Drawing Tools

The DrawingTools trait manages the active drawing tool and undo/redo history on any chart view. Both ChartView and ChartView implement this trait, enabling tool and history management to be written once and used with either view.

Import

use navi_chart::{ChartView, ChartView, DrawingTools, DrawingToolId};

Usage

use navi_chart::{DrawingTools, DrawingToolId};

fn activate_tool<C>(cv: &C, id: DrawingToolId)
where
    C: DrawingTools,
{
    cv.set_tool(id);
}

fn handle_keyboard_shortcut<C>(cv: &C, key: &str)
where
    C: DrawingTools,
{
    match key {
        "z" => { if cv.can_undo() { cv.undo(); } }
        "y" => { if cv.can_redo() { cv.redo(); } }
        "Escape" => cv.cancel_drawing(),
        _ => {}
    }
}

The tool is identified by the [DrawingToolId] enum, so unknown names are rejected at compile time and set_tool returns true for every valid variant.

Method Reference

Method	Description
undo()	Undo the last annotation creation, deletion, or modification. No-op if the history is empty.
redo()	Redo the last undone action. No-op if there is nothing to redo.
can_undo()	Return true if there is at least one action to undo.
can_redo()	Return true if there is at least one action to redo.
finalize_pending_drawing()	Force-complete an in-progress multi-point drawing (e.g. a polyline or Elliott wave) at the current number of points. Has no effect if no drawing is in progress.
cancel_drawing()	Cancel the current in-progress drawing without creating an annotation. Resets the tool to pointer mode unless sticky mode is active.
set_tool(id)	Activate the [DrawingToolId] variant. Pass DrawingToolId::Pointer to return to selection mode. Returns true after the switch is queued.
active_tool()	Return the [DrawingToolId] of the currently active tool.
set_sticky_tool(sticky)	Enable or disable sticky mode. When true, the tool stays active after each drawing is finalised — useful for placing multiple copies of the same shape without re-selecting the tool.
is_sticky_tool()	Return true if sticky mode is enabled.

Tool IDs

DrawingToolId enumerates every tool the chart view can host.

Category	Variant	Description
Mode	Pointer	Default pan / zoom / select mode
	TextEditing	Inline text editor (entered automatically; rarely set by hand)
Lines	Trendline	Trend line
	Ray	Half-line extending past p1
	ExtendedLine	Infinite line through two points
	Hline	Horizontal line at a fixed price
	Hray	Horizontal ray from p0 rightward
	Vline	Vertical line at a fixed time
	Crossline	Horizontal + vertical cross
	InfoLine	Trend line with Δprice / % / angle info
	TrendAngle	Trend line with angle arc
Shapes	Rect	Axis-aligned rectangle
	Circle	Circle
	Ellipse	Ellipse
	Triangle	Three-point triangle
	RotatedRect	Free-angle rectangle
	Polyline	Multi-point polyline (double-click to finish)
Arrows	Arrow	Line with arrowhead
	ArrowMarkUp	Upward arrow marker
	ArrowMarkDown	Downward arrow marker
	ArrowMarker	Free-rotating arrow marker
Channels	ParallelChannel	Two parallel trend lines
	FlatTopBottom	Two horizontal lines
	DisjointChannel	Two independent trend lines
	RegressionTrend	Linear regression channel
Text & Labels	Text	Editable text label
	Note	Text bubble
	Callout	Speech callout
	PriceNote	Text with price-axis label
	PriceLabel	Alias for PriceNote accepted by the parser
	Emoji	Emoji / glyph marker
Fibonacci	FibRetracement	Fibonacci retracement levels
	FibExtension	Fibonacci extension levels
	FibChannel	Fibonacci channel
	FibTimezone	Fibonacci time zones
	FibFan	Fibonacci fan rays
	FibCircles	Fibonacci circles
	FibArcs	Fib speed resistance arcs
	FibTrendBasedExtension	Trend-based Fibonacci extension
	FibWedge	Fibonacci wedge
	FibSpiral	Fibonacci spiral
Pitchfork	Pitchfork	Andrews' pitchfork
	SchiffPitchfork	Schiff pitchfork
	ModifiedSchiffPitchfork	Modified Schiff pitchfork
	InsidePitchfork	Inside pitchfork
Gann	GannBox	Gann box
	GannSquare	Gann square
	GannSquareFixed	Gann square (fixed aspect ratio)
	GannFan	Gann fan
Measurement	PriceRange	Price range ruler
	DateRange	Date range ruler
	DateAndPriceRange	Combined ruler
Brushes	Brush	Free-hand brush stroke
	Highlighter	Semi-transparent highlight
Position	LongPosition	Long risk/reward box
	ShortPosition	Short risk/reward box
	PositionForecast	Forecast cone
Cycles	CyclicLines	Equally-spaced vertical lines
	TimeCycles	Semicircular arc series
	SineLine	Sine wave
Chart Patterns	XabcdPattern, CypherPattern, AbcdPattern, HeadAndShoulders, TrianglePattern, ThreeDrivesPattern	Harmonic and chart patterns
Elliott Waves	ElliottImpulseWave, ElliottCorrectiveWave, ElliottTriangleWave, ElliottDoubleCombo, ElliottTripleCombo	Elliott wave counts
Volume Profile	AnchoredVwap, VolumeProfileFixedRange, VolumeProfileAnchored	Volume analysis tools
Curves	Path, Arc, Curve, DoubleCurve	Multi-point curves (path is double-click to finish)
Misc	BarPattern, GhostFeed, Sector	Miscellaneous tools

Sticky Mode

In sticky mode the tool remains active after each drawing is finalised, so the user can place multiple annotations of the same kind consecutively without re-selecting the tool:

// Enable sticky mode before activating a tool
cv.set_sticky_tool(true);
cv.set_tool(DrawingToolId::Trendline);

// The tool stays as Trendline after each line is drawn.
// Revert to normal single-shot mode:
cv.set_sticky_tool(false);

Undo / Redo Integration

Wire undo and redo to keyboard shortcuts and toolbar buttons:

use navi_chart::DrawingTools;

fn build_toolbar_state<C>(cv: &C) -> ToolbarState
where
    C: DrawingTools,
{
    ToolbarState {
        undo_enabled: cv.can_undo(),
        redo_enabled: cv.can_redo(),
        active_tool: cv.active_tool(),
        sticky: cv.is_sticky_tool(),
    }
}

fn on_undo_click<C>(cv: &C)
where
    C: DrawingTools,
{
    cv.undo();
    // Rebuild toolbar state to reflect updated can_undo / can_redo
}

Every add_annotation, update_annotation, remove_annotation, clear_annotations, and selection-mutation call (e.g. delete_selected_annotation) is tracked in the undo history automatically — no extra wiring is needed.