Java Code Examples for androidx.recyclerview.widget.RecyclerView#removeOnScrollListener()

@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
    super.onScrollStateChanged(recyclerView, newState);

    if (newState == RecyclerView.SCROLL_STATE_IDLE) {
        recyclerView.removeOnScrollListener(this);
        mIsMoved = false;
        mCurrentRVTouched = null;
        if (recyclerView == mCellRecyclerView) {
            Log.d(LOG_TAG, "mCellRecyclerView scroll listener removed from " +
                    "onScrollStateChanged");
        } else if (recyclerView == mRowHeaderRecyclerView) {
            Log.d(LOG_TAG, "mRowHeaderRecyclerView scroll listener removed from " +
                    "onScrollStateChanged");
        }
    }
}
 

@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
    super.onScrollStateChanged(recyclerView, newState);

    if (newState == RecyclerView.SCROLL_STATE_IDLE) {
        // Renew the scroll position and its offset
        renewScrollPosition(recyclerView);

        recyclerView.removeOnScrollListener(this);
        Log.d(LOG_TAG, "Scroll listener has been removed to " + recyclerView.getId() + " at "
                + "onScrollStateChanged");
        mIsMoved = false;

        // When a user scrolls horizontally, VerticalRecyclerView add vertical scroll
        // listener because of touching process.However, mVerticalRecyclerViewListener
        // doesn't know anything about it. So, it is necessary to remove the last touched
        // recyclerView which uses the mVerticalRecyclerViewListener.
        boolean isNeeded = mLastTouchedRecyclerView != mColumnHeaderRecyclerViews.get(0);
        mVerticalRecyclerViewListener.removeLastTouchedRecyclerViewScrollListener(isNeeded);
    }
}
 

/**
 * Set edge effect or glow color for recycler view.
 *
 * @param recyclerView The recycler view to set the edge effect color.
 * @param color The edge effect color to be set.
 * @param scrollListener Scroll listener to set color on over scroll.
 */
public static void setEdgeEffectColor(@Nullable RecyclerView recyclerView,
        final @ColorInt int color, @Nullable RecyclerView.OnScrollListener scrollListener) {
    if (recyclerView == null) {
        return;
    }

    if (scrollListener == null) {
        scrollListener =
                new RecyclerView.OnScrollListener() {
                    @Override
                    public void onScrollStateChanged(@NonNull RecyclerView recyclerView,
                            int newState) {
                        super.onScrollStateChanged(recyclerView, newState);

                        setEdgeEffectColor(recyclerView, color);
                    }
                };

        recyclerView.removeOnScrollListener(scrollListener);
        recyclerView.addOnScrollListener(scrollListener);
    }

    setEdgeEffectColor(recyclerView, color);
}
 

@Override
public void onScrollStateChanged(@NonNull RecyclerView recyclerView, int newState) {
    super.onScrollStateChanged(recyclerView, newState);

    if (newState == RecyclerView.SCROLL_STATE_IDLE) {
        // Renew the scroll position and its offset
        renewScrollPosition(recyclerView);

        recyclerView.removeOnScrollListener(this);
        Log.d(LOG_TAG, "Scroll listener has been removed to " + recyclerView.getId() + " at "
                + "onScrollStateChanged");
        mIsMoved = false;

        // When a user scrolls horizontally, VerticalRecyclerView add vertical scroll
        // listener because of touching process.However, mVerticalRecyclerViewListener
        // doesn't know anything about it. So, it is necessary to remove the last touched
        // recyclerView which uses the mVerticalRecyclerViewListener.
        boolean isNeeded = mLastTouchedRecyclerView != mColumnHeaderRecyclerView;
        mVerticalRecyclerViewListener.removeLastTouchedRecyclerViewScrollListener(isNeeded);
    }
}
 

@Override
public void onScrollStateChanged(@NonNull RecyclerView recyclerView, int newState) {
    super.onScrollStateChanged(recyclerView, newState);

    if (newState == RecyclerView.SCROLL_STATE_IDLE) {
        recyclerView.removeOnScrollListener(this);
        mIsMoved = false;
        mCurrentRVTouched = null;
        if (recyclerView == mCellRecyclerView) {
            Log.d(LOG_TAG, "mCellRecyclerView scroll listener removed from " +
                    "onScrollStateChanged");
        } else if (recyclerView == mRowHeaderRecyclerView) {
            Log.d(LOG_TAG, "mRowHeaderRecyclerView scroll listener removed from " +
                    "onScrollStateChanged");
        }
    }
}
 

public void attachToRecyclerView(@NonNull RecyclerView recyclerView,
        @NonNull SnapHelper snapHelper) {
    mRecyclerView = recyclerView;
    mSnapHelper = snapHelper;
    mLastPosition = -1;
    createIndicators();
    recyclerView.removeOnScrollListener(mInternalOnScrollListener);
    recyclerView.addOnScrollListener(mInternalOnScrollListener);
}
 

@Override
public void detach(Context context, RecyclerView recyclerView) {
    super.detach(context, recyclerView);
    recyclerView.removeOnScrollListener(mScrollListener);
    mColors.recycle();
    mItemTouchHelper.attachToRecyclerView(null);
}
 

private void toggleAutoMarkAsViewed(RecyclerView recyclerView) {
    if (Preferences.autoMarkAsViewed(recyclerView.getContext())) {
        recyclerView.addOnScrollListener(mAutoViewScrollListener);
    } else {
        recyclerView.removeOnScrollListener(mAutoViewScrollListener);
    }
}
 

@Override public void onDestroyView() {
  final RecyclerView recyclerView = getRecyclerView();
  if (recyclerView != null && endlessRecyclerOnScrollListener != null) {
    recyclerView.removeOnScrollListener(endlessRecyclerOnScrollListener);
  }
  endlessRecyclerOnScrollListener = null;
  header = null;
  collapsingToolbarLayout = null;
  super.onDestroyView();
}
 

/**
 * Detach the tracker
 *
 * @param recyclerView The recycler view that the EpoxyController has its adapter added to.
 */
public void detach(@NonNull RecyclerView recyclerView) {
  recyclerView.removeOnScrollListener(this.listener);
  recyclerView.removeOnLayoutChangeListener(this.listener);
  recyclerView.removeOnChildAttachStateChangeListener(this.listener);
  setTracker(recyclerView, null);
  attachedRecyclerView = null;
}
 

@Override
public void onDetachedFromRecyclerView(RecyclerView recyclerView) {
    if (moreLoader != null) {
        recyclerView.removeOnScrollListener(moreLoader);
    }
    super.onDetachedFromRecyclerView(recyclerView);
}
 

@Override
protected boolean detach(RecyclerView recyclerView) {
    if (recyclerView != null) {
        recyclerView.removeOnScrollListener(this);
        clearStickyView();
    }

    return true;
}
 

@Override
public boolean onInterceptTouchEvent(@NonNull RecyclerView rv, @NonNull MotionEvent e) {

    // Prevent multitouch, once we start to listen with a RV,
    // we ignore any other RV until the touch is released (UP)
    if ((mCurrentRVTouched != null && rv != mCurrentRVTouched)) {
        return true;
    }

    // If scroll direction is not Vertical, then ignore and reset last RV touched
    if (!verticalDirection(e)) {
        mCurrentRVTouched = null;
        return false;
    }

    if (e.getAction() == MotionEvent.ACTION_DOWN) {
        mCurrentRVTouched = rv;
        if (rv.getScrollState() == RecyclerView.SCROLL_STATE_IDLE) {

            if (mLastTouchedRecyclerView != null && rv != mLastTouchedRecyclerView) {
                removeLastTouchedRecyclerViewScrollListener(false);
            }
            mYPosition = ((CellRecyclerView) rv).getScrolledY();
            rv.addOnScrollListener(this);

            if (rv == mCellRecyclerView) {
                Log.d(LOG_TAG, "mCellRecyclerView scroll listener added");
            } else if (rv == mRowHeaderRecyclerView) {
                Log.d(LOG_TAG, "mRowHeaderRecyclerView scroll listener added");
            }

            // Refresh the value;
            mIsMoved = false;
        }
    } else if (e.getAction() == MotionEvent.ACTION_MOVE) {
        mCurrentRVTouched = rv;
        // Why does it matter ?
        // user scroll any recyclerView like brushing, at that time, ACTION_UP will be
        // triggered
        // before scrolling. So, we need to store whether it moved or not.
        mIsMoved = true;
    } else if (e.getAction() == MotionEvent.ACTION_UP) {
        mCurrentRVTouched = null;
        int nScrollY = ((CellRecyclerView) rv).getScrolledY();

        // TODO: Even if moved value is true and it may not scroll. This should be fixed.
        // TODO: The scenario is scroll lightly center RecyclerView vertically.
        // TODO: Below if condition may be changed later.

        // Is it just touched without scrolling then remove the listener
        if (mYPosition == nScrollY && !mIsMoved && rv.getScrollState() == RecyclerView
                .SCROLL_STATE_IDLE) {
            rv.removeOnScrollListener(this);

            if (rv == mCellRecyclerView) {
                Log.d(LOG_TAG, "mCellRecyclerView scroll listener removed from up ");
            } else if (rv == mRowHeaderRecyclerView) {
                Log.d(LOG_TAG, "mRowHeaderRecyclerView scroll listener removed from up");
            }
        }

        mLastTouchedRecyclerView = rv;

    }

    return false;
}
 

@Override
public boolean onInterceptTouchEvent(@NonNull RecyclerView rv, @NonNull MotionEvent e) {

    // Prevent multitouch, once we start to listen with a RV,
    // we ignore any other RV until the touch is released (UP)
    if (mCurrentRVTouched != null && rv != mCurrentRVTouched) {
        return true;
    }

    if (e.getAction() == MotionEvent.ACTION_DOWN) {
        mCurrentRVTouched = rv;
        if (rv.getScrollState() == RecyclerView.SCROLL_STATE_IDLE) {

            if (mLastTouchedRecyclerView != null && rv != mLastTouchedRecyclerView) {
                if (mLastTouchedRecyclerView == mColumnHeaderRecyclerView) {
                    mColumnHeaderRecyclerView.removeOnScrollListener(this);
                    mColumnHeaderRecyclerView.stopScroll();
                    Log.d(LOG_TAG, "Scroll listener  has been removed to " +
                            "mColumnHeaderRecyclerView at last touch control");
                } else {
                    int lastTouchedIndex = getIndex(mLastTouchedRecyclerView);

                    // Control whether the last touched recyclerView is still attached or not
                    if (lastTouchedIndex >= 0 && lastTouchedIndex < mCellLayoutManager
                            .getChildCount()) {
                        // Control the scroll listener is already removed. For instance; if user
                        // scroll the parent recyclerView vertically, at that time,
                        // ACTION_CANCEL
                        // will be triggered that removes the scroll listener of the last
                        // touched
                        // recyclerView.
                        if (!((CellRecyclerView) mLastTouchedRecyclerView)
                                .isHorizontalScrollListenerRemoved()) {
                            // Remove scroll listener of the last touched recyclerView
                            // Because user touched another recyclerView before the last one get
                            // SCROLL_STATE_IDLE state that removes the scroll listener
                            ((RecyclerView) mCellLayoutManager.getChildAt(lastTouchedIndex))
                                    .removeOnScrollListener(this);

                            Log.d(LOG_TAG, "Scroll listener  has been removed to " +
                                    mLastTouchedRecyclerView.getId() + " CellRecyclerView " +
                                    "at last touch control");

                            // the last one scroll must be stopped to be sync with others
                            ((RecyclerView) mCellLayoutManager.getChildAt(lastTouchedIndex))
                                    .stopScroll();
                        }
                    }
                }
            }

            mXPosition = ((CellRecyclerView) rv).getScrolledX();
            rv.addOnScrollListener(this);
            Log.d(LOG_TAG, "Scroll listener  has been added to " + rv.getId() + " at action "
                    + "down");
        }
    } else if (e.getAction() == MotionEvent.ACTION_MOVE) {
        mCurrentRVTouched = rv;
        // Why does it matter ?
        // user scroll any recyclerView like brushing, at that time, ACTION_UP will be
        // triggered
        // before scrolling. So, we need to store whether it moved or not.
        mIsMoved = true;
    } else if (e.getAction() == MotionEvent.ACTION_UP) {
        mCurrentRVTouched = null;
        int nScrollX = ((CellRecyclerView) rv).getScrolledX();
        // Is it just touched without scrolling then remove the listener
        if (mXPosition == nScrollX && !mIsMoved) {
            rv.removeOnScrollListener(this);
            Log.d(LOG_TAG, "Scroll listener  has been removed to " + rv.getId() + " at " +
                    "action" + " up");
        }

        mLastTouchedRecyclerView = rv;

    } else if (e.getAction() == MotionEvent.ACTION_CANCEL) {
        // ACTION_CANCEL action will be triggered if users try to scroll vertically
        // For this situation, it doesn't matter whether the x position is changed or not
        // Beside this, even if moved action will be triggered, scroll listener won't
        // triggered on cancel action. So, we need to change state of the mIsMoved value as
        // well.

        // Renew the scroll position and its offset
        renewScrollPosition(rv);

        rv.removeOnScrollListener(this);
        Log.d(LOG_TAG, "Scroll listener  has been removed to " + rv.getId() + " at action " +
                "cancel");

        mIsMoved = false;

        mLastTouchedRecyclerView = rv;

        mCurrentRVTouched = null;
    }

    return false;
}
 

public void onStop(RecyclerView recyclerView) {
    recyclerView.removeOnScrollListener(onScrollListener);
    itemSource.close();
}
 

/**
 * Call from the owning {@link Component}'s onUnmount. This is where the adapter is removed from
 * the {@link RecyclerView}.
 *
 * @param view the {@link RecyclerView} being unmounted.
 */
@UiThread
@Override
public void unmount(RecyclerView view) {
  ThreadUtils.assertMainThread();
  if (mIsSubAdapter) {
    throw new RuntimeException("Can't unmount a RecyclerView in sub adapter mode");
  }

  final LayoutManager layoutManager = mLayoutInfo.getLayoutManager();
  final View firstView = layoutManager.findViewByPosition(mCurrentFirstVisiblePosition);

  if (firstView != null) {
    final boolean reverseLayout = getReverseLayout();

    if (mLayoutInfo.getScrollDirection() == HORIZONTAL) {
      mCurrentOffset =
          reverseLayout
              ? view.getWidth()
                  - layoutManager.getPaddingRight()
                  - layoutManager.getDecoratedRight(firstView)
              : layoutManager.getDecoratedLeft(firstView) - layoutManager.getPaddingLeft();
    } else {
      mCurrentOffset =
          reverseLayout
              ? view.getHeight()
                  - layoutManager.getPaddingBottom()
                  - layoutManager.getDecoratedBottom(firstView)
              : layoutManager.getDecoratedTop(firstView) - layoutManager.getPaddingTop();
    }
  } else {
    mCurrentOffset = 0;
  }

  view.removeOnScrollListener(mViewportManager.getScrollListener());

  unregisterDrawListener(view);
  maybeDispatchDataRendered();

  view.setAdapter(null);
  view.setLayoutManager(null);

  mViewportManager.removeViewportChangedListener(mViewportChangedListener);

  // We might have already unmounted this view when calling mount with a different view. In this
  // case we can just return here.
  if (mMountedView != view) {
    return;
  }

  mMountedView = null;
  if (mStickyHeaderController != null) {
    mStickyHeaderController.reset();
  }

  mLayoutInfo.setRenderInfoCollection(null);
}
 

@Override
public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {

    // Prevent multitouch, once we start to listen with a RV,
    // we ignore any other RV until the touch is released (UP)
    if (mCurrentRVTouched != null && rv != mCurrentRVTouched) {
        return true;
    }

    if (e.getAction() == MotionEvent.ACTION_DOWN) {
        mCurrentRVTouched = rv;
        if (rv.getScrollState() == RecyclerView.SCROLL_STATE_IDLE) {

            if (mLastTouchedRecyclerView != null && rv != mLastTouchedRecyclerView) {
                if (mLastTouchedRecyclerView == mColumnHeaderRecyclerViews) {
                    mColumnHeaderRecyclerViews.get(0).removeOnScrollListener(this);
                    mColumnHeaderRecyclerViews.get(0).stopScroll();
                    Log.d(LOG_TAG, "Scroll listener  has been removed to " +
                            "mColumnHeaderRecyclerView at last touch control");
                } else {
                    int lastTouchedIndex = getIndex(mLastTouchedRecyclerView);

                    // Control whether the last touched recyclerView is still attached or not
                    if (lastTouchedIndex >= 0 && lastTouchedIndex < mCellLayoutManager
                            .getChildCount()) {
                        // Control the scroll listener is already removed. For instance; if user
                        // scroll the parent recyclerView vertically, at that time,
                        // ACTION_CANCEL
                        // will be triggered that removes the scroll listener of the last
                        // touched
                        // recyclerView.
                        if (!((CellRecyclerView) mLastTouchedRecyclerView)
                                .isHorizontalScrollListenerRemoved()) {
                            // Remove scroll listener of the last touched recyclerView
                            // Because user touched another recyclerView before the last one get
                            // SCROLL_STATE_IDLE state that removes the scroll listener
                            ((RecyclerView) mCellLayoutManager.getChildAt(lastTouchedIndex))
                                    .removeOnScrollListener(this);

                            Log.d(LOG_TAG, "Scroll listener  has been removed to " +
                                    mLastTouchedRecyclerView.getId() + " CellRecyclerView " +
                                    "at last touch control");

                            // the last one scroll must be stopped to be sync with others
                            ((RecyclerView) mCellLayoutManager.getChildAt(lastTouchedIndex))
                                    .stopScroll();
                        }
                    }
                }
            }

            mXPosition = ((CellRecyclerView) rv).getScrolledX();
            rv.addOnScrollListener(this);
            Log.d(LOG_TAG, "Scroll listener  has been added to " + rv.getId() + " at action "
                    + "down");
        }
    } else if (e.getAction() == MotionEvent.ACTION_MOVE) {
        mCurrentRVTouched = rv;
        // Why does it matter ?
        // user scroll any recyclerView like brushing, at that time, ACTION_UP will be
        // triggered
        // before scrolling. So, we need to store whether it moved or not.
        mIsMoved = true;
    } else if (e.getAction() == MotionEvent.ACTION_UP) {
        mCurrentRVTouched = null;
        int nScrollX = ((CellRecyclerView) rv).getScrolledX();
        // Is it just touched without scrolling then remove the listener
        if (mXPosition == nScrollX && !mIsMoved) {
            rv.removeOnScrollListener(this);
            Log.d(LOG_TAG, "Scroll listener  has been removed to " + rv.getId() + " at " +
                    "action" + " up");
        }

        mLastTouchedRecyclerView = rv;

    } else if (e.getAction() == MotionEvent.ACTION_CANCEL) {
        // ACTION_CANCEL action will be triggered if users try to scroll vertically
        // For this situation, it doesn't matter whether the x position is changed or not
        // Beside this, even if moved action will be triggered, scroll listener won't
        // triggered on cancel action. So, we need to change state of the mIsMoved value as
        // well.

        // Renew the scroll position and its offset
        renewScrollPosition(rv);

        rv.removeOnScrollListener(this);
        Log.d(LOG_TAG, "Scroll listener  has been removed to " + rv.getId() + " at action " +
                "cancel");

        mIsMoved = false;

        mLastTouchedRecyclerView = rv;

        mCurrentRVTouched = null;
    }

    return false;
}
 

@Override
public void onDetachedFromRecyclerView(RecyclerView recyclerView) {
    super.onDetachedFromRecyclerView(recyclerView);
    recyclerView.removeOnScrollListener(scrollListener);
}
 

@Override
public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {

    // Prevent multitouch, once we start to listen with a RV,
    // we ignore any other RV until the touch is released (UP)
    if((mCurrentRVTouched != null && rv != mCurrentRVTouched)) {
        return true;
    }
        
    // If scroll direction is not Vertical, then ignore and reset last RV touched
    if(!verticalDirection(e)) {
        mCurrentRVTouched = null;
        return false;
    }

    if (e.getAction() == MotionEvent.ACTION_DOWN) {
        mCurrentRVTouched = rv;
        if (rv.getScrollState() == RecyclerView.SCROLL_STATE_IDLE) {

            if (mLastTouchedRecyclerView != null && rv != mLastTouchedRecyclerView) {
                removeLastTouchedRecyclerViewScrollListener(false);
            }
            mYPosition = ((CellRecyclerView) rv).getScrolledY();
            rv.addOnScrollListener(this);

            if (rv == mCellRecyclerView) {
                Log.d(LOG_TAG, "mCellRecyclerView scroll listener added");
            } else if (rv == mRowHeaderRecyclerView) {
                Log.d(LOG_TAG, "mRowHeaderRecyclerView scroll listener added");
            }

            // Refresh the value;
            mIsMoved = false;
        }
    } else if (e.getAction() == MotionEvent.ACTION_MOVE) {
        mCurrentRVTouched = rv;
        // Why does it matter ?
        // user scroll any recyclerView like brushing, at that time, ACTION_UP will be
        // triggered
        // before scrolling. So, we need to store whether it moved or not.
        mIsMoved = true;
    } else if (e.getAction() == MotionEvent.ACTION_UP) {
        mCurrentRVTouched = null;
        int nScrollY = ((CellRecyclerView) rv).getScrolledY();

        // TODO: Even if moved value is true and it may not scroll. This should be fixed.
        // TODO: The scenario is scroll lightly center RecyclerView vertically.
        // TODO: Below if condition may be changed later.

        // Is it just touched without scrolling then remove the listener
        if (mYPosition == nScrollY && !mIsMoved && rv.getScrollState() == RecyclerView
                .SCROLL_STATE_IDLE) {
            rv.removeOnScrollListener(this);

            if (rv == mCellRecyclerView) {
                Log.d(LOG_TAG, "mCellRecyclerView scroll listener removed from up ");
            } else if (rv == mRowHeaderRecyclerView) {
                Log.d(LOG_TAG, "mRowHeaderRecyclerView scroll listener removed from up");
            }
        }

        mLastTouchedRecyclerView = rv;

    }

    return false;
}