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How to change the background color of only selected view in my recycle view example?only the background color of clicked itemview needs to be changed.
Only one selected item must be displayed with background color change at a time and the rest needs to be as before selecting.
here is my code :
MainActivity
public class MainActivity extends AppCompatActivity {
RecyclerView rv1;
private final String android_versions[]={
"Donut",
"Eclair",
"Froyo",
"Gingerbread",
"Honeycomb",
"Ice Cream Sandwich",
"Jelly Bean",
"KitKat",
"Lollipop",
"Marshmallow"
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initViews();
}
private void initViews(){
rv1=(RecyclerView)findViewById(R.id.recyclerView1);
rv1.setHasFixedSize(true);
RecyclerView.LayoutManager layoutManager=new LinearLayoutManager(getApplicationContext());
rv1.setLayoutManager(layoutManager);
RecyclerDataAdapter rda=new RecyclerDataAdapter(rv1,getApplicationContext(),android_versions);
rv1.setAdapter(rda);
}
}
RecyclerDataadapter
public class RecyclerDataAdapter extends RecyclerView.Adapter<RecyclerDataAdapter.ViewHolder> {
private String android_versionnames[];
private Context context1;
private RecyclerView mRecyclerView;
public RecyclerDataAdapter(RecyclerView recylcerView,Context context,String android_versionnames[]){
this.android_versionnames=android_versionnames;
this.context1=context;
mRecyclerView=recylcerView;
setHasStableIds(true);
System.out.println("Inside dataadapter,Android names : \n ");
for(int i=0;i<android_versionnames.length;i++){
System.out.println("\n"+android_versionnames[i]);
}
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view= LayoutInflater.from(parent.getContext()).inflate(R.layout.row_layout,parent,false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(final ViewHolder holder, int position) {
holder.tv1.setText(android_versionnames[position]);
}
#Override
public int getItemCount() {
return android_versionnames.length;
}
public class ViewHolder extends RecyclerView.ViewHolder {
private TextView tv1;
LinearLayout row_linearlayout;
RecyclerView rv2;
public ViewHolder(final View itemView) {
super(itemView);
tv1=(TextView)itemView.findViewById(R.id.txtView1);
row_linearlayout=(LinearLayout)itemView.findViewById(R.id.row_linrLayout);
rv2=(RecyclerView)itemView.findViewById(R.id.recyclerView1);
/*itemView.setBackgroundColor(0x00000000);//to transparent*/
}
}
}
Finally, I got the answer.
public void onBindViewHolder(final ViewHolder holder, final int position) {
holder.tv1.setText(android_versionnames[position]);
holder.row_linearlayout.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
row_index=position;
notifyDataSetChanged();
}
});
if(row_index==position){
holder.row_linearlayout.setBackgroundColor(Color.parseColor("#567845"));
holder.tv1.setTextColor(Color.parseColor("#ffffff"));
}
else
{
holder.row_linearlayout.setBackgroundColor(Color.parseColor("#ffffff"));
holder.tv1.setTextColor(Color.parseColor("#000000"));
}
}
here 'row_index' is set as '-1' initially
public class ViewHolder extends RecyclerView.ViewHolder {
private TextView tv1;
LinearLayout row_linearlayout;
RecyclerView rv2;
public ViewHolder(final View itemView) {
super(itemView);
tv1=(TextView)itemView.findViewById(R.id.txtView1);
row_linearlayout=(LinearLayout)itemView.findViewById(R.id.row_linrLayout);
rv2=(RecyclerView)itemView.findViewById(R.id.recyclerView1);
}
}
A really simple way to achieve this would be:
//instance variable
List<View>itemViewList = new ArrayList<>();
//OnCreateViewHolderMethod
#Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
final View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_row, parent, false);
final MyViewHolder myViewHolder = new MyViewHolder(itemView);
itemViewList.add(itemView); //to add all the 'list row item' views
//Set on click listener for each item view
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
for(View tempItemView : itemViewList) {
/** navigate through all the itemViews and change color
of selected view to colorSelected and rest of the views to colorDefault **/
if(itemViewList.get(myViewHolder.getAdapterPosition()) == tempItemView) {
tempItemView.setBackgroundResource(R.color.colorSelected);
}
else{
tempItemView.setBackgroundResource(R.color.colorDefault);
}
}
}
});
return myViewHolder;
}
UPDATE
The method above may ruin some default attributes of the itemView, in my case, i was using CardView, and the corner radius of the card was getting removed on click.
Better solution:
//instance variable
List<CardView>cardViewList = new ArrayList<>();
public class MyViewHolder extends RecyclerView.ViewHolder {
CardView cardView; //THIS IS MY ROOT VIEW
...
public MyViewHolder(View view) {
super(view);
cardView = view.findViewById(R.id.row_item_card);
...
}
}
#Override
public void onBindViewHolder(final MyViewHolder holder, int position) {
final OurLocationObject locationObject = locationsList.get(position);
...
cardViewList.add(holder.cardView); //add all the cards to this list
holder.cardView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
//All card color is set to colorDefault
for(CardView cardView : cardViewList){
cardView.setCardBackgroundColor(context.getResources().getColor(R.color.colorDefault));
}
//The selected card is set to colorSelected
holder.cardView.setCardBackgroundColor(context.getResources().getColor(R.color.colorSelected));
}
});
}
UPDATE 2 - IMPORTANT
onBindViewHolder method is called multiple times, and also every time the user scrolls the view out of sight and back in sight!
This will cause the same view to be added to the list multiple times which may cause problems and minor delay in code executions!
To fix this,
change
cardViewList.add(holder.cardView);
to
if (!cardViewList.contains(holder.cardView)) {
cardViewList.add(holder.cardView);
}
I can suggest this solution, which I used in my app. I've placed this code of onTouchListener in my ViewHolder class's constructor. itemView is constructor's argument. Be sure to use return false on this method because this need for working OnClickListener
itemView.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
if(event.getAction() == MotionEvent.ACTION_DOWN)
{
v.setBackgroundColor(Color.parseColor("#f0f0f0"));
}
if (event.getAction() == MotionEvent.ACTION_UP || event.getAction() == MotionEvent.ACTION_CANCEL)
{
v.setBackgroundColor(Color.TRANSPARENT);
}
return false;
}
});
Create Drawable file in Drawable foloder
<item android:drawable="#color/SelectedColor" android:state_pressed="true"></item>
<item android:drawable="#color/SelectedColor" android:state_selected="true"></item>
<item android:drawable="#color/DefultColor"></item>
And in xml file
android:background="#drawable/Drawable file"
In RecyclerView onBindViewHolder
holder.button.setSelected(holder.button.isSelected()?true:false);
Like toggle button
I was able to change the selected view color like this. I think this is the SIMPLE WAY (because you don't have to create instance of layouts and variables.
MAKE SURE YOU DONT GIVE ANY BACKGROUND COLOR INSIDE YOUR RECYCLER VIEW's TAG.
holder.itemView.setBackgroundColor(Color.parseColor("#8DFFFFFF"));
onBindViewHolder() method is given below
#Override
public void onBindViewHolder(#NonNull final MyViewHolder holder, final int position) {
holder.item_1.setText(list_items.get(position).item_1);
holder.item_2.setText(list_items.get(position).item_2);
holder.select_cb.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked){
holder.itemView.setBackgroundColor(Color.parseColor("#8DFFFFFF"));
}else {
holder.itemView.setBackgroundColor(Color.parseColor("#FFFFFF"));
}
}
});
}
What I did to achieve this was actually taking a static variable to store the last clicked position of the item in the RecyclerView and then notify the adapter to update the layout at the position on the last clicked position i.e. notifyItemChanged(lastClickedPosition) whenever a new position is clicked. Calling notifyDataSetChanged() on the whole layout is very costly and unfeasible so doing this for only one position is much better.
Here's the code for this:
public class RecyclerDataAdapter extends RecyclerView.Adapter<RecyclerDataAdapter.ViewHolder> {
private String android_versionnames[];
private Context mContext;
private static lastClickedPosition = -1; // Variable to store the last clicked item position
public RecyclerDataAdapter(Context context,String android_versionnames[]){
this.android_versionnames = android_versionnames;
this.mContext = context;
}
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(mContext).inflate(R.layout.row_layout,
parent, false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(final ViewHolder holder, int position) {
holder.tv1.setText(android_versionnames[position]);
holder.itemView.setBackgroundColor(mContext.getResources().
getColor(R.color.cardview_light_background));
holder.itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
v.setBackgroundColor(mContext.getResources().
getColor(R.color.dark_background));
if (lastClickedPosition != -1)
notifyItemChanged(lastClickedPosition);
lastClickedPosition = position;
}
});
}
#Override
public int getItemCount() {
return android_versionnames.length;
}
public class ViewHolder extends RecyclerView.ViewHolder {
private TextView tv1;
public ViewHolder(final View itemView) {
super(itemView);
tv1=(TextView)itemView.findViewById(R.id.txtView1);
}
}
}
So we will be actually updating only the intended item and not re-running unnecessary updates to the items which have not even been changed.
If you use kotlin, it's really simple.
In your RecyclerAdapter class
userV.invalidateRecycler()
holder.card_User.setCardBackgroundColor(Color.parseColor("#3eb1ae").withAlpha(60))
In your fragment or Activity
override fun invalidateRecycler() {
if (v1.recyclerCompanies.childCount > 0) {
v1.recyclerCompanies.childrenRecursiveSequence().iterator().forEach { card ->
if (card is CardView) {
card.setCardBackgroundColor(Color.WHITE)
}
}
}
}
There is a very simple solution to this, you don't have to work in the adapter. To change the background of a clicked item in the RecyclerView you need to catch the click in the adapter using an iterface:
interface ItemClickListener {
fun onItemClickListener(item: Item, position: Int)
}
When we click we will get the item and the items position. In our bind function in the adapter we will set the on click listener:
container.setOnClickListener {
onClickListener.onItemClickListener(item, position)
}
In your activity you will then implement this interface:
class MainActivity : AppCompatActivity(), ItemAdapter.ItemClickListener {
Next we need to implement the background changing logic on item click. The logic is this: when the user clicks on an item, we check if the background on the clicked item is white (the item is not previously clicked) and if this condition is true, we change the background on all of the items in the RecyclerView to white (to invalidate previously clicked and marked items if there are any) and then change the background color of the clicked item to teal to mark it. And if the background of the clicked item is teal (which means the user clicks again on the same previously marked item), we change the background color on all of the items to white. First we will need to get our item background color as a ColorDrawable. We will use an iterator function to go through all of the items (children) of the RecyclerView and forEach() function to change the background on everyone of them. This method will look like this:
override fun onItemClickListener(item: Item, position: Int) {
val itemBackground: ColorDrawable =
binding.recycler[position].background as ColorDrawable
if (itemBackground.color == ContextCompat.getColor(this, R.color.white)) {
binding.recycler.children.iterator().forEach { item ->
item.setBackgroundColor(
ContextCompat.getColor(
this,
R.color.white
)
)
}
binding.recycler[position].setBackgroundColor(
ContextCompat.getColor(this, R.color.teal_200)
)
} else {
binding.recycler.children.iterator().forEach { item ->
item.setBackgroundColor(
ContextCompat.getColor(
this,
R.color.white
)
)
}
}
}
So now you change the background on item click, if you click the same item, you will change the background back to what it was before.
My solution:
public static class SimpleItemRecyclerViewAdapter
extends RecyclerView.Adapter<SimpleItemRecyclerViewAdapter.ViewHolder> {
private final MainActivity mParentActivity;
private final List<DummyContent.DummyItem> mValues;
private final boolean mTwoPane;
private static int lastClickedPosition=-1;
**private static View viewOld=null;**
private final View.OnClickListener mOnClickListener = new View.OnClickListener() {
#Override
public void onClick(View view) {
DummyContent.DummyItem item = (DummyContent.DummyItem) view.getTag();
if (mTwoPane) {
Bundle arguments = new Bundle();
arguments.putString(ItemDetailFragment.ARG_ITEM_ID, item.id);
ItemDetailFragment fragment = new ItemDetailFragment();
fragment.setArguments(arguments);
mParentActivity.getSupportFragmentManager().beginTransaction()
.replace(R.id.item_detail_container, fragment)
.commit();
} else {
Context context = view.getContext();
Intent intent = new Intent(context, ItemDetailActivity.class);
intent.putExtra(ItemDetailFragment.ARG_ITEM_ID, item.id);
context.startActivity(intent);
}
**view.setBackgroundColor(mParentActivity.getResources().getColor(R.color.SelectedColor));
if(viewOld!=null)
viewOld.setBackgroundColor(mParentActivity.getResources().getColor(R.color.DefaultColor));
viewOld=view;**
}
};
viewOld is null at the beginning, then points to the last selected view.
With onClick you change the background of the selected view and redefine the background of the penultimate view selected.
Simple and functional.
In your adapter class make Integer variable as index and assign it to "0" (if you want to select 1st item by default, if not assign "-1").Then on your onBindViewHolder method,
#Override
public void onBindViewHolder(#NonNull final ViewHolder holder, final int position) {
holder.texttitle.setText(listTitle.get(position));
holder.itemView.setTag(listTitle.get(position));
holder.texttitle.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
index = position;
notifyDataSetChanged();
}
});
if (index == position)
holder.texttitle.setTextColor(mContext.getResources().getColor(R.color.selectedColor));
else
holder.texttitle.setTextColor(mContext.getResources().getColor(R.color.unSelectedColor));
}
Thats it and you are good to go.in If condition true section place your selected color or what ever you need, and else section place unselected color or what ever.
Calling Notifydatasetchanged May be expensive when you need to change one item We can overcome by saving the old position and call notifyItemChanged
var old_postion=-1
public void onBindViewHolder(final ViewHolder holder, final int position) {
holder.tv1.setText(android_versionnames[position]);
holder.row_linearlayout.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
notifyItemChanged(old_position)
//After item change happens set the old_postion as current position
old_position=position
}
});
if(old_position==position){
holder.row_linearlayout.setBackgroundColor(Color.parseColor("#567845"));
holder.tv1.setTextColor(Color.parseColor("#ffffff"));
}
else
{
holder.row_linearlayout.setBackgroundColor(Color.parseColor("#ffffff"));
holder.tv1.setTextColor(Color.parseColor("#000000"));
}
}
Create a selector into Drawable folder:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true">
<shape>
<solid android:color="#color/blue" />
</shape>
</item>
<item android:state_pressed="false">
<shape>
<solid android:color="#android:color/transparent" />
</shape>
</item>
</selector>
Add the property into your xml (where you declare the RecyclerView):
android:background="#drawable/selector"
Add click listener for item view in .onBindViewHolder() of your RecyclerView's adapter. get currently selected position and change color by .setBackground() for previously selected and current item
Most Simpler Way From My Side is to Add a variable in adapterPage as last Clicked Position.
in onBindViewHolder paste this code which checks for last stored position matched with loading positions
Constants is the class where i declare my global variables
if(Constants.LAST_SELECTED_POSITION_SINGLE_PRODUCT == position) {
//change the view background here
holder.colorVariantThumb.setBackgroundResource(R.drawable.selected_background);
}
//on view click you store the position value and notifyItemRangeChanged will
// call the onBindViewHolder and will check the condition
holder.itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view){
Constants.LAST_SELECTED_POSITION_SINGLE_PRODUCT=position;
notifyItemRangeChanged(0, mColorVariants.size());
}
});
I managed to do this from my Activity where i'm setting my Rv and not from the adapter
If someone need to do something similar here's the code
In this case the color changes on a logClick
#Override
public void onLongClick(View view, int position) {
Toast.makeText(UltimasConsultasActivity.this, "Item agregado a la lista de mails",
Toast.LENGTH_SHORT).show();
sendMultipleMails.setVisibility(View.VISIBLE);
valueEmail.setVisibility(View.VISIBLE);
itemsSeleccionados.setVisibility(View.VISIBLE);
listaEmails.add(superListItems.get(position));
listaItems ="";
NameOfyourRecyclerInActivity.findViewHolderForAdapterPosition(position).NameOfYourViewInTheViewholder.setBackgroundColor((Color.parseColor("#336F0D")));
for(int itemsSelect = 0; itemsSelect <= listaEmails.size() -1; itemsSelect++){
listaItems += "*"+listaEmails.get(itemsSelect).getDescripcion() + "\n";
}
itemsSeleccionados.setText("Items Seleccionados : "+ "\n" + listaItems);
}
}));
My Solution
With my solution I'm not using notifyDataSetChanged(), because annoying whenever item is clicked, all the items from list got refreshed. To tackle this problem, I used notifyItemChanged(position); This will only change the selected item.
Below I have added the code of my omBindViewHolder.
private int previousPosition = -1;
private SingleViewItemBinding previousView;
#Override
public void onBindViewHolder(#NonNull final ItemViewHolder holder, final int position) {
holder.viewBinding.setItem(itemList.get(position));
holder.viewBinding.rlContainerMain.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
clickRecyclerView.clickRecyclerItem(position, 0);
previousPosition = position;
notifyItemChanged(position);
if(previousView != null){
previousView.rlContainerMain.setBackgroundColor(
ContextCompat.getColor(context, R.color.colorGrayLight));
}
}
});
if(position == previousPosition){
previousView = holder.viewBinding;
holder.viewBinding.rlContainerMain.setBackgroundColor(
ContextCompat.getColor(context, R.color.colorPrimary));
}
else {
holder.viewBinding.rlContainerMain.setBackgroundColor(
ContextCompat.getColor(context, R.color.colorGrayLight));
}
}
in the Kotlin you can do this simply:
all you need is to create a static variable like this:
companion object {
var last_position = 0
}
then in your onBindViewHolder add this code:
holder.item.setOnClickListener{
holder.item.setBackgroundResource(R.drawable.selected_item)
notifyItemChanged(last_position)
last_position=position
}
which item is the child of recyclerView which you want to change its background after clicking on it.
I made this implementation in kotlin I thing is not very efficient but works
ivIsSelected is a ImageView that represent in my case a check mark
var selectedItems = mutableListOf<Int>(-1)
override fun onBindViewHolder(holder: ContactViewHolder, position: Int) {
// holder.setData(ContactViewModel, position) // I'm passing this to the ViewHolder
holder.itemView.setBackgroundColor(Color.WHITE)
holder.itemView.ivIsSelected.visibility = INVISIBLE
selectedItems.forEach {
if (it == position) {
holder.itemView.setBackgroundColor(Color.argb(45, 0, 255, 43))
holder.itemView.ivIsSelected.visibility = VISIBLE
}
}
holder.itemView.setOnClickListener { it ->
it.setBackgroundColor(Color.BLUE)
selectedItems.add(position)
selectedItems.forEach { selectedItem -> // this forEach is required to refresh all the list
notifyItemChanged(selectedItem)
}
}
}
A faster and simpler way is saving the previous View element selected, so you don't have to use notifyDataSetChanged() or notifyItemChanged(position).
First, add an instance variable inside your Adapter (RecyclerDataAdapter):
View prevElement;
Then, inside your function onClick() (or in my case the lambda function version) you insert this:
holder.itemView.setOnClickListener(v -> {
// CODE TO INSERT
if (prevElement != null)
prevElement.setBackgroundColor(Color.TRANSPARENT);
v.setBackgroundColor(R.color.selected);
prevElement = v;
// DO SOMETHING
...
});
As you can see, the first thing done is checking if the prevElement is not null (an element was clicked before this), so we change its background color to Color.TRANSPARENT (even if it's the same element clicked twice). Then, we set the background color of the View element clicked (v) is changed to R.color.selected. Finally set the element clicked to the prevElement variable, so it can be modified in the next click action.
The response from #Sudhanshu Vohra above was the best in my case and much simpler.
I did minor changes to handle the new selection and previous selection to adjust the display.
I modified it as:
//Handle selected item and previous selection
if (lastSelectedIndex != -1) {
notifyItemChanged(lastSelectedIndex);
}
notifyItemChanged(bindingAdapterPosition);
lastSelectedIndex = bindingAdapterPosition;
Now I refresh only two items, rather than the entire list and it works like a charm. Thank you.
I got it like this
public void onClick(View v){
v.findViewById(R.id.textView).setBackgroundColor(R.drawable.selector_row);
}
Thanks
я не знаю на сколько это поможет но я типа так сделал:) в адаптере #Override public void onBindViewHolder(#NonNull NoteViewHolder holder, int position) { holder.bind(sortedList.get(position)); holder.itemView.setBackgroundResource(R.drawable.bacground_button); }
How to change the background color of only selected view in my recycle view example?only the background color of clicked itemview needs to be changed.
Only one selected item must be displayed with background color change at a time and the rest needs to be as before selecting.
here is my code :
MainActivity
public class MainActivity extends AppCompatActivity {
RecyclerView rv1;
private final String android_versions[]={
"Donut",
"Eclair",
"Froyo",
"Gingerbread",
"Honeycomb",
"Ice Cream Sandwich",
"Jelly Bean",
"KitKat",
"Lollipop",
"Marshmallow"
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initViews();
}
private void initViews(){
rv1=(RecyclerView)findViewById(R.id.recyclerView1);
rv1.setHasFixedSize(true);
RecyclerView.LayoutManager layoutManager=new LinearLayoutManager(getApplicationContext());
rv1.setLayoutManager(layoutManager);
RecyclerDataAdapter rda=new RecyclerDataAdapter(rv1,getApplicationContext(),android_versions);
rv1.setAdapter(rda);
}
}
RecyclerDataadapter
public class RecyclerDataAdapter extends RecyclerView.Adapter<RecyclerDataAdapter.ViewHolder> {
private String android_versionnames[];
private Context context1;
private RecyclerView mRecyclerView;
public RecyclerDataAdapter(RecyclerView recylcerView,Context context,String android_versionnames[]){
this.android_versionnames=android_versionnames;
this.context1=context;
mRecyclerView=recylcerView;
setHasStableIds(true);
System.out.println("Inside dataadapter,Android names : \n ");
for(int i=0;i<android_versionnames.length;i++){
System.out.println("\n"+android_versionnames[i]);
}
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view= LayoutInflater.from(parent.getContext()).inflate(R.layout.row_layout,parent,false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(final ViewHolder holder, int position) {
holder.tv1.setText(android_versionnames[position]);
}
#Override
public int getItemCount() {
return android_versionnames.length;
}
public class ViewHolder extends RecyclerView.ViewHolder {
private TextView tv1;
LinearLayout row_linearlayout;
RecyclerView rv2;
public ViewHolder(final View itemView) {
super(itemView);
tv1=(TextView)itemView.findViewById(R.id.txtView1);
row_linearlayout=(LinearLayout)itemView.findViewById(R.id.row_linrLayout);
rv2=(RecyclerView)itemView.findViewById(R.id.recyclerView1);
/*itemView.setBackgroundColor(0x00000000);//to transparent*/
}
}
}
Finally, I got the answer.
public void onBindViewHolder(final ViewHolder holder, final int position) {
holder.tv1.setText(android_versionnames[position]);
holder.row_linearlayout.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
row_index=position;
notifyDataSetChanged();
}
});
if(row_index==position){
holder.row_linearlayout.setBackgroundColor(Color.parseColor("#567845"));
holder.tv1.setTextColor(Color.parseColor("#ffffff"));
}
else
{
holder.row_linearlayout.setBackgroundColor(Color.parseColor("#ffffff"));
holder.tv1.setTextColor(Color.parseColor("#000000"));
}
}
here 'row_index' is set as '-1' initially
public class ViewHolder extends RecyclerView.ViewHolder {
private TextView tv1;
LinearLayout row_linearlayout;
RecyclerView rv2;
public ViewHolder(final View itemView) {
super(itemView);
tv1=(TextView)itemView.findViewById(R.id.txtView1);
row_linearlayout=(LinearLayout)itemView.findViewById(R.id.row_linrLayout);
rv2=(RecyclerView)itemView.findViewById(R.id.recyclerView1);
}
}
A really simple way to achieve this would be:
//instance variable
List<View>itemViewList = new ArrayList<>();
//OnCreateViewHolderMethod
#Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
final View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_row, parent, false);
final MyViewHolder myViewHolder = new MyViewHolder(itemView);
itemViewList.add(itemView); //to add all the 'list row item' views
//Set on click listener for each item view
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
for(View tempItemView : itemViewList) {
/** navigate through all the itemViews and change color
of selected view to colorSelected and rest of the views to colorDefault **/
if(itemViewList.get(myViewHolder.getAdapterPosition()) == tempItemView) {
tempItemView.setBackgroundResource(R.color.colorSelected);
}
else{
tempItemView.setBackgroundResource(R.color.colorDefault);
}
}
}
});
return myViewHolder;
}
UPDATE
The method above may ruin some default attributes of the itemView, in my case, i was using CardView, and the corner radius of the card was getting removed on click.
Better solution:
//instance variable
List<CardView>cardViewList = new ArrayList<>();
public class MyViewHolder extends RecyclerView.ViewHolder {
CardView cardView; //THIS IS MY ROOT VIEW
...
public MyViewHolder(View view) {
super(view);
cardView = view.findViewById(R.id.row_item_card);
...
}
}
#Override
public void onBindViewHolder(final MyViewHolder holder, int position) {
final OurLocationObject locationObject = locationsList.get(position);
...
cardViewList.add(holder.cardView); //add all the cards to this list
holder.cardView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
//All card color is set to colorDefault
for(CardView cardView : cardViewList){
cardView.setCardBackgroundColor(context.getResources().getColor(R.color.colorDefault));
}
//The selected card is set to colorSelected
holder.cardView.setCardBackgroundColor(context.getResources().getColor(R.color.colorSelected));
}
});
}
UPDATE 2 - IMPORTANT
onBindViewHolder method is called multiple times, and also every time the user scrolls the view out of sight and back in sight!
This will cause the same view to be added to the list multiple times which may cause problems and minor delay in code executions!
To fix this,
change
cardViewList.add(holder.cardView);
to
if (!cardViewList.contains(holder.cardView)) {
cardViewList.add(holder.cardView);
}
I can suggest this solution, which I used in my app. I've placed this code of onTouchListener in my ViewHolder class's constructor. itemView is constructor's argument. Be sure to use return false on this method because this need for working OnClickListener
itemView.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
if(event.getAction() == MotionEvent.ACTION_DOWN)
{
v.setBackgroundColor(Color.parseColor("#f0f0f0"));
}
if (event.getAction() == MotionEvent.ACTION_UP || event.getAction() == MotionEvent.ACTION_CANCEL)
{
v.setBackgroundColor(Color.TRANSPARENT);
}
return false;
}
});
Create Drawable file in Drawable foloder
<item android:drawable="#color/SelectedColor" android:state_pressed="true"></item>
<item android:drawable="#color/SelectedColor" android:state_selected="true"></item>
<item android:drawable="#color/DefultColor"></item>
And in xml file
android:background="#drawable/Drawable file"
In RecyclerView onBindViewHolder
holder.button.setSelected(holder.button.isSelected()?true:false);
Like toggle button
I was able to change the selected view color like this. I think this is the SIMPLE WAY (because you don't have to create instance of layouts and variables.
MAKE SURE YOU DONT GIVE ANY BACKGROUND COLOR INSIDE YOUR RECYCLER VIEW's TAG.
holder.itemView.setBackgroundColor(Color.parseColor("#8DFFFFFF"));
onBindViewHolder() method is given below
#Override
public void onBindViewHolder(#NonNull final MyViewHolder holder, final int position) {
holder.item_1.setText(list_items.get(position).item_1);
holder.item_2.setText(list_items.get(position).item_2);
holder.select_cb.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked){
holder.itemView.setBackgroundColor(Color.parseColor("#8DFFFFFF"));
}else {
holder.itemView.setBackgroundColor(Color.parseColor("#FFFFFF"));
}
}
});
}
What I did to achieve this was actually taking a static variable to store the last clicked position of the item in the RecyclerView and then notify the adapter to update the layout at the position on the last clicked position i.e. notifyItemChanged(lastClickedPosition) whenever a new position is clicked. Calling notifyDataSetChanged() on the whole layout is very costly and unfeasible so doing this for only one position is much better.
Here's the code for this:
public class RecyclerDataAdapter extends RecyclerView.Adapter<RecyclerDataAdapter.ViewHolder> {
private String android_versionnames[];
private Context mContext;
private static lastClickedPosition = -1; // Variable to store the last clicked item position
public RecyclerDataAdapter(Context context,String android_versionnames[]){
this.android_versionnames = android_versionnames;
this.mContext = context;
}
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(mContext).inflate(R.layout.row_layout,
parent, false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(final ViewHolder holder, int position) {
holder.tv1.setText(android_versionnames[position]);
holder.itemView.setBackgroundColor(mContext.getResources().
getColor(R.color.cardview_light_background));
holder.itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
v.setBackgroundColor(mContext.getResources().
getColor(R.color.dark_background));
if (lastClickedPosition != -1)
notifyItemChanged(lastClickedPosition);
lastClickedPosition = position;
}
});
}
#Override
public int getItemCount() {
return android_versionnames.length;
}
public class ViewHolder extends RecyclerView.ViewHolder {
private TextView tv1;
public ViewHolder(final View itemView) {
super(itemView);
tv1=(TextView)itemView.findViewById(R.id.txtView1);
}
}
}
So we will be actually updating only the intended item and not re-running unnecessary updates to the items which have not even been changed.
If you use kotlin, it's really simple.
In your RecyclerAdapter class
userV.invalidateRecycler()
holder.card_User.setCardBackgroundColor(Color.parseColor("#3eb1ae").withAlpha(60))
In your fragment or Activity
override fun invalidateRecycler() {
if (v1.recyclerCompanies.childCount > 0) {
v1.recyclerCompanies.childrenRecursiveSequence().iterator().forEach { card ->
if (card is CardView) {
card.setCardBackgroundColor(Color.WHITE)
}
}
}
}
There is a very simple solution to this, you don't have to work in the adapter. To change the background of a clicked item in the RecyclerView you need to catch the click in the adapter using an iterface:
interface ItemClickListener {
fun onItemClickListener(item: Item, position: Int)
}
When we click we will get the item and the items position. In our bind function in the adapter we will set the on click listener:
container.setOnClickListener {
onClickListener.onItemClickListener(item, position)
}
In your activity you will then implement this interface:
class MainActivity : AppCompatActivity(), ItemAdapter.ItemClickListener {
Next we need to implement the background changing logic on item click. The logic is this: when the user clicks on an item, we check if the background on the clicked item is white (the item is not previously clicked) and if this condition is true, we change the background on all of the items in the RecyclerView to white (to invalidate previously clicked and marked items if there are any) and then change the background color of the clicked item to teal to mark it. And if the background of the clicked item is teal (which means the user clicks again on the same previously marked item), we change the background color on all of the items to white. First we will need to get our item background color as a ColorDrawable. We will use an iterator function to go through all of the items (children) of the RecyclerView and forEach() function to change the background on everyone of them. This method will look like this:
override fun onItemClickListener(item: Item, position: Int) {
val itemBackground: ColorDrawable =
binding.recycler[position].background as ColorDrawable
if (itemBackground.color == ContextCompat.getColor(this, R.color.white)) {
binding.recycler.children.iterator().forEach { item ->
item.setBackgroundColor(
ContextCompat.getColor(
this,
R.color.white
)
)
}
binding.recycler[position].setBackgroundColor(
ContextCompat.getColor(this, R.color.teal_200)
)
} else {
binding.recycler.children.iterator().forEach { item ->
item.setBackgroundColor(
ContextCompat.getColor(
this,
R.color.white
)
)
}
}
}
So now you change the background on item click, if you click the same item, you will change the background back to what it was before.
My solution:
public static class SimpleItemRecyclerViewAdapter
extends RecyclerView.Adapter<SimpleItemRecyclerViewAdapter.ViewHolder> {
private final MainActivity mParentActivity;
private final List<DummyContent.DummyItem> mValues;
private final boolean mTwoPane;
private static int lastClickedPosition=-1;
**private static View viewOld=null;**
private final View.OnClickListener mOnClickListener = new View.OnClickListener() {
#Override
public void onClick(View view) {
DummyContent.DummyItem item = (DummyContent.DummyItem) view.getTag();
if (mTwoPane) {
Bundle arguments = new Bundle();
arguments.putString(ItemDetailFragment.ARG_ITEM_ID, item.id);
ItemDetailFragment fragment = new ItemDetailFragment();
fragment.setArguments(arguments);
mParentActivity.getSupportFragmentManager().beginTransaction()
.replace(R.id.item_detail_container, fragment)
.commit();
} else {
Context context = view.getContext();
Intent intent = new Intent(context, ItemDetailActivity.class);
intent.putExtra(ItemDetailFragment.ARG_ITEM_ID, item.id);
context.startActivity(intent);
}
**view.setBackgroundColor(mParentActivity.getResources().getColor(R.color.SelectedColor));
if(viewOld!=null)
viewOld.setBackgroundColor(mParentActivity.getResources().getColor(R.color.DefaultColor));
viewOld=view;**
}
};
viewOld is null at the beginning, then points to the last selected view.
With onClick you change the background of the selected view and redefine the background of the penultimate view selected.
Simple and functional.
In your adapter class make Integer variable as index and assign it to "0" (if you want to select 1st item by default, if not assign "-1").Then on your onBindViewHolder method,
#Override
public void onBindViewHolder(#NonNull final ViewHolder holder, final int position) {
holder.texttitle.setText(listTitle.get(position));
holder.itemView.setTag(listTitle.get(position));
holder.texttitle.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
index = position;
notifyDataSetChanged();
}
});
if (index == position)
holder.texttitle.setTextColor(mContext.getResources().getColor(R.color.selectedColor));
else
holder.texttitle.setTextColor(mContext.getResources().getColor(R.color.unSelectedColor));
}
Thats it and you are good to go.in If condition true section place your selected color or what ever you need, and else section place unselected color or what ever.
Calling Notifydatasetchanged May be expensive when you need to change one item We can overcome by saving the old position and call notifyItemChanged
var old_postion=-1
public void onBindViewHolder(final ViewHolder holder, final int position) {
holder.tv1.setText(android_versionnames[position]);
holder.row_linearlayout.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
notifyItemChanged(old_position)
//After item change happens set the old_postion as current position
old_position=position
}
});
if(old_position==position){
holder.row_linearlayout.setBackgroundColor(Color.parseColor("#567845"));
holder.tv1.setTextColor(Color.parseColor("#ffffff"));
}
else
{
holder.row_linearlayout.setBackgroundColor(Color.parseColor("#ffffff"));
holder.tv1.setTextColor(Color.parseColor("#000000"));
}
}
Create a selector into Drawable folder:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true">
<shape>
<solid android:color="#color/blue" />
</shape>
</item>
<item android:state_pressed="false">
<shape>
<solid android:color="#android:color/transparent" />
</shape>
</item>
</selector>
Add the property into your xml (where you declare the RecyclerView):
android:background="#drawable/selector"
Add click listener for item view in .onBindViewHolder() of your RecyclerView's adapter. get currently selected position and change color by .setBackground() for previously selected and current item
Most Simpler Way From My Side is to Add a variable in adapterPage as last Clicked Position.
in onBindViewHolder paste this code which checks for last stored position matched with loading positions
Constants is the class where i declare my global variables
if(Constants.LAST_SELECTED_POSITION_SINGLE_PRODUCT == position) {
//change the view background here
holder.colorVariantThumb.setBackgroundResource(R.drawable.selected_background);
}
//on view click you store the position value and notifyItemRangeChanged will
// call the onBindViewHolder and will check the condition
holder.itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view){
Constants.LAST_SELECTED_POSITION_SINGLE_PRODUCT=position;
notifyItemRangeChanged(0, mColorVariants.size());
}
});
I managed to do this from my Activity where i'm setting my Rv and not from the adapter
If someone need to do something similar here's the code
In this case the color changes on a logClick
#Override
public void onLongClick(View view, int position) {
Toast.makeText(UltimasConsultasActivity.this, "Item agregado a la lista de mails",
Toast.LENGTH_SHORT).show();
sendMultipleMails.setVisibility(View.VISIBLE);
valueEmail.setVisibility(View.VISIBLE);
itemsSeleccionados.setVisibility(View.VISIBLE);
listaEmails.add(superListItems.get(position));
listaItems ="";
NameOfyourRecyclerInActivity.findViewHolderForAdapterPosition(position).NameOfYourViewInTheViewholder.setBackgroundColor((Color.parseColor("#336F0D")));
for(int itemsSelect = 0; itemsSelect <= listaEmails.size() -1; itemsSelect++){
listaItems += "*"+listaEmails.get(itemsSelect).getDescripcion() + "\n";
}
itemsSeleccionados.setText("Items Seleccionados : "+ "\n" + listaItems);
}
}));
My Solution
With my solution I'm not using notifyDataSetChanged(), because annoying whenever item is clicked, all the items from list got refreshed. To tackle this problem, I used notifyItemChanged(position); This will only change the selected item.
Below I have added the code of my omBindViewHolder.
private int previousPosition = -1;
private SingleViewItemBinding previousView;
#Override
public void onBindViewHolder(#NonNull final ItemViewHolder holder, final int position) {
holder.viewBinding.setItem(itemList.get(position));
holder.viewBinding.rlContainerMain.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
clickRecyclerView.clickRecyclerItem(position, 0);
previousPosition = position;
notifyItemChanged(position);
if(previousView != null){
previousView.rlContainerMain.setBackgroundColor(
ContextCompat.getColor(context, R.color.colorGrayLight));
}
}
});
if(position == previousPosition){
previousView = holder.viewBinding;
holder.viewBinding.rlContainerMain.setBackgroundColor(
ContextCompat.getColor(context, R.color.colorPrimary));
}
else {
holder.viewBinding.rlContainerMain.setBackgroundColor(
ContextCompat.getColor(context, R.color.colorGrayLight));
}
}
in the Kotlin you can do this simply:
all you need is to create a static variable like this:
companion object {
var last_position = 0
}
then in your onBindViewHolder add this code:
holder.item.setOnClickListener{
holder.item.setBackgroundResource(R.drawable.selected_item)
notifyItemChanged(last_position)
last_position=position
}
which item is the child of recyclerView which you want to change its background after clicking on it.
I made this implementation in kotlin I thing is not very efficient but works
ivIsSelected is a ImageView that represent in my case a check mark
var selectedItems = mutableListOf<Int>(-1)
override fun onBindViewHolder(holder: ContactViewHolder, position: Int) {
// holder.setData(ContactViewModel, position) // I'm passing this to the ViewHolder
holder.itemView.setBackgroundColor(Color.WHITE)
holder.itemView.ivIsSelected.visibility = INVISIBLE
selectedItems.forEach {
if (it == position) {
holder.itemView.setBackgroundColor(Color.argb(45, 0, 255, 43))
holder.itemView.ivIsSelected.visibility = VISIBLE
}
}
holder.itemView.setOnClickListener { it ->
it.setBackgroundColor(Color.BLUE)
selectedItems.add(position)
selectedItems.forEach { selectedItem -> // this forEach is required to refresh all the list
notifyItemChanged(selectedItem)
}
}
}
A faster and simpler way is saving the previous View element selected, so you don't have to use notifyDataSetChanged() or notifyItemChanged(position).
First, add an instance variable inside your Adapter (RecyclerDataAdapter):
View prevElement;
Then, inside your function onClick() (or in my case the lambda function version) you insert this:
holder.itemView.setOnClickListener(v -> {
// CODE TO INSERT
if (prevElement != null)
prevElement.setBackgroundColor(Color.TRANSPARENT);
v.setBackgroundColor(R.color.selected);
prevElement = v;
// DO SOMETHING
...
});
As you can see, the first thing done is checking if the prevElement is not null (an element was clicked before this), so we change its background color to Color.TRANSPARENT (even if it's the same element clicked twice). Then, we set the background color of the View element clicked (v) is changed to R.color.selected. Finally set the element clicked to the prevElement variable, so it can be modified in the next click action.
The response from #Sudhanshu Vohra above was the best in my case and much simpler.
I did minor changes to handle the new selection and previous selection to adjust the display.
I modified it as:
//Handle selected item and previous selection
if (lastSelectedIndex != -1) {
notifyItemChanged(lastSelectedIndex);
}
notifyItemChanged(bindingAdapterPosition);
lastSelectedIndex = bindingAdapterPosition;
Now I refresh only two items, rather than the entire list and it works like a charm. Thank you.
I got it like this
public void onClick(View v){
v.findViewById(R.id.textView).setBackgroundColor(R.drawable.selector_row);
}
Thanks
я не знаю на сколько это поможет но я типа так сделал:) в адаптере #Override public void onBindViewHolder(#NonNull NoteViewHolder holder, int position) { holder.bind(sortedList.get(position)); holder.itemView.setBackgroundResource(R.drawable.bacground_button); }
I have an adapter that extends RecycleView.Adapter and I am running into an issue where scrolling will cause views to change their visibility. I use visibility of views to simulate a collapsed or de-collapsed state, and scrolling is somehow resetting the visibility of the final and first items only from a list of 15 items.
The items begin with a Title displayed with TextView. Clicking on that item will de-collapse that item to reveal the Description text also displayed with TextView (I just set the visibility of the view that has the Description text to VISIBLE). Clicking the Description text will collapse that item (visibility set to GONE) to reveal only the initial Title text.
How come when I scroll to my last item, it de-collapses even when not pressed. Additionally, if I have my first item de-collapsed scrolling to the bottom will collapse the first item. Here is my setup.
public class TextAdapter extends RecyclerView.Adapter<TextAdapter.ViewHolder> {
private static final String TAG = TextAdapter.class.getSimpleName();
private Context mContext;
private ArrayList<TextDescription> alTextDesc;
public TextAdapter(Context context, ArrayList<TextDescription> textDesc) {
mContext = context;
alTextDesc = textDesc;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(mContext).inflate(R.layout.ui_item_text_desc, parent, false);
return new ViewHolder(v);
}
#Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
final TextDescription textDesc = alTextDesc.get(position);
holder.llParent.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
textDesc.isExpanded = !textDesc.isExpanded;
setExpanded(holder, textDesc);
}
});
setExpanded(holder, textDesc);
}
#Override
public int getItemCount() {
return alTextDesc.size();
}
#Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
super.onAttachedToRecyclerView(recyclerView);
}
private static void setExpanded(ViewHolder holder, TextDescription textDesc) {
if (textDesc != null) {
if (textDesc.isExpanded) {
// display full description
llContent.setVisibility(View.VISIBLE);
} else {
// display title
llContent.setVisibility(View.GONE);
}
}
}
public static class ViewHolder extends RecyclerView.ViewHolder {
LinearLayout llParent;
LinearLayout llContent;
public ViewHolder(View v) {
super(v);
llParent = (LinearLayout) v.findViewById(R.id.ll_parent);
llContent = (LinearLayout) v.findViewById(R.id.ll_content);
}
}
My TextDescription model class is nothing more than a boolean
public boolean isExpanded;
Any suggestions on what I am doing incorrectly? Thank you in advance!
EDIT
I have also tried updating my ArrayList after changing the attribute expanded value and the results are still the same
holder.llParent.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
textDesc.isExpanded = !textDesc.isExpanded;
alTextDesc.set(position, textDesc); //tried to update the list with updated value
setExpanded(holder, textDesc);
}
});
The issue is due to recycling of views.
You need to update your list alTextDesc after you change the expanded flag so that when the views are recycled, you have your flag state saved in the list alTextDesc and it will again collapse/expand based on that saved flag state.
holder.llParent.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
textDesc.isExpanded = !textDesc.isExpanded;//Update the list with the updated object now
setExpanded(holder, textDesc);
}
});
I've implemented an nested ReyclerView (horizontal into vertical) and I wan't to add an click listener for the entire row which is wrapped in a CardView element.
The issue I'm having is that the inside RecyclerView captures all the touch events and the root CardView does not respond to the onClick event.
I've also tried to make the CardView intercept the touch events, but with this approach the ripple effect (in fact any feedback) wasn't working.
Can someone recommend an solution for how to implement a click listener on a row while having nested RecyclerView?
Thank you.
--LE--
This is the current implementation:
fragment layout
<android.support.v7.widget.RecyclerView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/list"
android:name=".NestedRecyclerViewsFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layoutManager="LinearLayoutManager"
tools:context=".NestedRecyclerViewsFragment"
tools:listitem="#layout/fragment_nested_recyclerview_item"
/>
Fragment onCreateView() implementation
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_nested_recyclerview_list, container, false);
// Set the adapter
if (view instanceof RecyclerView) {
Context context = view.getContext();
RecyclerView recyclerView = (RecyclerView) view;
recyclerView.setLayoutManager(new LinearLayoutManager(context, LinearLayoutManager.VERTICAL, false));
recyclerView.setHasFixedSize(true); // Improves performance - as we know the size doesn't change
//Initialize and set the adapter
mAdapter = new RootAdapter(context, mListener);
recyclerView.setAdapter(mAdapter);
final GestureDetector mGestureDetector =
new GestureDetector(view.getContext(), new GestureDetector.SimpleOnGestureListener() {
#Override
public boolean onSingleTapUp(MotionEvent e) {
return true;
}
});
recyclerView.addOnItemTouchListener(new RecyclerView.SimpleOnItemTouchListener() {
//TODO: intercept simple gestures like onClick and/or onLongClick
#Override
public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {
View child = rv.findChildViewUnder(e.getX(), e.getY());
if (child != null && mGestureDetector.onTouchEvent(e)) {
//TODO: handle the intercept??
child.callOnClick();
return true;
}
return super.onInterceptTouchEvent(rv, e);
}
});
recyclerView.setNestedScrollingEnabled(true);
}
return view;
}
**Root Adapter layout **
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="#dimen/row_height"
android:layout_gravity="center_horizontal"
android:layout_margin="#dimen/none"
android:padding="#dimen/none"
app:cardCornerRadius="#dimen/none"
tools:context=".NestedRecyclerViewActivity"
<!-- Simple selector for API < 21 and ripple effect for APi >= 21 -->
android:foreground="#drawable/selector_default"
android:clickable="true"
android:focusable="true"
>
<!-- Horizontal image gallery inside row item -->
<android.support.v7.widget.RecyclerView
android:id="#+id/child_recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
...
</android.support.v7.widget.CardView>
Root Adapter onBindView() implementation:
...
holder.childRecyclerView.setLayoutManager(new LinearLayoutManager(holder.mView.getContext(),
LinearLayoutManager.HORIZONTAL, false));
holder.childRecyclerView.setHasFixedSize(true); // We know the image don't change size
holder.childRecyclerView.setAdapter(new ChildAdapter(items));
...
Root Adapter ViewHolder implementation:
public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
private ItemClickListener mClickListener;
/**
* The whole view - useful if you need to place some touch listener on the entire row.
*/
public final View mView;
/**
* The model associated with this view. - will be updated on bind method
*/
public Object mItem;
#Bind(R.id.child_recycler_view)
RecyclerView childRecyclerView;
...
public ViewHolder(View view) {
super(view);
ButterKnife.bind(this, view);
mView = view;
mView.setOnClickListener(this);
// Set the click listener bound to the fragment or activity
mClickListener = RootAdapter.this;
}
#Override
public void onClick(View v) {
if (null != mClickListener) {
mClickListener.onClick(v, getAdapterPosition());
}
}
}
The inner RecyclerView (the child) is a very simple and standar implementation without any listener set to it.
Although this solution works and I get the click event and the inner RecyclerView scroll works, I encountered the issue where the feedback of the click is not shown.
LE: Solution
My requirements changed a little since I posted this Issue, having to replace the inner RecyclerView with an PagerAdapter, but the solution I implemented should work with the nested RecyclerView also.
Basically I use an custom ItemClickSupport class which will pass the click events back to the parent as soon as they are intercepted:
/**
* Utility class which adds the ability to add Click Support for RecyclerViews without the need to implement click
* listeners into the adapter or in the ViewHolder's implementation.
* <p>
* Use it by simply binding an click listener to the desired RecyclerView.
* <pre><code>
* ItemClickSupport.addTo(mRecyclerView).setOnItemClickListener(new ItemClickSupport.OnItemClickListener() {
* {#literal#}Override
* public void onItemClicked(RecyclerView recyclerView, int position, View v) {
* // Handle the clicked item
* }
* });
* </code></pre>
* </p>
* Based on <a href="http://www.littlerobots.nl/blog/Handle-Android-RecyclerView-Clicks/">Handle-Android-RecyclerView
* -Clicks</a>, <br/><b>Hugo Visser</b>. Which is very similar with the implementation from <a
* href="https://github.com/lucasr/twoway-view">TwoWay-View</a>.
* <p/>
* Created by ionut on 22.03.2016.
*/
public class ItemClickSupport {
private final RecyclerView mRecyclerView;
private OnItemClickListener mOnItemClickListener;
private OnItemLongClickListener mOnItemLongClickListener;
private View.OnClickListener mOnClickListener = new View.OnClickListener() {
#Override
public void onClick(View v) {
if (mOnItemClickListener != null) {
RecyclerView.ViewHolder holder = mRecyclerView.getChildViewHolder(v);
mOnItemClickListener.onItemClicked(mRecyclerView, holder.getAdapterPosition(), v);
}
}
};
private View.OnLongClickListener mOnLongClickListener = new View.OnLongClickListener() {
#Override
public boolean onLongClick(View v) {
if (mOnItemLongClickListener != null) {
RecyclerView.ViewHolder holder = mRecyclerView.getChildViewHolder(v);
return mOnItemLongClickListener.onItemLongClicked(mRecyclerView, holder.getAdapterPosition(), v);
}
return false;
}
};
private RecyclerView.OnChildAttachStateChangeListener mAttachListener =
new RecyclerView.OnChildAttachStateChangeListener() {
#Override
public void onChildViewAttachedToWindow(View view) {
if (mOnItemClickListener != null) {
view.setOnClickListener(mOnClickListener);
}
if (mOnItemLongClickListener != null) {
view.setOnLongClickListener(mOnLongClickListener);
}
}
#Override
public void onChildViewDetachedFromWindow(View view) {
}
};
private ItemClickSupport(RecyclerView recyclerView) {
mRecyclerView = recyclerView;
mRecyclerView.setTag(R.id.item_click_support, this);
mRecyclerView.addOnChildAttachStateChangeListener(mAttachListener);
}
public static ItemClickSupport addTo(RecyclerView view) {
ItemClickSupport support = (ItemClickSupport) view.getTag(R.id.item_click_support);
if (support == null) {
support = new ItemClickSupport(view);
}
return support;
}
public static ItemClickSupport removeFrom(RecyclerView view) {
ItemClickSupport support = (ItemClickSupport) view.getTag(R.id.item_click_support);
if (support != null) {
support.detach(view);
}
return support;
}
public ItemClickSupport setOnItemClickListener(OnItemClickListener listener) {
mOnItemClickListener = listener;
return this;
}
public ItemClickSupport setOnItemLongClickListener(OnItemLongClickListener listener) {
mOnItemLongClickListener = listener;
return this;
}
private void detach(RecyclerView view) {
view.removeOnChildAttachStateChangeListener(mAttachListener);
view.setTag(R.id.item_click_support, null);
}
public interface OnItemClickListener {
void onItemClicked(RecyclerView recyclerView, int position, View v);
void onItemClicked(int position);
}
public interface OnItemLongClickListener {
boolean onItemLongClicked(RecyclerView recyclerView, int position, View v);
}
public static class SimpleOnItemClickListener implements OnItemClickListener {
#Override
public void onItemClicked(int position) {
}
#Override
public void onItemClicked(RecyclerView recyclerView, int position, View v) {
}
}
}
When creating the root adapter, I set the item click listener for it, like this:
ItemClickSupport.addTo(mRecyclerView).setOnItemClickListener(this);
And I also send this listener for the inner adapter through an setter method, like this:
rootAdapter.setOnItemClickListener(this);
rootAdapter is the root adapter, and this is the current fragment I'm in, which implements the ItemClickSupportListener.
In the root adapter, when binding the items and creating the inner adapter, I pass on the item click support listener to the inner adapter, like this:
innerAdapter.setOnItemClickListener(new ItemClickSupport.SimpleOnItemClickListener() {
#Override
public void onItemClicked(int position) {
// Here we pass the click to the parent provided click listener.
// We modify the position with the one of the ViewHolder so that we don't get the
// position of the horizontal RecyclerView adapter - we are interested on the
// vertical item actually.
if (null != mItemClickListener) {
mItemClickListener.onItemClicked(holder.getAdapterPosition());
}
}
});
mItemClickListener is actually the listener set by the fragment through the setter method, described above.
In the inner adapter, when creating the views, I set an click listener on the root of the layout which I inflated and pass that event back to my custom click listener:
// Detect the click events and pass them to any listeners
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (null != mOnItemClickListener) {
mOnItemClickListener.onItemClicked(position);
}
}
});
mOnItemClickListener is actually the item click support which was passed by adapter described above.
Another important thing is to use an FrameLayout for the content of the adapter item views, like this:
<FrameLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:addStatesFromChildren="true"
android:foreground="#drawable/selector_default"
>
The important thing here is the foreground which will use an selector and the flag android:addStatesFromChildren. This is set for the root adapter items.
The inner adapter items should also use an FrameLayout as content view so that we can also set it's selector using foreground attribute:
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:foreground="#drawable/selector_default"
>
This is needed, because when the inner adapter item will capture the click event, the selector to be activated, otherwise the parent should react to the click event and activate it's selector.
try setting click listener to the view in adapter
public class NormalItem extends RecyclerView.ViewHolder {
CardView cardView;
TextView textView;
public NormalItem(View itemView) {
super(itemView);
textView = (TextView) itemView.findViewById(R.id.textView);
cardView = (CardView) itemView.findViewById(R.id.cardview);
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// to perform click on entire row do like this.
}
});
textView.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v){
// perform clicks to views inside the items.
}
}
Update #1
Added hasStableIds(true) and updated Picasso to version 2.5.2.
It does not solve the issue.
Reproduction:
RecyclerView with GridLayoutManager (spanCount = 3).
List items are CardViews with ImageView inside.
When all the items does not fit the screen calling notifyItemChanged on one item causes more than one calls to onBindViewHolder().
One call is for position from notifyItemChanged others for items not visible on the screen.
Issue:
Sometimes the item at position passed to the notifyItemChanged is loaded with an image belonging to an item that is not on the screen (most likely due to recycling of the view holder - although I would assume that if the item remains in place then the passed viewholder would be the same).
I have found Jake's comment on other issue here about calling load() even if the file/uri is null. Image is loaded on every onBindViewHolder here.
Simple sample app:
git clone https://github.com/gswierczynski/recycler-view-grid-layout-with-picasso.git
Tap on an item calls notifyItemChanged with parameter equal to the position of that item.
Code:
public class MainActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment())
.commit();
}
}
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
RecyclerView rv = (RecyclerView) rootView.findViewById(R.id.rv);
rv.setLayoutManager(new GridLayoutManager(getActivity(), 3));
rv.setItemAnimator(new DefaultItemAnimator());
rv.setAdapter(new ImageAdapter());
return rootView;
}
}
private static class ImageAdapter extends RecyclerView.Adapter<ImageViewHolder> implements ClickableViewHolder.OnClickListener {
public static final String TAG = "ImageAdapter";
List<Integer> resourceIds = Arrays.asList(
R.drawable.a0,
R.drawable.a1,
R.drawable.a2,
R.drawable.a3,
R.drawable.a4,
R.drawable.a5,
R.drawable.a6,
R.drawable.a7,
R.drawable.a8,
R.drawable.a9,
R.drawable.a10,
R.drawable.a11,
R.drawable.a12,
R.drawable.a13,
R.drawable.a14,
R.drawable.a15,
R.drawable.a16,
R.drawable.a17,
R.drawable.a18,
R.drawable.a19,
R.drawable.a20);
#Override
public ImageViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item, parent, false);
return new ImageViewHolder(v, this);
}
#Override
public void onBindViewHolder(ImageViewHolder holder, int position) {
Log.d(TAG, "onBindViewHolder position: " + position + " | holder obj:" + holder.toString());
Picasso.with(holder.iv.getContext())
.load(resourceIds.get(position))
.fit()
.centerInside()
.into(holder.iv);
}
#Override
public int getItemCount() {
return resourceIds.size();
}
#Override
public void onClick(View view, int position) {
Log.d(TAG, "onClick position: " + position);
notifyItemChanged(position);
}
#Override
public boolean onLongClick(View view, int position) {
return false;
}
}
private static class ImageViewHolder extends ClickableViewHolder {
public ImageView iv;
public ImageViewHolder(View itemView, OnClickListener onClickListener) {
super(itemView, onClickListener);
iv = (ImageView) itemView.findViewById(R.id.iv);
}
}
}
public class ClickableViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener, View.OnLongClickListener {
OnClickListener onClickListener;
public ClickableViewHolder(View itemView, OnClickListener onClickListener) {
super(itemView);
this.onClickListener = onClickListener;
itemView.setOnClickListener(this);
itemView.setOnLongClickListener(this);
}
#Override
public void onClick(View view) {
onClickListener.onClick(view, getPosition());
}
#Override
public boolean onLongClick(View view) {
return onClickListener.onLongClick(view, getPosition());
}
public static interface OnClickListener {
void onClick(View view, int position);
boolean onLongClick(View view, int position);
}
}
I spent more time than I'd like to admit to work around oddities with RecyclerView and the new adapter that comes with it. The only thing that finally worked for me in terms of correct updates and making sure notifyDataSetChanges and all of its other siblings didn't cause odd behavior was this:
On my adapter, I set
setHasStableIds(true);
In the constructor. I then overrode this method:
#Override
public long getItemId(int position) {
// return a unique id here
}
And made sure that all my items returned a unique id.
How you achieve this is up to you. For me, the data was supplied from my web service in the form of a UUID and I cheated by converting parts of the UUID to long using this:
SomeContent content = _data.get(position);
Long code = Math.abs(content.getContentId().getLeastSignificantBits());
Obviously this is not a very safe approach but chances are it works for my lists which will contain < 1000 items. So far I haven't run into any trouble with it.
What I recommend is to try this approach and see if it works for you. Since you have an array, getting a unique number for you should be simple. Maybe try returning the position of the actual item (and not the position that is passed in the getItemId()) or create a unique long for each of your records and pass that in.
Have you tried calling the mutate() method on the Drawable? See here, for instance.
here a working solution but has graphics glitches when calling notifyDataSetChanged()
holder.iv.post(new Runnable() {
#Override
public void run() {
Picasso.with(holder.iv.getContext())
.load(resourceIds.get(position))
.resize(holder.iv.getWidth(), 0)
.into(holder.iv);
});
it works because at this point image has a width, unfortunately when I need to update all the checkboxes the in the viewholder (like a select all action), and I call notifyDataSetChanged() and the effect is very ugly
still searching for a better solution
edit:
this solution works for me:
holder.iv.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN)
holder.iv.getViewTreeObserver().removeOnGlobalLayoutListener(this);
else
holder.iv.getViewTreeObserver().removeGlobalOnLayoutListener(this);
Picasso.with(holder.iv.getContext())
.load(resourceIds.get(position))
.resize(holder.iv.getMeasuredWidth(), 0)
.into(holder.iv);
}
});