Fluorite Cloud initialization crawl pit 2--camera preview

Here are two screenshots of the official development document of the Fluorite cloud.

Bloggers have been doing a preview of the camera in recent days (according to the official document of the Fluorite cloud)

However, the preview of the picture is always dark.

Studied for a few days and found the place where the problem was.

Note the methods that are marked in the following illustration

According to the development documentation--

public void Setplayverifycode (java.lang.String verifycode)

Incoming video encryption password for encrypting video decoding, which can invoke parameters when a error_inner_verifycode_need or Error_inner_verifycode_error error callback is received: Verifycode-Video Encryption password , the default is 6-bit verification code for the device
The image gets the default 6-bit verification code for the device (camera), and the user usually sets a direct password after getting the device (camera) when the user has set a password, the device default 6-bit verification will expire----preview screen (black screen) the encryption password (or the device's verification code) must be set before previewing

Here's the blogger code.