How do I check if a field in another activity was filled? [closed]

Each user has its profile that is stored in a XML file linked to a Java class. But not necessarily they access this profile when they use the App, because they may just use the app without editing its …

when I click on the button the app crashes

Here the error: java.lang.IllegalStateException: Could not find method OpenRadio(View) in a parent or ancestor Context for android:onClick attribute defined on view class android.support.v7.widget….

Activity does not have a NavController set on

I basically set up 3 fragments for my bottom navigation view with all linked to activity.xml activity.xml where I put fragment tag.

Activity or Fragment for a SearchView?

I´m doing my final degree project and I have chose to develop and Android app using Firebase Firestore, the idea it´s cool because I´m learning how to program on Android, but on Java. So, I have …

Call method from Fragment in unselected tab

I have an application with tabs. I use ViewPager and TabLayout. In each tab I have a Fragment. When the tab is unselected I want to call a method from the fragment in that tab. If I want to call …

How to prevent activity to restart after changing its orientation

I’m new to android development using KOTLIN, i have activity that contain fragments like the image below (Image 1), the problem is whenever i try to change the orientation from potrait to landscape, …

ViewPager2 not working properly with Fragments and click events

I just wanna know if I’m doing something wrong since I’m kinda new to all this. If there is anything else that you’ll like me to add just let me know. This is the repo branch where I’m trying to …

Cannot find symbol error in android studio

I’m trying to add fragments to a navigation drawer. But I have the error: cannot find symbol class Fragment. I added: import android.support.v4.app.Fragment Also add the fragment object(Fragment …

NavigationView header image

I need to change NavigationView header image from fragment, but i am getting error. Someone can tell me what i am doing wrong?. Thank you for helping))) java.lang.NullPointerException: Attempt to …

Starting a new activity on navigation drawer item click

I know this is a question frequently asked, but after reading the many questions and solutions on stack overflow I am confused. I am confused with regards to Fragments and what is required to start an …