CorePlot inside detail view of Split View

Question

I'm attempting to load a CPXYGraph into the detail view of a split view controller. I'm getting an EXC_BAD_ACCESS when it attempts to display the plot data.

I create a new project based on "Split View-based application". After adding the CorePlot framework I make the following modifications:

1- add a GraphController (.m, .h and .xib). The xib contains a UIView with a subordinate view of type CPLayerHostingView. 2- add the following line to the app delegate didFinishLaunchingWithOptions

[detailViewController performSelector:@selector(configureView) withObject:nil afterDelay:0];

3- add the following to DetailViewController configureView

CGRect graphFrame = CGRectMake(0, 43, 662, 450); GraphController *graphController = [[[GraphController alloc] initWithNibName:@"GraphController" bundle:nil] autorelease]; [graphController.view setFrame:graphFrame]; [self.view addSubview:graphController.view]; [graphController reloadData];

4- the reloadData method in GraphController is pretty much pasted from one of the CorePlot samples (DatePlot) and I will copy and paste (most of) it here-

-(void)reloadData { if (!graph) { [self parentViewController]; [self.view addSubview:layerHost];

// Create graph from theme graph = [[CPXYGraph alloc] initWithFrame:CGRectZero]; CPTheme *theme = [CPTheme themeNamed:@"Dark Gradients"]; [graph applyTheme:theme]; .... [layerHost setHostedLayer: graph]; .... // Setup scatter plot space CPXYPlotSpace *plotSpace = (CPXYPlotSpace *)graph.defaultPlotSpace; NSTimeInterval xLow = 0.0f; plotSpace.xRange = [CPPlotRange plotRangeWithLocation:CPDecimalFromFloat(xLow) length:CPDecimalFromFloat(oneDay*5.0f)]; plotSpace.yRange = [CPPlotRange plotRangeWithLocation:CPDecimalFromFloat(1.0) length:CPDecimalFromFloat(3.0)];

// Axes CPXYAxisSet *axisSet = (CPXYAxisSet *)graph.axisSet; CPXYAxis *x = axisSet.xAxis; x.majorIntervalLength = CPDecimalFromFloat(oneDay); x.orthogonalCoordinateDecimal = CPDecimalFromString(@"2"); x.minorTicksPerInterval = 0; NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease]; dateFormatter.dateStyle = kCFDateFormatterShortStyle; CPTimeFormatter *timeFormatter = [[[CPTimeFormatter alloc] initWithDateFormatter:dateFormatter] autorelease]; timeFormatter.referenceDate = refDate; x.labelFormatter = timeFormatter;

CPXYAxis *y = axisSet.yAxis; y.majorIntervalLength = CPDecimalFromString(@"0.5"); y.minorTicksPerInterval = 5; y.orthogonalCoordinateDecimal = CPDecimalFromFloat(oneDay);

// Create a plot that uses the data source method CPScatterPlot *dataSourceLinePlot = [[[CPScatterPlot alloc] init] autorelease]; dataSourceLinePlot.identifier = @"Date Plot"; dataSourceLinePlot.dataLineStyle.lineWidth = 3.f; dataSourceLinePlot.dataLineStyle.lineColor = [CPColor greenColor]; dataSourceLinePlot.dataSource = self; [graph addPlot:dataSourceLinePlot];

// Add some data NSMutableArray *newData = [NSMutableArray array]; NSUInteger i; for ( i = 0; i < 5; i++ ) { NSTimeInterval x = oneDay*i; id y = [NSDecimalNumber numberWithFloat:1.2*rand()/(float)RAND_MAX + 1.2]; [newData addObject: [NSDictionary dictionaryWithObjectsAndKeys: [NSDecimalNumber numberWithFloat:x], [NSNumber numberWithInt:CPScatterPlotFieldX], y, [NSNumber numberWithInt:CPScatterPlotFieldY], nil]]; } plotData = newData; } }

The offending line is [graph addPlot:dataSourceLinePlot]; If I comment this out the simulator comes up and displays the x and y axis of the graph and of course no data. Adding this line back causes the following SIGART-

2010-09-15 14:35:58.959 SplitViewWithCorePlot[17301:207] relabel < bounds: {{0, 0}, {558, 386}}> Program received signal: “EXC_BAD_ACCESS”.

Can anyone help?

Answer 1

It doesn't look like you're retaining the data array anywhere. Try changing the last statement to

plotData = [newData retain];

or, if you have a property defined for it,

self.plotData = newData;

Eric