If you take the example line chart from the documentation and append &chg=1,0, you get vertical grid lines as expected. If you add &chg=0,1 instead, horizontal grid lines are not drawn.
Example Line Chart Vertical
Example Line Chart Horizontal
Looking at the toChartJs function in google_image_charts.js I note that it calls setGridLines() twice, and the file also contains two separate implementations of the setGridLines function. The first sets maxTicksLimit and the second sets gridLines.display and gridLines.drawOnChartArea.
I don't know how Javascript handles calls to a function that's implemented twice, but I note that if I append &format=chartjs-config to the URLs, the one that works has drawOnChartArea set to true and the one that doesn't work has drawOnChartArea set to false.
I don't have a suitable test environment to suggest a fix, but hopefully the above information is helpful in identifying the problem. Thanks so much in advance.
If you take the example line chart from the documentation and append
&chg=1,0, you get vertical grid lines as expected. If you add&chg=0,1instead, horizontal grid lines are not drawn.Example Line Chart Vertical
Example Line Chart Horizontal
Looking at the
toChartJsfunction ingoogle_image_charts.jsI note that it callssetGridLines()twice, and the file also contains two separate implementations of thesetGridLinesfunction. The first setsmaxTicksLimitand the second setsgridLines.displayandgridLines.drawOnChartArea.I don't know how Javascript handles calls to a function that's implemented twice, but I note that if I append
&format=chartjs-configto the URLs, the one that works hasdrawOnChartAreaset totrueand the one that doesn't work hasdrawOnChartAreaset tofalse.I don't have a suitable test environment to suggest a fix, but hopefully the above information is helpful in identifying the problem. Thanks so much in advance.