如何限制chartIQ库中的最小和最大缩放

Question

I work with chartIQ library: https://www.chartiq.com My target is to limit minimum and maximum chart zoom. How can i do it?

Answer 1

To set the minimum zoom you can set ChartEngine.minimumZoomTicks field.

http://documentation.chartiq.com/CIQ.ChartEngine.html#minimumZoomTicks

stxx.minimumZoomTicks=5; // when zoomed all the way in only 5 bars will show

There isn't a field that mirrors that functionality for zooming out I'm afraid, but what you are trying to accomplish can be achieved by utilizing the prepend injection functionality along with setting the zoomOutSpeed to 1.

http://documentation.chartiq.com/tutorial-Using%20the%20Injection%20API.html

http://documentation.chartiq.com/CIQ.ChartEngine.html#preferences%5B%60zoomOutSpeed%60%5D

var stxx = yourChartInstance;
stxx.preferences.zoomOutSpeed=1;
stxx.prepend("zoomOut", function() {
    for(var chartName in stxx.charts){
        var chart=stxx.charts[chartName];
        chart.maxTicks=20; // this will set the maximum number of bars on the screen, along with zoomOutSpeed
    }
});

If you have any other questions please contact ChartIQ directly at support@chartiq.com.