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androidmpandroidchart

MPAndroidChart: Listen for click events on xAxis labels

How do I get an onClickListener for the xAxis labels? If this is not possible, is there any other way to receive click events on the xAxis labels?

Solution

  • The xAxis labels are not actually instances of View. Instead, they are rendered directly onto the canvas by MPAndroidChart. So you can't have a OnClickListener for them.

    The way to do what you want, instead, is to implement a custom OnChartGestureListener. The javadoc for that class is here

    mChart.setOnChartGestureListener(new MyChartGestureListener());

    In your MyChartGestureListener you would override onChartSingleTapped(MotionEvent me):

    @Override
public void onChartSingleTapped(MotionEvent me) {
    float tappedX = me.getX();
    float tappedY = me.getY();
    MPPointD point = mChart.getTransformer(YAxis.AxisDependency.LEFT).getValuesByTouchPoint(tappedX, tappedY);
    Log.d(TAG, "tapped at: " + point.x + "," + point.y);
}

    The snippet above shows how to get the x and y values from the MotionEvent. You would then need some logic to check if you are single tapping a label and not another part of the chart. Perhaps a conditional like:

    if ((point.y) < labelYValue) {
     Log.d(TAG, "tapped on label for x-value: " + point.x);
}

    Or you could probably use the raw y from the MotionEvent if you prefer.