API 文档由 Go 源码生成,内容为英文。
type ChartPlot struct {
ChartLayout
// Plot is the data area inside the axes, where lines and bars are drawn.
Plot ui.Rect
}
ChartPlot reports where a chart painted, so the caller can turn a pointer
position into the hovered data point and place its own annotations.
构造函数
PaintAreaChart#
func PaintAreaChart(canvas *ui.Canvas, theme ui.Theme, bounds ui.Rect, id ui.ID, chart AreaChart, state *ChartState) ChartPlot
PaintAreaChart paints an area or line chart into bounds, with its legend,
axes, grid, series, the hover mark and tooltip for state's hovered point, and
registers the plot as the hit region id. It returns the geometry for turning
pointer positions into points; the caller feeds the result back through
ChartState.Hover from its own pointer and key events (ChartStepForKey).
A steady chart allocates nothing per paint once its state has warmed up.
PaintBarChart#
func PaintBarChart(canvas *ui.Canvas, theme ui.Theme, bounds ui.Rect, id ui.ID, chart BarChart, state *ChartState) ChartPlot
PaintBarChart paints a bar chart with the same chrome, state and hover model as
PaintAreaChart. Each category owns an equal band; the bars of a group sit side
by side, or pile up when Stack is set.
方法
Count#
func (plot ChartPlot) Count() int
Count is the number of data points.
IndexAt#
func (plot ChartPlot) IndexAt(x float32) int
IndexAt returns the data point nearest to canvas X, or -1 when there is none.
Feed it the pointer position to drive ChartState.Hover.
PointX#
func (plot ChartPlot) PointX(index int) float32
PointX is the canvas X of data point index.
ValueY#
func (plot ChartPlot) ValueY(value float32) float32
ValueY is the canvas Y of a Y value.