Dynamic Endless RecyclerView - Probleme beim Scrollen

Ich muss folgendes Layout erstellen

Bisher habe ich das Layout erfolgreich erstellt und alle Ansichten ausgefüllt. Ich habe jedoch ein Problem damit, ReyclerView Endless auf dem ersten Fragment zu erstellen.

Consider the RecyclerView hat 10 Elemente beim ersten Laden, jetzt beim Scrollen füge ich weitere 10 Elemente hinzu und so weiter. Die RecyclerView zeigt diese Elemente jedoch nicht an, da ihre Höhe am Ende des 10. Elements festgelegt wird. Ich weiß, dass die Elemente in RecyclerView korrekt geladen sind und wenn ich versuche, mit zwei Fingern auf dem Emulator (GenyMotion) zu scrollen, funktioniert das Scrollen in RecyclerView einwandfrei.

Update: -

Code für das Fragment von RecyclerView -

public class CheckInFragmentRecyclerAdapter extends RecyclerView.Adapter<CheckInFragmentRecyclerAdapter.ViewHolder> {
    final List<StoreNew> stores;

    public CheckInFragmentRecyclerAdapter(final List<StoreNew> stores) {
        this.stores = stores;
    }

    @Override
    public CheckInFragmentRecyclerAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        final View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.child_check_in_fragment, parent, false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(CheckInFragmentRecyclerAdapter.ViewHolder holder, int position) {
        // Setting data
    }


    @Override
    public int getItemCount() {
        return stores.size();
    }

    /**
     * Function to clear existing data from list
     * @param stores StoreNew instance containing store information
     */
    public void update(final List<StoreNew> stores) {
        this.stores.clear();
        this.stores.addAll(stores);
        notifyDataSetChanged();
    }

    /**
     * Function to add more data to list
     * @param stores StoreNew instance containing store information
     */
    public void addNewList(final List<StoreNew> stores) {
        this.stores.addAll(stores);
        notifyDataSetChanged();
    }

    public class ViewHolder extends RecyclerView.ViewHolder {

        public ViewHolder(View itemView) {
            super(itemView);

            // Initializing component
        }
    }
}

Update: -

Layouts für verwendete Bildschirme hinzufügen.

main_screen.xml - Dies ist der Startbildschirm

<android.support.v4.widget.NestedScrollView
        android:id="@+id/scrollView1"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_above="@+id/home_footer"
        android:layout_below="@+id/toolbar"
        android:fillViewport="true">

        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">
            <!-- Sliding Tab for showing images -->
            <com.example.slidingtab.SlidingTabLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="@color/white" />
            <!-- ViewPager for Images -->
            <android.support.v4.view.ViewPager
                android:id="@+id/vpOffers"
                android:layout_width="match_parent"
                android:layout_height="150dp"
                android:layout_marginTop="8dp" />
            <!-- Segmented Control for fragments -->
            <info.hoang8f.android.segmented.SegmentedGroup xmlns:segmentedgroup="http://schemas.android.com/apk/res-auto"
                android:id="@+id/segmented2"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginBottom="15dp"
                android:layout_marginEnd="10dp"
                android:layout_marginLeft="10dp"
                android:layout_marginRight="10dp"
                android:layout_marginStart="10dp"
                android:layout_marginTop="10dp"
                android:orientation="horizontal"
                segmentedgroup:sc_border_width="1dp"
                segmentedgroup:sc_corner_radius="4dp"
                segmentedgroup:sc_tint_color="@color/black">

                <RadioButton
                    android:id="@+id/rbTab1"
                    style="@style/segmented_radio_button"
                    android:layout_width="0dp"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:checked="true"
                    android:textSize="@dimen/normal_text"
                    android:text="@string/check_in" />

                <RadioButton
                    android:id="@+id/rbTab2"
                    style="@style/segmented_radio_button"
                    android:layout_width="0dp"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:textSize="@dimen/normal_text"
                    android:text="@string/upload_bill" />

                <RadioButton
                    android:id="@+id/rbTab3"
                    style="@style/segmented_radio_button"
                    android:layout_width="0dp"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:textSize="@dimen/normal_text"
                    android:text="@string/redeem" />

            </info.hoang8f.android.segmented.SegmentedGroup>

            <!-- Custom wrap content ViewPager containing fragments -->
            <!-- This will make sure that the height of ViewPager is equal to height of Fragment -->
            <com.example.ui.custom.WrapContentHeightViewPager
                android:id="@+id/vpFragments"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginTop="-7dp" />
        </LinearLayout>
    </android.support.v4.widget.NestedScrollView>

WrapContentHeightViewPager.java

public class WrapContentHeightViewPager extends ViewPager {

    private static final String TAG = WrapContentHeightViewPager.class.getSimpleName();
    private int height = 0;
    private int decorHeight = 0;
    private int widthMeasuredSpec;

    private boolean animateHeight;
    private int rightHeight;
    private int leftHeight;
    private int scrollingPosition = -1;
    private boolean enabled;

    public WrapContentHeightViewPager(Context context) {
        super(context);
        init();
    }

    public WrapContentHeightViewPager(Context context, AttributeSet attrs) {
        super(context, attrs);
        this.enabled = true;
        init();
    }

    private void init() {
        addOnPageChangeListener(new OnPageChangeListener() {


            public int state;

            @Override
            public void onPageScrolled(int position, float offset, int positionOffsetPixels) {}

            @Override
            public void onPageSelected(int position) {
                if (state == SCROLL_STATE_IDLE) {
                    height = 0; // measure the selected page in-case it's a change without scrolling
                    Log.d(TAG, "onPageSelected:" + position);
                }
            }

            @Override
            public void onPageScrollStateChanged(int state) {
                this.state = state;
            }
        });
    }


    @Override
    public boolean onTouchEvent(MotionEvent event) {
        return this.enabled && super.onTouchEvent(event);

    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent event) {
        return this.enabled && super.onInterceptTouchEvent(event);

    }

    public void setPagingEnabled(boolean enabled) {
        this.enabled = enabled;
    }

    @Override
    public void setAdapter(PagerAdapter adapter) {
        height = 0; // so we measure the new content in onMeasure
        super.setAdapter(new PagerAdapterWrapper(adapter));
    }

    /**
     * Allows to redraw the view size to wrap the content of the bigger child.
     *
     * @param widthMeasureSpec  with measured
     * @param heightMeasureSpec height measured
     */
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        widthMeasuredSpec = widthMeasureSpec;
        int mode = MeasureSpec.getMode(heightMeasureSpec);

        if (mode == MeasureSpec.UNSPECIFIED || mode == MeasureSpec.AT_MOST) {
            if(height == 0) {
                // measure vertical decor (i.e. PagerTitleStrip) based on ViewPager implementation
                decorHeight = 0;
                for (int i = 0; i < getChildCount(); i++) {
                    View child = getChildAt(i);
                    LayoutParams lp = (LayoutParams) child.getLayoutParams();
                    if(lp != null && lp.isDecor) {
                        int vgrav = lp.gravity & Gravity.VERTICAL_GRAVITY_MASK;
                        boolean consumeVertical = vgrav == Gravity.TOP || vgrav == Gravity.BOTTOM;
                        if(consumeVertical) {
                            decorHeight += child.getMeasuredHeight() ;
                        }
                    }
                }

                // make sure that we have an height (not sure if this is necessary because it seems that onPageScrolled is called right after
                int position = getCurrentItem();
                View child = getViewAtPosition(position);
                if (child != null) {
                    height = measureViewHeight(child);
                }
                //Log.d(TAG, "onMeasure height:" + height + " decor:" + decorHeight);

            }
            int totalHeight = height + decorHeight + getPaddingBottom() + getPaddingTop();
            heightMeasureSpec = MeasureSpec.makeMeasureSpec(totalHeight, MeasureSpec.EXACTLY);
            //Log.d(TAG, "onMeasure total height:" + totalHeight);
        }

        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }

    @Override
    public void onPageScrolled(int position, float offset, int positionOffsetPixels) {
        super.onPageScrolled(position, offset, positionOffsetPixels);
        // cache scrolled view heights
        if (scrollingPosition != position) {
            scrollingPosition = position;
            // scrolled position is always the left scrolled page
            View leftView = getViewAtPosition(position);
            View rightView = getViewAtPosition(position + 1);
            if (leftView != null && rightView != null) {
                leftHeight = measureViewHeight(leftView);
                rightHeight = measureViewHeight(rightView);
                animateHeight = true;
                //Log.d(TAG, "onPageScrolled heights left:" + leftHeight + " right:" + rightHeight);
            } else {
                animateHeight = false;
            }
        }
        if (animateHeight) {
            int newHeight = (int) (leftHeight * (1 - offset) + rightHeight * (offset));
            if (height != newHeight) {
                //Log.d(TAG, "onPageScrolled height change:" + newHeight);
                height = newHeight;
                requestLayout();
                invalidate();
            }
        }
    }

    private int measureViewHeight(View view) {
        view.measure(getChildMeasureSpec(widthMeasuredSpec, getPaddingLeft() + getPaddingRight(), view.getLayoutParams().width), MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
        return view.getMeasuredHeight();
    }

    protected View getViewAtPosition(int position) {
        if(getAdapter() != null) {
            Object objectAtPosition = ((PagerAdapterWrapper) getAdapter()).getObjectAtPosition(position);
            if (objectAtPosition != null) {
                for (int i = 0; i < getChildCount(); i++) {
                    View child = getChildAt(i);
                    if (child != null && getAdapter().isViewFromObject(child, objectAtPosition)) {
                        return child;
                    }
                }
            }
        }
        return null;
    }


    /**
     * Wrapper for PagerAdapter so we can ask for Object at index
     */
    private class PagerAdapterWrapper extends PagerAdapter {
        private final PagerAdapter innerAdapter;
        private SparseArray<Object> objects;

        public PagerAdapterWrapper(PagerAdapter adapter) {
            this.innerAdapter = adapter;
            this.objects = new SparseArray<>(adapter.getCount());
        }


        @Override
        public void startUpdate(ViewGroup container) {
            innerAdapter.startUpdate(container);
        }

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            Object object = innerAdapter.instantiateItem(container, position);
            objects.put(position, object);
            return object;
        }

        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            innerAdapter.destroyItem(container, position, object);
            objects.remove(position);
        }

        @Override
        public void setPrimaryItem(ViewGroup container, int position, Object object) {
            innerAdapter.setPrimaryItem(container, position, object);
        }

        @Override
        public void finishUpdate(ViewGroup container) {
            innerAdapter.finishUpdate(container);
        }

        @Override
        public Parcelable saveState() {
            return innerAdapter.saveState();
        }

        @Override
        public void restoreState(Parcelable state, ClassLoader loader) {
            innerAdapter.restoreState(state, loader);
        }

        @Override
        public int getItemPosition(Object object) {
            return innerAdapter.getItemPosition(object);
        }

        @Override
        public void notifyDataSetChanged() {
            innerAdapter.notifyDataSetChanged();
        }

        @Override
        public void registerDataSetObserver(DataSetObserver observer) {
            innerAdapter.registerDataSetObserver(observer);
        }

        @Override
        public void unregisterDataSetObserver(DataSetObserver observer) {
            innerAdapter.unregisterDataSetObserver(observer);
        }

        @Override
        public float getPageWidth(int position) {
            return innerAdapter.getPageWidth(position);
        }

        @Override
        public CharSequence getPageTitle(int position) {
            return innerAdapter.getPageTitle(position);
        }

        @Override
        public int getCount() {
            return innerAdapter.getCount();
        }

        @Override
        public boolean isViewFromObject(View view, Object object) {
            return innerAdapter.isViewFromObject(view, object);
        }

        public Object getObjectAtPosition(int position) {
            return objects.get(position);
        }
    }
}

first_fragment.xml

<android.support.v7.widget.RecyclerView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/lvCheckIn"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:requiresFadingEdge="none"
    android:fadingEdgeLength="0dp"
    android:orientation="vertical" />

Weitere Daten beim Scrollen zum RecyclerView hinzufügen -

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

        }

        @Override
        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
            super.onScrolled(recyclerView, dx, dy);
            visibleItemCount = recyclerView.getChildCount();
            totalItemCount = adapter.getItemCount();
            firstVisibleItem = ((LinearLayoutManager) recyclerView.getLayoutManager()).findFirstVisibleItemPosition();
            if (loading) {
                if (totalItemCount > previousTotal) {
                    loading = false;
                    previousTotal = totalItemCount;
                }
            }
            if (!loading && (totalItemCount - visibleItemCount)
                    <= (firstVisibleItem + visibleThreshold) && current_page < totalPages) {
                // End has been reached

                // Do something
                current_page++;
                // Sending request to server

                loading = true;
            }
        }
    };

Wenn Daten über die API empfangen werden (Adapter oben bereits hinzugefügt) -

adapter.addNewList(homePageNew.checkin_stores.stores);

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