I'm using MPAndroidChart library to make charts in my app. I need to create chart like the following one. I need gradient line on LineChart and it's color must be based on values. For example Red for high, Yellow for medium, Green for low.
As far as I tried I managed to get like the following.
I searched for a day to find a solution, but I can't find any solution. So if any of you know how to fix this or have any idea about this please do share with me. Thanks.
Solution from codereview.stackexchange.com worked for me.
protected void drawCubicBezier(ILineDataSet dataSet) {
...
// Get screen coordinates for min Y value
MPPointD pixelForValues = trans.getPixelForValues(0, minDy);
minDy = (float) pixelForValues.y;
MPPointD.recycleInstance(pixelForValues);
// Get screen coordinates for max Y value
pixelForValues = trans.getPixelForValues(0, maxDy);
maxDy = (float) pixelForValues.y;
MPPointD.recycleInstance(pixelForValues);
// Get screen coordinates for 0 value
pixelForValues = trans.getPixelForValues(0, 0);
float zeroDy = (float) pixelForValues.y;
MPPointD.recycleInstance(pixelForValues);
float range = minDy - maxDy;
float zeroPointNormalized = Math.max((zeroDy - maxDy) / range, 0);
linearGradient = new LinearGradient(
0, maxDy, 0, minDy,
new int[]{Color.RED, Color.RED, Color.BLUE, Color.BLUE},
new float[]{0, zeroPointNormalized, zeroPointNormalized, 1f},
Shader.TileMode.REPEAT);
paint.setShader(linearGradient);
...
mBitmapCanvas.drawPath(cubicPath, paint);
}
Try William Chart and use this method:
int[] colors = { getResources().getColor(R.color.menu_text),
getResources().getColor(android.R.color.white) };
float[] index = { 0, 1 };
dataset.setGradientFill(colors, index);
Edit 1: In MPChart, You can use
Paint paint = mChart.getRenderer().getPaintRender();
paint.setShader(new LinearGradient(0, 0, 0, 40, Color.YELLOW, Color.RED, Shader.TileMode.REPEAT));
