How to change the title for the Hover icons on the tools panel

[somebody]

I have multiple hover icons on the panel and want to change the titles for each of them from “Hover” to something more specific.

[nghenzi]

You need to modify the description property of the hooverTool tools — Bokeh 2.4.2 Documentation. For example

from bokeh.plotting import figure, show, save
from bokeh.models import ColumnDataSource, HoverTool, CustomJSHover, CustomJS

src = ColumnDataSource(data={'x':[0,1,2],'y':[2,3,1],'Fruit':['Banana','Orange','Apple'],'Veggie':['Brocolli','Spinach','Corn'],'hoverkey':['Fruitx','Fruitx','Veggiey']})

#make a tooltip dictionary based on hoverkey
tt_dict = {'Fruitx':[['Fruit:','@Fruit'],['X','@x']]
           ,'Veggiey':[['Veggie:','@Veggie'],['Y','@y']]
           }

f = figure()
r = f.scatter(x='x',y='y',source=src)

#instantiate a hovertool, pointing to the renderers we want
hvr = HoverTool(renderers=[r])  #but not spec'ing any tooltips for now

#customjs attached to the callback:
cb = CustomJS(args=dict(hvr=hvr, src=src, tt_dict=tt_dict) #pass in both the CDS and the HoverTool and the tt_dict
              ,code='''
              //src.inspected.indices reports the indices of the source you are hovered over
              if (src.inspected.indices.length>0){
                      //get the hoverkey for the hovered item
                      const k = src.data['hoverkey'][src.inspected.indices[0]]
                      //use tt_dict to set the tooltips to that key's value in tt_dict
                      hvr.tooltips = tt_dict[k]
                      }
                      
              ''')
hvr.callback = cb #instructs this callback to trigger whenever the hoverTool function is called
hvr.description = 'custom title for hover '
f.add_tools(hvr)

show(f)

[somebody]

Thank you