Question

I’m using Core Plot to do some graphing in an iOS app. I’m in the midst of configuring the axes, and I’m getting strange white lines below the X and to the left of the Y axis, as seen in the following picture:

My set-up code for the graph is as follows:

// 1 - Create the graph
CPTGraph *graph = [[CPTXYGraph alloc] initWithFrame:self.barHostView.bounds];
graph.plotAreaFrame.masksToBorder = NO;
self.barHostView.hostedGraph = graph;    
// 2 - Configure the graph    
[graph applyTheme:[CPTTheme themeNamed:kCPTPlainBlackTheme]];    
graph.paddingBottom = 30.0f;      
graph.paddingLeft  = 30.0f;
graph.paddingTop    = -1.0f;
graph.paddingRight  = -5.0f;
// 3 - Set up styles
CPTMutableTextStyle *titleStyle = [CPTMutableTextStyle textStyle];
titleStyle.color = [CPTColor whiteColor];
titleStyle.fontName = @"Helvetica-Bold";
titleStyle.fontSize = 16.0f;
// 4 - Set up title
graph.title = [NSString stringWithFormat:@"Usage on %@", self.turnout];
graph.titleTextStyle = titleStyle;
graph.titlePlotAreaFrameAnchor = CPTRectAnchorTop;
graph.titleDisplacement = CGPointMake(0.0f, -16.0f);

// 5 - Set up plot space
CGFloat xMin = -1.5f;
CGFloat xMax = [self.points count] + 2;
CGFloat yMin = 0.0f;
self.yMax = [[self greatestFlowValue] floatValue] * 1.4;

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

plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(xMin) length:CPTDecimalFromFloat(xMax)];
plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(yMin) length:CPTDecimalFromFloat(self.yMax)];

CPTMutablePlotRange *yRange = [plotSpace.yRange mutableCopy];
[yRange expandRangeByFactor:CPTDecimalFromCGFloat(1.65f)];        
plotSpace.yRange = yRange;    

I more ore less copied this out of a tutorial and then modified it. In the walk-through, they didn’t have labels on the axes — which they had set at the left and bottom of the screen.

Can anyone explain what is causing these extra lines and how I might disable them? They only appear on my Bar Charts… I have other graphs that use scatter plots without any similar results.

Answer 1

It looks like you have a border on you plotAreaFrame(set by the theme), try removing it after applying the theme:

graph.plotAreaFrame.borderLineStyle = nil;