Android: How to access toolbar from RecyclerViewHolder?

Question

Question

How can I access a toolbar and its children from a RecyclerViewHolder? I want to change the textView in my toolbar_main from RecyclerViewHolder with LongClick.

What I know

I know how to access the toolbar from my activty inside onCreate with

    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);
    getSupportActionBar().setDisplayShowTitleEnabled(false);
    txtTitle = (TextView) toolbar.findViewById(R.id.txtTitle);
    rbSelectAll = (RadioButton)toolbar.findViewById(R.id.rbSelectAll);
    rbSelectAll.setVisibility(GONE);
    txtTitle.setText("Gallerie");

RecyclerViewAdapter.java

public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewHolders> {

    private List<ItemObject> itemList;
    private Context context;
    private boolean isDir;

    public RecyclerViewAdapter(Context context, List<ItemObject> itemList, boolean isDir) {
        this.itemList = itemList;
        this.isDir = isDir;
        this.context = context;
    }

    @Override
    public RecyclerViewHolders onCreateViewHolder(ViewGroup parent, int viewType) {
        View layoutView = LayoutInflater.from(parent.getContext()).inflate(R.layout.card_view_list, null);
        RecyclerViewHolders rcv = new RecyclerViewHolders(layoutView, itemList, context);
        return rcv;
    }

    @Override
    public void onBindViewHolder(final RecyclerViewHolders holder, int position) {

        if(isDir){
            File[] fileNames = null;
            Log.v("Folder: ", itemList.get(position).getName());

            File path = new File(itemList.get(position).getName());
            if(path.exists()){
                fileNames = path.listFiles();
            }

            int i = 0;
            while(fileNames[i].isDirectory()){
                i++;
            }

            Glide.with(context).asBitmap()
                    .load(fileNames[i])
                    .thumbnail(0.2f)
                    .into(holder.countryPhoto);

            holder.selected.setVisibility(GONE);
            holder.albumName.setText(itemList.get(position).getName().substring(itemList.get(position).getName().lastIndexOf("/")+1));
            holder.countImages.setText(""+listFiles(itemList.get(position).getName()).size());

        }else {
            holder.selected.setVisibility(GONE);
            holder.albumName.setVisibility(GONE);
            holder.countImages.setVisibility(GONE);
            Glide.with(context).asBitmap()
                    .load(itemList.get(position).getName())
                    .thumbnail(0.2f)
                    .into(holder.countryPhoto);
        }
    }
}

RecyclerViewHolders.java

public class RecyclerViewHolders extends RecyclerView.ViewHolder implements View.OnClickListener, View.OnLongClickListener{

    public TextView albumName, countImages, txtName;
    public ImageView countryPhoto;
    private List<ItemObject> itemList;
    public RadioButton selected, selectAll;

    public RecyclerViewHolders(View itemView, List<ItemObject> itemList, Context context) {
        super(itemView);
        itemView.setOnClickListener(this);
        itemView.setOnLongClickListener(this);
        this.itemList = itemList;

        selected = (RadioButton)itemView.findViewById(R.id.rbSelected);
        albumName = (TextView)itemView.findViewById(R.id.albumName);
        countImages = (TextView)itemView.findViewById(R.id.countImages);
        countryPhoto = (ImageView)itemView.findViewById(R.id.country_photo);
    }

    @Override
    public void onClick(View view) {
        Toast.makeText(view.getContext(), "Clicked " + getPosition() + " " + itemList.get(getPosition()).getName(), Toast.LENGTH_SHORT).show();
    }

    @Override
    public boolean onLongClick(View view) {
        Toast.makeText(view.getContext(), "Long Clicked " + getPosition() + " " + itemList.get(getPosition()).getName(), Toast.LENGTH_SHORT).show();
        if(selected.isChecked()){
            selected.setVisibility(View.GONE);
            selected.setChecked(false);
        }else{
            selected.setVisibility(VISIBLE);
            selected.setChecked(true);
        }
        return true;
    }

}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<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:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.spicysoftware.myapplication.MainActivity">

    <include
        android:id="@+id/toolbarPictures"
        layout="@layout/toolbar_main"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

    <FrameLayout
        android:id="@+id/content"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1">

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:padding="8dp"
            tools:context=".MainActivity">

            <android.support.v7.widget.RecyclerView
                android:id="@+id/recycler_view"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:scrollbars="vertical" />

        </RelativeLayout>

    </FrameLayout>

    <android.support.design.widget.BottomNavigationView
        android:id="@+id/navigation"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:background="?android:attr/windowBackground"
        app:menu="@menu/navigation" />

</LinearLayout>

toolbar_main.xml

<?xml version="1.0" encoding="utf-8"?>
<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="match_parent">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appBarLayout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay">


        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="#5fb0c9"
            android:elevation="4dp"
            android:theme="@style/ThemeOverlay.AppCompat.ActionBar"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light">

            <TextView
                android:id="@+id/txtTitle"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="TextView"
                android:textColor="@android:color/white"
                android:textSize="18sp"
                android:textStyle="bold" />

        </android.support.v7.widget.Toolbar>
    </android.support.design.widget.AppBarLayout>
</LinearLayout>

Answer 1

Step 1: Create a class and Interface for RecyclerViewOnItemClick

RecyclerTouchListener.java

public class RecyclerTouchListener implements RecyclerView.OnItemTouchListener{

    private IOnRecyclerItemClickedListener clicklistener;
    private GestureDetector gestureDetector;

    public RecyclerTouchListener(Context context, final RecyclerView recycleView, final IOnRecyclerItemClickedListener clicklistener){

        this.clicklistener=clicklistener;
        gestureDetector=new GestureDetector(context,new GestureDetector.SimpleOnGestureListener(){
            @Override
            public boolean onSingleTapUp(MotionEvent e) {
                return true;
            }

            @Override
            public void onLongPress(MotionEvent e) {
                View child=recycleView.findChildViewUnder(e.getX(),e.getY());
                if(child!=null && clicklistener!=null){
                    clicklistener.onLongClick(child,recycleView.getChildAdapterPosition(child));
                }
            }
        });
    }

    @Override
    public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {
        View child=rv.findChildViewUnder(e.getX(),e.getY());
        if(child!=null && clicklistener!=null && gestureDetector.onTouchEvent(e)){
            clicklistener.onClick(child,rv.getChildAdapterPosition(child));
        }

        return false;
    }

    @Override
    public void onTouchEvent(RecyclerView rv, MotionEvent e) {

    }
    @Override
    public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {

    }
}

Interface IOnRecyclerItemClickedListener.java

public interface IOnRecyclerItemClickedListener {
    public void onRecyclerItemClick(View view, int position);
    public void onRecyclerItemLongClick(View view,int position);
}

Step 2: Implement IOnRecyclerItemClickedListener in your activity

YourActivity.java

public class YourActivity extends Fragment implements IOnRecyclerItemClickedListener{

private Toolbar toolbar;
@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        getSupportActionBar().setDisplayShowTitleEnabled(false);
        txtTitle = (TextView) toolbar.findViewById(R.id.txtTitle);
        rbSelectAll = (RadioButton)toolbar.findViewById(R.id.rbSelectAll);
    rbSelectAll.setVisibility(GONE);
    txtTitle.setText("Gallerie");
    }

@Override
    public void onRecyclerItemLongClick(View view, int position) {
       toolbar.setTitle("Title that you want to display");
    }


    @Override
    public void onRecyclerItemClick(View v) {

        }
    }
}

I hope this answer will help you!!

Answer 2

((MainActivity) context).toolbar

Or ((MainActivity) context).findViewById(R.id.toolbar)

Answer 3

You can use interface to achieve your goal as shown below.

Create an interface.

public interface DummyInterface {
    public void doSomethingWithToolbar();
}

Then implement this interface on your activity.

public class DummyActivity extends Activity implements DummyInterface {
    .
    .
    .
    public void doSomethingWithToolbar() {
        //do something with toolbar
    }
}

Then pass the reference of this(activity) when creating recycler view in constructor. Like,

new DummyRecyclerView(..., this);

Then add a parameter in RecyclerView's constructor. Like,

DummyInterface dummy = new DummyInterface();
public DummyRecyclerView(..., DummyInterface d) {
    dummy = d;
}

Then pass dummy to the RecyclerViewHolder's constructor and add that to parameter in constructor of RecyclerViewHolder same way we have done from Activity to RecyclerView. And you can call the method doSomethingWithToolbar from RecyclerViewHolder using dummy.doSomethingWithToolbar().

Answer 4

You shouldn't couple two entirely separate Views. You should define an onLongClick interface that your Activity should implement and you set it on each and every itemView inside of the constructor for your ViewHolder then do your Toolbar functionality.