I am making a RecyclerView with Kotlin that will display an image and text. So far the text should be just "Textview" and the image should be one of the images that come with android. The text displays "Textview" the specified number of times but doesn't show the image at all.
I am actually following [this video](https://www.youtube.com/watch?v=jS0buQyfJfs&list=PL0dzCUj1L5JGfHj1lwxOq67zAJV3e1S9S&index=2&t=409s! exactly and run into the problem.
I have changed the cell layout of the image to wrap content and it did not help.
Adapter
class MainAdapter : RecyclerView.Adapter<CustomViewHolder>() {
val vidTitles = listOf("Monday", "Tuesday", "Wednesday", "Thursday", "Friday")
override fun getItemCount(): Int {
return vidTitles.size
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): CustomViewHolder {
//create the view for the rows
val layoutInflater = LayoutInflater.from(parent.context)
val cellForRow = layoutInflater.inflate(R.layout.video_row, parent, false)
return CustomViewHolder(cellForRow)
}
override fun onBindViewHolder(holder: CustomViewHolder, position: Int) {
holder?.view?.videoTitleTextView?.text= vidTitles[position]
}
}
class CustomViewHolder(val view: View): RecyclerView.ViewHolder(view) {
}
RecyclerView's Cell layout
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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="wrap_content">
<ImageView
android:id="#+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#color/colorAccent"
android:contentDescription="avatar image"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:srcCompat="#mipmap/ic_launcher" />
<TextView
android:id="#+id/videoTitleTextView"
android:layout_width="0dp"
android:layout_height="31dp"
android:text="animals"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/imageView" />
</androidx.constraintlayout.widget.ConstraintLayout>
Main Activity
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
//recyclerView_main.setBackgroundColor(Color.CYAN)
recyclerView_main.layoutManager = LinearLayoutManager(this)
recyclerView_main.adapter = MainAdapter()
}
}
I expect it to show both the image and the text; It shows the text but not any image and it doesn't even leave any space for the image.
Change Your Image View as below.
<ImageView
android:id="#+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#color/colorAccent"
android:contentDescription="avatar image"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
android:src="#mipmap/ic_launcher" />
You are using tools:srcCompat which is wrong.
Also Change height of Constraint Layout to wrap_content. Otherwise each item in a Recyclerview is going to take full height of screen.
Tools namespace is used for Compile time behaviour. When you build the app this tools features is removed. Its helps you to preview your view at compile time.
Replace this
tools:srcCompat="#mipmap/ic_launcher"
with this:
android:src="#mipmap/ic_launcher"
Note: Here tools:srcCompat will show only in the preview of Android studio but not in the real device.
For more info check here
When I read your code right, you should see "animals" in your TextViews only :)
This is because in your cell's layout file you set the android:text and not the tools:text attribute.
Just implement your ViewHolder and bind the Views to your model.
If you want only to verify your Views are loaded, you could replace the
tools:srcCompat="#mipmap/ic_launcher"
to
app:srcCompat="#mipmap/ic_launcher"
Related
I'm working on a dynamicViews (not sure if that's the right word for creating a view from a json file).
I'm getting the schema from a JSON file, I've stepped up the recycleView and its adapter, so far so good, each Recycleview item (must or not) contain a number of EditText whose number is unknown in advance, so based on the Json file, I have to inflate inside.
I searched a lot but the similar solution I found for Heterogene Recycleview: the idea was to use separate layout and inflate each of them according to your needs inside onCreateViewHolder but the developer who published the solution knew in advance what is the combination of all possible views and he just switch.
class Adapter_base_Display(private val listener: Display_Fragment,
activity: FragmentActivity ,
liste_display : ArrayList<DisplaySections>)
: RecyclerView.Adapter<Base_DisplayViewHolder>() {
private val activityIns = activity
private val liste_display_Recycle_adapter = liste_display
interface Base_DisplayListener {
fun onClickeddisplay(position: Int)
}
private val items = ArrayList<DisplaySections>()
fun setItems(items: ArrayList<DisplaySections>) {
this.items.clear()
this.items.addAll(items)
notifyDataSetChanged()
}
fun clear() {
val size: Int = items.size
items.clear()
notifyItemRangeRemoved(0, size)
notifyDataSetChanged()
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): Base_DisplayViewHolder {
val binding: ItemDisplayBinding =
ItemDisplayBinding.inflate(LayoutInflater.from(parent.context), parent, false)
return Base_DisplayViewHolder(
binding,
listener as Base_DisplayListener,
activityIns,
parent,
liste_display_Recycle_adapter)
}
override fun getItemCount(): Int = items.size
override fun onBindViewHolder(holder: Base_DisplayViewHolder, position: Int) =
holder.bind(items[position])
}
class Base_DisplayViewHolder(
private val itemBinding: ItemDisplayBinding,
private val listener: Adapter_base_Display.Base_DisplayListener,
private val activityIns: FragmentActivity,
private var parent: ViewGroup,
private val items: ArrayList<DisplaySections>,
) : RecyclerView.ViewHolder(itemBinding.root),
View.OnClickListener {
init {
itemBinding.root.setOnClickListener(this)
}
fun bind(item: DisplaySections) {
itemBinding.textView2.text = item.name
}
override fun onClick(v: View?) {
listener.onClickeddisplay(adapterPosition)
}
}
The EditText I want to inflate multiple time
<EditText
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/edittext_isplay"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="15dp"
android:text="TextView"
android:maxLines="3"
android:textColor="#color/black"
android:textSize="18sp" />
data class DisplaySections(
val id : Int,
val name : String,
val createdAt : String,
val updatedAt : String,
val displayTypeId : Int,
val displayCustomFields : List<DisplayCustomFields> // Contains the elements that will be displayed as EditText
The Base layout-Recycleview Item which is common for all scenarios
<LinearLayout
android:id="#+id/parent_edittext" // ALl EditText container
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:orientation="vertical">
<TextView
android:id="#+id/textView2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="TextView" />
</LinearLayout>
<LinearLayout
android:id="#+id/camera_linear"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:orientation="vertical"
android:visibility="visible">
<ImageView
android:id="#+id/addphoto"
android:layout_width="316dp"
android:layout_height="250dp"
android:layout_gravity="center"
android:layout_marginTop="#dimen/_20sdp"
android:src="#drawable/ajouter_photo"
app:tint="#color/clear_grey" />
<TextView
android:id="#+id/camera_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="Ajouter des photos"
android:textStyle="bold" />
</LinearLayout>
<LinearLayout
android:id="#+id/plus_image"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="#dimen/_20sdp"
android:gravity="center"
android:orientation="vertical"
android:visibility="visible">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/my_photo_recycle"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
</LinearLayout>
I going to post the solution I found.
To solve this problem, we absolutely must use a nested RecyclerView;
As I said above, I want to display a list of items with the same common layout (Imageview + Textview), but the tricky part here is the dynamic part of each item.
For recap:
Each element (may or may not) contain N-1 (EditText), it depends on what it gets from a json file.
if you want to solve this problem by creating multiple Viewholder and switch depending on which "ViewHolderType" you are wrong !, you will just create an infinite layout files, it doesn't make sense.
if you create more than one (EditText) and only change the visibility it may work, but if you get for example 100 EditText from the Json file you are not going to manually create 100 Edittext.
if you want to programmatically generate an EditText, you will affect every item in your view Recycle since you cannot create view inside OnbindViewHolder function.
the only way I found to solve this problem is to create a parent-child RecycleView whenever there is an (EditText) you send it to the child adapter and you keep your parent element safe in the parent adapter.
You can also put a condition (NULL tester) inside the Parent-OnbindViewholder whenever there is no data, you just don't call Child-adapter.
I hope this solution will be useful to anyone who has had this problem, and if you have another solution I will be very happy to test them.
how it should look -
how it looks -
listitem.xml -
<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.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="wrap_content"
app:cardBackgroundColor="#color/card_background"
android:layout_marginVertical="5dp"
android:layout_marginHorizontal="10dp"
app:cardCornerRadius="8dp">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<ImageView
android:id="#+id/is_app_or_web_image_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="#dimen/card_spacing"
android:padding="#dimen/image_padding"
app:layout_constraintBottom_toBottomOf="#id/delete_image_view"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="#id/delete_image_view"
tools:src="#drawable/is_website_icon_24" />
<TextView
android:id="#+id/service_name_text_view"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginHorizontal="#dimen/card_spacing"
android:text="#string/service_name"
android:textSize="16sp"
app:layout_constraintBottom_toBottomOf="#id/delete_image_view"
app:layout_constraintLeft_toRightOf="#id/is_app_or_web_image_view"
app:layout_constraintRight_toLeftOf="#id/edit_image_view"
app:layout_constraintTop_toTopOf="#id/delete_image_view" />
<androidx.appcompat.widget.AppCompatImageButton
android:id="#+id/delete_image_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="#dimen/card_spacing"
android:layout_marginEnd="#dimen/card_spacing"
android:background="#color/card_foreground"
android:padding="#dimen/image_padding"
android:src="#drawable/ic_baseline_delete_20"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<androidx.appcompat.widget.AppCompatImageButton
android:id="#+id/show_image_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="#dimen/card_spacing"
android:background="#color/card_foreground"
android:padding="#dimen/image_padding"
android:src="#drawable/ic_baseline_show_20"
app:layout_constraintBottom_toBottomOf="#id/delete_image_view"
app:layout_constraintRight_toLeftOf="#id/delete_image_view"
app:layout_constraintTop_toTopOf="#id/delete_image_view" />
<androidx.appcompat.widget.AppCompatImageButton
android:id="#+id/edit_image_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="#dimen/card_spacing"
android:background="#color/card_foreground"
android:padding="#dimen/image_padding"
android:src="#drawable/ic_baseline_edit_20"
app:layout_constraintBottom_toBottomOf="#id/delete_image_view"
app:layout_constraintRight_toLeftOf="#id/show_image_view"
app:layout_constraintTop_toTopOf="#id/delete_image_view" />
<androidx.cardview.widget.CardView
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginVertical="#dimen/card_spacing"
app:cardBackgroundColor="#color/card_foreground"
app:cardCornerRadius="#dimen/corner_radius"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="#id/is_app_or_web_image_view"
app:layout_constraintRight_toRightOf="#id/delete_image_view"
app:layout_constraintTop_toBottomOf="#id/is_app_or_web_image_view">
<com.google.android.material.textview.MaterialTextView
android:id="#+id/service_password_text_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="8dp"
android:background="#00000000"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:text="#string/service_password" />
</androidx.cardview.widget.CardView>
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.cardview.widget.CardView>
what I have already tried -
setting the list item's height to be a fixed value. something like 200 dp (that had no effect. It was as if that value wasn't even entered)
tried changing layout managers(no effect)
now, I don't even know what to try. any help is useful.
adapter code -
package com.kenetic.savepass.adapters
import android.util.Log
import android.view.LayoutInflater
import android.view.ViewGroup
import androidx.recyclerview.widget.DiffUtil
import androidx.recyclerview.widget.ListAdapter
import androidx.recyclerview.widget.RecyclerView
import com.kenetic.savepass.R
import com.kenetic.savepass.databinding.PassListBinding
import com.kenetic.savepass.password.PasswordData
class PassAdapter() :
ListAdapter<PasswordData, PassAdapter.PassViewHolder>(diffCallBack) {
class PassViewHolder(val binding: PassListBinding) : RecyclerView.ViewHolder(binding.root) {
var verifiedWithPassword = false
private val TAG = "PassAdapter"
fun bind(passwordData: PasswordData) {
binding.isAppOrWebImageView.setImageResource(
if (passwordData.isAnApplication) {
R.drawable.is_application_icon_24
} else {
R.drawable.is_website_icon_24
}
)
binding.serviceNameTextView.text = passwordData.serviceName
binding.servicePasswordTextView.text = passwordData.servicePassword
binding.deleteImageView.setOnClickListener {
Log.d(TAG, "delete image onClick working")
}
binding.showImageView.setOnClickListener {
Log.d(TAG, "show image onClick working")
}
binding.editImageView.setOnClickListener {
Log.d(TAG, "edit image onClick working")
}
}
}
companion object {
private val diffCallBack = object : DiffUtil.ItemCallback<PasswordData>() {
override fun areItemsTheSame(oldItem: PasswordData, newItem: PasswordData) =
(oldItem.id == newItem.id)
override fun areContentsTheSame(oldItem: PasswordData, newItem: PasswordData) =
(oldItem == newItem)
}
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): PassViewHolder {
return PassViewHolder(PassListBinding.inflate(LayoutInflater.from(parent.context)))
}
override fun onBindViewHolder(holder: PassViewHolder, position: Int) {
holder.bind(getItem(position))
}
}
I had the same problem, but it turned that I wasn't inflating the recyclerview item the good way.
I was previously inflating these parameters :
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): TodoViewHolder {
return TodoViewHolder(
TodoListItemBinding.inflate(LayoutInflater.from(parent.context))
)
}
And here's the inflating way that made margin between items appear correctly :
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): TodoViewHolder {
return TodoViewHolder(
TodoListItemBinding.inflate(LayoutInflater.from(parent.context), parent, false)
)
}
list item will work remove margin android:layout_marginVertical="5dp" android:layout_marginHorizontal="10dp" and add this line android:layout_margin="5dp" if you want use margin different using margin top and margin_bottom instead of marginvertical
(answering my own question) (work around)
my list item xml was a card layout. I changed it such that the card layout was inside a constraint layout and then constrained the card layout to all four sides of the parent constraint layout. So, now my list item xml is a constraint layout with a card layout inside it. Then, I added margin to the card layout which gave spacing between the border of the card layout and the constraint layout. So, now I visually have spacing between my list items.
the next issue is the constraint layout background being of white colour. To fix that, set the constraint layout colour to be transparent #00000000 . That's all.
Florian-Martin answered the question perfectly. and the solution is very simple
in your
#override
ViewHolder onCreateViewHolder(ViewGroup parent, int viewType){
}
method change following line.
return PassViewHolder(PassListBinding
.inflate(LayoutInflater
.from(parent.getContext())));
to
return PassViewHolder(PassListBinding
.inflate(LayoutInflater
// add ViewGroup parent and boolean attachToRoot parameters
.from(parent.getContext())),parent,false);
my listview has a relative layout parent, it is set to wrap hight and match width, the problem is in the listview height, when i set it to 100dp it works fine, the items show, but when i set it to wrap or match parent it clips and only show one or non of the items, i can see that there is a scroll bar at the side as well, how can i make it wrap?
<RelativeLayout
android:id="#+id/expandable_rl"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="#dimen/xlarge">
<ListView
android:id="#+id/lisview"
android:layout_width="match_parent"
android:layout_height="100dp"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true"
android:layout_alignParentEnd="true"
app:layout_constraintVertical_bias="1.0"
android:layout_alignParentBottom="true"
app:layout_constraintHorizontal_bias="0.0" />
</RelativeLayout>
and this is how i am setting it, its just to test it, its located in a recycler view
holder.list.adapter = ArrayAdapter(holder.itemView.context, R.layout.simple_item, arrayListOf("hello","hi","testing"))
this is how i expand the expandable layout
holder.itemView.setOnClickListener {
if (unitsList[position].isExpandable) {
holder.expandableRL.visibility = if (holder.expandableRL.visibility == View.GONE) View.VISIBLE else View.GONE
}
}
i tried using notifyItemChanged(position) but it made it expand then immediately collapse for some reason
i am new here and don't know how to fix this at the moment
A fully wrapped list means it doesn't scroll, as all of items are visible.
If that is the case, why using a ListView in the first place.
Here is a suggestion to make use of LinearLayout instead.
XML for RecyclerView item:
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content"
>
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
android:text="Click Me" />
<LinearLayout
android:id="#+id/expandable_rl"
android:layout_width="0dp"
android:layout_height="wrap_content"
app:layout_constraintTop_toBottomOf="#id/button"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
android:visibility="gone"
android:orientation="vertical">
</LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
And Here's the adapter:
class RecyclerAdapter: RecyclerView.Adapter<RecyclerView.ViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
return ViewHolder(
LayoutInflater.from(parent.context).inflate(
R.layout.recycler_item,
parent,
false
)
)
}
override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
(holder as? ViewHolder)?.itemView?.let { itemView ->
val expandable = itemView.findViewById<LinearLayout>(R.id.expandable_rl)
createItems(expandable)
itemView.findViewById<Button>(R.id.button).setOnClickListener {
expandable.visibility = View.VISIBLE
}
}
}
private fun createItems(expandable: LinearLayout) {
listOf("Hi", "Hello", "Goodbye").forEach { word ->
val item = createItem(expandable.context, word)
expandable.addView(item)
}
}
private fun createItem(context: Context, word: String): View {
return LinearLayout(context).apply {
layoutParams = LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT)
orientation = LinearLayout.VERTICAL
gravity = Gravity.CENTER
addView(
TextView(context).apply {
layoutParams = LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT)
text = word
}
)
}
}
override fun getItemCount(): Int {
return 30
}
class ViewHolder(view: View): RecyclerView.ViewHolder(view)
}
This is a basic design, but you can take it from here and design what you need.
I'm a Kotlin newbie learning how to create simple recyclerview apps. My code is supposed to list the integers 1..10 in vertically stacked cells. However, it only lists the first item. I've consulted several tutorials and reviewed my code several times(after long breaks), but I can't see anything wrong in my code.
I got the bright idea early today to print Log statements. Examining them, I note that my onBindViewHolder function is only called once. What blunder am I making?
Here is my log output:
D/QuoteAdapter: value is: 1
D/QuoteAdapter: index is: 0
D/QuoteAdapter: Size is: 10
my activity:
class MainActivity : AppCompatActivity() {
lateinit var mRecyclerView: RecyclerView
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
mRecyclerView = findViewById(R.id.recyclerView)
mRecyclerView.layoutManager = LinearLayoutManager(this)
mRecyclerView.adapter = QuoteAdapter()
//mRecyclerView.setHasFixedSize(true)
}
}
my adapter:
class QuoteAdapter : RecyclerView.Adapter<QuoteViewHolder>() {
private val listOfInts = intArrayOf(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
private val TAG = "QuoteAdapter"
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): QuoteViewHolder {
val view = LayoutInflater.from(parent.context)
.inflate(R.layout.recyclerview_item_row, parent, false)
return QuoteViewHolder(view)
}
override fun getItemCount(): Int {
Log.d(TAG, "Size is: ${listOfInts.size.toString()}")
return listOfInts.size
}
override fun onBindViewHolder(holder: QuoteViewHolder, position: Int) {
val item = listOfInts[position]
Log.d(TAG, "value is: ${item.toString()}")
Log.d(TAG, "index is: ${position.toString()}")
holder.listTitle.text = item.toString()
}
}
my viewholder:
class QuoteViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
val listTitle = itemView.findViewById(R.id.itemString) as TextView
}
my layout:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/itemString"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
my main layout is shown below:
<androidx.constraintlayout.widget.ConstraintLayout 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="match_parent"
tools:context=".MainActivity">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginStart="8dp"
android:layout_marginLeft="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:layout_marginRight="8dp"
android:layout_marginBottom="8dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
In your "my layout" try this:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:id="#+id/itemString"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
Notice layout_height of LinearLayout has changed to wrap_content
Also doubt you need the android:orientation="vertical" on your ViewHolders item xml unless you will add more than just 1 TextView in the future.
Like Zain says, you can just use a TextView on its own in a layout file, which will also fix the problem (so long as its height is wrap_content!)
There are actually a few included with Android - type android.R.layout. and you'll see a few things, like simple_list_item_1 which is just a styled TextView (you can ctrl+click the reference or whatever to look at the file). Can be nice if you just want to make a quick thing!
The ID of the TextView in android.R.layout.simple_list_item_1 is #android:id/text1 - note the android prefix, because its part of the android resources, not your app's. Which means you have to reference the ID in the same way as the layout, with android at the front: android.R.id.text1
You can get rid of the LinearLayout in the list item layout, and only keep the TextView.
So, replace your list item layout with:
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/itemString"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
I have a Fragment that displays a list of cities with weather informations. I am using a RecyclerView and I am trying to implement the Data Binding Library in my RecyclerView Adapter but for some reason I get this compile error :
> error: cannot find symbol import
com.example.zach.weatherapp.databinding.CityListItemBindingImpl;
> ^
> symbol: class CityListItemBindingImpl
> location: package com.example.zach.weatherapp.databinding
It's an auto generated class so i really don't know where the error is. I had the same error previously for other layouts when there was someting wrong in the xml file but here it seems fine.
ForecastAdapter.kt
package com.example.zach.weatherapp.Adapter
import ...
class ForecastAdapter(var myDataset: List<City>) :
RecyclerView.Adapter<ForecastAdapter.ForecastViewHolder>() {
var context:Context?=null
// Provide a reference to the views for each data item
// Complex data items may need more than one view per item, and
// you provide access to all the views for a data item in a view holder.
class ForecastViewHolder(var binding: CityListItemBinding) : RecyclerView.ViewHolder(binding.root){
fun bind(city: City){
binding.city = city
}
}
// Create new views (invoked by the layout manager)
override fun onCreateViewHolder(parent: ViewGroup,
viewType: Int): ForecastAdapter.ForecastViewHolder {
context = parent.context
val layoutIdForListItem = R.layout.city_list_item
val inflater = LayoutInflater.from(context)
val shouldAttachToParentImmediately = false
val binding = DataBindingUtil.inflate<CityListItemBinding>(inflater,layoutIdForListItem,parent,shouldAttachToParentImmediately)
//val view = inflater.inflate(layoutIdForListItem, parent, shouldAttachToParentImmediately)
return ForecastViewHolder(binding)
}
// Replace the contents of a view (invoked by the layout manager)
override fun onBindViewHolder(holder: ForecastViewHolder, position: Int) {
val city = myDataset[position]
holder.bind(city)
Glide.with(context)
.load("http://openweathermap.org/img/w/${city.weather[0].icon}.png")
.into(holder.binding.forceastImageView)
holder.binding.container.setOnClickListener{ view: View ->
Timber.d("Clicked on city %s",city.name)
Navigation.findNavController(view).navigate(ListFragmentDirections.actionListFragmentToForecastDetailsFragment(city.id))}
}
// Return the size of your dataset (invoked by the layout manager)
override fun getItemCount() = myDataset.size
}
city_list_item.xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
xmlns:android="http://schemas.android.com/apk/res/android">
<data>
<variable name="city" type="com.example.zach.weatherapp.data.City"/>
</data>
<androidx.constraintlayout.widget.ConstraintLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/container">
<TextView
tools:text="Caen"
android:text="#{city.name}"
android:layout_width="wrap_content"
android:layout_height="wrap_content" android:id="#+id/city_name_textview"
app:layout_constraintStart_toStartOf="parent" android:layout_marginStart="16dp"
android:layout_marginTop="16dp" app:layout_constraintTop_toTopOf="parent"
android:fontFamily="#font/roboto_light" android:textSize="22sp" android:textStyle="bold"
android:maxLines="1" android:ellipsize="end"/>
<TextView
tools:text="Sunny"
android:text="#{city.weather[0].description}"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/city_forecast_textview" app:layout_constraintStart_toStartOf="parent"
android:layout_marginStart="16dp"
app:layout_constraintTop_toBottomOf="#+id/city_name_textview" android:fontFamily="#font/roboto_light"
android:layout_marginBottom="16dp" app:layout_constraintBottom_toBottomOf="parent"/>
<ImageView
android:layout_width="48dp"
android:layout_height="48dp" app:srcCompat="#drawable/sunny"
android:id="#+id/forceast_imageView" android:layout_marginTop="8dp"
app:layout_constraintTop_toTopOf="parent" android:layout_marginBottom="8dp"
app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintVertical_bias="0.562"
android:layout_marginEnd="32dp" app:layout_constraintEnd_toStartOf="#+id/temperatures_layout"/>
<LinearLayout
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content" android:id="#+id/temperatures_layout"
app:layout_constraintEnd_toEndOf="parent" android:layout_marginEnd="16dp" android:layout_marginBottom="8dp"
app:layout_constraintBottom_toBottomOf="parent" android:layout_marginTop="8dp"
app:layout_constraintTop_toTopOf="parent">
<TextView
tools:text="15°"
android:text="#{city.main.temp_max}"
android:layout_width="wrap_content"
android:layout_height="wrap_content" android:id="#+id/max_temperature_textview"
android:fontFamily="#font/roboto_light"
tools:layout_editor_absoluteY="17dp" tools:layout_editor_absoluteX="313dp"/>
<TextView
tools:text="9°"
android:text="#{city.main.temp_min}"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/min_temperature_textview"
android:fontFamily="#font/roboto_light" tools:layout_editor_absoluteY="45dp"
tools:layout_editor_absoluteX="321dp" android:layout_gravity="right"/>
</LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
</layout>
It might just be an Android Studio error because the xml file seems fine.
UPDATE :
Error seems to come from Xml. I removed the android:text="#{city.xxx}" in my xml layout and instead updated my textViews manually in my ViewHolder bind method like so :
fun bind(boundCity: City){
with(binding){
cityNameTextview.text = boundCity.name
cityForecastTextview.text = boundCity.weather[0].description
maxTemperatureTextview.text = "${boundCity.main.temp_max}°"
minTemperatureTextview.text = "${boundCity.main.temp_min}°"
Glide.with(root.context)
.load("http://openweathermap.org/img/w/${boundCity.weather[0].icon}.png")
.into(forceastImageView)
container.setOnClickListener{ view: View ->
Timber.d("Clicked on city %s",boundCity.name)
Navigation.findNavController(view).navigate(ListFragmentDirections.actionListFragmentToForecastDetailsFragment(boundCity.id))}
}
}
And I no longer get the error. The error comes whenever I add android:text="#{city.xx}" in my textviews and bind the city variable in the bind method. I still don't know why though....
This should work for you I believe;
class ForecastAdapter(private var myDataset: List<City>) : RecyclerView.Adapter<ForecastAdapter.ForecastViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ForecastAdapter.ForecastViewHolder {
val itemBinding = CityListItemBinding.inflate(LayoutInflater.from(parent.context), parent, false)
return ForecastViewHolder(itemBinding)
}
override fun onBindViewHolder(holder: ForecastViewHolder, position: Int) {
val city = myDataset[position]
holder.bind(city)
}
override fun getItemCount() = myDataset.size
inner class ForecastViewHolder(var binding: CityListItemBinding) : RecyclerView.ViewHolder(binding.root){
fun bind(boundCity: City){
with(binding) {
city = boundCity
Glide.with(root.context)
.load("http://openweathermap.org/img/w/${city.weather[0].icon}.png")
.into(forceastImageView)
container.setOnClickListener { view ->
Timber.d("Clicked on city %s", city.name)
Navigation.findNavController(view).navigate(ListFragmentDirections.actionListFragmentToForecastDetailsFragment(city.id))
}
}
}
Hey you could try adding the following line after the <data> tag :
<import type="android.view.View" />
I found that worked for me when I had that error.