Glide - What is "isImagePosition(position)" in their documentation? - android

I'm trying to use Glide within my RecyclerView, and I've got a question regarding the code they used in their documentation. Code is shown below:
public void onBindViewHolder(ViewHolder holder, int position) {
if (isImagePosition(position)) {
String url = urls.get(position);
Glide.with(fragment)
.load(url)
.into(holder.imageView);
} else {
Glide.with(fragment).clear(holder.imageView);
holder.imageView.setImageDrawable(specialDrawable);
}
}
what I don't get is "isImagePosition(position)". What is this? Is this a check to see if the same view is being loaded to the same position when the RecyclerView's data set is updated? If that was the case, how would I implement "isImagePosition(position)"?
My recycler view uses a List ImageUrl.

If you are using recyclerView you can invoke it in the method ::
override fun onViewRecycled (holder: RecyclerView.ViewHolder) {
Glide.with (view.context) .clear (imageview)
super.onViewRecycled (holder)     
}

Related

TextViews recycle their positions and title when scrolling, Glide Gallery

I am trying to use the Glide Image Library to load images in a gridview an using REccycler View. However, I wanted the to have a title TextView beneath each image.
I have set a custom layout for this and tried to load the TextView in the onBindViewHolder. This works but on scrolling, the positions are recycled, and the TextViews Titles are changed, making a mess of it.
#Override
public void onBindViewHolder(MyViewHolder holder, int position) {
Image image = images.get(position);
// // setup Glide request without the into() method
// DrawableRequestBuilder<String> thumbnailRequest = Glide
// .with(mContext)
// .load(image.getMedium());
// pass the request as a a parameter to the thumbnail request
Glide.with(mContext).load(image.getMedium())
.thumbnail(0.3f)
.crossFade()
.diskCacheStrategy(DiskCacheStrategy.ALL)
.into(holder.thumbnail);
titleText.setText(image.getName());
}
How do I fix this dear developers?
I think the problem is that the titleText is not stored in the ViewHolder.
Save it inside your holder object and use:
holder.titleText.setText(image.getName());
This will change the TextView accordingly as the holder changes. Else it will be a mess as the holders are recycled.
something like:
class MyViewHolder extends RecyclerView.ViewHolder{
TextView titleText;
ImageView thumbnail;
.
.
.
#Override
public void onBindViewHolder(MyViewHolder holder, int position) {
Image image = images.get(position);
Glide.with(mContext).load(image.getMedium())
.thumbnail(0.3f)
.crossFade()
.diskCacheStrategy(DiskCacheStrategy.ALL)
.into(holder.thumbnail);
holder.titleText.setText(image.getName());
}
}

RecyclerView adapter showing wrong images

I have a RecyclerView adapter that looks like this:
public class RecyclerAdapter extends RecyclerView.Adapter<RecyclerAdapter.ViewHolder> {
private static Context context;
private List<Message> mDataset;
public RecyclerAdapter(Context context, List<Message> myDataset) {
this.context = context;
this.mDataset = myDataset;
}
public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnCreateContextMenuListener, View.OnClickListener {
public TextView title;
public LinearLayout placeholder;
public ViewHolder(View view) {
super(view);
view.setOnCreateContextMenuListener(this);
title = (TextView) view.findViewById(R.id.title);
placeholder = (LinearLayout) view.findViewById(R.id.placeholder);
}
}
#Override
public RecyclerAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.message_layout, parent, false);
ViewHolder vh = new ViewHolder((LinearLayout) view);
return vh;
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
Message item = mDataset.get(position);
holder.title.setText(item.getTitle());
int numImages = item.getImages().size();
if (numImages > 0) {
View test = LayoutInflater.from(holder.placeholder.getContext()).inflate(R.layout.images, holder.placeholder, false);
ImageView image = (ImageView) test.findViewById(R.id.image);
Glide.with(context)
.load("http://www.website.com/test.png")
.fitCenter()
.into(image);
holder.placeholder.addView(test);
}
}
#Override
public int getItemCount() {
return mDataset.size();
}
}
However, some of the items in the RecyclerView are showing images when they shouldn't be. How can I stop this from happening?
I do the check if (numImages > 0) { in onBindViewHolder(), but that's still not stopping it from showing images for items that shouldn't have images.
You should set imageView.setImageDrawable (null)
In onBindViewHolder() before setting the image using glide.
Setting image drawable to null fix the issue.
Hope it helps!
The problem is in onBindViewHolder, here:
if (numImages > 0) {
View test = LayoutInflater.from(holder.placeholder.getContext()).inflate(R.layout.images, holder.placeholder, false);
ImageView image = (ImageView) test.findViewById(R.id.image);
Glide.with(context)
.load("http://www.website.com/test.png")
.fitCenter()
.into(image);
holder.placeholder.addView(test);
}
If numImages is equal to 0, you're simply allowing the previously started load into the view you're reusing to continue. When it finishes, it will still load the old image into your view. To prevent this, tell Glide to cancel the previous load by calling clear:
if (numImages > 0) {
View test = LayoutInflater.from(holder.placeholder.getContext()).inflate(R.layout.images, holder.placeholder, false);
ImageView image = (ImageView) test.findViewById(R.id.image);
Glide.with(context)
.load("http://www.website.com/test.png")
.fitCenter()
.into(image);
holder.placeholder.addView(test);
} else {
Glide.clear(image);
}
When you call into(), Glide handles canceling the old load for you. If you're not going to call into(), you must call clear() yourself.
Every call to onBindViewHolder must include either a load() call or a clear() call.
I also had issues with RecyclerView showing wrong images. This happens because RecyclerView is not inflating view for every new list item: instead list items are being recycled.
By recycling views we can ruffly understand cloning views. A cloned view might have an image set from the previous interaction.
This is especially fair if your are using Picasso, Glide, or some other lib for async loading. These libs hold reference to an ImageView, and set an image on that refference when image is loaded.
By the time the image gets loaded, the item view might have gotten cloned, and the image is going to be set to the wrong clone.
To make a long story short, I solved this problem by restricting RecyclerView from cloning my item views:
setIsRecyclable(false)in ViewHolder constructor.
Now RecyclerView is working a bit slower, but at least the images are set right.
Or else cansel loading image in onViewRecycled(ViewHolder holde)
The issue here is that, as you are working with views that are going to be recycled, you'll need to handle all the possible scenarios at the time your binding your view.
For example, if you're adding the ImageView to the LinearLayout on position 0 of the data source, then, if position 4 doesn't met the condition, its view will most likely have the ImageView added when binding position 0.
You can add the content of R.layout.images content inside your
R.layout.message_layout layout's R.id.placeholder and showing/hiding the placeholder depending on the case.
So, your onBindViewHolder method would be something like:
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
Message item = mDataset.get(position);
holder.title.setText(item.getTitle());
int numImages = item.getImages().size();
if (numImages > 0) {
holder.placeholder.setVisivility(View.VISIBLE);
ImageView image = (ImageView)holder.placeholder.findViewById(R.id.image);
Glide.with(context)
.load("http://www.website.com/test.png")
.fitCenter()
.into(image);
}else{
holder.placeholder.setVisibility(View.INVISIBLE);
}
}
Sometimes when using RecyclerView, a View may be re-used and retain the size from a previous position that will be changed for the current position. To handle those cases, you can create a new [ViewTarget and pass in true for waitForLayout]:
#Override
public void onBindViewHolder(VH holder, int position) {
Glide.with(fragment)
.load(urls.get(position))
.into(new DrawableImageViewTarget(holder.imageView,/*waitForLayout=*/ true));
https://bumptech.github.io/glide/doc/targets.html
I also had the same problem and ended with below solution and it working fine for me..
Have your hands on this solution might be work for you too (Put below code in your adapter class)-
If you are using Kotlin -
override fun getItemId(position: Int): Long {
return position.toLong()
}
override fun getItemViewType(position: Int): Int {
return position
}
If you are using JAVA -
#Override
public long getItemId(int position) {
return position;
}
#Override
public int getItemViewType(int position) {
return position;
}
This works for me in onBindViewHolder!
if(!m.getPicture().isEmpty())
{
holder.setIsRecyclable(false);
Picasso.with(holder.profile_pic.getContext()).load(m.getPicture()).placeholder(R.mipmap.ic_launcher_round).into(holder.profile_pic);
Animation fadeOut = new AlphaAnimation(0, 1);
fadeOut.setInterpolator(new AccelerateInterpolator());
fadeOut.setDuration(1000);
holder.profile_pic.startAnimation(fadeOut);
}
else
{
holder.setIsRecyclable(true);
}
I was having same issue I solved by writing holder.setIsRecyclable(false).Worked for me.
#Override
public void onBindViewHolder(#NonNull RecylerViewHolder holder, int position) {
NewsFeed currentFeed = newsFeeds.get(position);
holder.textView.setText(currentFeed.getNewsTitle());
holder.sectionView.setText(currentFeed.getNewsSection());
if(currentFeed.getImageId() == "NOIMG") {
holder.setIsRecyclable(false);
Log.v("ImageLoad","Image not loaded");
} else {
Picasso.get().load(currentFeed.getImageId()).into(holder.imageView);
Log.v("ImageLoad","Image id "+ currentFeed.getImageId());
}
holder.dateView.setText(getModifiedDate(currentFeed.getDate()));
}
override fun getItemId(position: Int): Long {
return position.toLong()
}
override fun getItemViewType(position: Int): Int {
return position
}
This Works for Me
I Had the same issue and i fixed it like this:
GOAL : onViewAttachedToWindow
#Override
public void onViewAttachedToWindow(Holder holder) {
super.onViewAttachedToWindow(holder);
StructAllItems sfi = mArrayList.get(position);
if (!sfi.getPicHayatParking().isEmpty()) {
holder.viewFliperMelk.addSlider(new TextSliderView(mContext.getApplicationContext()).image(T.GET_MELK_IMAGE + '/' + sfi.getPicHayatParking() + ".jpg").setScaleType(BaseSliderView.ScaleType.CenterCrop));
}
if (!sfi.getPicSleepRoom().isEmpty()) {
holder.viewFliperMelk.addSlider(new TextSliderView(mContext.getApplicationContext()).image(T.GET_MELK_IMAGE + '/' + sfi.getPicSleepRoom() + ".jpg").setScaleType(BaseSliderView.ScaleType.CenterCrop));
}
if (!sfi.getPicSalonPazirayi().isEmpty()) {
holder.viewFliperMelk.addSlider(new TextSliderView(mContext.getApplicationContext()).image(T.GET_MELK_IMAGE + '/' + sfi.getPicSalonPazirayi() + ".jpg").setScaleType(BaseSliderView.ScaleType.CenterCrop));
}
if (!sfi.getPicNamayeStruct().isEmpty()) {
holder.viewFliperMelk.addSlider(new TextSliderView(mContext.getApplicationContext()).image(T.GET_MELK_IMAGE + '/' + sfi.getPicNamayeStruct() + ".jpg").setScaleType(BaseSliderView.ScaleType.CenterCrop));
}
}
I had a similar issue when getting pictures from the photo gallery and putting them in a recyclerview with GridLayoutManager(never had the issue with Glide). So in the adapter onBindViewHolder use a HashMap or SparseIntArray to put the current hashcode(this is the common thing that the recycled views have in common) and adapter position inside it. Then call your background task and then once it's done and before you set the image, check to see if the hashcode key - which will always have the current adapter position as the value - still has the same value (adapter position) as when you first called the background task.
(Global variable)
private SparseIntArray hashMap = new SparseIntArray();
onBindViewHolder(ViewHolder holder, int position){
holder.imageView.setImageResource(R.drawable.grey_square);
hashMap.put(holder.hashCode(), position);
yourBackgroundTask(ViewHolder holder, int position);
}
yourBackGroundTask(ViewHolder holder, int holderPosition){
do some stuff in the background.....
*if you want to stop to image from downloading / or in my case
fetching the image from MediaStore then do -
if(hashMap.get(holder.hashCode())!=(holderPos)){
return null;
}
- in the background task, before the call to get the
image
onPostExecute{
if(hashMap.get(holder.hashCode())==(holderPosition)){
holder.imageView.setImageBitmap(result);
}
}
}
So i am just providing an extension to this answer since there is not much space to leave it as comment.
After trying out like mentioned in one of above solutions i found out that, the real issue can still be addressed even if you are using a static resource(is not being downloaded and is available locally)
So basically on onBindViewHolder event i just converted the resource to drawable and added it like below :
imageView.setImageDrawable(ContextCompat.getDrawable(context,R.drawable.album_art_unknown));
this way you wont have an empty space on the view while glide/async downloader is loading the actual image from network.
plus looking at that being reloaded every time i also added below code while calling the recycler adapter class;
recyclerView.setItemViewCacheSize(10);
recyclerView.setDrawingCacheEnabled(true);
so by using above way you wont need to set setIsRecyclable(false) which is degrading if you have larger datasets.
By doing this i you will have a flicker free loading of recyclerview of course except for the initial loads.
I would like to say that if you send the ImageView and any load-async command (for instance loading from S3), the recycler view does get confused.
I did set the bitmap null in the onViewRecycled and tested with attach and detach views etc. the issue never went away.
The issue is that if a holderView gets used for image-1, image-10 and stops at the scroll with image-19, what the user sees is image-1, then image-10 and then image-19.
One method that worked for me is to keep a hash_map that helps know what is the latest image that needs to be displayed on that ImageView.
Remember, the holder is recycled, so the hash for that view is persistent.
1- Create this map for storing what image should be displayed,
public static HashMap<Integer, String> VIEW_SYNCHER = new HashMap<Integer, String>();
2- In your Adapter, onBindViewHolder,
String thumbnailCacheKey = "img-url";
GLOBALS.VIEW_SYNCHER.put(holder.thumbnailImage.hashCode(), thumbnailCacheKey);
3- Then you have some async call to make the network call and load the image in the view right ?
In that code after loading the image from S3, you test to make sure what goes into the View,
// The ImageView in the network data loader, get its hash.
int viewCode = iim.imView[0].hashCode();
if (GLOBALS.VIEW_SYNCHER.containsKey(viewCode))
if (GLOBALS.VIEW_SYNCHER.get(viewCode).equals(bitmapKey))
iim.imView[0].setImageBitmap(GLOBALS.BITMAP_CACHE.get(bitmapKey).bitmapData);
So essentially, you make sure what is the last image key that should go into a view, then when you download the image you check to make sure that's the last image URL that goes in that view.
This solution worked for me.

Recyclerview Adapter and Glide - same image every 4-5 rows

I have this problem - just for testing purposes I added ParseFile to one of ParseObject from received list. Instead of showing it only in that row it shows every 4-5 rows, sometimes more, sometimes less. I supspect that recycling view have something to do with this. Strangely, other data (deleted from this example) works fine with position variable.
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
if(parseList.get(position).get("logo") != null){
ParseFile image = (ParseFile) parseList.get(position).get("logo");
String url = image.getUrl();
Glide.with(context)
.load(url)
.placeholder(R.drawable.piwo_48)
.transform(new CircleTransform(context))
.into(holder.imageView);
}
}
The answers here are incorrect, although they're on the right track.
You need to call Glide#clear(), not just set the image drawable to null. If you don't call clear(), an async load completing out of order may still cause view recycling issues. Your code should look like this:
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
if (parseList.get(position).get("logo") != null) {
ParseFile image = (ParseFile) parseList.get(position).get("logo");
String url = image.getUrl();
Glide.with(context)
.load(url)
.placeholder(R.drawable.piwo_48)
.transform(new CircleTransform(context))
.into(holder.imageView);
} else {
// make sure Glide doesn't load anything into this view until told otherwise
Glide.with(context).clear(holder.imageView);
// remove the placeholder (optional); read comments below
holder.imageView.setImageDrawable(null);
}
}
Maybe you need to try something like this
.signature(new StringSignature(String.valueOf(System.currentTimeMillis())))
sample :
Glide.with(context)
.load(url)
.placeholder(R.drawable.progress_animation)
.crossFade()
.signature(new StringSignature(String.valueOf(System.currentTimeMillis())))
.error(R.drawable.image_error_404)
.into(iv);
In RecyclerView each row is recycled with new data. In your code you are setting ImageView only when it's not null and otherwise doing nothing. In this case when it's not null ImageView will show old image since you didn't override for the current object. You can fix this by adding else condition and setting ImageView to null/blank anything.
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
if(parseList.get(position).get("logo") != null){
ParseFile image = (ParseFile) parseList.get(position).get("logo");
String url = image.getUrl();
Glide.with(context)
.load(url)
.placeholder(R.drawable.piwo_48)
.transform(new CircleTransform(context))
.into(holder.imageView);
}
else{
holder.imageView.setImageDrawable(null);
}
}
When "logo" is null, you get the recycled image instead of clearing it. Add this code to properly clear the image:
holder.imageView.setImageDrawable(null);
I think it is because your adapter has
adapter.setHasStableIds(true)
is true and getItemId is not overridden. So recyclerView try to find holder with the same id and reuse it.

Android - How to stop images reloading in Recyclerview when scrolling

I was creating an app for loading images from internet in cards. I am using Recyclerview for listing purpose. For downloading images, I have tried Picasso, universal-image-downloader and other custom methods but everywhere I have this problem:
Whenever I scroll down and up the images in imageview are getting reloaded. I have even kept a condition to check if the imageview contains an image but that also doesn't seem to work or my code may be faulty. But I am not able to find a solution to this problem. Below I have attached the 'onBindViewHolder' function of my code which I think is the problematic part. Here images is a string arraylist containing image urls.
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext())
.inflate(R.layout.default_card, parent, false);
ViewHolder viewHolder;
viewHolder = new ViewHolder(view);
return viewHolder;
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
String url = images.get(position);
if (holder.imgView.getDrawable() != null) {
//Do Nothing
} else {
ImageLoader.getInstance().displayImage(url, holder.imgView);
}
}
You can use .fit() with Picasso. Hope that solves your problem
Picasso.with(persons.get(i).context)
.load(persons.get(i).photoId)
.placeholder(R.drawable.placeholder)
.fit()
.into(personPhoto);
At first, there is a bug in your code - you have to remove the condition from onBindViewHolder. All ImageView instances has to be updated each time they are about to display.
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
String url = images.get(position);
ImageLoader.getInstance().displayImage(url, holder.imgView);
}
The reloading part:
The problem is, that you are probably not using any cache (in-memory, or disk based). I would not elabarote on this a lot, caching of images in collection views is a really common problem and I'm sure a quick StackOverflow search will give you a lot of results.
Just in particular - Universal image does not have caching enabled by default You can turn it on this way.
DisplayImageOptions options = new DisplayImageOptions.Builder()
...
.cacheInMemory(true)
.cacheOnDisk(true)
...
.build();
ImageLoader.getInstance().displayImage(imageUrl, imageView, options); // Incoming options will be used
Or you can set it globally for your application, just check the docs.
You can use this to solve your issue.
mRecyclerView.getRecycledViewPool().setMaxRecycledViews(0, 0);
If you don't want to use Cache, you can use setItemViewCacheSize(size) and mention the size where you don't want to reload. That's it. Recyclerview version 24.0.0

RecyclerView blinking after notifyDatasetChanged()

I have a RecyclerView which loads some data from API, includes an image url and some data, and I use networkImageView to lazy load image.
#Override
public void onResponse(List<Item> response) {
mItems.clear();
for (Item item : response) {
mItems.add(item);
}
mAdapter.notifyDataSetChanged();
mSwipeRefreshLayout.setRefreshing(false);
}
Here is implementation for Adapter:
public void onBindViewHolder(RecyclerView.ViewHolder viewHolder, final int position) {
if (isHeader(position)) {
return;
}
// - get element from your dataset at this position
// - replace the contents of the view with that element
MyViewHolder holder = (MyViewHolder) viewHolder;
final Item item = mItems.get(position - 1); // Subtract 1 for header
holder.title.setText(item.getTitle());
holder.image.setImageUrl(item.getImg_url(), VolleyClient.getInstance(mCtx).getImageLoader());
holder.image.setErrorImageResId(android.R.drawable.ic_dialog_alert);
holder.origin.setText(item.getOrigin());
}
Problem is when we have refresh in the recyclerView, it is blincking for a very short while in the beginning which looks strange.
I just used GridView/ListView instead and it worked as I expected. There were no blincking.
configuration for RecycleView in onViewCreated of my Fragment:
mRecyclerView = (RecyclerView) view.findViewById(R.id.recyclerView);
// use this setting to improve performance if you know that changes
// in content do not change the layout size of the RecyclerView
mRecyclerView.setHasFixedSize(true);
mGridLayoutManager = (GridLayoutManager) mRecyclerView.getLayoutManager();
mGridLayoutManager.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() {
#Override
public int getSpanSize(int position) {
return mAdapter.isHeader(position) ? mGridLayoutManager.getSpanCount() : 1;
}
});
mRecyclerView.setAdapter(mAdapter);
Anyone faced with such a problem? what could be the reason?
Try using stable IDs in your RecyclerView.Adapter
setHasStableIds(true) and override getItemId(int position).
Without stable IDs, after notifyDataSetChanged(), ViewHolders usually assigned to not to same positions. That was the reason of blinking in my case.
You can find a good explanation here.
According to this issue page ....it is the default recycleview item change animation... You can turn it off.. try this
recyclerView.getItemAnimator().setSupportsChangeAnimations(false);
Change in latest version
Quoted from Android developer blog:
Note that this new API is not backward compatible. If you previously
implemented an ItemAnimator, you can instead extend
SimpleItemAnimator, which provides the old API by wrapping the new
API. You’ll also notice that some methods have been entirely removed
from ItemAnimator. For example, if you were calling
recyclerView.getItemAnimator().setSupportsChangeAnimations(false),
this code won’t compile anymore. You can replace it with:
ItemAnimator animator = recyclerView.getItemAnimator();
if (animator instanceof SimpleItemAnimator) {
((SimpleItemAnimator) animator).setSupportsChangeAnimations(false);
}
This simply worked:
recyclerView.getItemAnimator().setChangeDuration(0);
I have the same issue loading image from some urls and then imageView blinks.
Solved by using
notifyItemRangeInserted()
instead of
notifyDataSetChanged()
which avoids to reload those unchanged old datas.
try this to disable the default animation
ItemAnimator animator = recyclerView.getItemAnimator();
if (animator instanceof SimpleItemAnimator) {
((SimpleItemAnimator) animator).setSupportsChangeAnimations(false);
}
this the new way to disable the animation since android support 23
this old way will work for older version of the support library
recyclerView.getItemAnimator().setSupportsChangeAnimations(false)
In Kotlin you can use 'class extension' for RecyclerView:
fun RecyclerView.disableItemAnimator() {
(itemAnimator as? SimpleItemAnimator)?.supportsChangeAnimations = false
}
// sample of using in Activity:
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?): View? {
// ...
myRecyclerView.disableItemAnimator()
// ...
}
Kotlin solution:
(recyclerViewIdFromXML.itemAnimator as SimpleItemAnimator).supportsChangeAnimations = false
Recyclerview uses DefaultItemAnimator as it's default animator.
As you can see from the code below, they change the alpha of the view holder upon item change:
#Override
public boolean animateChange(RecyclerView.ViewHolder oldHolder, RecyclerView.ViewHolder newHolder, int fromX, int fromY, int toX, int toY) {
...
final float prevAlpha = ViewCompat.getAlpha(oldHolder.itemView);
...
ViewCompat.setAlpha(oldHolder.itemView, prevAlpha);
if (newHolder != null) {
....
ViewCompat.setAlpha(newHolder.itemView, 0);
}
...
return true;
}
I wanted to retain the rest of the animations but remove the "flicker" so I cloned DefaultItemAnimator and removed the 3 alpha lines above.
To use the new animator just call setItemAnimator() on your RecyclerView:
mRecyclerView.setItemAnimator(new MyItemAnimator());
Assuming mItems is the collection that backs your Adapter, why are you removing everything and re-adding? You are basically telling it that everything has changed, so RecyclerView rebinds all views than I assume the Image library does not handle it properly where it still resets the View even though it is the same image url. Maybe they had some baked in solution for AdapterView so that it works fine in GridView.
Instead of calling notifyDataSetChanged which will cause re-binding all views, call granular notify events (notify added/removed/moved/updated) so that RecyclerView will rebind only necessary views and nothing will flicker.
Try this in Kotlin
binding.recyclerView.apply {
(itemAnimator as SimpleItemAnimator).supportsChangeAnimations = false
}
In my case, neither any of above nor the answers from other stackoverflow questions having same problems worked.
Well, I was using custom animation each time the item gets clicked, for which I was calling notifyItemChanged(int position, Object Payload) to pass payload to my CustomAnimator class.
Notice, there are 2 onBindViewHolder(...) methods available in RecyclerView Adapter.
onBindViewHolder(...) method having 3 parameters will always be called before onBindViewHolder(...) method having 2 parameters.
Generally, we always override the onBindViewHolder(...) method having 2 parameters and the main root of problem was I was doing the same,
as each time notifyItemChanged(...) gets called, our onBindViewHolder(...) method will be called, in which I was loading my image in ImageView using Picasso, and this was the reason it was loading again regardless of its from memory or from internet. Until loaded, it was showing me the placeholder image, which was the reason of blinking for 1 sec whenever I click on the itemview.
Later, I also override another onBindViewHolder(...) method having 3 parameters. Here I check if the list of payloads is empty, then I return the super class implementation of this method, else if there are payloads, I am just setting the alpha value of the itemView of holder to 1.
And yay I got the solution to my problem after wasting a one full day sadly!
Here's my code for onBindViewHolder(...) methods:
onBindViewHolder(...) with 2 params:
#Override
public void onBindViewHolder(#NonNull RecyclerAdapter.ViewHolder viewHolder, int position) {
Movie movie = movies.get(position);
Picasso.with(context)
.load(movie.getImageLink())
.into(viewHolder.itemView.posterImageView);
}
onBindViewHolder(...) with 3 params:
#Override
public void onBindViewHolder(#NonNull ViewHolder holder, int position, #NonNull List<Object> payloads) {
if (payloads.isEmpty()) {
super.onBindViewHolder(holder, position, payloads);
} else {
holder.itemView.setAlpha(1);
}
}
Here's the code of method I was calling in onClickListener of viewHolder's itemView in onCreateViewHolder(...):
private void onMovieClick(int position, Movie movie) {
Bundle data = new Bundle();
data.putParcelable("movie", movie);
// This data(bundle) will be passed as payload for ItemHolderInfo in our animator class
notifyItemChanged(position, data);
}
Note: You can get this position by calling getAdapterPosition() method of your viewHolder from onCreateViewHolder(...).
I have also overridden getItemId(int position) method as follows:
#Override
public long getItemId(int position) {
Movie movie = movies.get(position);
return movie.getId();
}
and called setHasStableIds(true); on my adapter object in activity.
Hope this helps if none of the answers above work!
In my case there was a much simpler problem, but it can look/feel very much like the problem above. I had converted an ExpandableListView to a RecylerView with Groupie (using Groupie's ExpandableGroup feature). My initial layout had a section like this:
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/hint_list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#android:color/white" />
With layout_height set to "wrap_content" the animation from expanded group to collapsed group felt like it would flash, but it was really just animating from the "wrong" position (even after trying most of the recommendations in this thread).
Anyway, simply changing layout_height to match_parent like this fixed the problem.
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/hint_list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:color/white" />
Hey #Ali it might be late replay. I also faced this issue and solved with below solution, it may help you please check.
LruBitmapCache.java class is created to get image cache size
import android.graphics.Bitmap;
import android.support.v4.util.LruCache;
import com.android.volley.toolbox.ImageLoader.ImageCache;
public class LruBitmapCache extends LruCache<String, Bitmap> implements
ImageCache {
public static int getDefaultLruCacheSize() {
final int maxMemory = (int) (Runtime.getRuntime().maxMemory() / 1024);
final int cacheSize = maxMemory / 8;
return cacheSize;
}
public LruBitmapCache() {
this(getDefaultLruCacheSize());
}
public LruBitmapCache(int sizeInKiloBytes) {
super(sizeInKiloBytes);
}
#Override
protected int sizeOf(String key, Bitmap value) {
return value.getRowBytes() * value.getHeight() / 1024;
}
#Override
public Bitmap getBitmap(String url) {
return get(url);
}
#Override
public void putBitmap(String url, Bitmap bitmap) {
put(url, bitmap);
}
}
VolleyClient.java singleton class [extends Application] added below code
in VolleyClient singleton class constructor add below snippet to initialize the ImageLoader
private VolleyClient(Context context)
{
mCtx = context;
mRequestQueue = getRequestQueue();
mImageLoader = new ImageLoader(mRequestQueue,getLruBitmapCache());
}
I created getLruBitmapCache() method to return LruBitmapCache
public LruBitmapCache getLruBitmapCache() {
if (mLruBitmapCache == null)
mLruBitmapCache = new LruBitmapCache();
return this.mLruBitmapCache;
}
Hope its going to help you.
Try to use the stableId in recycler view. The following article briefly explains it
https://medium.com/#hanru.yeh/recyclerviews-views-are-blinking-when-notifydatasetchanged-c7b76d5149a2
I had similar issue and this worked for me
You can call this method to set size for image cache
private int getCacheSize(Context context) {
final DisplayMetrics displayMetrics = context.getResources().
getDisplayMetrics();
final int screenWidth = displayMetrics.widthPixels;
final int screenHeight = displayMetrics.heightPixels;
// 4 bytes per pixel
final int screenBytes = screenWidth * screenHeight * 4;
return screenBytes * 3;
}
for my application, I had some data changing but I didn't want the entire view to blink.
I solved it by only fading the oldview down 0.5 alpha and starting the newview alpha at 0.5. This created a softer fading transition without making the view disappear completely.
Unfortunately because of private implementations, I couldn't subclass the DefaultItemAnimator in order to make this change so I had to clone the code and make the following changes
in animateChange:
ViewCompat.setAlpha(newHolder.itemView, 0); //change 0 to 0.5f
in animateChangeImpl:
oldViewAnim.alpha(0).setListener(new VpaListenerAdapter() { //change 0 to 0.5f
Using appropriate recyclerview methods to update views will solve this issue
First, make changes in the list
mList.add(item);
or mList.addAll(itemList);
or mList.remove(index);
Then notify using
notifyItemInserted(addedItemIndex);
or
notifyItemRemoved(removedItemIndex);
or
notifyItemRangeChanged(fromIndex, newUpdatedItemCount);
Hope this will help!!
In my case I used SwipeRefresh and RecycleView with viewmodel binding and faced with blinking. Solved with ->
Use submitList() to keep the list updated
because DiffUtils have done the job, otherwise the list reloading entirely
refer to CodeLab https://developer.android.com/codelabs/kotlin-android-training-diffutil-databinding#4
when using livedata I solved it with diffUtil
This is how I combined diffUtill and databinding with my adapter
class ItemAdapter(
private val clickListener: ItemListener
) :
ListAdapter<Item, ItemAdapter.ViewHolder>(ItemDiffCallback()) {
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
holder.bind(clickListener, getItem(position)!!)
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
return ViewHolder.from(parent)
}
class ViewHolder private constructor(val binding: ListItemViewBinding) :
RecyclerView.ViewHolder(binding.root) {
fun bind(
clickListener: ItemListener,
item: Item) {
binding.item = item
binding.clickListener = clickListener
binding.executePendingBindings()
}
companion object {
fun from(parent: ViewGroup): ViewHolder {
val layoutInflater = LayoutInflater.from(parent.context)
val view = ListItemViewBinding
.inflate(layoutInflater, parent, false)
return ViewHolder(view)
}
}
}
class ItemDiffCallback :
DiffUtil.ItemCallback<Item>() {
override fun areItemsTheSame(oldItem: Item, newItem: Item): Boolean {
return oldItem.itemId == newItem.itemId
}
override fun getChangePayload(oldItem: Item, newItem: Item): Any? {
return newItem
}
override fun areContentsTheSame(oldItem: Item, newItem: Item): Boolean {
return oldItem == newItem
}
}
}
class ItemListener(val clickListener: (item: Item) -> Unit) {
fun onClick(item: Item) = clickListener(item)
}
In my case (shared element transition between one image to a higher resolution image), I added some delay to the item decorator in order to make it less noticeable:
(yourRv.itemAnimator as? DefaultItemAnimator)?.changeDuration = 2000
My own issue was a very specific problem which I'm going to share some insight for here, though I don't yet fully understand it.
Basically I had a re-usable fragment with RecyclerView, so that I could have a menu with nested menus. Pick an item in the RecyclerView, and it opens another fragment with more options. All facilitated using the JetPack navigation component and data binding using LiveData in the layout xml.
Anyway, here's how I fixed my issue of items flickering when the RecyclerView changed (although it's worth bearing in mind, this was only the appearance as it was a 'new' RecyclerView each time). To update the LiveData list of items (some viewmodels representing objects for the menu items, in my case) I was using LiveData.value = new items. Changing it to postValue(new items) fixed the issue, though I'm not yet sure why.
I've read up the difference between value (setValue in Java) and PostValue, and I understand they're to do with using the main thread or background threading, and the latter only gets applied one time on the main thread when it's ready. But other than that, I'm not sure why this fixed flickering in my RecyclerView. Maybe someone has some insight? In any case, hopefully this will help someone facing a similar problem to me.
for me recyclerView.setHasFixedSize(true); worked

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