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androidgraphandroidplot

Custom points on graph using AndroidPlot


Anyone that has used the AndroidPlot library tell me how would I go about drawing custom points on a graph. So far I'm using LineAndPointRenderer class and settings lines to transparent. I would like to at least change the size of the dot but if possible have a custom image instead.

P.S someone with 1500 rep needs to create a "AndroidPlot" tag.


Solution

  • Solved the problem by creating my own renderer.

    import android.graphics.*;
    
    import com.androidplot.series.XYSeries;
    import com.androidplot.exception.PlotRenderException;
    import com.androidplot.util.ValPixConverter;
    import com.androidplot.xy.LineAndPointFormatter;
    import com.androidplot.xy.XYPlot;
    import com.androidplot.xy.XYSeriesRenderer;
    
    
    public class CustomPointRenderer<FormatterType extends LineAndPointFormatter> extends XYSeriesRenderer<FormatterType> {
    
        private float circleWidth = 1;
    
        public CustomPointRenderer(XYPlot plot) {
            super(plot);
        }
    
        @Override
        public void onRender(Canvas canvas, RectF plotArea) throws PlotRenderException {
            for(XYSeries series : getPlot().getSeriesListForRenderer(this.getClass())) {
                drawSeries(canvas, plotArea, series, getFormatter(series));
            }
        }
        @Override
        protected void doDrawLegendIcon(Canvas canvas, RectF rect, FormatterType formatter) {
            // horizontal icon:
            float centerY = rect.centerY();
            float centerX = rect.centerX();
    
            if(formatter.getFillPaint() != null) {
                canvas.drawRect(rect, formatter.getFillPaint());
            }
            if(formatter.getLinePaint() != null) {
                canvas.drawLine(rect.left, rect.bottom, rect.right, rect.top, formatter.getLinePaint());
            }
    
            if(formatter.getVertexPaint() != null) {
                canvas.drawPoint(centerX, centerY, formatter.getVertexPaint());
            }
        }
    
        private void drawSeries(Canvas canvas, RectF plotArea, XYSeries series, LineAndPointFormatter formatter) throws PlotRenderException {
            PointF p = null;
            XYPlot plot = getPlot();
            int size = series.size();
    
            for (int i = 0; i < size; i++) {
                Number y = series.getY(i);
                Number x = series.getX(i);
    
                if (y != null && x != null) {
                    p = ValPixConverter.valToPix(x, y, plotArea,
                                plot.getCalculatedMinX(),
                                plot.getCalculatedMaxX(),
                                plot.getCalculatedMinY(),
                                plot.getCalculatedMaxY());
    
                    if (formatter.getVertexPaint() != null) {
                        boolean offScreen = p.x > plotArea.right || p.y > plotArea.bottom || p.x < plotArea.left || p.y < plotArea.top; 
                        if(!offScreen)
                            canvas.drawCircle(p.x, p.y - circleWidth, circleWidth, formatter.getVertexPaint());
                    }               
                }
            } 
        }
    
        public void setWidth(float width){
            circleWidth = width;
        }
    }