coreplot pie chart example - core-plot

Question

I am trying to follow the tutorial at http://www.raywenderlich.com/13269/how-to-draw-graphs-with-core-plot-part-1
I am working on ios 7 and latest core chart library (1.3)
I am trying to draw a pie chart. My example compiles fine, I get the title header but I do not get any pie chart drawn. What I see is shown below:
My main source code that contains the logic is given below. Kindly help
//
// CPDFirstViewController.m
// CorePlotDemo
//
// Created by R Menon on 9/19/13.
// Copyright (c) 2013 4stepfinance Inc. All rights reserved.
//
#import "CPDPieChartViewController.h"
#interface CPDPieChartViewController ()
#property (weak, nonatomic) IBOutlet UIToolbar *toolbar;
#property (weak, nonatomic) IBOutlet UIBarButtonItem *themeButton;
#property (strong, nonatomic) CPTGraphHostingView *hostView;
#property (strong, nonatomic) CPTTheme *selectedTheme;
- (void)initPlot;
-(void)configureHost;
-(void)configureGraph;
-(void)configureChart;
-(void)configureLegend;
#end
#implementation CPDPieChartViewController
#pragma mark - Chart behavior
- (void)initPlot {
[self configureHost];
[self configureChart];
[self configureGraph];
[self configureLegend];
}
-(void)configureHost {
// Set up view frame
CGRect parentRect = self.view.bounds;
CGSize toolbarSize = self.toolbar.bounds.size;
parentRect = CGRectMake(parentRect.origin.x, (parentRect.origin.y + toolbarSize.height), parentRect.size.width, (parentRect.size.height - toolbarSize.height));
// Create host view
self.hostView = [(CPTGraphHostingView *) [CPTGraphHostingView alloc] initWithFrame:parentRect];
self.hostView.allowPinchScaling = NO;
[self.view addSubview:self.hostView];
}
-(void)configureGraph {
//Create and initialize graph
CPTGraph *graph = [[CPTXYGraph alloc] initWithFrame:self.hostView.bounds];
self.hostView.hostedGraph = graph;
graph.paddingLeft = 0.0f;
graph.paddingTop = 0.0f;
graph.paddingRight = 0.0f;
graph.paddingBottom = 0.0f;
graph.axisSet = nil;
// Set up text stile
CPTMutableTextStyle *textStyle = [CPTMutableTextStyle textStyle];
textStyle.color = [CPTColor grayColor];
textStyle.fontName = #"Helvetica-Bold";
textStyle.fontSize = 16.0f;
// Configure title
NSString *title = #"Portfolio Prices: May 1, 2012";
graph.title = title;
graph.titleTextStyle = textStyle;
graph.titlePlotAreaFrameAnchor = CPTRectAnchorTop;
graph.titleDisplacement = CGPointMake(0.0f, -12.0f);
// Set theme
self.selectedTheme = [CPTTheme themeNamed:kCPTPlainWhiteTheme];
[graph applyTheme:self.selectedTheme];
}
-(void)configureChart {
// 1 - Get reference to graph
CPTGraph *graph = self.hostView.hostedGraph;
// 2 - Create chart
CPTPieChart *pieChart = [[CPTPieChart alloc] init];
pieChart.dataSource = self;
pieChart.delegate = self;
pieChart.pieRadius = (self.hostView.bounds.size.height * 0.7) / 2;
pieChart.identifier = graph.title;
pieChart.startAngle = M_PI_4;
pieChart.sliceDirection = CPTPieDirectionClockwise;
// 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
[graph addPlot:pieChart];
}
-(void)configureLegend {
}
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:YES];
[self initPlot];
}
- (IBAction)themeTapped:(id)sender {
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#pragma mark - CPTPlotDataSource methods
- (NSUInteger)numberOfRecordsForPlot:(CPTPlot *)plot
{
return [[[CPDStockPriceStore sharedInstance] tickerSymbols] count];
}
- (NSNumber *)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)idx
{
if (CPTPieChartFieldSliceWidth == fieldEnum)
{
return [[[CPDStockPriceStore sharedInstance] dailyPortfolioPrices] objectAtIndex:idx];
}
return [NSDecimalNumber zero];
}
- (CPTLayer *)dataLabelForPlot:(CPTPlot *)plot recordIndex:(NSUInteger)idx {
static CPTMutableTextStyle *labelText = nil;
if (!labelText) {
labelText= [[CPTMutableTextStyle alloc] init];
labelText.color = [CPTColor grayColor];
}
// 2 - Calculate portfolio total value
NSDecimalNumber *portfolioSum = [NSDecimalNumber zero];
for (NSDecimalNumber *price in [[CPDStockPriceStore sharedInstance] dailyPortfolioPrices]) {
portfolioSum = [portfolioSum decimalNumberByAdding:price];
}
// 3 - Calculate percentage value
NSDecimalNumber *price = [[[CPDStockPriceStore sharedInstance] dailyPortfolioPrices] objectAtIndex:idx];
NSDecimalNumber *percent = [price decimalNumberByDividingBy:portfolioSum];
// 4 - Set up display label
NSString *labelValue = [NSString stringWithFormat:#"$%0.2f USD (%0.1f %%)", [price floatValue], ([percent floatValue] * 100.0f)];
// 5 - Create and return layer with label text
return [[CPTTextLayer alloc] initWithText:labelValue style:labelText];
}
-(NSString *)legendTitleForPieChart:(CPTPieChart *)pieChart recordIndex:(NSUInteger)index {
return #"";
}
#pragma mark - UIActionSheetDelegate methods
- (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex {
}
#end

Answer 1

Never mind. I had a typo:
Following method definition
- (void)initPlot {
[self configureHost];
[self configureChart];
[self configureGraph];
[self configureLegend];
}
should change to
- (void)initPlot {
[self configureHost];
[self configureGraph];
[self configureChart];
[self configureLegend];
}
In other words, I should invoke configureGraph before configureChart method.