iOS
Grafiek (Coreplot)
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Grafieken maken met CorePlot
Core Plot biedt een podspec, dus je kunt cocoapods gebruiken als je bibliotheekbeheerder, wat het installeren en bijwerken veel eenvoudiger zou moeten maken
Installeer cocoapods op uw systeem
Voeg in de projectmap een tekstbestand toe aan uw project met de naam Podfile door pod init
in uw projectmap te typen
Voeg in de Podfile de regelpod 'CorePlot', '~> 1.6' toe
In de terminal, cd naar je projectmap en voer podinstallatie uit
Cocoapods genereert een xcworkspace-bestand, dat u moet gebruiken voor het starten van uw project (het .xcodeproj-bestand bevat geen podbibliotheken)
Open de .xcworkspace gegenereerd door CocoaPods
In het ViewController.h-bestand
#import <CorePlot/ios/CorePlot.h>
//#import "CorePlot-CocoaTouch.h" or the above import statement
@interface ViewController : UIViewController<CPTPlotDataSource>
In het ViewController.m-bestand
-(void)loadView
{
[super loadView];
// We need a hostview, you can create one in IB (and create an outlet) or just do this:
CPTGraphHostingView* hostView = [[CPTGraphHostingView alloc] initWithFrame:CGRectMake(10, 40, 300, 400)];
hostView.backgroundColor=[UIColor whiteColor];
self.view.backgroundColor=[UIColor blackColor];
[self.view addSubview: hostView];
// Create a CPTGraph object and add to hostView
CPTGraph* graph = [[CPTXYGraph alloc] initWithFrame:CGRectMake(10, 40, 300, 400)];
hostView.hostedGraph = graph;
// Get the (default) plotspace from the graph so we can set its x/y ranges
CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *) graph.defaultPlotSpace;
// Note that these CPTPlotRange are defined by START and LENGTH (not START and END) !!
[plotSpace setYRange: [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat( 0 ) length:CPTDecimalFromFloat( 20 )]];
[plotSpace setXRange: [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat( -4 ) length:CPTDecimalFromFloat( 8 )]];
// Create the plot (we do not define actual x/y values yet, these will be supplied by the datasource...)
CPTScatterPlot* plot = [[CPTScatterPlot alloc] initWithFrame:CGRectZero];
// Let's keep it simple and let this class act as datasource (therefore we implemtn <CPTPlotDataSource>)
plot.dataSource = self;
// Finally, add the created plot to the default plot space of the CPTGraph object we created before
[graph addPlot:plot toPlotSpace:graph.defaultPlotSpace];
}
// This method is here because this class also functions as datasource for our graph
// Therefore this class implements the CPTPlotDataSource protocol
-(NSUInteger)numberOfRecordsForPlot:(CPTPlot *)plotnumberOfRecords
{
return 9; // Our sample graph contains 9 'points'
}
// This method is here because this class also functions as datasource for our graph
// Therefore this class implements the CPTPlotDataSource protocol
-(NSNumber *)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index
{
// We need to provide an X or Y (this method will be called for each) value for every index
int x = index - 4;
// This method is actually called twice per point in the plot, one for the X and one for the Y value
if(fieldEnum == CPTScatterPlotFieldX)
{
// Return x value, which will, depending on index, be between -4 to 4
return [NSNumber numberWithInt: x];
} else
{
// Return y value, for this example we'll be plotting y = x * x
return [NSNumber numberWithInt: x * x];
}
}
De gegenereerde output is zoals hieronder aangegeven: