سلام وقت بخیر 

جزییاتی از پروژه رو قرار نداید تا بررسی کنم 

اما در هر حال این کلاس ObservableScrollView هست و میتونید با کد خودتون تطبیق بدید که کدتون مشکلی نداشته باشد.

/*
 * Copyright 2014 Soichiro Kashima
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package ir.udmx.nikestore.view.scroll;
import android.content.Context;
import android.os.Parcel;
import android.os.Parcelable;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ScrollView;
import androidx.core.widget.NestedScrollView;
import java.util.ArrayList;
import java.util.List;
/**
 * ScrollView that its scroll position can be observed.
 */
public class ObservableScrollView extends NestedScrollView implements Scrollable {
    // Fields that should be saved onSaveInstanceState
    private int mPrevScrollY;
    private int mScrollY;
    // Fields that don't need to be saved onSaveInstanceState
    private ObservableScrollViewCallbacks mCallbacks;
    private List<ObservableScrollViewCallbacks> mCallbackCollection;
    private ScrollState mScrollState;
    private boolean mFirstScroll;
    private boolean mDragging;
    private boolean mIntercepted;
    private MotionEvent mPrevMoveEvent;
    private ViewGroup mTouchInterceptionViewGroup;
    public ObservableScrollView(Context context) {
        super(context);
    }
    public ObservableScrollView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }
    public ObservableScrollView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }
    @Override
    public void onRestoreInstanceState(Parcelable state) {
        SavedState ss = (SavedState) state;
        mPrevScrollY = ss.prevScrollY;
        mScrollY = ss.scrollY;
        super.onRestoreInstanceState(ss.getSuperState());
    }
    @Override
    public Parcelable onSaveInstanceState() {
        Parcelable superState = super.onSaveInstanceState();
        SavedState ss = new SavedState(superState);
        ss.prevScrollY = mPrevScrollY;
        ss.scrollY = mScrollY;
        return ss;
    }
    @Override
    protected void onScrollChanged(int l, int t, int oldl, int oldt) {
        super.onScrollChanged(l, t, oldl, oldt);
        if (hasNoCallbacks()) {
            return;
        }
        mScrollY = t;
        dispatchOnScrollChanged(t, mFirstScroll, mDragging);
        if (mFirstScroll) {
            mFirstScroll = false;
        }
        if (mPrevScrollY < t) {
            mScrollState = ScrollState.UP;
        } else if (t < mPrevScrollY) {
            mScrollState = ScrollState.DOWN;
            //} else {
            // Keep previous state while dragging.
            // Never makes it STOP even if scrollY not changed.
            // Before Android 4.4, onTouchEvent calls onScrollChanged directly for ACTION_MOVE,
            // which makes mScrollState always STOP when onUpOrCancelMotionEvent is called.
            // STOP state is now meaningless for ScrollView.
        }
        mPrevScrollY = t;
    }
    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        if (hasNoCallbacks()) {
            return super.onInterceptTouchEvent(ev);
        }
        switch (ev.getActionMasked()) {
            case MotionEvent.ACTION_DOWN:
                // Whether or not motion events are consumed by children,
                // flag initializations which are related to ACTION_DOWN events should be executed.
                // Because if the ACTION_DOWN is consumed by children and only ACTION_MOVEs are
                // passed to parent (this view), the flags will be invalid.
                // Also, applications might implement initialization codes to onDownMotionEvent,
                // so call it here.
                mFirstScroll = mDragging = true;
                dispatchOnDownMotionEvent();
                break;
        }
        return super.onInterceptTouchEvent(ev);
    }
    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        if (hasNoCallbacks()) {
            return super.onTouchEvent(ev);
        }
        switch (ev.getActionMasked()) {
            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_CANCEL:
                mIntercepted = false;
                mDragging = false;
                dispatchOnUpOrCancelMotionEvent(mScrollState);
                break;
            case MotionEvent.ACTION_MOVE:
                if (mPrevMoveEvent == null) {
                    mPrevMoveEvent = ev;
                }
                float diffY = ev.getY() - mPrevMoveEvent.getY();
                mPrevMoveEvent = MotionEvent.obtainNoHistory(ev);
                if (getCurrentScrollY() - diffY <= 0) {
                    // Can't scroll anymore.
                    if (mIntercepted) {
                        // Already dispatched ACTION_DOWN event to parents, so stop here.
                        return false;
                    }
                    // Apps can set the interception target other than the direct parent.
                    final ViewGroup parent;
                    if (mTouchInterceptionViewGroup == null) {
                        parent = (ViewGroup) getParent();
                    } else {
                        parent = mTouchInterceptionViewGroup;
                    }
                    // Get offset to parents. If the parent is not the direct parent,
                    // we should aggregate offsets from all of the parents.
                    float offsetX = 0;
                    float offsetY = 0;
                    for (View v = this; v != null && v != parent; v = (View) v.getParent()) {
                        offsetX += v.getLeft() - v.getScrollX();
                        offsetY += v.getTop() - v.getScrollY();
                    }
                    final MotionEvent event = MotionEvent.obtainNoHistory(ev);
                    event.offsetLocation(offsetX, offsetY);
                    if (parent.onInterceptTouchEvent(event)) {
                        mIntercepted = true;
                        // If the parent wants to intercept ACTION_MOVE events,
                        // we pass ACTION_DOWN event to the parent
                        // as if these touch events just have began now.
                        event.setAction(MotionEvent.ACTION_DOWN);
                        // Return this onTouchEvent() first and set ACTION_DOWN event for parent
                        // to the queue, to keep events sequence.
                        post(new Runnable() {
                            @Override
                            public void run() {
                                parent.dispatchTouchEvent(event);
                            }
                        });
                        return false;
                    }
                    // Even when this can't be scrolled anymore,
                    // simply returning false here may cause subView's click,
                    // so delegate it to super.
                    return super.onTouchEvent(ev);
                }
                break;
        }
        return super.onTouchEvent(ev);
    }
    @Override
    public void setScrollViewCallbacks(ObservableScrollViewCallbacks listener) {
        mCallbacks = listener;
    }
    @Override
    public void addScrollViewCallbacks(ObservableScrollViewCallbacks listener) {
        if (mCallbackCollection == null) {
            mCallbackCollection = new ArrayList<>();
        }
        mCallbackCollection.add(listener);
    }
    @Override
    public void removeScrollViewCallbacks(ObservableScrollViewCallbacks listener) {
        if (mCallbackCollection != null) {
            mCallbackCollection.remove(listener);
        }
    }
    @Override
    public void clearScrollViewCallbacks() {
        if (mCallbackCollection != null) {
            mCallbackCollection.clear();
        }
    }
    @Override
    public void setTouchInterceptionViewGroup(ViewGroup viewGroup) {
        mTouchInterceptionViewGroup = viewGroup;
    }
    @Override
    public void scrollVerticallyTo(int y) {
        scrollTo(0, y);
    }
    @Override
    public int getCurrentScrollY() {
        return mScrollY;
    }
    private void dispatchOnDownMotionEvent() {
        if (mCallbacks != null) {
            mCallbacks.onDownMotionEvent();
        }
        if (mCallbackCollection != null) {
            for (int i = 0; i < mCallbackCollection.size(); i++) {
                ObservableScrollViewCallbacks callbacks = mCallbackCollection.get(i);
                callbacks.onDownMotionEvent();
            }
        }
    }
    private void dispatchOnScrollChanged(int scrollY, boolean firstScroll, boolean dragging) {
        if (mCallbacks != null) {
            mCallbacks.onScrollChanged(scrollY, firstScroll, dragging);
        }
        if (mCallbackCollection != null) {
            for (int i = 0; i < mCallbackCollection.size(); i++) {
                ObservableScrollViewCallbacks callbacks = mCallbackCollection.get(i);
                callbacks.onScrollChanged(scrollY, firstScroll, dragging);
            }
        }
    }
    private void dispatchOnUpOrCancelMotionEvent(ScrollState scrollState) {
        if (mCallbacks != null) {
            mCallbacks.onUpOrCancelMotionEvent(scrollState);
        }
        if (mCallbackCollection != null) {
            for (int i = 0; i < mCallbackCollection.size(); i++) {
                ObservableScrollViewCallbacks callbacks = mCallbackCollection.get(i);
                callbacks.onUpOrCancelMotionEvent(scrollState);
            }
        }
    }
    private boolean hasNoCallbacks() {
        return mCallbacks == null && mCallbackCollection == null;
    }
    static class SavedState extends BaseSavedState {
        int prevScrollY;
        int scrollY;
        /**
         * Called by onSaveInstanceState.
         */
        SavedState(Parcelable superState) {
            super(superState);
        }
        /**
         * Called by CREATOR.
         */
        private SavedState(Parcel in) {
            super(in);
            prevScrollY = in.readInt();
            scrollY = in.readInt();
        }
        @Override
        public void writeToParcel(Parcel out, int flags) {
            super.writeToParcel(out, flags);
            out.writeInt(prevScrollY);
            out.writeInt(scrollY);
        }
        public static final Creator<SavedState> CREATOR
            = new Creator<SavedState>() {
            @Override
            public SavedState createFromParcel(Parcel in) {
                return new SavedState(in);
            }
            @Override
            public SavedState[] newArray(int size) {
                return new SavedState[size];
            }
        };
    }
}

سلام درود 

من هم به این مشکل خوردم و کلاس ObservableScrollView بررسی کردم ولی مشکل در این کلاس نیست . اروری هم که میده به این شرح است

Class not found when unmarshalling: android.core.widget.NestedScrollView$SavedState

آقای یاسری شما به حل این مشکل رسیدین ؟

مشکل حل شد چیز خاصی نبود باید در AuthViewModel در فانکشن login هم پروگرس بار به همان صورتی که در فانکشن signUp مقدار دهی میشه انجام بشه

progressBarLiveData.postValue(false)