPieChart alloc] init];
    pieChart.dataSource = self;
    pieChart.pieRadius = 80.0;
    pieChart.identifier = @"PieChart1";
    pieChart.startAngle = M_PI_4;
    pieChart.sliceDirection = CPTPieDirectionCounterClockwise;

    [graph addPlot:pieChart];
    graph.title = @"Proportion of Sessions per Sport";

}

-(CPTLayer *)dataLabelForPlot:(CPTPlot *)plot recordIndex:(NSUInteger)index {
    static CPTMutableTextStyle *whiteText = nil;
    if (!whiteText) {
        whiteText = [[CPTMutableTextStyle alloc] init];
        whiteText.color = [CPTColor whiteColor];
    }

    CPTLayer *layer = [[CPTLayer alloc] initWithFrame:CGRectMake(50, 50, 100, 20)];
    CPTTextLayer *newLayer = nil;
    newLayer = [[CPTTextLayer alloc] initWithText:[NSString stringWithFormat:@"%@", [pieLabels objectAtIndex:index]] style:whiteText];
    [layer addSublayer:newLayer];
    return newLayer;
}

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

-(NSNumber *)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index {
    return [self.pieData objectAtIndex:index];
}

-(NSString *)legendTitleForPieChart:(CPTPieChart *)pieChart recordIndex:(NSUInteger)index {
    return [NSString stringWithFormat:@"Pie Slice %u", index];
}

非常感谢您提供的任何协助/建议/链接...

Many thanks in advance for any assistance/advice/links offered...

推荐答案

我在Core Plot示例代码中发现了它在我面前盯着我的全部答案...

I found the answer it was staring me in the face the whole time in the Core Plot sample code...

对于其他人在这个问题上磕磕绊绊的答案是：

For anyone else stumbling upon this question here is the answer:

CPTMutableTextStyle *whiteText = [CPTMutableTextStyle textStyle];
    whiteText.color = [CPTColor whiteColor];
    graph.titleTextStyle = whiteText;
    graph.title = @"Your Title Here...";

这篇关于更改Core Plot饼图标题的外观的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！