android - android中的Achart引擎自定义点样式

Question

您好，我想在 achartengine 的散点图中绘制自定义点样式。

是否可以使用图表引擎？如果是，那么该怎么做？

Answer 1

我可以通过覆盖图形 View 的 onDraw(Canvas canvas) 方法来使用自定义点样式

 protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    if (mCommonPointBitmap != null ) {
        float halfWitdhCommonPointBitmap = (float) mCommonPointBitmap.getWidth() / 2;
        float halfHeightCommonPointBitmap = (float) mCommonPointBitmap.getHeight() / 2;
        // float halfWitdhyouPointBitmap = (float) mYouPointBitmap.getWidth() / 2;
        // float halfHeightyouPointBitmap = (float) mYouPointBitmap.getHeight() / 2;
        List<double[]> screenPoints = getSeriesSelectionList();
        if (!CommonUtils.isCollectionNullOrEmpty(screenPoints)) {
            int[] margins = mXYChart.getRenderer().getMargins();
            // Info: margin order: top, left, bottom, right
            canvas.clipRect(getLeft() + margins[1], getTop() - margins[0], getRight() - margins[3], getBottom()
                    - margins[2]);
            for (int i = 0; i < screenPoints.size(); i++) {
                double[] screenPoint = screenPoints.get(i);
                if (screenPoint != null) {
                    float pointLeftX = (float) screenPoint[0] - halfWitdhCommonPointBitmap;
                    float pointTopY = (float) screenPoint[1] - halfHeightCommonPointBitmap;
                    canvas.drawBitmap(mCommonPointBitmap, pointLeftX, pointTopY, null);
                }
            }
        }
    }
}



 List<double[]> screenPoints = null;
    XYSeries xySeries = mXYChart.getDataset().getSeriesAt(0);
    int itemCount = xySeries.getItemCount();
    if (itemCount > 0) {
        screenPoints = new ArrayList<double[]>(itemCount);
        double[] realPoints = new double[2];
        for (int itemIndex = 0; itemIndex < itemCount; itemIndex++) {
            realPoints[0] = xySeries.getX(itemIndex);
            realPoints[1] = xySeries.getY(itemIndex);
            screenPoints.add(mXYChart.toScreenPoint(realPoints));
        }
    }
    return screenPoints;
}