How to set a Fragment tag by code?
AndroidAndroid 3.0-HoneycombAndroid FragmentsAndroid Problem Overview
I haven't found something like setTag(String tagName)
method in the Fragment
class. The only way to set a Fragment
tag that I have found is by doing a FragmentTransaction
and passing a tag name as parameter.
Is this the only way to explicitly set a Fragment
tag by code?
Android Solutions
Solution 1 - Android
Yes. So the only way is at transaction time, e.g. using add
, replace
, or as part of the layout.
I determined this through an examination of the compatibility sources as I briefly looked for similar at some point in the past.
Solution 2 - Android
You can set tag to fragment in this way:
Fragment fragmentA = new FragmentA();
getFragmentManager().beginTransaction()
.replace(R.id.MainFrameLayout,fragmentA,"YOUR_TARGET_FRAGMENT_TAG")
.addToBackStack("YOUR_SOURCE_FRAGMENT_TAG").commit();
Solution 3 - Android
You can provide a tag inside your activity layout xml file.
Supply the android:tag attribute
with a unique string.
Just as you would assign an id in a layout xml.
android:tag="unique_tag"
Solution 4 - Android
You can also get all fragments like this:
For v4 fragmets
List<Fragment> allFragments = getSupportFragmentManager().getFragments();
For app.fragment
List<Fragment> allFragments = getFragmentManager().getFragments();
Solution 5 - Android
This is the best way I have found :
public class MainActivity extends AppCompatActivity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (savedInstanceState == null) {
// Let's first dynamically add a fragment into a frame container
getSupportFragmentManager().beginTransaction().
replace(R.id.flContainer, new DemoFragment(), "SOMETAG").
commit();
// Now later we can lookup the fragment by tag
DemoFragment fragmentDemo = (DemoFragment)
getSupportFragmentManager().findFragmentByTag("SOMETAG");
}
}
}
Solution 6 - Android
Nowadays there's a simpler way to achieve this if you are using a DialogFragment
(not a Fragment
):
val yourDialogFragment = YourDialogFragment()
yourDialogFragment.show(
activity.supportFragmentManager,
"YOUR_TAG_FRAGMENT"
)
Under the hood, the show()
method does create a FragmentTransaction
and adds the tag by using the add()
method. But it's much more convenient to use the show()
method in my opinion.
You could shorten it for Fragment
too, by using a Kotlin Extension :)
Solution 7 - Android
I know it's been 6 years ago but if anyone is facing the same problem do like I've done:
Create a custom Fragment
Class with a tag field:
public class MyFragment extends Fragment {
private String _myTag;
public void setMyTag(String value)
{
if("".equals(value))
return;
_myTag = value;
}
//other code goes here
}
Before adding the fragment to the sectionPagerAdapter
set the tag just like that:
MyFragment mfrag= new MyFragment();
mfrag.setMyTag("TAG_GOES_HERE");
sectionPagerAdapter.AddFragment(mfrag);
Solution 8 - Android
You can add the tag as a property for the Fragment
arguments. It will be automatically restored if the fragment is destroyed and then recreated by the OS.
Example:-
final Bundle args = new Bundle();
args.putString("TAG", "my tag");
fragment.setArguments(args);