Issues with Android's hardware back button with Tabs

Version

Tell us which versions you are using:

• react-native-router-flux 4.0.0-beta.27 (v3 is not supported)
• react-native 0.54.0

Expected behaviour

When navigating to a Scene outside of Tabs from within tabs and then pressing the hardware back button, you should then be navigated back to the previous scene within tabs.

Actual behaviour

When navigating to a scene outside of tabs from within tabs and then pressing the hardware back button it navigates you to the last visited page outside of tabs. Ignoring the scene within tabs which was previously visited.

Steps to reproduce

For non-obvious bugs, please fork this component, modify Example project to reproduce your issue and include link here.

1. Create a similar router to the example below
2. Navigate to page_2
3. Then navigate to page_3
4. Press hardware back button
5. You will end up on page_1

Minimal example router:

<Router>
    <Drawer key={'root'} contentComponent={...}>
        <Scene key={'page_1'} initial={true} component={...}/>
        <Scene key={'page_3'} component={...}/>

        <Tabs>
            <Scene key={'page_2'} component={...}/>
        </Tabs>
    </Drawer>
</Router>

Edit: Now seeing the same issues on react-native-router-flux 4.0.2

[daviscabral]

Check the Example, it’s working there 👍

[daviscabral]

I believe a custom reducer also can make it work without needing to change the lib. I am inclined to close this issue since the lib is flexible enough to allow a proper fix. What do you think?