implemented onClick method

.idea/misc.xml

@@ -3,6 +3,45 @@
   <component name="JavaScriptSettings">
     <option name="languageLevel" value="ES6" />
   </component>
+  <component name="NullableNotNullManager">
+    <option name="myDefaultNullable" value="org.jetbrains.annotations.Nullable" />
+    <option name="myDefaultNotNull" value="androidx.annotation.NonNull" />
+    <option name="myNullables">
+      <value>
+        <list size="12">
+          <item index="0" class="java.lang.String" itemvalue="org.jetbrains.annotations.Nullable" />
+          <item index="1" class="java.lang.String" itemvalue="javax.annotation.Nullable" />
+          <item index="2" class="java.lang.String" itemvalue="javax.annotation.CheckForNull" />
+          <item index="3" class="java.lang.String" itemvalue="edu.umd.cs.findbugs.annotations.Nullable" />
+          <item index="4" class="java.lang.String" itemvalue="android.support.annotation.Nullable" />
+          <item index="5" class="java.lang.String" itemvalue="androidx.annotation.Nullable" />
+          <item index="6" class="java.lang.String" itemvalue="android.annotation.Nullable" />
+          <item index="7" class="java.lang.String" itemvalue="androidx.annotation.RecentlyNullable" />
+          <item index="8" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.qual.Nullable" />
+          <item index="9" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.compatqual.NullableDecl" />
+          <item index="10" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.compatqual.NullableType" />
+          <item index="11" class="java.lang.String" itemvalue="com.android.annotations.Nullable" />
+        </list>
+      </value>
+    </option>
+    <option name="myNotNulls">
+      <value>
+        <list size="11">
+          <item index="0" class="java.lang.String" itemvalue="org.jetbrains.annotations.NotNull" />
+          <item index="1" class="java.lang.String" itemvalue="javax.annotation.Nonnull" />
+          <item index="2" class="java.lang.String" itemvalue="edu.umd.cs.findbugs.annotations.NonNull" />
+          <item index="3" class="java.lang.String" itemvalue="android.support.annotation.NonNull" />
+          <item index="4" class="java.lang.String" itemvalue="androidx.annotation.NonNull" />
+          <item index="5" class="java.lang.String" itemvalue="android.annotation.NonNull" />
+          <item index="6" class="java.lang.String" itemvalue="androidx.annotation.RecentlyNonNull" />
+          <item index="7" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.qual.NonNull" />
+          <item index="8" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.compatqual.NonNullDecl" />
+          <item index="9" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.compatqual.NonNullType" />
+          <item index="10" class="java.lang.String" itemvalue="com.android.annotations.NonNull" />
+        </list>
+      </value>
+    </option>
+  </component>
   <component name="ProjectRootManager" version="2" languageLevel="JDK_1_7" project-jdk-name="1.8" project-jdk-type="JavaSDK" />
   <component name="ProjectType">
     <option name="id" value="Android" />

app/src/main/java/com/example/recyclerview/MainActivity.java

@@ -6,11 +6,13 @@ import androidx.recyclerview.widget.RecyclerView;
 
 import android.os.Bundle;
 import android.os.Handler;
+import android.view.View;
+import android.widget.AdapterView;
 
 import java.util.ArrayList;
 import java.util.Date;
 
-public class MainActivity extends AppCompatActivity implements Runnable {
+public class MainActivity extends AppCompatActivity implements Runnable, AdapterView.OnItemClickListener {
 
     ArrayList<Message> mData;
     Handler mHandler;
@@ -26,6 +28,17 @@ public class MainActivity extends AppCompatActivity implements Runnable {
 
         myAdapter = new MyAdapter(mData);
         RecyclerView mRecyclerView = findViewById(R.id.recyclerView);
+        mRecyclerView.addOnItemTouchListener(
+                new RecyclerItemClickListener(getApplicationContext(), mRecyclerView ,new RecyclerItemClickListener.OnItemClickListener() {
+                    @Override public void onItemClick(View view, int position) {
+                        System.out.println("clicked " + mData.get(position).sender);
+                    }
+
+                    @Override public void onLongItemClick(View view, int position) {
+                        // do whatever
+                    }
+                })
+        );
         LinearLayoutManager mLinearLayoutManager = new LinearLayoutManager(this);
         mRecyclerView.setLayoutManager(mLinearLayoutManager);
         mRecyclerView.setAdapter(myAdapter);
@@ -49,4 +62,9 @@ public class MainActivity extends AppCompatActivity implements Runnable {
         myAdapter.notifyDataSetChanged();
         mHandler.postDelayed(this, 1000);
     }
+
+    @Override
+    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
+        System.out.println("gecklickt ".concat(mData.get(position).sender));
+    }
 }

app/src/main/java/com/example/recyclerview/RecyclerItemClickListener.java

@@ -0,0 +1,54 @@
+package com.example.recyclerview;
+
+import android.content.Context;
+import android.view.GestureDetector;
+import android.view.MotionEvent;
+import android.view.View;
+
+import androidx.annotation.NonNull;
+import androidx.recyclerview.widget.RecyclerView;
+
+
+public class RecyclerItemClickListener implements RecyclerView.OnItemTouchListener {
+    private OnItemClickListener mListener;
+
+    public interface OnItemClickListener {
+        void onItemClick(View view, int position);
+
+        void onLongItemClick(View view, int position);
+    }
+
+    private GestureDetector mGestureDetector;
+
+    RecyclerItemClickListener(Context context, final RecyclerView recyclerView, OnItemClickListener listener) {
+        mListener = listener;
+        mGestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
+            @Override
+            public boolean onSingleTapUp(MotionEvent e) {
+                return true;
+            }
+
+            @Override
+            public void onLongPress(MotionEvent e) {
+                View child = recyclerView.findChildViewUnder(e.getX(), e.getY());
+                if (child != null && mListener != null) {
+                    mListener.onLongItemClick(child, recyclerView.getChildAdapterPosition(child));
+                }
+            }
+        });
+    }
+
+    @Override public boolean onInterceptTouchEvent(RecyclerView view, MotionEvent e) {
+        View childView = view.findChildViewUnder(e.getX(), e.getY());
+        if (childView != null && mListener != null && mGestureDetector.onTouchEvent(e)) {
+            mListener.onItemClick(childView, view.getChildAdapterPosition(childView));
+            return true;
+        }
+        return false;
+    }
+
+    @Override public void onTouchEvent(@NonNull RecyclerView view, @NonNull MotionEvent motionEvent) { }
+
+    @Override
+    public void onRequestDisallowInterceptTouchEvent (boolean disallowIntercept){}
+}