You have entered a wrong query for loading flutter preview.

Reason:

query paramter "src" was empty

Input:

{}

1. src is required.
src can be rather url or actual code content, written in js or dart. the both following data should be filled with below queries.

2. mode is required.
to specify the mode of the src. it can be rather "source" or "url". if "source" is givven frame will use source as-is to load the flutter frame. if "url" is givven, frame will fetch the content from the "url" it can be gist url (raw).

3. language is required.
to specify the code language of the source. it can be rather dart or compiled js. if dart is givven, frame will compile this to js and load the preview (you don't need to care about this part at all.).

Example

Click here for the example demo of flutter frames