You can have a dynamic list of dropdown options based on the value of another dropdown. You can choose the first dropdown's choice and have the second dropdown only show options based on the first dropdown selected.
A common example of this is to have a user select a country and then show the relevant states based on the country that they selected.
Let's say that the Category and Sub-Category are related as shown below.
If you select Mobile in the first dropdown, you'll see the options of only this category. To do this, we need to use conditional statements in the second dropdown. No workflows are required.
Create 2 dropdowns as you normally would. Fill the Choices of the first dropdown as you'd like. In the second dropdown, fill the Choices with sub-categories of any category. The choices that you mention here don't matter. You can even type your name over here and it won't make any difference, but don't leave it blank or else it won't work.
Go to the Conditionals tab of the second dropdown. Create a new condition that when 1st Dropdown's value is Mobile, the Choices will be as you define.
And that's it. The Choices of the second dropdown will vary depending upon the option selected in the first dropdown.
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