Core plot - pie chart not showing enough segments

In numberOfRecordsForPlot:... I have this code:

int count = [[optsDict objectForKey:@"Values"] count];
NSLog(@"pie count: %i", count);
return count;

It outputs pie count: 4 thus (unless I'm misinterpreting) there should be 4 segments to the pie chart.

开发者_运维百科

Then in numberForPlot:(CPPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index I have this:

double percentage = ((float)counter/(float)total)*100;
num = (NSDecimalNumber *)[NSDecimalNumber numberWithInt:(int)percentage];

NSLog(@"index: %i, percentage: %f", index, percentage);
NSLog(@"%@", num);

return num;

This outputs:

index: 0, percentage: 9.090909
9
index: 1, percentage: 9.090909
9
index: 2, percentage: 63.636364
63
index: 3, percentage: 18.181818
18

So I am assuming (reasonably) that the function is getting run once for each segment and its returning a figure for all of them!

However the chart looks like this:

Theres not really much else I can tell you. Thats all I know, I don't know much about core plot!

If there is ANY help you can give me I'd be very appreciative!

Thank you

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I play with your values and I think I found the problem in your code.

Try to return in -(NSNumber *)numberForPlot:(CPPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index object of class NSNumber

num = (NSNumber *)[NSNumber numberWithInt:(int)percentage];
return num;

I was testing this in sample that is included in CorePlot framework. Firstly I tried to init contentArray array with NSNumbers:

NSMutableArray *contentArray = [NSMutableArray arrayWithObjects:[NSNumber numberWithInt:9.0909099], [NSNumber numberWithInt:9.0909099], [NSNumber numberWithInt:63.63636463], [NSNumber numberWithInt:18.181818], nil];

And everything works perfect. Then I've tried to init array as in your code with NSDecimalNumbers:

NSMutableArray *contentArray = [NSMutableArray arrayWithObjects:[NSDecimalNumber numberWithInt:9.0909099], [NSDecimalNumber numberWithInt:9.0909099], [NSDecimalNumber numberWithInt:63.63636463], [NSDecimalNumber numberWithInt:18.181818], nil];

And I've received exactly your double colored chart.

Hope this will help you =)

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Do you implement

- (CPTFill *)sliceFillForPieChart:(CPTPieChart *)pieChart recordIndex:(NSUInteger)index

which is in the CPTPieChartDataSource protocol? Since there are no borderlines between sections, it might be drawing several with the same color. Make sure you're returning a different color CPTFill for each index.

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Thomas i have done this pia chart using titanium framework.You have to use java script for display pia chart

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It looks like you missed first and second slices. numberOfRecordsForPlot can return 4, but in numberForPlot some code returns nil.. I created a new Pie Chart with your values, and all works nice. See code below.

You can also try to see data labels for every slice in the -(CPLayer *)dataLabelForPlot:(CPPlot *)plot recordIndex:(NSUInteger)index delegate method. If you really have 4 slices then 2 of them will placed at the same position. Code below is as well.

-(void) viewDidLoad{
    NSMutableArray *contentArray = [NSMutableArray arrayWithObjects:[NSNumber numberWithInt:9], [NSNumber numberWithInt:9], [NSNumber numberWithInt:63], [NSNumber numberWithInt:18], nil];
    self.dataForChart = contentArray;

    // Add pie chart
    CPPieChart *piePlot = [[CPPieChart alloc] init];
    piePlot.dataSource = self;
    piePlot.pieRadius = 100.0;
    piePlot.identifier = @"Pie Chart 1";
    piePlot.startAngle = M_PI;
    piePlot.sliceDirection = CPPieDirectionClockwise;
    piePlot.delegate = self;
    [pieChart addPlot:piePlot];
    [piePlot release];
}

#pragma mark -
#pragma mark Plot Data Source Methods
-(NSUInteger)numberOfRecordsForPlot:(CPPlot *)plot{
    return [self.dataForChart count];
}

-(NSNumber *)numberForPlot:(CPPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index {
    if ( index >= [self.dataForChart count] ) return nil;

    if ( fieldEnum == CPPieChartFieldSliceWidth ) {
        return [self.dataForChart objectAtIndex:index];
    }
    else {
        return [NSNumber numberWithInt:index];
    }
}

-(CPLayer *)dataLabelForPlot:(CPPlot *)plot recordIndex:(NSUInteger)index {
    CPTextLayer *label = [[CPTextLayer alloc] initWithText:[NSString stringWithFormat:@"%lu", index]];
    label.textStyle.color = [CPColor lightGrayColor];
    return [label autorelease];
}