我无法更改饼图位置（我希望它相对于图例更靠左，以便图例不会覆盖饼图）。基本上我想将它向左移动以显示图例。
我尝试修改以下属性（但对饼图位置没有明显影响）：
// pieChartGraph is a CPTPieChart object
pieChartGraph.graph.position = CGPointMake(-100, 0);
// I also tried:
pieChart.position = CGPointMake(-100, 0);
// and also playing with:
pieChart.anchorPoint
这是我得到的，也是我的代码（顺便说一下，标题也没有显示）：
pieChartGraph = [[CPTXYGraph alloc] initWithFrame:self.pieChartgraphHostView.bounds];
self.pieChartgraphHostView.hostedGraph = pieChartGraph;
pieChartGraph.plotAreaFrame.masksToBorder = NO;
pieChartGraph.axisSet = nil;
pieChart.title = @"title"; // <-- BTW, the title does not show either
// 2 - Create chart
pieChart = [[CPTPieChart alloc] init];
pieChart.dataSource = self;
pieChart.delegate = self;
pieChart.pieRadius = self.pieChartgraphHostView.bounds.size.width;
pieChartGraph.delegate = self;
pieChart.identifier = pieChartGraph.title;
pieChart.startAngle = CPTFloat(M_PI_4);
pieChart.sliceDirection = CPTPieDirectionClockwise;
pieChart.borderLineStyle = [CPTLineStyle lineStyle];
// 3 - Create gradient
CPTGradient *overlayGradient = [[CPTGradient alloc] init];
overlayGradient.gradientType = CPTGradientTypeRadial;
overlayGradient = [overlayGradient addColorStop:[[CPTColor blackColor] colorWithAlphaComponent:0.0] atPosition:0.9];
overlayGradient = [overlayGradient addColorStop:[[CPTColor blackColor] colorWithAlphaComponent:0.4] atPosition:1.0];
pieChart.overlayFill = [CPTFill fillWithGradient:overlayGradient];
// 4 - Add chart to graph
pieChart.pieRadius = pieChart.pieRadius / 2.3;
[pieChartGraph addPlot:pieChart];
self.dataForChart = [@[@(self.displayedLastDataPoint.percentageUnder), @(self.displayedLastDataPoint.percentageOver), @(self.displayedLastDataPoint.percentageClean), @(self.displayedLastDataPoint.percentageRemaining)] mutableCopy];
// Add legend
CPTLegend *theLegend = [CPTLegend legendWithGraph:pieChartGraph];
theLegend.numberOfColumns = 1;
theLegend.fill = [CPTFill fillWithColor:[CPTColor whiteColor]];
theLegend.borderLineStyle = [CPTLineStyle lineStyle];
theLegend.entryFill = [CPTFill fillWithColor:[CPTColor lightGrayColor]];
theLegend.entryBorderLineStyle = [CPTLineStyle lineStyle];
theLegend.entryCornerRadius = CPTFloat(3.0);
theLegend.entryPaddingLeft = CPTFloat(3.0);
theLegend.entryPaddingTop = CPTFloat(3.0);
theLegend.entryPaddingRight = CPTFloat(3.0);
theLegend.entryPaddingBottom = CPTFloat(3.0);
theLegend.cornerRadius = 5.0;
theLegend.delegate = self;
pieChartGraph.legend = theLegend;
pieChartGraph.legendAnchor = CPTRectAnchorRight;
CGFloat legendPadding = +(self.view.bounds.size.width / 16);
pieChartGraph.legendDisplacement = CGPointMake(legendPadding, 0.0);
pieChartGraph.graph.position = CGPointMake(-30, 0);