implenented left and right layout

.idea/codeStyles/Project.xml

@@ -94,7 +94,6 @@
                   <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
                 </AND>
               </match>
-              <order>ANDROID_ATTRIBUTE_ORDER</order>
             </rule>
           </section>
           <section>

.idea/gradle.xml

@@ -1,15 +1,19 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
+  <component name="GradleMigrationSettings" migrationVersion="1" />
   <component name="GradleSettings">
     <option name="linkedExternalProjectsSettings">
       <GradleProjectSettings>
-        <compositeConfiguration>
+        <option name="testRunner" value="PLATFORM" />
-          <compositeBuild compositeDefinitionSource="SCRIPT" />
-        </compositeConfiguration>
         <option name="distributionType" value="DEFAULT_WRAPPED" />
         <option name="externalProjectPath" value="$PROJECT_DIR$" />
+        <option name="modules">
+          <set>
+            <option value="$PROJECT_DIR$" />
+            <option value="$PROJECT_DIR$/app" />
+          </set>
+        </option>
         <option name="resolveModulePerSourceSet" value="false" />
-        <option name="testRunner" value="PLATFORM" />
       </GradleProjectSettings>
     </option>
   </component>

.idea/jarRepositories.xml

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="RemoteRepositoriesConfiguration">
+    <remote-repository>
+      <option name="id" value="central" />
+      <option name="name" value="Maven Central repository" />
+      <option name="url" value="https://repo1.maven.org/maven2" />
+    </remote-repository>
+    <remote-repository>
+      <option name="id" value="jboss.community" />
+      <option name="name" value="JBoss Community repository" />
+      <option name="url" value="https://repository.jboss.org/nexus/content/repositories/public/" />
+    </remote-repository>
+    <remote-repository>
+      <option name="id" value="BintrayJCenter" />
+      <option name="name" value="BintrayJCenter" />
+      <option name="url" value="https://jcenter.bintray.com/" />
+    </remote-repository>
+    <remote-repository>
+      <option name="id" value="Google" />
+      <option name="name" value="Google" />
+      <option name="url" value="https://dl.google.com/dl/android/maven2/" />
+    </remote-repository>
+  </component>
+</project>

.idea/misc.xml

@@ -1,8 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_7" project-jdk-name="1.8" project-jdk-type="JavaSDK">
+  <component name="JavaScriptSettings">
-    <output url="file://$PROJECT_DIR$/build/classes" />
+    <option name="languageLevel" value="ES6" />
   </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" />
   </component>

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

@@ -5,13 +5,16 @@ import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
 
 import android.os.Bundle;
+import android.os.Handler;
 
 import java.util.ArrayList;
 import java.util.Date;
 
-public class MainActivity extends AppCompatActivity {
+public class MainActivity extends AppCompatActivity implements Runnable {
 
     ArrayList<Message> mData;
+    Handler mHandler;
+    MyAdapter myAdapter;
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -21,10 +24,29 @@ public class MainActivity extends AppCompatActivity {
         mData.add(new Message("Joel", "Eine super Nachricht", new Date()));
         mData.add(new Message("Max", "Eine Nachricht", new Date()));
 
-        MyAdapter myAdapter = new MyAdapter(mData);
+        myAdapter = new MyAdapter(mData);
         RecyclerView mRecyclerView = findViewById(R.id.recyclerView);
         LinearLayoutManager mLinearLayoutManager = new LinearLayoutManager(this);
         mRecyclerView.setLayoutManager(mLinearLayoutManager);
         mRecyclerView.setAdapter(myAdapter);
+        mHandler = new Handler();
+        mHandler.postDelayed(this, 1000);
+    }
+
+    @Override
+    public void run() {
+        int randNr = (int) Math.floor(Math.random() * 3);
+        switch (randNr){
+            case 0:
+                mData.add(new Message("Niklas", "Eine super duper Nachricht", new Date()));
+                break;
+            case 1:
+                mData.add(new Message("Joel", "Eine super Nachricht", new Date()));
+                break;
+            case 2:
+                mData.add(new Message("Max", "Eine Nachricht", new Date()));
+        }
+        myAdapter.notifyDataSetChanged();
+        mHandler.postDelayed(this, 1000);
     }
 }

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

@@ -1,5 +1,6 @@
 package com.example.recyclerview;
 
+import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
@@ -10,7 +11,7 @@ import androidx.recyclerview.widget.RecyclerView;
 
 import java.util.ArrayList;
 
-public class MyAdapter extends RecyclerView.Adapter<MyViewHolder> {
+public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
 
     ArrayList<Message> mData;
 
@@ -18,23 +19,51 @@ public class MyAdapter extends RecyclerView.Adapter<MyViewHolder> {
         mData = aData;
     }
 
+    @Override
+    public int getItemViewType(int position) {
+        return position % 2;
+    }
+
     @NonNull
     @Override
-    public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
+    public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
         LayoutInflater inflater = LayoutInflater.from(parent.getContext());
-        View newView = inflater.inflate(R.layout.message_layout, parent, false);
+        switch (viewType) {
-        MyViewHolder myViewHolder = new MyViewHolder(newView);
+            case 1:
-        return myViewHolder;
+                View newViewRight = inflater.inflate(R.layout.message_layout_right, parent, false);
+                return new MyViewHolderRight(newViewRight);
+            case 0:
+            default:
+                View newViewLeft = inflater.inflate(R.layout.message_layout_left, parent, false);
+                return new MyViewHolderLeft(newViewLeft);
+        }
     }
 
     @Override
-    public void onBindViewHolder(@NonNull MyViewHolder holder, int position) {
+    public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
-        TextView sender = holder.mTextView.findViewById(R.id.sender_tv);
+        TextView sender;
+        TextView text;
+        TextView date;
+        switch (holder.getItemViewType()) {
+            case 1:
+                MyViewHolderRight viewHolderRight = (MyViewHolderRight) holder;
+                sender = viewHolderRight.mLinearLayout.findViewById(R.id.sender_tv);
+                text = viewHolderRight.mLinearLayout.findViewById(R.id.text_tv);
+                date = viewHolderRight.mLinearLayout.findViewById(R.id.date_tv);
                 sender.setText(mData.get(position).sender);
-        TextView text = holder.mTextView.findViewById(R.id.text_tv);
                 text.setText(mData.get(position).text);
-        TextView date = holder.mTextView.findViewById(R.id.date_tv);
                 date.setText(mData.get(position).date.toString());
+                break;
+            case 0:
+            default:
+                MyViewHolderLeft viewHolderLeft = (MyViewHolderLeft) holder;
+                sender = viewHolderLeft.mLinearLayout.findViewById(R.id.sender_tv);
+                text = viewHolderLeft.mLinearLayout.findViewById(R.id.text_tv);
+                date = viewHolderLeft.mLinearLayout.findViewById(R.id.date_tv);
+                sender.setText(mData.get(position).sender);
+                text.setText(mData.get(position).text);
+                date.setText(mData.get(position).date.toString());
+        }
     }
 
     @Override

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

@@ -6,10 +6,10 @@ import android.widget.LinearLayout;
 import androidx.annotation.NonNull;
 import androidx.recyclerview.widget.RecyclerView;
 
-public class MyViewHolder extends RecyclerView.ViewHolder {
+public class MyViewHolderLeft extends RecyclerView.ViewHolder {
-    LinearLayout mTextView;
+    LinearLayout mLinearLayout;
-    public MyViewHolder(@NonNull View itemView) {
+    public MyViewHolderLeft(@NonNull View itemView) {
         super(itemView);
-        mTextView = (LinearLayout) itemView;
+        mLinearLayout = (LinearLayout) itemView;
     }
 }

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

@@ -0,0 +1,15 @@
+package com.example.recyclerview;
+
+import android.view.View;
+import android.widget.LinearLayout;
+
+import androidx.annotation.NonNull;
+import androidx.recyclerview.widget.RecyclerView;
+
+public class MyViewHolderRight extends RecyclerView.ViewHolder {
+    LinearLayout mLinearLayout;
+    public MyViewHolderRight(@NonNull View itemView) {
+        super(itemView);
+        mLinearLayout = (LinearLayout) itemView;
+    }
+}

app/src/main/res/layout/message_layout_left.xml

@@ -1,14 +1,20 @@
 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/message_layout_left"
     android:layout_width="match_parent"
     android:layout_height="100dp"
+    android:layout_marginLeft="10dp"
+    android:layout_marginRight="150dp"
     android:orientation="vertical">
 
     <TextView
         android:id="@+id/sender_tv"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:text="TextView" />
+        android:text="TextView"
+        android:textSize="18sp"
+        android:textStyle="bold"
+        android:typeface="normal" />
 
     <TextView
         android:id="@+id/text_tv"

app/src/main/res/layout/message_layout_right.xml

@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/message_layout_right"
+    android:layout_width="match_parent"
+    android:layout_height="100dp"
+    android:layout_marginLeft="150dp"
+    android:layout_marginRight="10dp"
+    android:orientation="vertical">
+
+    <TextView
+        android:id="@+id/sender_tv"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="TextView"
+        android:textSize="18sp"
+        android:textStyle="bold" />
+
+    <TextView
+        android:id="@+id/text_tv"
+        android:layout_width="match_parent"
+        android:layout_height="57dp"
+        android:text="TextView" />
+
+    <TextView
+        android:id="@+id/date_tv"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="TextView"
+        android:textAlignment="textEnd" />
+</LinearLayout>

build.gradle

@@ -7,7 +7,7 @@ buildscript {
         
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.5.2'
+        classpath 'com.android.tools.build:gradle:4.0.0-alpha08'
         
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Tue Jan 14 16:39:03 CET 2020
+#Sun Jan 19 10:43:18 CET 2020
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.4.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.1-rc-1-all.zip