I have an activity which opens a fragment with view pager. when I change between the tabs I get this error: The specified child already has a parent. You must call removeView() on the child's parent first.
I think is the problem is from the header of the RecyclerView and I posted a new question about it here
the view pager code is:
private void mViewPager(ViewPager viewPager) { ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager()); adapter.addFragment(new a_Frag(), getString("A")); adapter.addFragment(new b_Frag(), getString("B")); adapter.addFragment(new c_Frag(), getString("C")); viewPager.setAdapter(adapter); } the a_frag code as example:
public class a_Frag extends Fragment { RecyclerView recyclerView; public a_Frag() { } @Override public void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); } @Override public void onActivityCreated(@Nullable Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View view = inflater.inflate(R.layout.rv, container, false); recyclerView = (RecyclerView) view.findViewById(R.id.rv); recyclerView.setLayoutManager(new LinearLayoutManager(getContext())); recyclerView.setAdapter(new a_Adapter(getContext(), R.layout.group_header)); return recyclerView; } ExpandableRecyclerView code:
public class ExpandableRecyclerView extends RecyclerView { public ExpandableRecyclerView(Context context) { super(context, null); initRecycler(); } public ExpandableRecyclerView(Context context, AttributeSet attrs) { super(context, attrs); initRecycler(); } public ExpandableRecyclerView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); initRecycler(); } private void initRecycler() { setClipToPadding(false); setItemAnimator(new DefaultItemAnimator()); } @Override public Parcelable onSaveInstanceState() { //begin boilerplate code that allows parent classes to save state Parcelable superState = super.onSaveInstanceState(); SavedState ss = new SavedState(superState); //end if (getAdapter() != null) ss.stateToSave = ((Adapter) this.getAdapter()).getExpandedGroups(); return ss; } @Override public void onRestoreInstanceState(Parcelable state) { //begin boilerplate code so parent classes can restore state if (!(state instanceof SavedState)) // if state is not instance of out SaveState just restore in reg way { super.onRestoreInstanceState(state); return; } // else if cast him to SavedState SavedState ss = (SavedState) state; super.onRestoreInstanceState(ss.getSuperState()); //end if (getAdapter() != null) ((Adapter) getAdapter()).setExpandedGroups(ss.stateToSave); } @Override public void setAdapter(RecyclerView.Adapter adapter) { if (!(adapter instanceof Adapter)) throw new IllegalArgumentException("adapter has to be of type ExpandableRecyclerView.Adapter"); super.setAdapter(adapter); } public interface OnChildItemClickedListener { void onChildItemClicked(int group, int position); } static class SavedState implements Parcelable { public static final SavedState EMPTY_STATE = new SavedState() { }; //required field that makes Parcelables from a Parcel public static final Creator<SavedState> CREATOR = new Creator<SavedState>() { public SavedState createFromParcel(Parcel in) { return new SavedState(in); } public SavedState[] newArray(int size) { return new SavedState[size]; } }; SparseBooleanArray stateToSave; Parcelable superState; SavedState() { superState = null; } SavedState(Parcelable superState) { this.superState = superState != EMPTY_STATE ? superState : null; } private SavedState(Parcel in) { Parcelable superState = in.readParcelable(ExpandableRecyclerView.class.getClassLoader()); this.superState = superState != null ? superState : EMPTY_STATE; this.stateToSave = in.readSparseBooleanArray(); } @Override public int describeContents() { return 0; } @Override public void writeToParcel(@NonNull Parcel out, int flags) { out.writeParcelable(superState, flags); out.writeSparseBooleanArray(this.stateToSave); } public Parcelable getSuperState() { return superState; } } public static abstract class Adapter<CVH extends ViewHolder, GVH extends ViewHolder, C, G> extends RecyclerView.Adapter<ViewHolder> { private static final int TYPE_HEADER = 0; SparseBooleanArray expanded = new SparseBooleanArray(); private OnChildItemClickedListener onChildItemClickedListener; public Adapter() { } boolean isExpanded(int group) { return expanded.get(group); } SparseBooleanArray getExpandedGroups() { return expanded; } public void setExpandedGroups(SparseBooleanArray expanded) { this.expanded = expanded; } public void expand(int group) { if (isExpanded(group)) return; // this lines of code calculate number of shown item in recycler view. also group is counting . int position = 0; for (int i = 0; i < group; i++) { position++; if (isExpanded(i)) position += getChildItemCount(i); } position++; // this for percent group notifyItemRangeInserted(position, getChildItemCount(group)); // notify recycler view for expanding expanded.put(group, true); // save expanding in sparce array } public void collapse(int group) { if (!isExpanded(group)) // if is not expanded . so nothing to collapse. return; int position = 0; for (int i = 0; i < group; i++) { position++; if (isExpanded(i)) position += getChildItemCount(i); // item } position++; notifyItemRangeRemoved(position, getChildItemCount(group)); expanded.put(group, false); } public abstract int getGroupItemCount(); public abstract int getChildItemCount(int group); @Override public int getItemCount() { int count = 0; for (int i = 0; i <= getGroupItemCount(); i++) { count += isExpanded(i) ? getChildItemCount(i) + 1 : 1; } return count; } public abstract G getGroupItem(int position); public abstract C getChildItem(int group, int position); public Object getItem(int i) { int group = 0; while (group <= getGroupItemCount()) { if (i > 0 && !isExpanded(group)) { i--; group++; continue; } if (i > 0 && isExpanded(group)) { i--; if (i < getChildItemCount(group)) return getChildItem(group, i); i -= getChildItemCount(group); group++; continue; } if (i == 0) return getGroupItem(group); } throw new IndexOutOfBoundsException(); } @Override public void onBindViewHolder(ViewHolder holder, int i) { int group = 0; while (group <= getGroupItemCount()) { if (i > 0 && !isExpanded(group)) { i--; group++; continue; } if (i > 0 && isExpanded(group)) { i--; if (i < getChildItemCount(group)) { onBindChildViewHolder((CVH) holder, group, i); return; } i -= getChildItemCount(group); group++; continue; } if (i == 0) { onBindGroupViewHolder((GVH) holder, group); return; } } throw new IndexOutOfBoundsException(); } @Override public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { return viewType == TYPE_HEADER ? onCreateGroupViewHolder(parent) : onCreateChildViewHolder(parent, viewType); } protected abstract GVH onCreateGroupViewHolder(ViewGroup parent); protected abstract CVH onCreateChildViewHolder(ViewGroup parent, int viewType); public abstract int getChildItemViewType(int group, int position); @Override public int getItemViewType(int i) { int group = 0; while (group <= getGroupItemCount()) { if (i > 0 && !isExpanded(group)) { i--; group++; continue; } if (i > 0 && isExpanded(group)) { i--; if (i < getChildItemCount(group)) return getChildItemViewType(group, i); i -= getChildItemCount(group); group++; continue; } if (i == 0) return TYPE_HEADER; } throw new IndexOutOfBoundsException(); } public void setOnChildItemClickedListener(OnChildItemClickedListener onItemClickedListener) { this.onChildItemClickedListener = onItemClickedListener; } public void onBindChildViewHolder(CVH holder, final int group, final int position) { holder.itemView.setOnClickListener(new OnClickListener() { public void onClick(View v) { if (Adapter.this.onChildItemClickedListener != null) { Adapter.this.onChildItemClickedListener.onChildItemClicked(group, position); } } }); } public void onBindGroupViewHolder(final GVH holder, final int group) { if (holder instanceof GroupViewHolder) ((GroupViewHolder) holder).setExpanded(isExpanded(group)); holder.itemView.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { if (isExpanded(group)) { collapse(group); if (holder instanceof GroupViewHolder) ((GroupViewHolder) holder).collapse(); } else { expand(group); if (holder instanceof GroupViewHolder) ((GroupViewHolder) holder).expand(); } } }); } } public static abstract class GroupViewHolder extends ViewHolder { public GroupViewHolder(View itemView) { super(itemView); } public abstract void expand(); public abstract void collapse(); public abstract boolean isExpanded(); public abstract void setExpanded(boolean expanded); } public static class SimpleGroupViewHolder extends GroupViewHolder { ImageView expandedIndicator; TextView text; private boolean expanded; public SimpleGroupViewHolder(Context context) { super(View.inflate(context, R.layout.group_header, null)); itemView.setLayoutParams(new LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT)); expandedIndicator = (ImageView) itemView.findViewById(R.id.carbon_groupExpandedIndicator); text = (TextView) itemView.findViewById(R.id.carbon_groupText); } public SimpleGroupViewHolder(Context context, int layout) { super(View.inflate(context, layout, null)); itemView.setLayoutParams(new LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT)); expandedIndicator = (ImageView) itemView.findViewById(R.id.carbon_groupExpandedIndicator); text = (TextView) itemView.findViewById(R.id.carbon_groupText); } public void expand() { ValueAnimator animator = ValueAnimator.ofFloat(0, 1); animator.setInterpolator(new DecelerateInterpolator()); animator.setDuration(200); animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator animation) { ViewHelper.setRotation(expandedIndicator, 180 * (float) (animation.getAnimatedValue())); expandedIndicator.postInvalidate(); } }); animator.start(); expanded = true; } public void collapse() { ValueAnimator animator = ValueAnimator.ofFloat(1, 0); animator.setInterpolator(new DecelerateInterpolator()); animator.setDuration(200); animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator animation) { ViewHelper.setRotation(expandedIndicator, 180 * (float) (animation.getAnimatedValue())); expandedIndicator.postInvalidate(); } }); animator.start(); expanded = false; } @Override public boolean isExpanded() { return expanded; } public void setExpanded(boolean expanded) { ViewHelper.setRotation(expandedIndicator, expanded ? 180 : 0); this.expanded = expanded; } public String getText() { return text.getText().toString(); } public void setText(String t) { text.setText(t); } } } the adapters are the same except for the data so I will put one example:
Adapter code example:
public class Adapter extends ExpandableRecyclerView.Adapter<Adapter.ChildViewHolder, Adapter.GroupViewHolder, String, String> { private DatabaseHelper db; private ArrayList List; private int layout; public Adapter(Context c, int resource) { layout = resource; db = new DatabaseHelper(c); List = db.getRecords();//returns list } @Override public int getGroupItemCount() { return List.size() - 1; } @Override public int getChildItemCount(int i) { return 1; } @Override public String getGroupItem(int i) { return null; } @Override public String getChildItem(int group, int child) { return null; } @Override protected GroupViewHolder onCreateGroupViewHolder(ViewGroup parent) { return new GroupViewHolder(parent.getContext(), layout); } @Override protected ChildViewHolder onCreateChildViewHolder(ViewGroup parent, int viewType) { View rootView = LayoutInflater.from(parent.getContext()).inflate(R.layout.group_item, parent, false); return new ChildViewHolder(rootView); } @Override public void onBindGroupViewHolder(GroupViewHolder holder, int group) { super.onBindGroupViewHolder(holder, group); holder.setText1("A"); holder.setText2("B"); } @Override public void onBindChildViewHolder(ChildViewHolder holder, int group, int position) { super.onBindChildViewHolder(holder, group, position); holder.t1.setText("t1"); holder.t2.setText("t2"); holder.t3.setText("t3"); holder.t4.setText("t4"); } @Override public int getChildItemViewType(int i, int i1) { return 1; } static class GroupViewHolder extends ExpandableRecyclerView.GroupViewHolder { ImageView expandedIndicator; TextView text1; TextView text2; private boolean expanded; GroupViewHolder(Context context, int layout) { super(View.inflate(context, layout, null)); itemView.setLayoutParams(new RecyclerView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT)); expandedIndicator = (ImageView) itemView.findViewById(R.id.groupExpandedIndicator); text1 = (TextView) itemView.findViewById(R.id.text1); text2 = (TextView) itemView.findViewById(R.id.text2); } public void expand() { ValueAnimator animator = ValueAnimator.ofFloat(0, 1); animator.setInterpolator(new DecelerateInterpolator()); animator.setDuration(200); animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator animation) { ViewHelper.setRotation(expandedIndicator, 180 * (float) (animation.getAnimatedValue())); expandedIndicator.postInvalidate(); } }); animator.start(); expanded = true; } public void collapse() { ValueAnimator animator = ValueAnimator.ofFloat(1, 0); animator.setInterpolator(new DecelerateInterpolator()); animator.setDuration(200); animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator animation) { ViewHelper.setRotation(expandedIndicator, 180 * (float) (animation.getAnimatedValue())); expandedIndicator.postInvalidate(); } }); animator.start(); expanded = false; } @Override public boolean isExpanded() { return expanded; } public void setExpanded(boolean expanded) { ViewHelper.setRotation(expandedIndicator, expanded ? 180 : 0); this.expanded = expanded; } void setText1(String t) { text1.setText(t); } void setText2(String t) { text2.setText(t); } } class ChildViewHolder extends RecyclerView.ViewHolder { private TextView t1; private TextView t2; private TextView t3; private TextView t4; ChildViewHolder(View itemView) { super(itemView); t1 = (TextView) itemView.findViewById(R.id.tv1); t2 = (TextView) itemView.findViewById(R.id.tv2); t3 = (TextView) itemView.findViewById(R.id.tv3); t4 = (TextView) itemView.findViewById(R.id.tv4); } } } group_header.xml:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:clickable="true"> <android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android" xmlns:card_view="http://schemas.android.com/apk/res-auto" android:id="@+id/Card1" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_gravity="center" android:layout_marginLeft="7dp" android:layout_marginRight="7dp" android:layout_marginTop="10dp" card_view:cardCornerRadius="10dp" card_view:cardElevation="5dp"> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="right" android:orientation="horizontal"> <TextView android:id="@+id/text1" style="@style/MyLargeTextAppearance" android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:gravity="center" android:padding="16dp" android:textColor="@color/highlight" android:textStyle="bold" /> </LinearLayout> </android.support.v7.widget.CardView> <android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android" xmlns:card_view="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_below="@id/Card1" android:layout_gravity="center" android:layout_marginLeft="7dp" android:layout_marginRight="7dp" android:layout_marginTop="1dp" card_view:cardCornerRadius="10dp" card_view:cardElevation="5dp"> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="right" android:orientation="horizontal"> <TextView android:id="@+id/text2" style="@style/MyLargeTextAppearance" android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:gravity="center" android:padding="16dp" android:textColor="@color/highlight" android:textStyle="bold" /> <ImageView android:id="@+id/groupExpandedIndicator" android:layout_width="24dp" android:layout_height="24dp" android:layout_gravity="center_vertical" android:layout_marginEnd="16dp" android:layout_marginRight="16dp" app:srcCompat="@drawable/ic_expand_more" /> </LinearLayout> </android.support.v7.widget.CardView> </RelativeLayout> group_item.xml:
<?xml version="1.0" encoding="utf-8"?> <android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android" xmlns:card_view="http://schemas.android.com/apk/res-auto" android:id="@+id/card" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_gravity="center" android:layout_marginLeft="7dp" android:layout_marginRight="7dp" android:layout_marginTop="10dp" card_view:cardCornerRadius="10dp" card_view:cardElevation="5dp"> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="wrap_content" android:background="@color/materialGray" android:orientation="vertical" android:padding="@dimen/activity_horizontal_margin"> <TextView android:id="@+id/t1" style="@style/MyLargeTextAppearance" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center" android:text="TextView" /> <View android:layout_width="match_parent" android:layout_height="1dp" android:background="@color/separatorViewBackground" /> <TextView android:id="@+id/t2" style="@style/MyLargeTextAppearance" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center" android:text="TextView" /> <View android:layout_width="match_parent" android:layout_height="1dp" android:background="@color/separatorViewBackground" /> <TextView android:id="@+id/t3" style="@style/MyLargeTextAppearance" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center" android:text="TextView"/> <View android:layout_width="match_parent" android:layout_height="1dp" android:background="@color/separatorViewBackground" /> <TextView android:id="@+id/t4" style="@style/MyLargeTextAppearance" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center" android:text="TextView" /> </LinearLayout> </android.support.v7.widget.CardView> 1 Answers
Answers 1
Try changing to:
@Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){ View view = inflater.inflate(R.layout.rv, container, false); recyclerView = (RecyclerView) view.findViewById(R.id.rv); recyclerView.setLayoutManager(new LinearLayoutManager(getContext())); recyclerView.setAdapter(new a_Adapter(getContext(), R.layout.group_header)); if (recyclerView != null) { return recyclerView; } return null; } 
0 comments:
Post a Comment