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Android

Posted by Richard Luick
Richard Luick
10,955 Points

Action Bar Up Button as the Back Button

I am playing around with the Ribbit app and came across this navigation scenario which I will explain using three activities: A, B, and C. With activity A being the parent to both B and C.

From activity A, you can navigate to both activity B and C:

A -> B

A -> C (Scenario 1)

However, you can also get to activity C through Activity B:

A -> B -> C (Scenario 2)

In both scenarios, hitting the "up" button will return you to the parent activity A (which is defined in the manifest). This is okay for Scenario 1, however, in Scenario 2, I would like clicking the up button to act similar to the back button and bring you back to activity B. Anyone have any insight on how to adjust the up button in scenarios like this? Thanks,

1 Answer

Greg Hesp
Greg Hesp
1,808 Points
Greg Hesp
Greg Hesp
1,808 Points

The way it is working, is the correct way it should work, and it should remain like that to allow consistency between your app and the android system.

Take a look here: http://developer.android.com/design/patterns/navigation.html

Essentially, the back button is a chronological button which takes you back to the previous screen, but the Up button takes you back to the parent.

An example of this would be: You open Gmail and then a message. In both cases, back and up would do the same thing.

However, lets say in the email, there was a link to Google Maps. If you click the link to Google Maps then it would load the Maps application. To get back to the Gmail message, you would use the back button.

By adding the back functionality to the up button, you are essentially removing a "shortcut" that is consistent across the operating system

Richard Luick
Richard Luick
10,955 Points

Okay, I understand the difference between the two and how they are both supposed to work but I am just curious if it is possible to alter how the up button functions.

For example, in a given app, you may be able use the menu bar to access the "Settings" from a handful of different activities with only one of them technically being the parent. However, it would make sense if (at least to me) if hitting the up (or back) button in a certain circumstance could bring you back to the page you were on when you clicked on the "Settings" tab. Or is it just convention to only have access to the "setting" bar from a single parent activity?