Line Chart

Description: creating of a line chart that uses the specified data source.

The ViewController.h File

#import <Charting/ChartTouchesDelegate.h>
#import <Charting/Chart.h>
#import <Charting/LineSeries.h>
@interface ViewController : UIViewController<ChartTouchesDelegate>
{
    Chart *chart;
    float max;
    float min;
    LineSeries *currSeries;
    NSMutableDictionary *m_numberFormat;
}
- (void) executeExample;
- (ChartLabel *)createDefaultLabel;
@end

The ViewController.m File

#import "ViewController.h"
#import "DataSource.h"
#import "TimeIndexDelegate.h"
#import "LevelLineHolderDelegate.h"
@implementation ViewController
- (void)viewDidLoad
{
    [super viewDidLoad];
    // Determine link to selected series
    currSeries = nil;
    
    m_numberFormat = [[NSMutableDictionary dictionaryWithObjectsAndKeys:
                       [NSNumber numberWithBool:NO], @"asInSource",
                       [NSNumber numberWithInt:2], @"decNumbers",
                       [NSNumber numberWithBool:YES], @"separator",
                       @"", @"prefix",
                       @"", @"prefix",
                       [NSNumber numberWithBool:NO], @"negativeRed",
                       nil] retain];
    // Create a chart and determine its size
    chart = [[Chart alloc] initWithName:@"chart"];
    chart.frame = CGRectMake(0, 0, 600, 550);
    chart.backgroundColor = [UIColor whiteColor];
    ValueAxis *ax = [chart.axes objectForKey:[NSNumber numberWithInt:AxisLineX]];
    ax.axisLabelsVertical = NO;
    // Create a data source
    DataSource *datasource = [[DataSource alloc] init];
    // Create line chart series
    // Create the first series
    LineSeries *series = [LineSeries new];
    series.dataIndex = 0; // Series index, numbering starts from zero
    series.defaultLabel = [self createDefaultLabel];
    [series setColor:[UIColor blueColor]]; // Series line color
    series.isLegendVisible = YES; // Display in legend
    [series setShadowColor:[UIColor blueColor]]; // Shadow color
    series.shadowOpacity = 0.2;// Shadow transparency
    series.shadowRadius = 0.01;// Shadow radius
    series.showShadow = YES; // Display shadow
    // Create the second series
    LineSeries *series1 = [LineSeries new];
    series1.dataIndex = 1;
    series1.defaultLabel = [self createDefaultLabel];
    [series1 setColor:[UIColor redColor]];
    series1.isLegendVisible = YES;
    [series1 setShadowColor:[UIColor redColor]];
    series1.shadowOpacity = 0.2;
    series1.shadowRadius = 0.01;
    series1.showShadow = YES;
    // Create the third series
    LineSeries *series2 = [LineSeries new];
    series2.dataIndex = 2;
    series2.defaultLabel = [self createDefaultLabel];
    [series2 setColor:[UIColor greenColor]];
    series2.isLegendVisible = YES;
    [series2 setShadowColor:[UIColor greenColor]];
    series2.shadowOpacity = 0.2;
    series2.shadowRadius = 0.01;
    series2.showShadow = YES;
    // Create the fourth series
    LineSeries *series3 = [LineSeries new];
    series3.dataIndex = 3;
    series3.defaultLabel = [self createDefaultLabel];
    [series3 setColor:[UIColor darkGrayColor]];
    series3.isLegendVisible = YES;
    [series3 setShadowColor:[UIColor darkGrayColor]];
    series3.shadowOpacity = 0.2;
    series3.shadowRadius = 0.01;
    series3.showShadow = YES;
    // Set data source
    [chart setDataSource:datasource];
    [chart setDelegate:self];
    // Get maximum and minimum scale values of Y axis
    [datasource prepare];
    // Add created series to chart
    [chart addSeries:series];
    [chart addSeries:series1];
    [chart addSeries:series2];
    [chart addSeries:series3];
    // Refresh data
    [chart forceDataUpdate];
    // Execute custom example
    [self executeExample];
    // Display chart
    [self.view addSubview:chart];
    // Calculate size for chart drawing
    min = datasource.yMin;
    max = datasource.yMax;
}
// Function for example execution
-(void) executeExample{
};
// Create point labels
- (ChartLabel *)createDefaultLabel
{
    ChartLabel *result = [[[ChartLabel alloc] initWithFrame:CGRectZero] autorelease];
    result.background = [[SolidColorBrush new] autorelease]; // Background
    result.borderColor = [UIColor blackColor]; // Border color
    result.borderThickness = 1; // Border thickness
    result.borderRadius = 10; // Angle rounding radius
    result.font = [UIFont fontWithName:@"Arial" size:18]; // Font
    result.formatter = [NSNumberFormatter new];
    result.textAlignment = AlignmentCenter; // Text alignment
    result.textColor = [UIColor blackColor]; // Text color
    // Determine text formatting mask
    result.mask = [NSString stringWithFormat:@"%@#FVAL%@",
                   (NSString *)[m_numberFormat objectForKey:@"prefix"],
                   (NSString *)[m_numberFormat objectForKey:@"suffix"]];
    result.countOfDecimalNumbers = 3; // Number of displayed decimal places
    result.displayNegativesInRed = NO; // Negative value display format
    // Hide additional lines
    result.hasHorizontalNoteLine = result.hasVerticalNoteLine = result.hasFootNoteLine = NO;
    // Set minimum width
    result.minWidth = 0;
    return result;
}
@end

See also:

Creating a Line Chart