/Scrollable-GraphView

An adaptive scrollable graph view for iOS to visualise simple discrete datasets. Written in Swift.

Primary LanguageSwiftMIT LicenseMIT

ScrollableGraphView

About

Example Application Usage

An adaptive scrollable graph view for iOS to visualise simple discrete datasets. Written in Swift. Originally written for a small personal project.

The main goal of the this graph component is to visualise simple discrete datasets and allow the the user to scroll through the graph.

Init Animation

Contents

Features

Feature List
Initialisation animations and range adaption animations.

Animating
Range adaption when scrolling through the graph. The range of the y-axis will automatically adapt to to the min and max of the visible points.

Adapting
Smooth scrolling around the graph.

Scrolling
Handles a relatively large number of points without lagging.

More_Scrolling
Many customisation options. (Check the customisation section)

Customising

Usage

Adding the ScrollableGraphView to your project:

Add the ScrollableGraphView class to your project. There are two ways to add the ScrollableGraphView to your project.

Manually

Add ScrollableGraphView.swift to your project in Xcode

CocoaPods

Add pod 'ScrollableGraphView' to your Podfile and then make sure to import ScrollableGraphView in your code.

Creating a graph and setting the data.

  1. Create a ScrollableGraphView instance and set the data and labels

    let graphView = ScrollableGraphView(frame: someFrame)
    let data: [Double] = [4, 8, 15, 16, 23, 42]
    let labels = ["one", "two", "three", "four", "five", "six"]
    graphView.setData(data, withLabels: labels)
  2. Add the ScrollableGraphView to the view hierarchy.

    someViewController.view.addSubview(graphView)

Things you could use it for:

  • ✔ Study applications to show time studied/etc
  • ✔ Weather applications
  • ✔ Prototyping
  • Simple data visualisation

Things you shouldn't/cannot use it for:

  • ✘ Rigorous statistical software
  • ✘ Important & complex data visualisation
  • ✘ Graphing continuous mathematical functions

Customisation

The graph can be customised by setting any of the following public properties before displaying the ScrollableGraphView. The defaults are shown below.

Line Styles

Property Description
lineWidth: CGFloat Specifies how thick the graph of the line is. In points.
lineColor: UIColor The color of the graph line. UIColor.
lineStyle: ScrollableGraphViewLineStyle Whether or not the line should be rendered using bezier curves are straight lines. Possible values:
  • ScrollableGraphViewLineStyle.Straight
  • ScrollableGraphViewLineStyle.Smooth
lineJoin How each segment in the line should connect. Takes any of the Core Animation LineJoin values.
lineCap The line caps. Takes any of the Core Animation LineCap values.

Fill Styles

Property Description
backgroundFillColor: UIColor The background colour for the entire graph view, not just the plotted graph.
shouldFill: Bool Specifies whether or not the plotted graph should be filled with a colour or gradient.
fillType: ScrollableGraphViewFillType Specifies whether to fill the graph with a solid colour or gradient. Possible values:
  • ScrollableGraphViewFillType.Solid
  • ScrollableGraphViewFillType.Gradient
fillColor: UIColor If fillType is set to .Solid then this colour will be used to fill the graph.
fillGradientStartColor: UIColor If fillType is set to .Gradient then this will be the starting colour for the gradient.
fillGradientEndColor: UIColor If fillType is set to .Gradient, then this will be the ending colour for the gradient.
fillGradientType:ScrollableGraphViewGradientType If fillType is set to .Gradient, then this defines whether the gradient is rendered as a linear gradient or radial gradient. Possible values:
  • ScrollableGraphViewFillType.Solid
  • ScrollableGraphViewFillType.Gradient

Bar Styles

Property Description
shouldDrawBarLayer: Bool Whether bars should be drawn or not. If you want a bar graph, this should be set to true. However, you will probably want to disable drawing the data points with shouldDrawDataPoint = false. If you want to hide the line as well: lineColor = UIColor.clearColor()
barWidth: CGFloat The width of an individual bar on the graph.
barColor: UIColor The actual colour of the bar.
barLineWidth: CGFloat The width of the outline of the bar
barLineColor: UIColor The colour of the bar outline

Spacing

spacing

Property Description
topMargin: CGFloat How far the "maximum" reference line is from the top of the view's frame. In points.
bottomMargin: CGFloat How far the "minimum" reference line is from the bottom of the view's frame. In points.
leftmostPointPadding: CGFloat How far the first point on the graph should be placed from the left hand side of the view.
rightmostPointPadding: CGFloat How far the final point on the graph should be placed from the right hand side of the view.
dataPointSpacing: CGFloat How much space should be between each data point.
direction: ScrollableGraphViewDirection Which way the user is expected to scroll from. Possible values:
  • ScrollableGraphViewDirection.LeftToRight
  • ScrollableGraphViewDirection.RightToLeft
For example, if it is set to .RightToLeft, the graph will start on the "right hand side" of the graph and the user will have to scroll towards the left.

Graph Range

Property Description
rangeMin: Double The minimum value for the y-axis. This is ignored when shouldAutomaticallyDetectRange or shouldAdaptRange = true
rangeMax: Double The maximum value for the y-axis. This is ignored when shouldAutomaticallyDetectRange or shouldAdaptRange = true
shouldAutomaticallyDetectRange: Bool If this is set to true, then the range will automatically be detected from the data the graph is given.
shouldRangeAlwaysStartAtZero: Bool Forces the graph's minimum to always be zero. Used in conjunction with shouldAutomaticallyDetectRange or shouldAdaptRange, if you want to force the minimum to stay at 0 rather than the detected minimum.

Data Point Drawing

Property Description
shouldDrawDataPoint: Bool Whether or not to draw a symbol for each data point.
dataPointType: ScrollableGraphViewDataPointType The shape to draw for each data point. Possible values:
  • ScrollableGraphViewDataPointType.Circle
  • ScrollableGraphViewDataPointType.Square
  • ScrollableGraphViewDataPointType.Custom
dataPointSize: CGFloat The size of the shape to draw for each data point.
dataPointFillColor: UIColor The colour with which to fill the shape.
customDataPointPath: ((centre: CGPoint) -> UIBezierPath)? If dataPointType is set to .Custom then you,can provide a closure to create any kind of shape you would like to be displayed instead of just a circle or square. The closure takes a CGPoint which is the centre of the shape and it should return a complete UIBezierPath.

Adapting & Animations

Property Description
shouldAdaptRange: Bool Whether or not the y-axis' range should adapt to the points that are visible on screen. This means if there are only 5 points visible on screen at any given time, the maximum on the y-axis will be the maximum of those 5 points. This is updated automatically as the user scrolls along the graph. Adapting
shouldAnimateOnAdapt: Bool If shouldAdaptRange is set to true then this specifies whether or not the points on the graph should animate to their new positions. Default is set to true. Looks very janky if set to false.
animationDuration: Double How long the animation should take. Affects both the startup animation and the animation when the range of the y-axis adapts to onscreen points.
adaptAnimationType: ScrollableGraphViewAnimationType The animation style. Possible values:
  • ScrollableGraphViewAnimationType.EaseOut
  • ScrollableGraphViewAnimationType.Elastic
  • ScrollableGraphViewAnimationType.Custom
customAnimationEasingFunction: ((t: Double) -> Double)? If adaptAnimationType is set to .Custom, then this is the easing function you would like applied for the animation.
shouldAnimateOnStartup: Bool Whether or not the graph should animate to their positions when the graph is first displayed.

Reference Lines

Property Description
shouldShowReferenceLines: Bool Whether or not to show the y-axis reference lines and labels.
referenceLineColor: UIColor The colour for the reference lines.
referenceLineThickness: CGFloat The thickness of the reference lines.
referenceLinePosition: ScrollableGraphViewReferenceLinePosition Where the labels should be displayed on the reference lines. Possible values:
  • ScrollableGraphViewReferenceLinePosition.Left
  • ScrollableGraphViewReferenceLinePosition.Right
  • ScrollableGraphViewReferenceLinePosition.Both
referenceLineType: ScrollableGraphViewReferenceLineType The type of reference lines. Currently only .Cover is available.
numberOfIntermediateReferenceLines: Int How many reference lines should be between the minimum and maximum reference lines. If you want a total of 4 reference lines, you would set this to 2. This can be set to 0 for no intermediate reference lines.This can be used to create reference lines at specific intervals. If the desired result is to have a reference line at every 10 units on the y-axis, you could, for example, set rangeMax to 100, rangeMin to 0 and numberOfIntermediateReferenceLines to 9.
shouldAddLabelsToIntermediateReferenceLines: Bool Whether or not to add labels to the intermediate reference lines.
shouldAddUnitsToIntermediateReferenceLineLabels: Bool Whether or not to add units specified by the referenceLineUnits variable to the labels on the intermediate reference lines.

Reference Line Labels

Property Description
referenceLineLabelFont: UIFont The font to be used for the reference line labels.
referenceLineLabelColor: UIColor The colour of the reference line labels.
shouldShowReferenceLineUnits: Bool Whether or not to show the units on the reference lines.
referenceLineUnits: String? The units that the y-axis is in. This string is used for labels on the reference lines.
referenceLineNumberOfDecimalPlaces: Int The number of decimal places that should be shown on the reference line labels.

Data Point Labels (x-axis)

Property Description
shouldShowLabels: Bool Whether or not to show the labels on the x-axis for each point.
dataPointLabelTopMargin: CGFloat How far from the "minimum" reference line the data point labels should be rendered.
dataPointLabelBottomMargin: CGFloat How far from the bottom of the view the data point labels should be rendered.
dataPointLabelFont: UIFont? The font for the data point labels.
dataPointLabelColor: UIColor The colour for the data point labels.
dataPointLabelsSparsity: Int Used to force the graph to show every n-th dataPoint label

Customisation Examples

Note: Examples here use a "colorFromHex" extension for UIColor.

Default

dark

let graphView = ScrollableGraphView(frame: frame)
graphView.setData(data, withLabels: labels)
self.view.addSubview(graphView)

Smooth Dark

dark

let graphView = ScrollableGraphView(frame: frame)

graphView.backgroundFillColor = UIColor.colorFromHex("#333333")

graphView.rangeMax = 50

graphView.lineWidth = 1
graphView.lineColor = UIColor.colorFromHex("#777777")
graphView.lineStyle = ScrollableGraphViewLineStyle.Smooth

graphView.shouldFill = true
graphView.fillType = ScrollableGraphViewFillType.Gradient
graphView.fillColor = UIColor.colorFromHex("#555555")
graphView.fillGradientType = ScrollableGraphViewGradientType.Linear
graphView.fillGradientStartColor = UIColor.colorFromHex("#555555")
graphView.fillGradientEndColor = UIColor.colorFromHex("#444444")

graphView.dataPointSpacing = 80
graphView.dataPointSize = 2
graphView.dataPointFillColor = UIColor.whiteColor()

graphView.referenceLineLabelFont = UIFont.boldSystemFontOfSize(8)
graphView.referenceLineColor = UIColor.whiteColor().colorWithAlphaComponent(0.2)
graphView.referenceLineLabelColor = UIColor.whiteColor()
graphView.dataPointLabelColor = UIColor.whiteColor().colorWithAlphaComponent(0.5)

graphView.setData(data, withLabels: labels)
self.view.addSubview(graphView)

Bar Dark (Bar layer thanks to @RedBlueThing)

bar

let graphView = ScrollableGraphView(frame:frame)  

// Disable the lines and data points.
graphView.shouldDrawDataPoint = false
graphView.lineColor = UIColor.clearColor()

// Tell the graph it should draw the bar layer instead.
graphView.shouldDrawBarLayer = true

// Customise the bar.
graphView.barWidth = 25
graphView.barLineWidth = 1
graphView.barLineColor = UIColor.colorFromHex("#777777")
graphView.barColor = UIColor.colorFromHex("#555555")
graphView.backgroundFillColor = UIColor.colorFromHex("#333333")

graphView.referenceLineLabelFont = UIFont.boldSystemFontOfSize(8)
graphView.referenceLineColor = UIColor.whiteColor().colorWithAlphaComponent(0.2)
graphView.referenceLineLabelColor = UIColor.whiteColor()
graphView.numberOfIntermediateReferenceLines = 5
graphView.dataPointLabelColor = UIColor.whiteColor().colorWithAlphaComponent(0.5)

graphView.shouldAnimateOnStartup = true
graphView.shouldAdaptRange = true
graphView.adaptAnimationType = ScrollableGraphViewAnimationType.Elastic
graphView.animationDuration = 1.5
graphView.rangeMax = 50
graphView.shouldRangeAlwaysStartAtZero = true

Dot

dot

let graphView = ScrollableGraphView(frame:frame)
graphView.backgroundFillColor = UIColor.colorFromHex("#00BFFF")
graphView.lineColor = UIColor.clearColor()

graphView.dataPointSize = 5
graphView.dataPointSpacing = 80
graphView.dataPointLabelFont = UIFont.boldSystemFontOfSize(10)
graphView.dataPointLabelColor = UIColor.whiteColor()
graphView.dataPointFillColor = UIColor.whiteColor()

graphView.referenceLineLabelFont = UIFont.boldSystemFontOfSize(10)
graphView.referenceLineColor = UIColor.whiteColor().colorWithAlphaComponent(0.5)
graphView.referenceLineLabelColor = UIColor.whiteColor()
graphView.referenceLinePosition = ScrollableGraphViewReferenceLinePosition.Both

graphView.numberOfIntermediateReferenceLines = 9

graphView.rangeMax = 50

self.view.addSubview(graphView)

Pink Mountain

pink

let graphView = ScrollableGraphView(frame:frame)
graphView.backgroundFillColor = UIColor.colorFromHex("#222222")
graphView.lineColor = UIColor.clearColor()

graphView.shouldFill = true
graphView.fillColor = UIColor.colorFromHex("#FF0080")

graphView.shouldDrawDataPoint = false
graphView.dataPointSpacing = 80
graphView.dataPointLabelFont = UIFont.boldSystemFontOfSize(10)
graphView.dataPointLabelColor = UIColor.whiteColor()

graphView.referenceLineThickness = 1
graphView.referenceLineLabelFont = UIFont.boldSystemFontOfSize(10)
graphView.referenceLineColor = UIColor.whiteColor().colorWithAlphaComponent(0.5)
graphView.referenceLineLabelColor = UIColor.whiteColor()
graphView.referenceLinePosition = ScrollableGraphViewReferenceLinePosition.Both

graphView.numberOfIntermediateReferenceLines = 1

graphView.rangeMax = 50

self.view.addSubview(graphView)

Solid Pink with Margins

You can use the top and bottom margin to leave space for other content:

pink_margins

let graphView = ScrollableGraphView(frame:frame)

graphView.bottomMargin = 350
graphView.topMargin = 20

graphView.backgroundFillColor = UIColor.colorFromHex("#222222")
graphView.lineColor = UIColor.clearColor()
graphView.lineStyle = ScrollableGraphViewLineStyle.Smooth

graphView.shouldFill = true
graphView.fillColor = UIColor.colorFromHex("#FF0080")

graphView.shouldDrawDataPoint = false
graphView.dataPointSpacing = 80
graphView.dataPointLabelFont = UIFont.boldSystemFontOfSize(10)
graphView.dataPointLabelColor = UIColor.whiteColor()

graphView.referenceLineThickness = 1
graphView.referenceLineLabelFont = UIFont.boldSystemFontOfSize(10)
graphView.referenceLineColor = UIColor.whiteColor().colorWithAlphaComponent(0.25)
graphView.referenceLineLabelColor = UIColor.whiteColor()

graphView.numberOfIntermediateReferenceLines = 0

graphView.rangeMax = 50

self.view.addSubview(graphView)

Improvements

Pull requests, improvements & criticisms to any and all of the code are more than welcome.

Known Issues

If you find any bugs please create an issue on Github.

Other

Follow me on twitter for interesting updates (read: gifs) about other things that I make.