Bottombar: Select tab within fragment

Created on 4 May 2016 · 8Comments · Source: roughike/BottomBar

First of all, awesome library. I am just curious, is it possible to select specific tab from a fragment? I have 5 different fragments, and i need to update my activity to see changes. If i do so, i need to go to the previous tab. This is bad for the end user, cause he lands on the first tab.

How could i attach the BottomBar within fragment and then select tab like this:
mBottomBar.selectTabAtPosition(3, false);
Thanks a lot! 👍

Source

mag2007

Most helpful comment

@mag2007, Sure. So in your MainActivity where you define BottomBar, make it public static like,

public class MainActivity extends Activity {
...
public static BottomBar mBottomBar;
@Override
   protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        whateverYouWantDone();
    }
    ...
}

And then in your fragment you can access it using MainActivity.mBottomBar

public class FragmentA extends Fragment {
    ...
    void doSomeOperationWithBottomBar(){
    MainActivity.mBottomBar.selectTabAtPosition(3, false); //Since mBottomBar is static, you can get it's reference in any class
    }
    ...
}

PsyGik on 7 May 2016

👍2

All 8 comments

How could i attach the BottomBar within fragment

See #183

PsyGik on 5 May 2016

@PsyGik thanks, but i am not sure, if it is the right thing. I have an activity, where my BottomBar is. My bottombar host 5 fragments - 5 tabs. Now i want to get the selectTabAtPosition inside the fragment for BottomBar, that is attached on activity. Do i need to create custom layout for this? Because i have only menu for the BottomBar.

mag2007 on 5 May 2016

@mag2007, the simplest solution is make the BottomBar static and then reference it from any of your Fragments. That way you can write YourActivity.mBottomBar.selectTabAtPosition(3, false);

If you want a more sophisticated solution, you can use an Interface to communicate between the Activity and Fragments.

PsyGik on 5 May 2016

@PsyGik can you please explain me, how to use it static, (simple answer would be enough)? ReadMe says, it can't be used in xml file. Thanks!

mag2007 on 6 May 2016

@mag2007, Sure. So in your MainActivity where you define BottomBar, make it public static like,

public class MainActivity extends Activity {
...
public static BottomBar mBottomBar;
@Override
   protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        whateverYouWantDone();
    }
    ...
}

And then in your fragment you can access it using MainActivity.mBottomBar

public class FragmentA extends Fragment {
    ...
    void doSomeOperationWithBottomBar(){
    MainActivity.mBottomBar.selectTabAtPosition(3, false); //Since mBottomBar is static, you can get it's reference in any class
    }
    ...
}

PsyGik on 7 May 2016

👍2

Worked like a charm! Thanks! Was thinking to complicated...

mag2007 on 7 May 2016

Bottom Bar from roughike can be used fragment like TabLayout?

ziterz on 18 Sep 2016

@mag2007 @PsyGik i would TOTALLY advice AGAINST this approach, you should not be depending in things like this to be inside static variables, also because you are making this static this means that the Context and all the things attached to it will be kept alive FOR EVER. Also if that wasn't enough if your activity were to appear more than one time, the latest one will override the first one and then you get into a weird state that will create very hard to debug problems. please DON'T DO THIS, and read all the android best practices in the developer documentation.