LFLineChartView 0.1.1

Maintained by Unclaimed.

You want to add pod 'LFLineChartView', '~> 0.1' similar to the following to your Podfile:

target 'MyApp' do
  pod 'LFLineChartView', '~> 0.1'
end

Then run a pod install inside your terminal, or from CocoaPods.app.

Alternatively to give it a test run, run the command:

pod try LFLineChartView

LFLineChartView 0.1.1

By
leonardfactory

A view to show scrollable, highly customizable line charts with parallax effect on iOS.

Requirements

Xcode 5 (or higher)
Apple LLVM compiler
ARC
iOS 6.0 (or higher)

Demo

Build and run LFLineChartViewExample project, available in the Example/Storyboard/ folder.

Installation

Recommended way to install LFLineChartView is via CocoaPods. Add the following line to your Podfile:

pod 'LFLineChartView', '~> 0.1'

Install it:

$ pod install

Then open your workspace.

Usage

To use LFLineChartView you need to inherit from LFLineChartView. This component uses datasource & delegate approach to provide content, so you need to implement those two protocols, even in the same inherited class.

@interface LFExampleLineChartView : LFLineChartView <LFLineChartViewDataSource, LFLineChartViewDelegate>

@end

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self)
    {
        self.datasource      = self;
        self.chartDelegate   = self;

        // …
    }
    return self;
}

Datasource

Datasource provides content for the chart. Currently, only one set of points is supported.

Lines and dots are rendered using CAShapeLayer instances. You can customize them as you want in the createLayerAtIndex: and createLineLayerBetweenIndex:andIndex: methods, as shown in the example project.

Vertical position (y-axis) is calculated dynamically between maximum and minimum value for yAtIndex: for each index. The same happens for size (circle radius) for dots CAShapeLayer, using sizeAtIndex:.

You can draw horizontal lines across the chart using createMiddleLineLayerAtIndex: and related methods. yForMiddleLineAtIndex: use the same value scale of yAtIndex:, so displayed height is automagically calculated.

@protocol LFLineChartViewDataSource <NSObject>

- (NSUInteger) numberOfItemsInLineChartView:(LFLineChartView *)lineChartView;
- (CAShapeLayer *) lineChartView:(LFLineChartView *)lineChartView createLayerAtIndex:(NSUInteger) index;
- (CAShapeLayer *) lineChartView:(LFLineChartView *)lineChartView createLineLayerBetweenIndex:(NSUInteger) firstIndex andIndex:(NSUInteger) secondIndex;

- (CGFloat) yAtIndex:(NSUInteger) index;

@optional
// Size
- (CGFloat) sizeAtIndex:(NSUInteger) index;

// Text
- (NSString *) textAtIndex:(NSUInteger) index;
- (UIColor *) textColor;

// Lines
- (NSUInteger) numberOfMiddleLinesInLineChartView:(LFLineChartView *)lineChartView;
- (CAShapeLayer *) lineChartView:(LFLineChartView *)lineChartView createMiddleLineLayerAtIndex:(NSUInteger)index;
- (CGFloat) yForMiddleLineAtIndex:(NSUInteger) index;

// Empty view
- (UIView *) emptyViewForLineChartView:(LFLineChartView *)lineChartView;

@end

Delegate

Delegate handles events from the chart. Currently, only touch on items is supported.

@protocol LFLineChartViewDelegate <NSObject>

@optional
- (void) lineChartView:(LFLineChartView *)lineChartView didPressLayerAtIndex:(NSUInteger) index;

@end

Customization

More options are available to customize LFLineChartView. You can set those directly in the init/initWithFrame/initWithCoder/etc. method where you instantiate the inherited class.

@property (assign) CGFloat bounceTolerance;
@property (assign) CGFloat horizontalPadding;
@property (assign) CGFloat verticalPadding;
@property (assign) CGFloat itemSpacing;
@property (assign) CGFloat initialScale;

@property (assign) CGFloat minimumItemRadius;
@property (assign) CGFloat maximumItemRadius;

@property (assign) CGFloat minimumTextHeight;
@property (assign) CGFloat textHeight;
@property (assign) CGFloat textWidth;

You can find more information on how to implement those methods in the example.

Todo

Support multiple set of points
Write new examples and a better doc
Do not use a UIScrollView?

Contact

Leonardo Ascione

License

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.