How to make a framebuffer that will be updated by another task?

Question

We have one framebuffer, and the framebuffer will be overlap by other buffer by another task. So during the overlap of the framebuffer, EW can't update the framebuffer.  How to solve this problem? Using the offscreen buffer or something else?  Is there a sample souce about it?

Answer 1

I'm not sure whether I understand your question. Generally, EW created application is limited to run within one GUI task/thread only. In any case you should try to call EW functions from other threads. This will lead to fatal inpredicable errors.

If you have several tasks, you need a kind of interprocess communication. This can be a message queue or a system event. The second task uses this IPC service to send a message to the GUI task. The GUI task, in turn, receives the message and performs the associated operation in its own context. In the simplest case you can use a global C variable declared as volatile. The second task sets the variable and the GUI task evaluates it periodically.