Transitioning a task to done with its subtask is in todo state.

[Boluwatife Onafujabi]

Based on this "If a task that you add is actually a group of smaller tasks, you can create sub-tasks and assign them to different people. The task will not be able to move to Done, until all the subtasks are complete as well. " I created a task and subtask, the subtask was not done but when i moved the task to done i was able to do that which is not meant to happen right?

[Rambabu Patina _Appfire_ · Accepted solution]

JIRA does not have a native functionality to close a sub task once the parent issue is closed.

If you want to define a rule like close all the sub-tasks before parent closes, you will need to set up a post function. For that you can add  “Sub-Task Blocking Condition” as Alana suggested or you can use third party add-ons.

[Alana Fernando · Accepted solution]

@Boluwatife Onafujabi, this is the behavior of jira though this is incorrect theoretically. 

anyway you can add  “Sub-Task Blocking Condition” in you workflow to Preventing issues from being closed while the sub-tasks are still open.

how to add “Sub-Task Blocking Condition”

[Boluwatife Onafujabi]

okay thank you

[Boluwatife Onafujabi]

One more thing please, i can't view my sub tasks issues on my board

[Alana Fernando]

I assume you are referring a scrum board here. unfortunately sub task are not visible in boards. But I guess this needs more confirmation. I am keeping this reply open ended. 

https://community.atlassian.com/t5/Agile-questions/how-are-subtasks-in-agile-boards-supposed-to-work/qaq-p/243686

Using your Scrum backlog

About the Scrum backlog

An issue will only be visible in the Scrum backlog if:

• the issue isn't a subtask,

[Boluwatife Onafujabi]

This is a task tracking project template not a scrum project. So basically just a jira core board.

[Alana Fernando]

@Boluwatife Onafujabi I guess i am not the best to advice on this. :( will you please raise another question regarding this? (to get expert attention) 

[Boluwatife Onafujabi]

Thank you @Alana Fernando