Coordinates of box of annotations in matplotlib

Question

How can I get the coordinates of the box displayed in the following plot?

fig, ax = subplots()
x = ax.annotate('text', xy=(0.5, 0), xytext=(0.0,0.7), 
                ha='center', va='bottom',
                bbox=dict(boxstyle='round', fc='gray', alpha=0.5),
                arrowprops=dict(arrowstyle='->', color='blue'))

I tried to inspect the properties of this object, but I couldn't find something suited to this purpose. There is a property called get_bbox_patch() which could be on the right track, however, I get results in a different coordinate system (or associated to a different property)

y = x.get_bbox_patch()
y.get_width()
63.265625

Thanks a lot!

Answer 1

ax.figure.canvas.draw()
bbox = x.get_window_extent()

will return a Bbox object for your text in display units (the draw is necessary so that the text is rendered and actually has a display size). You can then use the transforms to convert it to which ever coordinate system you want. Ex

bbox_data = ax.transData.inverted().transform(bbox)