Scatterplot Not Showing - ios6

Question

I'm doing an application that requires core plot for drawing charts, I'm new to this library and I am finding it pretty hard to find good documentation or examples. I'm running into a problem where the line for the graph is not being display despite the fact that the data source method is getting called and returning the right number at the right index. Also the x Axis is being displayed wrong (Check the image below(1.0)). The Y axis is set correctly and the increment is also correct. I've been playing around trying to figure out what it's wrong but I spent too much time already so I was hoping to find some one here that could help or point me at the right direction. This is my implementation file :
-(void)initPlot {
[self generateData];
[self configureHost];
[self configureGraph];
[self configurePlots];
[self configureAxes];
}
- (void)generateData{
//Array containing all the dates that will be displayed on the X axis
dates = [NSArray arrayWithObjects:#"Apr 25", #"Apr 26", #"Apr 29",#"Apr 30", #"May 1", nil];
//Dictionary containing the name of the single set and its associated color
sets = [NSDictionary dictionaryWithObjectsAndKeys:[UIColor redColor], #"Plot 1",nil];
_dataY = [[NSMutableArray alloc] init];
[_dataY insertObject:[NSNumber numberWithFloat:618.0] atIndex:0];
[_dataY insertObject:[NSNumber numberWithFloat:613.0] atIndex:0];
[_dataY insertObject:[NSNumber numberWithFloat:613.0] atIndex:0];
[_dataY insertObject:[NSNumber numberWithFloat:614.0] atIndex:0];
[_dataY insertObject:[NSNumber numberWithFloat:604.0] atIndex:0];
_dataForPlot = [[NSMutableArray alloc] init];
for(int i = 0; i < dates.count; i++){
NSString *date = [dates objectAtIndex:i];
NSNumber *price = [_dataY objectAtIndex:i];
NSMutableDictionary *point1 = [[[NSMutableDictionary alloc] initWithObjectsAndKeys:date, #"x", price, #"y", nil] autorelease];
[_dataForPlot addObject:point1];
}
NSLog(#"Data %#",_dataForPlot);
}
-(void)configureHost {
_hostView.allowPinchScaling = NO;
}
-(void)configureGraph {
graph = [[CPTXYGraph alloc] initWithFrame:CGRectZero];
[graph applyTheme:[CPTTheme themeNamed:kCPTPlainBlackTheme]];
_hostView.hostedGraph = graph;
graph.plotAreaFrame.masksToBorder = NO;
// Configure the Graph Padding
graph.paddingLeft = 0.0f;
graph.paddingTop = 0.0f;
graph.paddingRight = 0.0f;
graph.paddingBottom = 0.0f;
CPTMutableLineStyle *borderLineStyle = [CPTMutableLineStyle lineStyle];
borderLineStyle.lineColor = [CPTColor whiteColor];
borderLineStyle.lineWidth = 2.0f;
graph.plotAreaFrame.borderLineStyle = borderLineStyle;
graph.plotAreaFrame.paddingTop = 10.0;
graph.plotAreaFrame.paddingRight = 10.0;
graph.plotAreaFrame.paddingBottom = 40.0;
graph.plotAreaFrame.paddingLeft = 70.0;
// Set graph title
graph.title = #"Test";
// Create and set text style
CPTMutableTextStyle *titleStyle = [CPTMutableTextStyle textStyle];
titleStyle.color = [CPTColor whiteColor];
titleStyle.fontName = #"Helvetica-Bold";
titleStyle.fontSize = 16.0f;
graph.titleTextStyle = titleStyle;
graph.titlePlotAreaFrameAnchor = CPTRectAnchorTop;
graph.titleDisplacement = CGPointMake(0.0f, 10.0f);
graph.plotAreaFrame.borderLineStyle = nil;
}
- (void)configurePlots{
CPTColor *aColor = [CPTColor redColor];
CPTMutableLineStyle *barLineStyle = [[[CPTMutableLineStyle alloc] init] autorelease];
barLineStyle.lineWidth = 1.0;
barLineStyle.lineColor = [CPTColor whiteColor];
CPTMutableTextStyle *whiteTextStyle = [CPTMutableTextStyle textStyle];
whiteTextStyle.color = [CPTColor whiteColor];
// Enable user interactions for plot space
CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *) graph.defaultPlotSpace;
plotSpace.allowsUserInteraction = YES;
plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(0.0) length:CPTDecimalFromFloat(5.0)];
plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat([self lowerValue]) length:CPTDecimalFromFloat([self higherValue])];
dataSourceLinePlot = [[[CPTScatterPlot alloc] init] autorelease];
dataSourceLinePlot.identifier = #"Plot 1";
dataSourceLinePlot.dataSource = self;
[graph addPlot:dataSourceLinePlot];
CPTGradient *areaGradient = [CPTGradient gradientWithBeginningColor :[CPTColor greenColor]
endingColor :[CPTColor blackColor]];
areaGradient.angle = -90.0f ;
CPTFill *areaGradientFill = [ CPTFill fillWithGradient :areaGradient];
dataSourceLinePlot.areaFill = areaGradientFill;
dataSourceLinePlot.areaBaseValue = CPTDecimalFromString (#"0.0");
dataSourceLinePlot.interpolation = CPTScatterPlotInterpolationLinear;
// Set up plot space
[plotSpace scaleToFitPlots:[NSArray arrayWithObjects:dataSourceLinePlot, nil]];
CPTMutablePlotRange *xRange = [plotSpace.xRange mutableCopy];
[xRange expandRangeByFactor:CPTDecimalFromCGFloat(1.1f)];
plotSpace.xRange = xRange;
CPTMutablePlotRange *yRange = [plotSpace.yRange mutableCopy];
[yRange expandRangeByFactor:CPTDecimalFromCGFloat(1.4f)];
plotSpace.yRange = yRange;
// Create styles and symbols
CPTMutableLineStyle *aLineStyle = [[dataSourceLinePlot.dataLineStyle mutableCopy] autorelease];
aLineStyle.lineWidth = 1.0;
aLineStyle.lineColor = aColor;
dataSourceLinePlot.dataLineStyle = aLineStyle;
//Add legend
CPTLegend *theLegend = [CPTLegend legendWithGraph:graph];
theLegend.numberOfRows = sets.count;
theLegend.fill = [CPTFill fillWithColor:[CPTColor colorWithGenericGray:0.15]];
theLegend.borderLineStyle = barLineStyle;
theLegend.cornerRadius = 10.0;
theLegend.swatchSize = CGSizeMake(15.0, 15.0);
whiteTextStyle.fontSize = 13.0;
theLegend.textStyle = whiteTextStyle;
theLegend.rowMargin = 5.0;
theLegend.paddingLeft = 10.0;
theLegend.paddingTop = 10.0;
theLegend.paddingRight = 10.0;
theLegend.paddingBottom = 10.0;
graph.legend = theLegend;
graph.legendAnchor = CPTRectAnchorTopLeft;
graph.legendDisplacement = CGPointMake(80.0, -10.0);
}
- (void)configureAxes{
CPTMutableTextStyle *axisTextStyle = [[CPTMutableTextStyle alloc] init];
axisTextStyle.color = [CPTColor whiteColor];
axisTextStyle.fontName = #"Helvetica-Bold";
axisTextStyle.fontSize = 11.0f;
// Grid line styles
CPTMutableLineStyle *majorGridLineStyle = [CPTMutableLineStyle lineStyle];
majorGridLineStyle.lineWidth = 0.75;
majorGridLineStyle.lineColor = [[CPTColor whiteColor] colorWithAlphaComponent:0.1];
CPTMutableLineStyle *minorGridLineStyle = [CPTMutableLineStyle lineStyle];
minorGridLineStyle.lineWidth = 0.25;
minorGridLineStyle.lineColor = [[CPTColor whiteColor] colorWithAlphaComponent:0.1];
// Line Style
CPTMutableLineStyle *lineStyle = [CPTMutableLineStyle lineStyle];
lineStyle.lineColor = [CPTColor whiteColor];
lineStyle.lineWidth = 2.0f;
CPTMutableLineStyle *axisLineStyle = [CPTMutableLineStyle lineStyle];
axisLineStyle.lineWidth = 2.0f;
axisLineStyle.lineColor = [CPTColor whiteColor];
//Axises
CPTXYAxisSet *axisSet = (CPTXYAxisSet *)graph.axisSet;
//Y axis
CPTXYAxis *y = axisSet.yAxis;
y.title = #"Price";
y.titleOffset = 50.0f;
y.labelingPolicy = CPTAxisLabelingPolicyAutomatic;
y.majorGridLineStyle = majorGridLineStyle;
y.minorGridLineStyle = minorGridLineStyle;
y.axisConstraints = [CPTConstraints constraintWithLowerOffset:0.0];
y. majorIntervalLength = CPTDecimalFromString(#"5");
y.minorTicksPerInterval = 4;
y.orthogonalCoordinateDecimal = CPTDecimalFromString(#"0");
y.minorTickLineStyle = nil;
y.labelOffset = 2.0f;
// Configure x-axis
CPTXYAxis *x = axisSet.xAxis;
x. majorIntervalLength = CPTDecimalFromString (#"5");
x.orthogonalCoordinateDecimal = CPTDecimalFromInt(0);
x.majorIntervalLength = CPTDecimalFromInt(5);
x.minorTicksPerInterval = 0;
x.labelingPolicy = CPTAxisLabelingPolicyNone;
x.majorGridLineStyle = majorGridLineStyle;
x.axisConstraints = [CPTConstraints constraintWithLowerOffset:0.0];
NSMutableArray *customLabels = [NSMutableArray arrayWithCapacity:[_dataForPlot count]];
static CPTMutableTextStyle *labelTextStyle = nil;
labelTextStyle = [[CPTMutableTextStyle alloc] init];
labelTextStyle.color = [CPTColor whiteColor];
labelTextStyle.fontSize = 10.0f;
int index = 0;
for(NSString *date in dates){
CPTAxisLabel *newLabel = [[CPTAxisLabel alloc] initWithText:date textStyle:labelTextStyle];
newLabel.tickLocation = CPTDecimalFromInt(index);
newLabel.offset = x.labelOffset + x.majorTickLength + 5;
newLabel.rotation = M_PI / 4;
[customLabels addObject:newLabel];
[newLabel release];
index++;
}
x.axisLabels = [NSSet setWithArray:customLabels];
}
- (float)higherValue{
NSNumber* max = [_dataY valueForKeyPath:#"#max.self"];
return [max floatValue];
}
- (float)lowerValue{
NSNumber* min = [_dataY valueForKeyPath:#"#min.self"];
return [min floatValue];
}
The Data Source Methods :
-(NSUInteger)numberOfRecordsForPlot:(CPTPlot *)plot {
return dates.count;
}
-(NSNumber *)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index {
NSString *key = (fieldEnum == CPTScatterPlotFieldX ? #"x" : #"y");
NSNumber *num = 0;
//if ( [(NSString *)plot.identifier isEqualToString:#"Plot 1"] ) {
num = [[_dataForPlot objectAtIndex:index] valueForKey:key];
if ( fieldEnum == CPTScatterPlotFieldX ) {
num = 0;
}
//}
CABasicAnimation *fadeInAnimation = [CABasicAnimation animationWithKeyPath:#"opacity"];
fadeInAnimation.duration = 1.0f;
fadeInAnimation.removedOnCompletion = NO;
fadeInAnimation.fillMode = kCAFillModeForwards;
fadeInAnimation.toValue = [NSNumber numberWithFloat:2.0];
[dataSourceLinePlot addAnimation:fadeInAnimation forKey:#"animateOpacity"];
NSLog(#"NUM : %# for key : %# at index : %i",num,key,index);
return num;
}
This is the image :

Answer 1

The x-axis is displayed exactly as you told it. It ranges between -0.25 and 5.25 (0 to 5 expanded by 10%) with five labels at 0, 1, 2, 3, and 4.
The datasource returns nil (0) for the CPTScatterPlotFieldX field for every point. This tells the plot to ignore that point. Based on the plot place range you've set up, you should return an NSNumber containing the index for that field.