When I try to run the app my recycler view unable to generate the output.
It is unable to load data and there is no error the code.
Below is adapter class
PlayerListAdapter.java
public class PlayerListAdapter extends RecyclerView.Adapter<PlayerListAdapter.FeaturedViewHolder> {
ArrayList<plaerListHelperClass> featuredLocation;
public PlayerListAdapter(ArrayList<plaerListHelperClass> featuredLocation) {
this.featuredLocation = featuredLocation;
}
#NonNull
#Override
public FeaturedViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.playerlist,parent,false);
FeaturedViewHolder featuredViewHolder= new FeaturedViewHolder(view);
return featuredViewHolder;
}
#Override
public void onBindViewHolder(#NonNull FeaturedViewHolder holder, int position) {
plaerListHelperClass plaerListHelperClass = featuredLocation.get(position);
String namep= plaerListHelperClass.getPlayerName();
String mailp= plaerListHelperClass.getPlayerEmail();
holder.name.setText(namep);
holder.mail.setText(mailp);
}
#Override
public int getItemCount() {
return featuredLocation.size();
}
public static class FeaturedViewHolder extends RecyclerView.ViewHolder{
TextView name,mail;
public FeaturedViewHolder(#NonNull View itemView) {
super(itemView);
name=itemView.findViewById(R.id.playerName);
mail=itemView.findViewById(R.id.pmail);
}
}
mainactivity.java
This is main activity of my code
public class MainActivity extends AppCompatActivity {
RecyclerView featuredRecycler;
RecyclerView.Adapter adapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
featuredRecycler=findViewById(R.id.playerListRecyclerView);
featuredRecycler();
}
private void featuredRecycler() {
featuredRecycler.setHasFixedSize(true);
ArrayList<plaerListHelperClass> featuredLocation = new ArrayList<>();
featuredLocation.add(new plaerListHelperClass("Shubham","Shubham#gmail.com"));
featuredLocation.add(new plaerListHelperClass("Shubham","Shubham#gmail.com"));
featuredLocation.add(new plaerListHelperClass("Shubham","Shubham#gmail.com"));
featuredLocation.add(new plaerListHelperClass("Shubham","Shubham#gmail.com"));
adapter=new PlayerListAdapter(featuredLocation);
featuredRecycler.setAdapter(adapter);
}
Build this helper class to contains the element that is to be send to the recycler view layout
plaerListHelperClass.java
public class plaerListHelperClass {
String playerName;
String playerEmail;
public plaerListHelperClass(String playerName, String playerEmail) {
this.playerName = playerName;
this.playerEmail = playerEmail;
}
public String getPlayerName() {
return playerName;
}
public String getPlayerEmail() {
return playerEmail;
}
}
playerlist.xml
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/white">
<TextView
android:id="#+id/playerName"
android:layout_height="wrap_content"
android:textColor="#897668"
android:layout_weight="1.50"
android:layout_width="match_parent"
android:layout_marginTop="10dp"
android:layout_marginLeft="0dp"/>
<TextView
android:id="#+id/pmail"
android:layout_height="wrap_content"
android:textColor="#897668"
android:layout_below="#+id/name"
android:layout_width="match_parent"
android:layout_weight="1"
android:layout_marginTop="10dp"
android:layout_centerHorizontal="true"/>
</LinearLayout>
activity_main.xml
<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"
android:background="#color/white">
<androidx.recyclerview.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/playerListRecyclerView"
tools:ignore="MissingConstraints" />
</androidx.constraintlayout.widget.ConstraintLayout>
Welcome to the Stack Overflow,
your implementation is correct but I guess you forgot to add the Layout Manager for RecyclerView.
so you can do this by adding it in xml or in your java class as :
activity_main.xml
<?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="match_parent"
tools:context=".MainActivity"
android:background="#color/white">
<!-- for Linear layout...-->
<androidx.recyclerview.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/playerListRecyclerView"
tools:listitem="#layout/playerlist"
tools:itemCount="7"
app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
tools:ignore="MissingConstraints" />
</androidx.constraintlayout.widget.ConstraintLayout>
Or,
you can add it in your java class as
private void featuredRecycler() {
featuredRecycler.setHasFixedSize(true);
ArrayList<plaerListHelperClass> featuredLocation = new ArrayList<>();
featuredLocation.add(new plaerListHelperClass("Shubham","Shubham#gmail.com"));
featuredLocation.add(new plaerListHelperClass("Shubham","Shubham#gmail.com"));
featuredLocation.add(new plaerListHelperClass("Shubham","Shubham#gmail.com"));
featuredLocation.add(new plaerListHelperClass("Shubham","Shubham#gmail.com"));
adapter=new PlayerListAdapter(featuredLocation);
featuredRecycler.setAdapter(adapter);
featuredRecycler.setLayoutManager(new LinearLayoutManager(this#MainActivity))
}
for more reference you can refer https://www.javatpoint.com/android-recyclerview-list-example
Related
Hello guys I want to display one single item between two grid row items.
I want this type of out.
I'm try this way but it didn't work.
My Activity layout XML activity_grid_with_single_rv.xml
<LinearLayout 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=".Activitry.GridWithSingleRVActivity">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/rvGridWithSingle"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="5dp"/>
</LinearLayout>
My Activity class GridWithSingleRVActivity.java
public class GridWithSingleRVActivity extends AppCompatActivity {
private RecyclerView rvGridWithSingle;
private GridWIthSingleRVAdapter gridWIthSingleRVAdapter;
private ArrayList<GridWithSingle> gridWithSingles=new ArrayList<>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_grid_with_single_rv);
rvGridWithSingle=findViewById(R.id.rvGridWithSingle);
getGridWithSingles();
rvGridWithSingle.setLayoutManager(new GridLayoutManager(this,2));
gridWIthSingleRVAdapter=new GridWIthSingleRVAdapter(this,gridWithSingles);
rvGridWithSingle.setAdapter(gridWIthSingleRVAdapter);
}
private ArrayList<GridWithSingle> getGridWithSingles(){
gridWithSingles.clear();
gridWithSingles=new ArrayList<>();
int addSingleCnt=0;
for (int i=0;i<20;i++){
gridWithSingles.add(new GridWithSingle(i+1,"GRID : "+(i+1)));
if (addSingleCnt==1){
addSingleCnt=0;
gridWithSingles.add(new GridWithSingle(-1,"Single : "));
}else {
addSingleCnt++;
}
}
return gridWithSingles;
}
}
My Adapter class GridWIthSingleRVAdapter.java
public class GridWIthSingleRVAdapter extends RecyclerView.Adapter<GridWIthSingleRVAdapter.GridWIthSingleRVVH> {
private Context context;
private ArrayList<GridWithSingle> gridWithSingles=new ArrayList<>();
private final int GRID_LAYOUT=1;
private final int SINGLE_LAYOUT=0;
public GridWIthSingleRVAdapter(Context context, ArrayList<GridWithSingle> gridWithSingles) {
this.context = context;
this.gridWithSingles = gridWithSingles;
}
#NonNull
#Override
public GridWIthSingleRVVH onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
if (viewType==GRID_LAYOUT)
return new GridWIthSingleRVVH(LayoutInflater.from(parent.getContext()).inflate(R.layout.row_grid_item,parent,false));
else
return new GridWIthSingleRVVH(LayoutInflater.from(parent.getContext()).inflate(R.layout.row_single_item,parent,false));
}
#Override
public void onBindViewHolder(#NonNull GridWIthSingleRVVH holder, int position) {
if (holder.getItemViewType()==GRID_LAYOUT){
holder.txtGrid.setText(gridWithSingles.get(position).getName());
}else {
holder.txtSingle.setText(gridWithSingles.get(position).getName());
}
}
#Override
public int getItemCount() {
return gridWithSingles.size();
}
#Override
public int getItemViewType(int position) {
if (gridWithSingles.get(position).getId()==-1){
return SINGLE_LAYOUT;
}else {
return GRID_LAYOUT;
}
}
public class GridWIthSingleRVVH extends RecyclerView.ViewHolder{
private TextView txtGrid,txtSingle;
public GridWIthSingleRVVH(#NonNull View itemView) {
super(itemView);
txtGrid=itemView.findViewById(R.id.txtGrid);
txtSingle=itemView.findViewById(R.id.txtSingle);
}
}
}
Two layout item xml
grid_item.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<androidx.cardview.widget.CardView
android:layout_width="match_parent"
android:layout_height="100dp"
android:id="#+id/cvGrid"
android:layout_margin="10dp"
app:cardCornerRadius="5dp"
app:cardElevation="5dp"
app:cardBackgroundColor="#EF9A9A">
<TextView
android:id="#+id/txtGrid"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="GRID"
android:layout_gravity="center"
android:textStyle="bold"
android:textSize="18sp"
android:textColor="#color/black"/>
</androidx.cardview.widget.CardView>
</LinearLayout>
single_item.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<androidx.cardview.widget.CardView
android:layout_width="match_parent"
android:layout_height="100dp"
android:id="#+id/cvSingle"
android:layout_margin="10dp"
app:cardCornerRadius="5dp"
app:cardElevation="5dp"
app:cardBackgroundColor="#CE93D8">
<TextView
android:id="#+id/txtSingle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="SINGLE"
android:layout_gravity="center"
android:textStyle="bold"
android:textSize="18sp"
android:textColor="#color/black"/>
</androidx.cardview.widget.CardView>
</LinearLayout>
Output
You need to specify a spanSizeLookup for the affected columns to the layoutManager.
A couple of years ago I wrote a similar proof of concepts where the idea was to insert "ads" every 4 rows.
The project is located on GitHub.
The sample does this the trick directly in the activity by using recyclerView types and modifying the span size.
layoutManager = GridLayoutManager(this, 2)
mainRecyclerView.layoutManager = layoutManager
mainRecyclerView.adapter = adapter
layoutManager.spanSizeLookup = object : GridLayoutManager.SpanSizeLookup() {
override fun getSpanSize(position: Int): Int {
return when (adapter.getItemViewType(position)) {
adapter.viewTypeGreen -> 1
adapter.viewTypePurple -> 1
adapter.viewTypeAd -> 2
else -> -1
}
}
}
The repository that provides this data simulates inserting a different type every 4 items
I have an AlertDialog in it there used to be a ListView in which the contents of the ArrayList were displayed. For beauty, I decided to replace it with Recyclerview, Card and the problems started.
Items are added to ArrayList <String> mainListWord during the work and they should be included in the Recyclerview cards. The problem is that either the entire list falls into one card at once, or each next card contains the previous elements + 1. For example: the first card: 1 element, the second card: 2 elements, etc.
How to implement it so that when a new element is added to the array, it will be placed in its own card?
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
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"
tools:context=".MainActivity">
<EditText
android:id="#+id/innerText"
android:layout_width="wrap_content"
android:layout_height="50dp"
android:layout_centerInParent="true"/>
<Button
android:id="#+id/press"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="Press"
android:layout_below="#id/innerText"
android:layout_centerHorizontal="true"
android:onClick="openDialog"/>
</RelativeLayout>
recycler_item.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
xmlns:app="http://schemas.android.com/apk/res-auto"
app:cardCornerRadius="4dp"
android:layout_margin="4dp"
app:cardBackgroundColor="#color/colorCardBack">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="5dp"
android:background="#color/colorCard">
<ImageView
android:id="#+id/imageView_1"
android:layout_width="50dp"
android:layout_height="50dp"
android:padding="4dp" />
<TextView
android:id="#+id/textview_1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Text_1"
android:textStyle="bold"
android:textColor="#android:color/black"
android:layout_centerInParent="true"
android:textSize="16sp"
android:layout_marginStart="5dp"
android:layout_toEndOf="#id/imageView_1"/>
</RelativeLayout>
</androidx.cardview.widget.CardView>
stats_fragment.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
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"
tools:context=".MainActivity">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="50dp"
android:layout_margin="10dp"
android:background="#color/colorAccent"
android:scrollbars="vertical"
android:layout_above="#id/butClose"/>
<Button
android:id="#+id/butClose"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="5dp"
android:layout_centerHorizontal="true"
android:layout_alignParentBottom="true"/>
</RelativeLayout>
MainActivity.java
public class MainActivity extends AppCompatActivity {
private EditText innerText;
private Button press, butClose;
private ArrayList<RecyclerViewItem> recyclerViewItem;
private ArrayList<String> mainListWord;
private AlertDialog OptionDialog;
private RecyclerView recyclerView;
private RecyclerView.Adapter adapter;
private RecyclerView.LayoutManager layoutManager;
#RequiresApi(api = Build.VERSION_CODES.O)
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
recyclerViewItem = new ArrayList<>();
mainListWord = new ArrayList<>();
innerText = findViewById(R.id.innerText);
press = findViewById(R.id.butClose);
}
#RequiresApi(api = Build.VERSION_CODES.O)
public void makeRecyclerList(ArrayList<String> income){
String[] listWord_lenght = income.toArray(new String[0]);
String keyWord = (String.join("", listWord_lenght));
recyclerViewItem.add(new RecyclerViewItem(R.drawable.star, keyWord));
}
#RequiresApi(api = Build.VERSION_CODES.O)
public void openDialog(View v){
String word = innerText.getText().toString();
mainListWord.add(word);
makeRecyclerList(mainListWord);
Dialogus();
innerText.setText("");
}
public void Dialogus(){
LayoutInflater li = (LayoutInflater) this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v = li.inflate(R.layout.stats_fragment, null, false);
OptionDialog = new AlertDialog.Builder(this).create();
OptionDialog.setTitle("TestInfo");
recyclerView = v.findViewById(R.id.recycler_view);
recyclerView.setHasFixedSize(true);
adapter = new RecyclerViewAdapter(recyclerViewItem);
layoutManager = new LinearLayoutManager(this);
recyclerView.setAdapter(adapter);
recyclerView.setLayoutManager(layoutManager);
butClose = v.findViewById(R.id.butClose);
OptionDialog.setView(v);
OptionDialog.setCancelable(true);
butClose.setBackgroundColor(Color.CYAN);
butClose.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
OptionDialog.dismiss();
}
});
OptionDialog.show();
}
}
RecyclerViewAdapter.java
public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.RecyclerViewViewHolder> {
private ArrayList<RecyclerViewItem> arrayList;
public static class RecyclerViewViewHolder extends RecyclerView.ViewHolder {
public ImageView imageView_1;
public TextView textview_1;
public RecyclerViewViewHolder(#NonNull View itemView) {
super(itemView);
imageView_1 = itemView.findViewById(R.id.imageView_1);
textview_1 = itemView.findViewById(R.id.textview_1);
}
}
public RecyclerViewAdapter(ArrayList<RecyclerViewItem> arrayList){
this.arrayList = arrayList;
}
#NonNull
#Override
public RecyclerViewViewHolder onCreateViewHolder(#NonNull ViewGroup viewGroup, int viewType) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.recycler_item, viewGroup, false);
RecyclerViewViewHolder recyclerViewViewHolder= new RecyclerViewViewHolder(view);
return recyclerViewViewHolder;
}
#Override
public void onBindViewHolder(#NonNull RecyclerViewViewHolder recyclerViewViewHolder, int position) {
RecyclerViewItem recyclerViewItem = arrayList.get(position);
recyclerViewViewHolder.imageView_1.setImageResource(recyclerViewItem.getImageResource());
recyclerViewViewHolder.textview_1.setText(recyclerViewItem.getText_1());
}
#Override
public int getItemCount() {
return arrayList.size();
}
}
RecyclerViewItem.java
package freijer.app.one;
public class RecyclerViewItem {
private int imageResource;
private String text_1;
public int getImageResource() {
return imageResource;
}
public void setImageResource(int imageResource) {
this.imageResource = imageResource;
}
public String getText_1() {
return text_1;
}
public void setText_1(String text_1) {
this.text_1 = text_1;
}
public RecyclerViewItem(int imageResource, String text_1) {
this.imageResource = imageResource;
this.text_1 = text_1;
}
}
I'm new to Android Studio and coding in general and I am trying to display a custom ListView with an image of a colour and the name of the colour. I have used a custom Adapter to inflate the view with two arrays containing the drawable image colours and string of the names.
The problem I am having - the custom adapter is only displaying the layers from position 1 and onwards. For example, where the first layer should be img_01 and "red" - it is displaying img_02 and "Orange".
I've tried debugging the code and it seems that though the adapter is setting the values for position 0, but I cannot find the reason why it is not displaying (as the others are displaying fine).
The images & names are just placeholders, so an alternative solution that doesn't include both the drawables and names wouldn't be viable,
Thank you in advance
CustomAdapter.java
public class CustomAdapter extends BaseAdapter {
Context context;
int[] images;
String[] colour;
LayoutInflater mInflater;
public CustomAdapter(Context c, int[] i, String[] col) {
this.context = c; //sets the application context that has been passed to the adapter
this.images = i; //sets the images array that has been passed to the adapter
this.colour = col; //sets the colour array that has been passed to the adapter
mInflater = (LayoutInflater.from(context)); //sets the layout inflater from context
}
#Override
public int getCount() { //total number of elements in the array
return images.length;
}
#Override
public Object getItem(int position) { //gets the item using the position
return null;
}
#Override
public long getItemId(int position) { //gets the item position
return position;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) { //this is used to update the view
convertView = mInflater.inflate(R.layout.custom_layout, null);
ImageView image = convertView.findViewById(R.id.imageView);
TextView text = convertView.findViewById(R.id.textView);
text.setText(colour[position]);
image.setImageResource(images[position]);
return convertView;
}
}
MainActivity.java
public class MainActivity extends AppCompatActivity {
ListView mListView;
int[] images = {R.drawable.img01,
R.drawable.img02,
R.drawable.img03,
R.drawable.img04};
String[] colour = {"Red",
"Orange",
"Yellow",
"Green"};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mListView = findViewById(R.id.listView);
CustomAdapter customAdapter = new CustomAdapter(getApplicationContext(), images, colour);
//passes information of images and application context to the item adapter
mListView.setAdapter(customAdapter);
//sets the adapter to the listview
}
}
custom_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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="match_parent">
<ImageView
android:id="#+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginStart="7dp"
android:layout_marginLeft="7dp"
android:layout_marginTop="9dp"
app:srcCompat="#drawable/img01" />
<TextView
android:id="#+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginStart="99dp"
android:layout_marginLeft="99dp"
android:layout_marginTop="36dp"
android:text="colourName" />
</RelativeLayout>
activity_main.xml
<?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="match_parent"
tools:context=".MainActivity">
<ListView
android:id="#+id/listView"
android:layout_width="409dp"
android:layout_height="729dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
Try to set the height of the ListView to wrap_content instead of hardcoding it
<ListView
...
android:layout_height="wrap_content"/>
You can do it with RecyclerView.
Create a custom class
public class ExampleItem {
private int mImageResource; //your color image
private String mText1; //your text
public ExampleItem(int imageResource, String text1) {
mImageResource = imageResource;
mText1 = text1;
}
public int getImageResource() {
return mImageResource;
}
public String getText1() {
return mText1;
}
}
Create a XML 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"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="4dp"
app:cardCornerRadius="4dp">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="4dp">
<ImageView
android:id="#+id/imageView"
android:layout_width="50dp"
android:layout_height="50dp"
android:padding="2dp" />
<TextView
android:id="#+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_toEndOf="#+id/imageView"
android:text="Line 1"
android:textColor="#android:color/black"
android:textSize="20sp"
android:textStyle="bold" />
</RelativeLayout>
</android.support.v7.widget.CardView>
Create a Recycler View Adapter
public class ExampleAdapter extends RecyclerView.Adapter<ExampleAdapter.ExampleViewHolder> {
private ArrayList<ExampleItem> mExampleList;
public static class ExampleViewHolder extends RecyclerView.ViewHolder {
public ImageView mImageView;
public TextView mTextView1;
public ExampleViewHolder(View itemView) {
super(itemView);
mImageView = itemView.findViewById(R.id.imageView);
mTextView1 = itemView.findViewById(R.id.textView);
}
}
public ExampleAdapter(ArrayList<ExampleItem> exampleList) {
mExampleList = exampleList;
}
#Override
public ExampleViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.example_item, parent, false);
ExampleViewHolder evh = new ExampleViewHolder(v);
return evh;
}
#Override
public void onBindViewHolder(ExampleViewHolder holder, int position) {
ExampleItem currentItem = mExampleList.get(position);
holder.mImageView.setImageResource(currentItem.getImageResource());
holder.mTextView1.setText(currentItem.getText1());
}
#Override
public int getItemCount() {
return mExampleList.size();
}
}
your activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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="com.example.application.recyclerviewproject.MainActivity">
<android.support.v7.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:color/darker_gray"
android:padding="4dp"
android:scrollbars="vertical" />
</RelativeLayout>
MainActivity.java
public class MainActivity extends AppCompatActivity {
private RecyclerView mRecyclerView;
private RecyclerView.Adapter mAdapter;
private RecyclerView.LayoutManager mLayoutManager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ArrayList<ExampleItem> exampleList = new ArrayList<>();
exampleList.add(new ExampleItem(R.drawable.img01, "Red"));
exampleList.add(new ExampleItem(R.drawable.img02, "Orange"));
exampleList.add(new ExampleItem(R.drawable.img03, "Yellow"));
exampleList.add(new ExampleItem(R.drawable.img04, "Green"));
mRecyclerView = findViewById(R.id.recyclerView);
mRecyclerView.setHasFixedSize(true);
mLayoutManager = new LinearLayoutManager(this);
mAdapter = new ExampleAdapter(exampleList);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(mAdapter);
}
}
I'm trying to start another activity after clicking on a CardView inside a RecyclerView. The new activity renders after the click on any of the items inside the RecyclerView (It does the transition and changes the title TextView), but it does not show any of the TextView's inside the CardView on the layout.
The OnClick method is being set as an interface and being implemented in the first Activity.
Here is my first activity. I'm loading the data here from a SQLite database, but it's not relevant for the question to show the code from it.
public class MainActivity extends AppCompatActivity implements RecipeAdapterMain.OnCardListener {
private TextView tv;
ArrayList<RecipeObject> recipes = new ArrayList<>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
RecyclerView rv = findViewById(R.id.recipeListMain);
LinearLayoutManager llm = new LinearLayoutManager(this);
rv.setLayoutManager(llm);
RecipeAdapterMain adapter = new RecipeAdapterMain(recipes, this);
rv.setAdapter(adapter);
tv = findViewById(R.id.title);
}
#Override
public void onCardClick(int position) {
Intent intent = new Intent(this, RecipeActivity.class);
startActivity(intent);
}
}
This is my Adapter.
public class RecipeAdapterMain extends RecyclerView.Adapter<RecipeAdapterMain.RecipeListViewHolder> {
RecyclerView mRecyclerView;
ArrayList<RecipeObject> recipeList;
private OnCardListener mOnCardListener;
public RecipeAdapterMain(Context context, ArrayList<RecipeObject> recipeList, OnCardListener onCardListener) {
this.mOnCardListener = onCardListener;
this.recipeList = recipeList;
}
#Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
mRecyclerView = recyclerView;
super.onAttachedToRecyclerView(recyclerView);
}
#Override
public RecipeListViewHolder onCreateViewHolder(ViewGroup parent, int i) {
View layoutView = LayoutInflater.from(parent.getContext()).inflate(R.layout.layout_recipe_main, parent, false);
RecipeListViewHolder rcv = new RecipeListViewHolder(layoutView, mOnCardListener);
return rcv;
}
#Override
public void onBindViewHolder(#NonNull RecipeListViewHolder holder, int position) {
holder.mName.setText(recipeList.get(position).getName());
}
#Override
public int getItemCount(){
return recipeList.size();
}
public class RecipeListViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{
public TextView mName;
OnCardListener onCardListener;
public RecipeListViewHolder(final View view, OnCardListener onCardListener) {
super(view);
mName = view.findViewById(R.id.textViewTitle);
this.onCardListener = onCardListener;
view.setOnClickListener(this);
}
#Override
public void onClick(View v) {
onCardListener.onCardClick(getAdapterPosition());
}
}
public interface OnCardListener {
void onCardClick(int position);
}
}
My second activity:
public class RecipeActivity extends AppCompatActivity {
#Override
public void onCreate(#Nullable Bundle savedInstanceState, #Nullable PersistableBundle persistentState) {
super.onCreate(savedInstanceState, persistentState);
setContentView(R.layout.layout_recipe);
}
}
This is the layout from the second activity. (layout_recipe):
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="wrap_content">
<androidx.cardview.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="#+id/textViewName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="This is a test"
android:textColor="#1A1A1A"
android:textSize="18sp" />
<TextView
android:id="#+id/textViewIngr"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="This is a test"
android:textColor="#1A1A1A"
android:textSize="18sp" />
<TextView
android:id="#+id/textViewDire"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="This is a test"
android:textColor="#1A1A1A"
android:textSize="18sp" />
</LinearLayout>
</androidx.cardview.widget.CardView>
</LinearLayout>
And this is the layout from the first activity (activity_main):
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout 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">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/AppTheme.AppBarOverlay">
</com.google.android.material.appbar.AppBarLayout>
<androidx.recyclerview.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/recipeListMain"
android:scrollbars="vertical">
</androidx.recyclerview.widget.RecyclerView>
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:backgroundTint="#color/colorAccent"
android:layout_gravity="end|bottom"
android:layout_margin="16dp"
android:layout_marginBottom="16dp"
android:contentDescription="#string/submit"
android:src="#drawable/ic_add_black_24dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
android:onClick="openActivityCreate"/>
</androidx.coordinatorlayout.widget.CoordinatorLayout>
From clicking in a Card on the MainActivity, I expected to render the second activity with it's TextViews (This is a test), but it's rendering a blank page instead.
try removing #Nullable PersistableBundle persistentState from onCreate on your second activity
I have made a custom gridView and a item witch I want to implement in the gridView, but how can I set these custom gridView onCreate inside my HomeActivity class file?
HomeActivity.java
public class HomeActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
// how can I say here that I want to set the gridView from list_holder.xml
}
}
list_holder.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<GridView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/view_item_block_holder"
android:layout_alignParentEnd="false"
android:numColumns="auto_fit"
tools:listitem="#layout/item_block" />
</RelativeLayout>
item_block.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/item_block"
android:padding="5dp">
<LinearLayout
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="10dp"
android:background="#color/secondaryBackgroundColor">
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/secondaryBackgroundColor"
android:paddingLeft="10dp"
android:paddingTop="10dp"
android:paddingRight="10dp">
<ImageView
android:layout_width="150dp"
android:layout_height="150dp"
android:id="#+id/imageView2"
android:background="#drawable/no_image_available" />
</LinearLayout>
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/secondaryBackgroundColor"
android:padding="10dp"
android:layout_margin="5dp">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="video title"
android:id="#+id/item_block_title"
android:textColor="#color/textTitleColor"
android:textStyle="bold"
android:textSize="15dp" />
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="5dp">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="New Text"
android:id="#+id/item_block_description"
android:textColor="#color/textContentColor"
android:textSize="10dp"
android:layout_weight="1" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="12-09-16"
android:id="#+id/item_date"
android:textColor="#color/textContentColor"
android:textSize="10dp"
android:layout_weight="2" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
</RelativeLayout>
HomeActivity.java
public class HomeActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
//Here Adapter like
AdapterDemoGrid adapterDemoGrid = new AdapterDemoGrid(this);
gridView.setAdapter(adapterDemoGrid);
}
}
Here, Adapter for Custom GridView Make this class :
public class AdapterDemoGrid extends BaseAdapter {
private final Context context;
private LayoutInflater mLayoutInflater;
public AdapterDemoGrid(Context context) {
mLayoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
this.context = context;
}
#Override
public void notifyDataSetChanged() {
super.notifyDataSetChanged();
//lastPosition = -1;
}
#Override
public int getCount() {
return 20;
}
#Override
public Object getItem(int position) {
return null;
}
#Override
public long getItemId(int position) {
return position;
}
#Override
public View getView(int position, View view, ViewGroup viewGroup) {
ViewHolder holder = null;
if (view == null) {
//The view is not a recycled one: we have to inflate
view = mLayoutInflater.inflate(R.layout.item_block.xml, viewGroup, false);
holder = new ViewHolder();
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
return view;
}
class ViewHolder {
/// Item Block views goes here...
}
}
Hopefully it will help you !!