protected int getGradientPartialColor(int minColor, int maxColor, float fraction) {
int alpha =
Math.round(fraction * Color.alpha(minColor) + (1 - fraction) * Color.alpha(maxColor));
int r = Math.round(fraction * Color.red(minColor) + (1 - fraction) * Color.red(maxColor));
int g = Math.round(fraction * Color.green(minColor) + (1 - fraction) * Color.green(maxColor));
int b = Math.round(fraction * Color.blue(minColor) + (1 - fraction) * Color.blue((maxColor)));
return Color.argb(alpha, r, g, b);
}
/**
* Draws a bar.
*
* @param canvas the canvas
* @param xMin the X axis minimum
* @param yMin the Y axis minimum
* @param xMax the X axis maximum
* @param yMax the Y axis maximum
* @param scale the scale index
* @param seriesIndex the current series index
* @param paint the paint
*/
protected void drawBar(
Canvas canvas,
float xMin,
float yMin,
float xMax,
float yMax,
int scale,
int seriesIndex,
Paint paint) {
// Fix negative bars issue in Android 4.2
float temp;
if (xMin > xMax) {
temp = xMin;
xMin = xMax;
xMax = temp;
}
if (yMin > yMax) {
temp = yMin;
yMin = yMax;
yMax = temp;
}
SimpleSeriesRenderer renderer = mRenderer.getSeriesRendererAt(seriesIndex);
if (renderer.isGradientEnabled()) {
float minY =
(float) toScreenPoint(new double[] {0, renderer.getGradientStopValue()}, scale)[1];
float maxY =
(float) toScreenPoint(new double[] {0, renderer.getGradientStartValue()}, scale)[1];
float gradientMinY = Math.max(minY, Math.min(yMin, yMax));
float gradientMaxY = Math.min(maxY, Math.max(yMin, yMax));
int gradientMinColor = renderer.getGradientStopColor();
int gradientMaxColor = renderer.getGradientStartColor();
int gradientStartColor = gradientMaxColor;
int gradientStopColor = gradientMinColor;
if (yMin < minY) {
paint.setColor(gradientMinColor);
canvas.drawRect(
Math.round(xMin), Math.round(yMin), Math.round(xMax), Math.round(gradientMinY), paint);
} else {
gradientStopColor =
getGradientPartialColor(
gradientMinColor, gradientMaxColor, (maxY - gradientMinY) / (maxY - minY));
}
if (yMax > maxY) {
paint.setColor(gradientMaxColor);
canvas.drawRect(
Math.round(xMin), Math.round(gradientMaxY), Math.round(xMax), Math.round(yMax), paint);
} else {
gradientStartColor =
getGradientPartialColor(
gradientMaxColor, gradientMinColor, (gradientMaxY - minY) / (maxY - minY));
}
GradientDrawable gradient =
new GradientDrawable(
Orientation.BOTTOM_TOP, new int[] {gradientStartColor, gradientStopColor});
gradient.setBounds(
Math.round(xMin), Math.round(gradientMinY), Math.round(xMax), Math.round(gradientMaxY));
gradient.draw(canvas);
} else {
if (Math.abs(yMin - yMax) < 1) {
if (yMin < yMax) {
yMax = yMin + 1;
} else {
yMax = yMin - 1;
}
}
canvas.drawRect(
Math.round(xMin), Math.round(yMin), Math.round(xMax), Math.round(yMax), paint);
}
}