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Android Build a Simple Android App (retired 2014) Getting Started with Android Initial Layout

Akshay Shivpuri
Akshay Shivpuri
2,917 Points
Posted by Akshay Shivpuri
Akshay Shivpuri
2,917 Points

Error in mainactivity.java after deleting framelayout.xml

Receiving error in this line

if (savedInstanceState == null) {
            getSupportFragmentManager().beginTransaction()
                    .add(R.id.container, new PlaceholderFragment()).commit();
        }

Error states

Multiple markers at this line
    - container cannot be resolved or is not a field
    - The method add(Fragment, String) in the type FragmentTransaction is not applicable for the arguments (Fragment, 
     MainActivity.PlaceholderFragment)

1 Answer

J Andrew Scott
J Andrew Scott
30,626 Points
J Andrew Scott
J Andrew Scott
30,626 Points

When you modify (or add/delete) layout files, your R class gets regenerated. Chances are R.id.container no longer exists. Your current layout needs to have an element in your current layout with the property android:id="@+id/container"