增加MPAndroidChart的条形图中所选列的宽度

Question

是否可以增加所选列的条形宽度？我想实现这样的目标。

Answer 1

找到了一种方法。我扩展了BarChartRenderer类并覆盖了drawHighlighted方法。

public class CustomBarChartRenderer extends BarChartRenderer {

public CustomBarChartRenderer(BarDataProvider chart, ChartAnimator animator, ViewPortHandler viewPortHandler) {
    super(chart, animator, viewPortHandler);
}

@Override
public void drawHighlighted(Canvas c, Highlight[] indices) {
    for (int i = 0; i < indices.length; i++) {

        Highlight h = indices[i];
        int index = h.getXIndex();

        BarData barData = mChart.getBarData();

        for (int j = 0; j < barData.getDataSetCount(); j++) {

            IBarDataSet set = barData.getDataSetByIndex(j);

            if (set.isVisible() && set.getEntryCount() > 0) {
                customDrawDataSet(c, set, j, index);
            }
        }
    }
}

protected void customDrawDataSet(Canvas c, IBarDataSet dataSet, int index, int selectedIndex) {
    Transformer trans = mChart.getTransformer(dataSet.getAxisDependency());

    mShadowPaint.setColor(dataSet.getBarShadowColor());

    float phaseX = mAnimator.getPhaseX();
    float phaseY = mAnimator.getPhaseY();

    // initialize the buffer
    BarBuffer buffer = mBarBuffers[index];
    buffer.setPhases(phaseX, phaseY);
    buffer.setBarSpace(dataSet.getBarSpace());
    buffer.setDataSet(index);
    buffer.setInverted(mChart.isInverted(dataSet.getAxisDependency()));

    buffer.feed(dataSet);

    trans.pointValuesToPixel(buffer.buffer);

    // draw the bar shadow before the values
    if (mChart.isDrawBarShadowEnabled()) {

        for (int j = 0; j < buffer.size(); j += 4) {

            if (!mViewPortHandler.isInBoundsLeft(buffer.buffer[j + 2]))
                continue;

            if (!mViewPortHandler.isInBoundsRight(buffer.buffer[j]))
                break;

            c.drawRect(buffer.buffer[j], mViewPortHandler.contentTop(),
                    buffer.buffer[j + 2],
                    mViewPortHandler.contentBottom(), mShadowPaint);
        }
    }

    // if multiple colors
    if (dataSet.getColors().size() > 1) {

        for (int j = 0; j < buffer.size(); j += 4) {

            mHighlightPaint.setColor(Color.rgb(255, 255, 255));
            mHighlightPaint.setAlpha(dataSet.getHighLightAlpha());

            if (!mViewPortHandler.isInBoundsLeft(buffer.buffer[j + 2]))
                continue;

            if (!mViewPortHandler.isInBoundsRight(buffer.buffer[j]))
                break;

            // Set the color for the currently drawn value. If the index
            // is
            // out of bounds, reuse colors.
            float left = 0f;
            float top = 0f;
            float right = 0f;
            float bottom = 0f;

            if( j == (selectedIndex * 4)) {
                left = buffer.buffer[j] - 10;
                top = buffer.buffer[j + 1];
                right = buffer.buffer[j + 2] + 10;
                bottom = buffer.buffer[j + 3];

                mRenderPaint.setColor(dataSet.getColor(j / 4));
            }
            else {
                left = buffer.buffer[j];
                top = buffer.buffer[j + 1];
                right = buffer.buffer[j + 2];
                bottom = buffer.buffer[j + 3];

                mRenderPaint = mHighlightPaint;
            }

            c.drawRect(left, top, right, bottom, mRenderPaint);
        }
    } else {

        mRenderPaint.setColor(dataSet.getColor());

        for (int j = 0; j < buffer.size(); j += 4) {

            mHighlightPaint.setColor(Color.rgb(255, 255, 255));
            mHighlightPaint.setAlpha(dataSet.getHighLightAlpha());

            if (!mViewPortHandler.isInBoundsLeft(buffer.buffer[j + 2]))
                continue;

            if (!mViewPortHandler.isInBoundsRight(buffer.buffer[j]))
                break;

            float left = 0f;
            float top = 0f;
            float right = 0f;
            float bottom = 0f;

            if( j == (selectedIndex * 4)) {
                left = buffer.buffer[j] - 10;
                top = buffer.buffer[j + 1];
                right = buffer.buffer[j + 2] + 10;
                bottom = buffer.buffer[j + 3];

                mRenderPaint.setColor(dataSet.getColor(j / 4));
            }
            else {
                left = buffer.buffer[j];
                top = buffer.buffer[j + 1];
                right = buffer.buffer[j + 2];
                bottom = buffer.buffer[j + 3];

                mRenderPaint = mHighlightPaint;
            }

            c.drawRect(left, top, right, bottom, mRenderPaint);
        }
    }
}