gochart

README

gochart

Simple chart implementation using fyne and gg libraries

Dependencies

• gg (https://github.com/fogleman/gg)
• fyne (https://github.com/fyne-io/fyne)

Functionality

Currently only BarChart and LineChart are provided. More types can be created by embedding BaseChart and implementing the required methods:

• Required by Chart interface

      // A "contructor" like NewAwesomeChart should be created as well
      BeginDraw(dc *gg.Context, x, y float64)
      DrawPoint(dc *gg.Context, x, y, yOffset float64, int, image.Rectangle)
      EndDraw(dc *gg.Context)

• Required by Fyne (follow the guidelines at Extending Widgets) for more information:

      CreateRenderer() fyne.WidgetRenderer

Documentation

Index

• func SetFont(path string, points float64) error
• type BarChart
  • func NewBarChart(w, h int) *BarChart
  • func (c *BarChart) BeginDraw(dc *gg.Context, x, y float64)
  • func (l *BarChart) CreateRenderer() fyne.WidgetRenderer
  • func (c *BarChart) DrawPoint(dc *gg.Context, x, y, yOffset float64, pointCount int, rect image.Rectangle)
  • func (c *BarChart) EndDraw(dc *gg.Context)
• type BaseChart
  • func NewBaseChart(w, h int) *BaseChart
  • func (c *BaseChart) BeginDraw(dc *gg.Context, x, y float64)
  • func (l *BaseChart) CreateRenderer() fyne.WidgetRenderer
  • func (c *BaseChart) DragEnd()
  • func (c *BaseChart) Dragged(event *fyne.DragEvent)
  • func (c *BaseChart) DrawCursor(dc *gg.Context, ratioX float64)
  • func (c *BaseChart) DrawFrame(dc *gg.Context, ratioX, ratioY, yOffset, height, width, xSpan, ySpan float64)
  • func (c *BaseChart) DrawPoint(dc *gg.Context, x, y, yOffset float64, pointCount int, rect image.Rectangle)
  • func (c *BaseChart) EndDraw(dc *gg.Context)
  • func (c *BaseChart) GetData() ([]float64, []float64)
  • func (c *BaseChart) GetGrowY() bool
  • func (c *BaseChart) GetMargin() float64
  • func (c *BaseChart) GetMouse() (float32, float32)
  • func (c *BaseChart) GetScreen() image.Image
  • func (c *BaseChart) GetShowLabel() bool
  • func (c *BaseChart) ResizeIfNeeded(w, h int)
  • func (c *BaseChart) SetData(x, y []float64)
  • func (c *BaseChart) SetGrowY(grow bool)
• type Chart
• type ChartRenderer
  • func (l *ChartRenderer) Destroy()
  • func (l *ChartRenderer) Layout(size fyne.Size)
  • func (l *ChartRenderer) MinSize() fyne.Size
  • func (l *ChartRenderer) Objects() []fyne.CanvasObject
  • func (l *ChartRenderer) Refresh()
• type LineChart
  • func NewLineChart(w, h int) *LineChart
  • func (c *LineChart) BeginDraw(dc *gg.Context, x, y float64)
  • func (l *LineChart) CreateRenderer() fyne.WidgetRenderer
  • func (c *LineChart) DrawPoint(dc *gg.Context, x, y, yOffset float64, pointCount int, rect image.Rectangle)
  • func (c *LineChart) EndDraw(dc *gg.Context)

Functions

func SetFont

func SetFont(path string, points float64) error

Types

type BarChart

type BarChart struct {
	BaseChart
}

func NewBarChart

func NewBarChart(w, h int) *BarChart

func (*BarChart) BeginDraw

func (c *BarChart) BeginDraw(dc *gg.Context, x, y float64)

func (*BarChart) CreateRenderer

func (l *BarChart) CreateRenderer() fyne.WidgetRenderer

func (*BarChart) DrawPoint

func (c *BarChart) DrawPoint(dc *gg.Context, x, y, yOffset float64, pointCount int, rect image.Rectangle)

func (*BarChart) EndDraw

func (c *BarChart) EndDraw(dc *gg.Context)

type BaseChart

type BaseChart struct {
	widget.BaseWidget
	Screen image.Image
	// contains filtered or unexported fields
}

func NewBaseChart

func NewBaseChart(w, h int) *BaseChart

func (*BaseChart) BeginDraw

func (c *BaseChart) BeginDraw(dc *gg.Context, x, y float64)

func (*BaseChart) CreateRenderer

func (l *BaseChart) CreateRenderer() fyne.WidgetRenderer

func (*BaseChart) DragEnd

func (c *BaseChart) DragEnd()

func (*BaseChart) Dragged

func (c *BaseChart) Dragged(event *fyne.DragEvent)

Events A minimum implementation is provided so the cursor is is tracked when it's over the chart area

func (*BaseChart) DrawCursor

func (c *BaseChart) DrawCursor(dc *gg.Context, ratioX float64)

func (*BaseChart) DrawFrame

func (c *BaseChart) DrawFrame(dc *gg.Context, ratioX, ratioY, yOffset, height, width, xSpan, ySpan float64)

func (*BaseChart) DrawPoint

func (c *BaseChart) DrawPoint(dc *gg.Context, x, y, yOffset float64, pointCount int, rect image.Rectangle)

func (*BaseChart) EndDraw

func (c *BaseChart) EndDraw(dc *gg.Context)

func (*BaseChart) GetData

func (c *BaseChart) GetData() ([]float64, []float64)

func (*BaseChart) GetGrowY

func (c *BaseChart) GetGrowY() bool

func (*BaseChart) GetMargin

func (c *BaseChart) GetMargin() float64

func (*BaseChart) GetMouse

func (c *BaseChart) GetMouse() (float32, float32)

func (*BaseChart) GetScreen

func (c *BaseChart) GetScreen() image.Image

func (*BaseChart) GetShowLabel

func (c *BaseChart) GetShowLabel() bool

func (*BaseChart) ResizeIfNeeded

func (c *BaseChart) ResizeIfNeeded(w, h int)

func (*BaseChart) SetData

func (c *BaseChart) SetData(x, y []float64)

func (*BaseChart) SetGrowY

func (c *BaseChart) SetGrowY(grow bool)

type Chart

type Chart interface {
	fyne.Widget
	SetGrowY(grow bool)
	SetData(x, y []float64)

	BeginDraw(dc *gg.Context, x, y float64)
	DrawPoint(dc *gg.Context, x, y, yOffset float64, pointCount int, rect image.Rectangle)
	EndDraw(dc *gg.Context)

	DrawCursor(dc *gg.Context, ratioX float64)
	DrawFrame(dc *gg.Context, ratioX, ratioY, yOffset, height, width, xSpan, ySpan float64)

	ResizeIfNeeded(w, h int)

	GetData() ([]float64, []float64)
	GetScreen() image.Image
	GetGrowY() bool
	GetMargin() float64
	GetMouse() (float32, float32)
	GetShowLabel() bool
}

type ChartRenderer

type ChartRenderer struct {
	// contains filtered or unexported fields
}

func (*ChartRenderer) Destroy

func (l *ChartRenderer) Destroy()

func (*ChartRenderer) Layout

func (l *ChartRenderer) Layout(size fyne.Size)

func (*ChartRenderer) MinSize

func (l *ChartRenderer) MinSize() fyne.Size

func (*ChartRenderer) Objects

func (l *ChartRenderer) Objects() []fyne.CanvasObject

func (*ChartRenderer) Refresh

func (l *ChartRenderer) Refresh()

type LineChart

type LineChart struct {
	BaseChart
}

func NewLineChart

func NewLineChart(w, h int) *LineChart

func (*LineChart) BeginDraw

func (c *LineChart) BeginDraw(dc *gg.Context, x, y float64)

func (*LineChart) CreateRenderer

func (l *LineChart) CreateRenderer() fyne.WidgetRenderer

func (*LineChart) DrawPoint

func (c *LineChart) DrawPoint(dc *gg.Context, x, y, yOffset float64, pointCount int, rect image.Rectangle)

func (*LineChart) EndDraw

func (c *LineChart) EndDraw(dc *gg.Context)