How to capture mouse clicks in dsp.SpectrumAnalyzer, and draw on plot

I would like to add my own interactivity to the dsp.SpectrumAnalyzer plot. I would like to receive a callback when the user clicks in the spectrum analyzer plot. This way, I can determine which frequency (x-axis value) the user clicked on.

Also, I would like to draw on the spectrum analyzer plot with my own drawing code.

Are either of these things possible? Can I somehow obtain access to the plot handle, or is it some low-level C/C++ routine that is drawing directly to the screen?