How to populate second dropdown(source) list based on the first dropdown(host) selection?

[navd]

Here is my sample code that I am using

<form>
   <label>raw data</label>
    <fieldset submitButton="true" autoRun="true">
<input type="dropdown" token="host" searchWhenChanged="true">
  <label>Select Host Name</label>
  <choice value="*">ALL</choice>
  <fieldForLabel>host</fieldForLabel>
  <fieldForValue>host</fieldForValue>
  <search>
    <query>index=abcd |dedup host</query>
    <earliest>-24h@h</earliest>
    <latest>now</latest>
  </search>
</input>
<input type="time" token="time_range" searchWhenChanged="true">
  <label>Select Time Range</label>
  <default>
    <earliest>-24h@h</earliest>
    <latest>now</latest>
  </default>
</input>
<input type="dropdown" token="source" searchWhenChanged="true">
  <label>Select Source</label>
  <choice value="*">ALL</choice>
  <fieldForLabel>source</fieldForLabel>
  <fieldForValue>source</fieldForValue>
  <search>
    <query>index=abcd |dedup source</query>
    <earliest>-24h@h</earliest>
    <latest>now</latest>
  </search>
</input>
  </fieldset>
  <row>
    <panel>
     <event>
    <search>
      <query>index="abcd" host=$host$</query>
      <earliest>$time_range.earliest$</earliest>
      <latest>$time_range.latest$</latest>
    </search>
    <option name="list.drilldown">full</option>
    <option name="refresh.display">progressbar</option>
  </event>
  </panel>
  </row>
</form>

[pradeepkumarg · Accepted solution]

Update your search for source and include host token

     index=abcd host=$host$ |dedup source

[navd]

I updated the search for source and I could see source based on host selected, but when I choose any option from the source I couldn,t see the results/events based on the source selected

[pradeepkumarg]

because you are not using source filter in your final search

add source=$source$ in your final search

[navd]

got it thanks