Custom back navigation
Back navigation lets users move backwards through the screens they previously visited.
The most common form of back navigation is done through the back button. The stack layout contains a back button by default, also known as the software back button.
RNN handles the back navigation for you, but there are use cases where you might need to override the default behavior of the back navigation. For example, when editing a blog post, you might want to prompt the user about unsaved changes instead of navigating to the previous destination.
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Additional back navigation methods- Android devices include a hardware back button, located at the bottom of the device.
- Android 11 introduced an opt-in gesture navigation system that hides the NavigationBar. When enabled, the hardware back button is replaced with a back gesture performed with a horizontal swipe across the screen.
- The stack layout on iOS supports a back gesture by default. Like the android back gesture, it's performed by swiping across the screen.
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Handling the software back buttonThe software back button is located in the TopBar and is responsible for popping the top most screen in the stack. It's configured in the TopBar options.
To handle the software back button, we must first disable the default behavior which is to pop the top most screen:
Now, when the software back button is pressed, instead of popping the screen RNN will emit a navigationButtonPress event which can be handled in JS.
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Handling the hardware back buttonUnlike the software back button which affects the stack it's part of, the hardware back button isn't bound to a specific layout. Instead, The hardware back button affects the top most layout that responds to back navigation.
When a stack containing more than one child is focused, pressing the hardware back button will pop the stack. When a modal is displayed and the current stack has exactly one child, pressing the hardware back button will dismiss the modal.
To handle the hardware back button, we must first disable the default behavior for the desired action (pop stack or dismiss modal) through options:
Once the default behaviors are disabled, RNN will emit a navigationButtonPress with the RNN.hardwareBackButton
id.
Note
The hardware back button is available on Android only.
Note 2
When gesture navigation is enabled on Android, the back gesture is handled as a hardware back press.
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Disabling the iOS pop gestureThe iOS stack layout can be popped with a swipe gesture. If desired, the swipe gesture can be disabled via options: