In Splunk 5, you will probably need to use Advanced XML to do what you want. Here is a link to the 5.0 documentation:
Build a dashboard using advanced XML
However, I found this Example app much more useful Splunk Dashboard Examples for 5.0. It's free and it shows a lot of advanced XML code...
"probably need to do" is not answer.
You are right, but then I thought perhaps that the advice in the duplicate question:
Do dashboards in Splunk 5.0 support dynamic date/time inputs?
didn't work for you. That question clearly pointed to the answer in the manual
Build and edit forms with simple XML
Did you read that and do what it suggested?
I read the http://docs.splunk.com/Documentation/Splunk/5.0/Viz/Buildandeditforms
and try and datetime picker is not displayed. And I do not know how to pass the earliest and last time to the querystring. Any idea?
Monthly OR Data
error
<!-- Create a text box; token is "series" -->
<!-- label: Label for the text box -->
<!-- default: A default value is not specified -->
<!-- seed: Upon first load, the text box specifies 'splunkd' -->
<!-- suffix: All tokens are followed by a * -->
<!-- If user does not specify text, then search uses '*' -->
<input type="text" token="series">
<label>sourcetype</label>
<default></default>
<seed>splunkd</seed>
<suffix>*</suffix>
</input>
<!-- Add default TimePicker -->
<input type="time" />
<table>
<searchString>error</searchString>
<title></title>
</table>