This code:

- (void)viewDidLoad
{
	EFCalendarGraph *calendarGraph = [[EFCalendarGraph alloc] initWithEndDate:[NSDate new]];
	self.calendarGraph.dataSource = self;
	[self.view addSubview:calendarGraph];
	self.calendarGraph.frame = CGRectMake(20, CGRectGetHeight(self.view.bounds)/2 - 60, CGRectGetWidth(self.view.bounds) - 40, 120);
	
	[self.calendarGraph reloadData];
}

- (NSUInteger)numberOfDataPointsInCalendarGraph:(EFCalendarGraph *)calendarGraph
{
    return 14;
}

-(id)calendarGraph:(EFCalendarGraph *)calendarGraph
      valueForDate:(NSDate *)date
daysAfterStartDate:(NSUInteger)daysAfterStartDate
 daysBeforeEndDate:(NSUInteger)daysBeforeEndDate
{
    return arc4random() % 2 == 0 ? @0 : @(arc4random() % 5;
}

will produce this:

or with 365 days:

Also, note that I am uploading this on a Monday. Since we are setting this up with an end date initWithEndDate..., you'll see the last box is the second from the top. The days start with Sunday at the top and each day follows normally. This will be configurable in the future.

Until the first CocoaPods release, clone the project and copy the EFCalendarGraph/NSDate+Utilities.{h,m} files into your project.

It's important to note that after changing any of the options or your data, you should call [calendarGraph reloadData].

The EFCalendarGraphDataSource protocol defines 2 required methods that allow it to present your data:

- (NSUInteger)numberOfDataPointsInCalendarGraph:(EFCalendarGraph *)calendarGraph

This is very self explanatory, just return the number of squares that you want to show. This is important because it is how the view decides how big the boxes can be and still fit inside its bounds.

- (id)calendarGraph:(EFCalendarGraph *)calendarGraph
       valueForDate:(NSDate *)date
 daysAfterStartDate:(NSUInteger)daysAfterStartDate
  daysBeforeEndDate:(NSUInteger)daysBeforeEndDate;

This is the method where you will return the data points for each square when requested. The return type says id, but is currently only accepting NSNumber. In the future, I would like to support accepting any id and optinally delegating to the user to determine the denomination.

###Properties (default)

####EFCalendarGraphSquareModifier squareModifier (EFCalendarGraphSquareModifierAlpha)

Currently the only value, setting this to EFCalendarGraphSquareModifierAlpha will cause variance in value to change the alpha of each of the boxes.

####NSArray *modifierDenominations (@[@.3, @.4, @.5, @.6, @.7, @.9])

Seemingly random, but this set of numbers seems to work fairly well for most data sets that I've encountered so far. You can set this array to any set of numbers between 0 and 1. It does not have to be 6 numbers either, you can have as many or as few as you want.

####UIColor *baseColor ([UIColor greenColor])

This is the color that will fill the squares.

####UIColor *zeroColor ([UIColor colorWithRed:.9 green:.9 blue:.9 alpha:.5])

This is the color that the boxes will be when the value for the box is 0.

Copyright (c) 2015 Eliot Fowler

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