How to set Content In layout through Custom Component?

Vaadin 6 / 7 / 8
1

Hello everyone,

I know, Theme isn’t good enough to begin with a problem. So, here’s some preface:

I have Completed a multiple layout screen. ATM, I’m writting a CustomComponent which has some controls (Buttons).
everything goes fine ,when i attach custom component using this:

VerticalLayout menuBar = new VerticalLayout();
menuBar.addComponent(MyFirstCustomComponent);

Here’s the thing … clicking on MyFirstCustomComonent’s buttons it should change contents in annother layout like:

annotherLayout.setContent(new PageB());

But i can’t reach it through CustomComponent.

Question is: How could i get annother Layout?

Cheers

P.S Sorry, for my bad English.

2

Simplest solution would be just to pass the instance of the other layout to the customcomponent e.g. in the Constructor.
If that is not possible you could also create a variable in the UI - Singleton that you can staticly reach from pretty much any point of your application. So this way you can set the instance something like MyVaadinUI.get().anotherlayout = …
and reach it with MyVaadinUI.get().anotherlayout.setContent… though the first option is preferred for such a simple case.
As this is more of a general Java Problem you will probably get a lot of information scattered around the web when googling for something like “access variable in other class” or somthing along those lines.

3

Just as an addition to Marius’ answer (which are both correct), in more complex cases you might want to take a look at event buses for this type of communication. There is a lot of info about them online too. With Vaadin, you can use e.g. the blackboard addon, or if you are using CDI, you can use CDI Events.