androidandroid-recyclerviewoverscroll

How do I detect OverScroll in android RecyclerView?


I have tried to overwrite onOverScrolled() but it is not triggered:

public class MyRecyclerView extends RecyclerView {
    public MyRecyclerView(@NonNull Context context) {
        super(context);
    }

    public MyRecyclerView(@NonNull Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
    }

    public MyRecyclerView(@NonNull Context context, @Nullable AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    @Override
    protected void onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY) {
        super.onOverScrolled(scrollX, scrollY, clampedX, clampedY);
        Toast.makeText(getContext(), "overScrolled", Toast.LENGTH_SHORT).show();
    }
}

My RecyclerView has recyclerView.setOverScrollMode(View.OVER_SCROLL_ALWAYS);


Solution

  • Try this to find bottom overscroll and top overscroll

    Find bottom overscroll and top overscroll Using LayoutManager

    import android.os.Bundle;
    import java.util.ArrayList;
    import androidx.appcompat.app.AppCompatActivity;
    import androidx.recyclerview.widget.LinearLayoutManager;
    import androidx.recyclerview.widget.RecyclerView;
    
    public class MainActivity extends AppCompatActivity {
    
        RecyclerView myRecyclerView;
        ArrayList<String> arrayList = new ArrayList<>();
        DataAdapter adapter;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
    
            myRecyclerView = findViewById(R.id.myRecyclerView);
    
            LinearLayoutManager linearLayoutManager= new LinearLayoutManager(this){
                @Override
                public int scrollVerticallyBy ( int dx, RecyclerView.Recycler recycler, RecyclerView.State state ) {
                    int scrollRange = super.scrollVerticallyBy(dx, recycler, state);
                    int overScroll = dx - scrollRange;
                    if (overScroll > 0) {
                        Utils.printLog("NILU_PILU :-> BOTTOM OVERSCROLL");
                    } else if (overScroll < 0) {
                        Utils.printLog("NILU_PILU :-> TOP OVERSCROLL");
                    }
                    return scrollRange;
                }
            };
            myRecyclerView.setLayoutManager(linearLayoutManager);
            myRecyclerView.setHasFixedSize(true);
    
            addDataToList();
    
            adapter = new DataAdapter(this, arrayList);
            myRecyclerView.setAdapter(adapter);
    
        }
    
        private void addDataToList() {
            for (int i = 0; i < 50; i++) {
                arrayList.add("NILU_PILU :-> " + i);
            }
        }
    
    }
    

    Find bottom overscroll Using RecyclerView.addOnScrollListener()

     myRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override
            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                super.onScrolled(recyclerView, dx, dy);
    
                if (dy > 0) {
    
                    int pos = linearLayoutManager.findLastVisibleItemPosition();
                    int numItems = myRecyclerView.getAdapter().getItemCount();
    
                    if (pos >= numItems - 1 ) {
                        Utils.printLog("NILU_PILU :-> BOTTOM OVERSCROLL");
                    }
                }
            }
        });