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View not hiding when dynamically done in recycler view item

I am using RecyclerView to list Items and In each single list displaying an image which will be Visible/Gone dynamically. I am using View.GONE to hide the view.
In a condition where the image should hide is not working always. It is still showing in screen,and also in debug mode i have checked that and when getting the
image.getVisiblity() it is giving me int value "8" which means the view is Gone,But still i can see that image in that list.
It happens only sometimes.
And i tried to use View.INVISIBLE and it is working all the time but it is taking the space in layout which is as expected
I am using sparseArray to store all the holders classes.I have written a method in Adapter and calling this from activity.I am trying to hide the replayIcon view
public void handleReplayButton(int pos,Boolean isDisplay) {
Holder holder = holderSparseArray.get(pos);
if(holder != null) {
if (isDisplay != null && isDisplay == true) {
holder.playIcon.setVisibility(View.GONE);
holder.pauseIcon.setVisibility(View.GONE);
holder.replayIcon.setVisibility(View.VISIBLE);
} else if(isDisplay != null && isDisplay == false) {
holder.playIcon.setVisibility(View.VISIBLE);
holder.pauseIcon.setVisibility(View.GONE);
holder.replayIcon.setVisibility(View.GONE);
} else {
holder.playIcon.setVisibility(View.GONE);
holder.pauseIcon.setVisibility(View.VISIBLE);
holder.replayIcon.setVisibility(View.GONE);
}
}
}
Here it is going to the last else statement what i want and it is setting the view to GONE.and when i call holder.replayIcon.getVisibility() it is giving me int 8 but,still i can see the icon

Try calling invisible at the end of one statement which makes it visible and vice versa.
Or
You can also try to put notifydatasetchanged().

You will have to call notifyDataSetChanged() to refresh the list in the recycler view.
But since you have to remove an item, you can also use notifyItemRemoved
Also, if you are using setVisibility() method to HIDE the view, then make sure you also set the view as VISIBLE for valid items, because the items are reused in a recycler view.
For more : https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Adapter

If you will call notifyDataSetChanged() - it will update all the items in the list.
Don't do that if you need to update special items by index because it will take a lot of memory to redraw the all views.
Instead like the guys wrote before you should use notifyItemChanged(), notifyItemInserted() or notifyItemRemoved().
If you want to update couple views use can use notifyItemRangeChanged(), notifyItemRangeRemoved() or notifyItemRangeInserted().
You can read more about it here
Also there is one way to it. You can use DiffUtils callbacks.
Pretty good approach that work with animation already.
DiffUtils Calbacks

ViewPager2 default position

I'm creating a slideshow with ViewPager2. For example, the slideshow has 3 items and I want to show the second item when the activity opens. I use setCurrentItem(int item, boolean smoothScroll) method but it doesn't work and nothing happens. How can I achieve it?
viewPager.adapter = adapter
viewPager.setCurrentItem(1, true)

I think an easier more reliable fix is to defer to next run cycle instead of unsecure delay e.g
viewPager.post {
viewPager.setCurrentItem(1, true)
}

setCurrentItem(int item, boolean smoothScroll) works correctly in ViewPager but in ViewPager2 it does not work as expected. Finally, I faced this problem by adding setCurrentItem(int item, boolean smoothScroll) method into a delay like this:
Handler().postDelayed({
view.viewPager.setCurrentItem(startPosition, false)
}, 100)

Do not use timers, you will run into a lot of probable states in which the user has a slow phone and it actually takes a lot longer than 100 ms to run, also, you wouldn't want too slow of a timer making it ridiculously un-reliable.
Below we do the following, we set a listener to our ViewTreeObserver and wait until a set number of children have been laid out in our ViewPager2's RecyclerView (it's inner working). Once we are sure x number of items have been laid out, we start our no-animation scroll to start at the position.
val recyclerView = (Your ViewPager2).getChildAt(0)
recyclerView.apply {
val itemCount = adapter?.itemCount ?: 0
if(itemCount >= #(Position you want to scroll to)) {
viewTreeObserver.addOnGlobalLayoutListener(object: ViewTreeObserver.OnGlobalLayoutListener {
override fun onGlobalLayout() {
viewTreeObserver.removeOnGlobalLayoutListener(this)
// False for without animation scroll
(Your ViewPager2).scrollToPosition(#PositionToStartAt, false)
}
}
}

First off, I think that the accepted answer shouldn't be #hosseinAmini 's, since it's suggesting to use a delay to work around the problem. You should first be looking for what the assumed bug is caused by, rather than trusting unreasonable solutions like that.
#Rune's proposal is correct, instead; so I'm quoting their code in my answer:
viewPager.post {
viewPager.setCurrentItem(1, true)
}
The only thing I'd argue about is the aforementioned one's belief that their solution is just deferring the execution of that lambda in the next run cycle. This wouldn't make anything buggy work properly. Rather, what it is actually being done is deferring the execution of that lambda to once the view has been attached to a window, which implies it's also been added to a parent view. Indeed, there looks to be an issue as to changing the current ViewPager2 item before being attached to a window. Some evidence to support this claim follows:
Using whichever Handler won't work nearly as effectively.
Handler(Looper.getMainLooper()).post {
viewPager.setCurrentItem(1, true) // Not working properly
}
From a theoretical standpoint, it might incidentally work due to the ViewPager2 being attached to a window acquiring priority in the message queue of the main looper, but this shouldn't ever be relied upon as there's just no guarantee that it'll work (it's even more likely it won't) and if it even turned out to be working, further investigation running multiple tests should make my point clear.
View.handler gets null, which means the view hasn't been attached to any window yet.
View.handler // = null
Despite Android UI being tied to the main looper, which will always uniquely correspond to the main thread –hence also called the UI thread,– a weird design choice stands in the handler not being associated to each view until they get attached to a window. A reason why this may lay on the consequent inability of views to schedule any work on the main thread while they're not part of the hierarchy, which may turn useful when implementing a view controller that schedules view updates while unaware of their lifecycle (in which case it would employ the View's handler, if any — or just skip scheduling whatever it was going to if none).
EDIT:
Also, #josias has pointed out in a comment that it'd be clearer to use:
viewPager.doOnAttach {
viewPager.setCurrentItem(1, true)
}
Thanks for that suggestion! It expresses better the actual intent, rather than relying on the behavior of the View.post method.

Do not use timers and all that stuff with 'post', it's not the reliable solution and just a piece of code that smells.
Instead, try use viewPager.setCurrentItem(1, false). That 'false' is about smoothScroll, you can't smooth scroll your viewPager2 when your activity is just opened. Tested it on a fragment in onViewCreated() method, it also didn't work with "true", but works with "false"

As it was mentioned above you have to use setCurrentItem(position, smoothScroll) method on ViewPager2 in order to show selected item. To make it work you have to define a callback, here is an example:
ViewPager2.OnPageChangeCallback callback = new ViewPager2.OnPageChangeCallback() {
#Override
public void onPageSelected(int position) {
super.onPageSelected(position);
}
};
And then you have to register it as follow:
viewPager.registerOnPageChangeCallback(callback);
Also do not forget to unregister it:
viewPager.unregisterOnPageChangeCallback(callback);
When you call setCurrentItem(position) method it will call onPageSelected(int position) method from your callback passing your argument, and then method createFragment(int position) from FragmentStateAdapter class will be called to show your fragment.

I tried changing viewpager2 page in Handler().dely() and viewPager2.post{} and even 'viewPager2.get(0).post all didn't work for me, I'm using ViewPager with FragmentStateAdapter with Tablayout.
What worked for me is changing the position of the RecylerView in ViewPager2 after binding FragmentStateAdapter to yourViewPager2View.adapter manually:
(yourViewPager2View[0] as RecyclerView).scrollToPosition(moveToTabNumber)
Why
My problem is onCreateFragment(position:Int):Fragmeet function in FragmentStateAdapter always starting fragment at 0 position no matter what pageNumber I set the page
viewPager.setCurrentItem = pageNumber
I checked where it's called in FragmentStateAdapter it's called in FragmentStateAdapter:
onBindViewHolder(final #NonNull FragmentViewHolder holder, int position)`
so all I needed is to force onBindViewHolder to call onCreateFragment(position:Int) with the page number I wanted.

mViewPager.setCurrentItem(1, true); ---> this is sufficient as you written above
That should work,
in doubt, just check your position:
#Override
public void onPageSelected(int i) {
if (LOG_DEBUG) Log.v(TAG, " ++++++++ onPageSelected: " + i);
mViewPager.setCurrentItem(i);
//TODO You can use this position: to write other dependent logic
}
and also check
getItem(int position) in PagerAdapter
or else paste your code.

I noticed that it works fine when the view is initially created if you opt to not animate it.
viewPager2.setCurrentItem(index, false)
This is usually fine depending on your use case - this initial/default item probably doesn't need to be animated in.

I met the same problem. In my case, I make the viewPager2 Gone by default until network requests succeed, I fix it by setting the CurrentItem after I make the viewPager2 visible.

My answer may not be helpful now but i see no harm to post my expreince, i just came to this problem using ViewPager and ViewPager2 and unexpectedly solved it by just changing some line codes order.
Here is (java) solution for ViewPager:
reviewWordViewPager.addOnPageChangeListener(changeListener);
reviewWordViewPager.setCurrentItem(viewPosition, true/false);
reviewWordTabIndicator.setupWithViewPager(reviewWordViewPager, true);
(Java) solution for ViewPager2:
wordViewPager.registerOnPageChangeCallback(viewPager2OnPageChangeCallback);
wordViewPager.setCurrentItem(vpPosition, true/false);
new TabLayoutMediator(tabIndicator, wordViewPager,
((tab, position) -> tab.setText(viewPagerTitle[position]))).attach();
I did not look up for ViewPager2 whether it needs the following old code used in ViewPager
#Override
public int getItemPosition(#NonNull Object object) {
// refresh all fragments when data set changed
return POSITION_NONE;
}
But surprisingly no need for it in ViewPager2 to solve the problem i've been having, hope it helps others
In case you use context.startActivity to start new activities no need to use wordViewPager.setCurrentItem(item, smoothScroll) in your onResume function to get back to the last selected tab before you started new activity you just save ViewPager/ViewPager2 position like vpPisition = wordViewPager.getCurrentItem(); in onStop function.
vpPisition is a global variable.

as #Daniel Kim but a java version
RecyclerView rvOfViewPager2 = (RecyclerView) viewPager2.getChildAt(0);
rvOfViewPager2.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener()
{
#Override
public void onGlobalLayout()
{
rvOfViewPager2.getViewTreeObserver().removeOnGlobalLayoutListener(this);
viewPager2.setCurrentItem(currentTabId, false);
}
});

First You need to Initilaze the Main activity under any listener or button You want then After that You need to put this Line..
here MainActvity is the Viewpager Main Class You are using and and 2 is the position where you want to move
MainActivity main = (MainActivity ) mContext;
main.selectTab(2, true);

How to save the state of views held in dynamic viewpager

I have an enhanced loop, which will dynamically inflate however many layouts relevant to the number of values held in my array.
This works perfectly however, there is a method being called on each iteration, which also works but there is a big bug that I need help resolving.
Imagine there are 5 items in my array, therefore 5 layouts are inflated, in these layouts there is a little scratchcard type section on the layout.
Now if the user is on page 1, uses the scratchcard, then moves on to page 2, uses the scratchcard etc etc, it works fine.
But if the user is on page 1 and then goes to say, page 5 and then back to page 1 (basically in a random order), the scratchcard doesn't work.
From my understanding, the reason for this is that the method is being called an implemented on each iteration and the view is losing its state if the user scrolls back or scrolls in random orders.
Therefore I need a way to save the created view state in my viewpager.
Is this possible for my scenario? I have tried my best to find a solution, but cannot find something that feels relevant to my question.
Here is a snippet of the code in question. Thanks for any guidance or suggestions!
for (String x : array1) {
//loop out the number of layouts relative to the number of questions held in x
View current_layout = LayoutInflater.from(getActivity()).inflate(R.layout.question_fragment, null);
//use the pageAdapter to add the layout to the users view
pagerAdapter.addView(current_layout);
//call method to add functionality to the scratchcard
isCorrect(current_layout);
}
public void isCorrect(View current_layout) {
ScratchoffController controller1 = new ScratchoffController(getActivity())
.setThresholdPercent(0.40d)
.setTouchRadiusDip(getActivity(), 30)
.setFadeOnClear(true)
.setClearOnThresholdReached(true)
.setCompletionCallback(() -> {
})
.attach(current_layout.findViewById(R.id.scratch_view1), current_layout.findViewById(R.id.scratch_view_behind1));
ScratchoffController controller2 = new ScratchoffController(getActivity())
.setThresholdPercent(0.40d)
.setTouchRadiusDip(getActivity(), 30)
.setFadeOnClear(true)
.setClearOnThresholdReached(true)
.setCompletionCallback(() -> {
})
.attach(current_layout.findViewById(R.id.scratch_view2), current_layout.findViewById(R.id.scratch_view_behind2));
ScratchoffController controller3 = new ScratchoffController(getActivity())
.setThresholdPercent(0.40d)
.setTouchRadiusDip(getActivity(), 30)
.setFadeOnClear(true)
.setClearOnThresholdReached(true)
.setCompletionCallback(() -> {
})
.attach(current_layout.findViewById(R.id.scratch_view3), current_layout.findViewById(R.id.scratch_view_behind3));
ScratchoffController controller4 = new ScratchoffController(getActivity())
.setThresholdPercent(0.40d)
.setTouchRadiusDip(getActivity(), 30)
.setFadeOnClear(true)
.setClearOnThresholdReached(true)
.setCompletionCallback(() -> {
})
.attach(current_layout.findViewById(R.id.scratch_view4), current_layout.findViewById(R.id.scratch_view_behind4));
}

I ussually use ViewPager with Fragments and what you mention has happend to me when I try to keep references to the Fragment instances (in my case) outside of the viewpager.
This happens because the viewpager may create new instances of the Fragment it contains when you re-vist the tab in the way you mention. When this happens, the instance reference you hold outside of the viewpager is not anymore what the viewpager is showing.
In your case , according to this question, you have to oveeride instatiateItem and destroyItem. I think you can use these methods to save state restore state, and also you could update any external reference when instantiateItem is called.

visual indication of over scroll in android

I am trying to add some visual indication, that there are no more pages in the desired fling direction in the ViewPager. However I am struggling to find a place, where to put relevant code.
I have tried extending ViewPager class with following code, but the Toast is not displaying (ev.getOrientation() returns always 0). I have also tried the same with history points, but ev.getHistorySize() returns also 0.
What am I missing?
Class example:
public class CustomViewPager extends ViewPager {
public CustomViewPager(Context context) {
super(context);
}
public CustomViewPager(Context context, AttributeSet attrs) {
super(context, attrs);
}
/**
* #see android.support.v4.view.ViewPager#onTouchEvent(android.view.MotionEvent)
*/
#Override
public boolean onTouchEvent(MotionEvent ev) {
boolean result = super.onTouchEvent(ev);
switch (ev.getAction() & MotionEventCompat.ACTION_MASK) {
case MotionEvent.ACTION_MOVE:
if (ev.getOrientation() > 0) {
Toast.makeText(getContext(), "left", 0).show();
}
}
return result;
}
}

If you look at the v4 support library you will see there's a class used by ViewPager called EdgeEffectCompat (this provides the glow effect when you reach the beginning or end of a view pager in ICS+) If you look at the implementation in the compat library you will see that it has an if-statement to see if the build version is 14+ (ICS) or not. If it is, then it ends up eventually (if you trace long enough) using the normal EdgeEffect class that was inroduced in ICS. Otherwise it uses BaseEdgeEffectImpl which basically has nothing in it.
If you want, you can make your own custom ViewPager that uses EdgeEffect of your own. You can look at the android source code to see how they implemented EdgeEffect here which you can pretty much copy (just make sure to copy the overscroll_edge and overscroll_glow drawables in the AOSP /res/drawable directories to your own project since they are internal to android) or go ahead and create your own version.
Good luck.
(By the way, that's how they create the cool looking edge tilt effect in the launcher menu on ICS... so you can pretty much be as creative as you want with this ;)

I was trying to get the exact same effect that was asked in this question. I struggle with it and then I read #wnafee answer (I couldn't do it with out it).
But then I struggle to implement what was sound pretty simple from the answer.
I had so much trouble with implementing it, that I might didn't understand the answer correctly, but there were too many issues of inaccessible APIs since I wasn't working in the same package of the Compatibility library.
After I tried some approaches (none of them succeeded, and they were pretty complicated) I went to a slightly different direction, and now it works like a charm. I used some reflection, for the ones who never used it, don't worry it is really the basic of reflection.
I'm not sure if it's the best solution out there, but it worked for me, so if you would like to use it you are welcome. Please read Wnafee example since it explains some of the stuff that I did.
In order to accomplish this task you should just follow my three parts solution. (Will take you between 3-10 minutes)
Part I:
As Wnafee said I just made my own EdgeEffect class by copy paste the source code from here,
(just make sure to copy the overscroll_edge and overscroll_glow
drawables in the AOSP /res/drawable directories to your own project
since they are internal to android)
I only did 2 really small changes:
I declare that the class extends EdgeEffectCompat (I called my class EdgeEffectForEarlyVersions). public class EdgeEffectForEarlyVersions extends EdgeEffectCompat. The reason for doing this change is that the mLeftEdge and mRightEdge are of the type EdgeEffectCompat.
At the first line of the constructor of "my" new class I added a call to the parent constructor super(context);. Since there is no default constructor to EdgeEffectCompat you have to Explicitly call the constructor.
Part II
Besides that I wrote the another function. The purpose of the function is that in case of an early version (before ICS) we would like to use the EdgeEffectForEarlyVersions that we just copied. In order to get that purpose I used reflection.
This is the function:
private static void changeEdgeEffectCompactOnEarlyVersions(ViewPager viewPager, Context context)
{
/* In case that the version is earlier than 14 there is only empty implementation for the edge effect, therefore we change it.
* for more information look on the following links:
* 1. http://stackoverflow.com/questions/10773565/visual-indication-of-over-scroll-in-android
* 2. http://grepcode.com/file/repo1.maven.org/maven2/com.google.android/support-v4/r7/android/support/v4/view/ViewPager.java#ViewPager.0mLeftEdge
* 3. http://grepcode.com/file/repo1.maven.org/maven2/com.google.android/support-v4/r7/android/support/v4/widget/EdgeEffectCompat.java#EdgeEffectCompat
*/
if (Build.VERSION.SDK_INT < 14)
{
try
{
Class<ViewPager> viewPagerClass = ViewPager.class;
//Get the left edge field, since it is private we used getDeclaredField and not getDeclared
Field leftEdge = viewPagerClass.getDeclaredField("mLeftEdge");
leftEdge.setAccessible(true);
//Get the right edge field, since it is private we used getDeclaredField and not getDeclared
Field rightEdge = viewPagerClass.getDeclaredField("mRightEdge");
rightEdge.setAccessible(true);
EdgeEffectForEarlyVersions leftEdgeEffect = new EdgeEffectForEarlyVersions(context);
EdgeEffectForEarlyVersions rightEdgeEffect = new EdgeEffectForEarlyVersions(context);
//Set the mLeftEdge memeber of viewPager not to be the default one, but to be "our" edgeEffect
leftEdge.set(viewPager, leftEdgeEffect);
//Set the mRightEdge memeber of viewPager not to be the default one, but to be "our" edgeEffect
rightEdge.set(viewPager, rightEdgeEffect);
}
catch (Exception ex)
{
Log.e("refelection", ex.getMessage());
}
}
}
Part III
Now all there is left to do, is to call that function after you have the ViewPager Instance and nothing more.
I Hope it will help someone.

wnafee explained the solution well but for the lazy among us, i made an actual working implementation quite some time ago.
https://github.com/inovex/ViewPager3D
And if you just want overscroll take a look here:
https://github.com/inovex/ViewPager3D/issues/1

You have a lot of options, you can show a Toast, display a Dialog, make a TextView or image to appear over your UI, etc. Or because you know the amount of View items in the ViewPager, you could add different View at positions 0 and/or n + 1 with the message and make it bounce to the last View that actually contains your data.
You could implement:
viewPager.setOnPageChangeListener(new OnPageChangeListener() {
public void onPageSelected(int position) {
//TODO If position is the 0 or n item, add a view at 0 or at n+1 to indicate there is no more pages with data.
}
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
// TODO Show a Toast, View or do anything you want when position = your first/last item;
}
public void onPageScrollStateChanged(int state) {
}
});

just to complement #goBeepit dev answer when you create your own edgeffect class and you extend from EdgeEffectCompat some methods requires to be boolean. you can change those methods to boolean type and make then return true in any case, this way everything works fine

You can overload the setUserVisibleHint(boolean) function in your fragments. Pseudo code:
void setUserVisibleHint(boolean isVisibleToUser) {
// If this fragment is becoming visible
if (isVisibleToUser == true) {
// Check if it is the last fragment in the viewpager
if (indexOfThis == getActivity().indexOfLast) {
// Display right limit reached
Toast(..., "No more Frags to right",...)
}
// Check if it is the first fragment in the viewpager
else if (indexOfThis == getActivity().indexOfFirst) {
// Display Left Limit reached
Toast(..., "No more Frags to left",...)
}
}
}
I have not used this function for this purpose, but have used it for other reasons and it does fire appropriately. Hope this helps...

I've implemented a bounce back effect based on Renard's ViewPager3D: https://stackoverflow.com/a/17425468/973379

Usually with ViewPager, one uses a PagerAdapter such as FragmentPagerAdapter or FragmentStatePagerAdapter to flood the ViewPager with contents(your content are going to be views).
Now, when you use a PagerAdapter, you have one method called getCount(), http://developer.android.com/reference/android/support/v4/view/PagerAdapter.html#getCount%28%29 ,which will give you the size of the content.
Since you now, know the size you can easily display a message with an if control statement.
Try this code : http://developer.android.com/reference/android/support/v4/view/ViewPager.html
Note: I dont think you need a custom ViewPager. You will also need to understand Fragments for ViewPager. Look at samples in ApiDemos. Its a great source.

ListView item backgrounds not changing

I have an unusual issue with my ListView. I currently have a "deselectAll()" method which iterates through the items in my ListView and sets them to unchecked (the items implement the Checkable interface). The "checked" variable gets changed correctly (the view reports as not being checked), but the visual indicator (in this case, a background change) does not show the view as unchecked (the background stays the color of a checked item).
I am iterating and deselecting through my listview like so (I also added my declerations):
private ListView vw_entryList;
private void deselectAll() {
for (int i = 0; i < sAdapter.getCount(); i++) {
((Entry)vw_entryList.getItemAtPosition(i)).setChecked(false);
}
}
The code for my implemented setChecked() is as follows:
public void setChecked(boolean checked) {
_checked = checked;
if (checked) {
setBackgroundResource(R.drawable.listview_checked);
}
else {
setBackgroundResource(R.drawable.listview_unchecked);
}
invalidate();
}
It should be noted that when the items are clicked, they are toggled between checked and unchecked in the OnItemClickListener, and this works ok, with the background change and everything. The code for toggling is very similar:
public void toggle() {
_checked = !_checked;
setBackgroundResource(_checked ?
R.drawable.listview_checked : R.drawable.listview_unchecked);
invalidate();
}
The only difference I can see is where the methods are called from. toggle() is called from within the OnItemClickListener.onClick() method, while my deselectAll() is called from within a button's standard OnClickListener, both in the same class. Does anyone have any ideas as to why the background doesn't change when I call my deselectAll() function?

Do you have custom, non-standard color for the background? If so you might take a look at http://www.curious-creature.org/2008/12/22/why-is-my-list-black-an-android-optimization/ - it boils down to setting android:cacheColorHint attribute of your list to the background color. Maybe that will help.
Edited after further discussion:
I think you need to call getAdapter().notifyDataSetChanged() on the List rather than invalidate(). List is really build in the way that it is relying on adapter to provide the data. What you are doing in fact you have an implicit adapter - Entry is really kept in the adapter and by setting checked, you are changing the data model really, but if you do not call notifyDataSetChanged() the list does not really know that the model has changed and will not recreate the views (invalidate() will only redraw the existing ones).

After trying everything (thanks for your help Jarek), I found a solution that works for my purposes. Instead of implicitly calling the setChecked() within the view that was clicked, I leave it up to the setItemChecked() method within the ListView class.
My updated code:
private void deselectAll() {
for (int i = 0; i < sAdapter.getCount(); i++) {
vw_entryList.setItemChecked(i, false);
}
}
My best guess is that the ListView knows that its items implement the Checkable class, and thus requires itself to be the handler of all item operations. Something along those lines. If anyone can explain in more detail why this solution works while the others did not, I'll reward them with the answer and an upvote.