Adapter with position dependent types; example animation;

README.md

@@ -0,0 +1,7 @@
+GridLayoutManager with different view types flickering
+
+![Grid](pictures/grid.gif "Grid")
+
+LinearLayoutManager with position dependent view types
+
+![Grid](pictures/linear.gif "Grid")

app/build.gradle

@@ -1,13 +1,13 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 24
-    buildToolsVersion "24.0.1"
+    compileSdkVersion 23
+    buildToolsVersion "23.0.3"
 
     defaultConfig {
         applicationId "ru.rma.androiddraganddropexample"
         minSdkVersion 14
-        targetSdkVersion 24
+        targetSdkVersion 23
         versionCode 1
         versionName "1.0"
     }
@@ -21,6 +21,6 @@ android {
 
 dependencies {
     compile fileTree(include: ['*.jar'], dir: 'libs')
-    compile 'com.android.support:appcompat-v7:24.1.0'
-    compile 'com.android.support:recyclerview-v7:24.1.0'
+    compile 'com.android.support:appcompat-v7:23.2.1'
+    compile 'com.android.support:recyclerview-v7:23.2.1'
 }

app/src/main/java/ru/rma/androiddraganddropexample/ItemAdapter.java

@@ -55,7 +55,7 @@ public ItemViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
                 view = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item_type_10, parent, false);
                 break;
             default:
-                throw new RuntimeException("Unknow view type: " + viewType);
+                throw new RuntimeException("Unknown view type: " + viewType);
         }
         return new ItemViewHolder(view);
     }

app/src/main/java/ru/rma/androiddraganddropexample/MainActivity.java

@@ -4,6 +4,7 @@
 import android.support.v4.app.ActivityCompat;
 import android.support.v7.app.AppCompatActivity;
 import android.os.Bundle;
+import android.support.v7.widget.RecyclerView;
 import android.view.View;
 
 
@@ -37,14 +38,23 @@ public void onClick(View view) {
             case R.id.btn_staggeredGridDiff:
                 startRecyclerViewActivity(RecyclerViewActivity.LAYOUT_MANAGER_STAGGERED_GRID, true);
                 break;
+            case R.id.btn_linearPositionDependentTypes:
+                startRecyclerViewActivity(RecyclerViewActivity.LAYOUT_MANAGER_LINEAR, true, true);
+                break;
         }
     }
 
 
     private void startRecyclerViewActivity(int layoutManagerType, boolean diffViewTypes) {
+        startRecyclerViewActivity(layoutManagerType, diffViewTypes, false);
+    }
+
+    private void startRecyclerViewActivity(int layoutManagerType, boolean diffViewTypes,
+                                           boolean typesPosDependent) {
         Intent intent = new Intent(this, RecyclerViewActivity.class);
         intent.putExtra(RecyclerViewActivity.KEY_LAYOUT_MANAGER_TYPE, layoutManagerType);
         intent.putExtra(RecyclerViewActivity.KEY_DIFFERENT_VIEW_TYPES, diffViewTypes);
+        intent.putExtra(RecyclerViewActivity.KEY_TYPES_POS_DEPENDENT, typesPosDependent);
         ActivityCompat.startActivity(this, intent, null);
     }
 }

app/src/main/java/ru/rma/androiddraganddropexample/PositionTypeAdapter.java

@@ -0,0 +1,22 @@
+package ru.rma.androiddraganddropexample;
+
+import android.support.annotation.NonNull;
+
+import java.util.List;
+
+public class PositionTypeAdapter extends ItemAdapter {
+    public PositionTypeAdapter(@NonNull List<ItemModel> items) {
+        super(items);
+    }
+
+    @Override
+    public int getItemViewType(int position) {
+        if(position == 0) {
+            return R.id.item_type_1;
+        } else if(position == getItemCount() - 1) {
+            return R.id.item_type_2;
+        } else {
+            return R.id.item_type_3;
+        }
+    }
+}

app/src/main/java/ru/rma/androiddraganddropexample/RecyclerViewActivity.java

@@ -1,6 +1,5 @@
 package ru.rma.androiddraganddropexample;
 
-import android.content.Intent;
 import android.os.Bundle;
 import android.support.v7.app.ActionBar;
 import android.support.v7.app.AppCompatActivity;
@@ -18,6 +17,7 @@ public class RecyclerViewActivity extends AppCompatActivity {
 
     public static final String KEY_DIFFERENT_VIEW_TYPES = "ru.rma.androiddraganddropexample.RecyclerViewActivity.KEY_DIFFERENT_VIEW_TYPES";
     public static final String KEY_LAYOUT_MANAGER_TYPE = "ru.rma.androiddraganddropexample.RecyclerViewActivity.KEY_LAYOUT_MANAGER_TYPE";
+    public static final String KEY_TYPES_POS_DEPENDENT = "ru.rma.androiddraganddropexample.RecyclerViewActivity.KEY_TYPES_POS_DEPENDENT";
     public static final int LAYOUT_MANAGER_LINEAR = 1;
     public static final int LAYOUT_MANAGER_GRID = 2;
     public static final int LAYOUT_MANAGER_STAGGERED_GRID = 3;
@@ -27,7 +27,8 @@ public class RecyclerViewActivity extends AppCompatActivity {
 
 
     private int mLayoutManagerType;
-    private boolean isDifferentViewTypes;
+    private boolean mIsDifferentViewTypes;
+    private boolean mTypesPosDependent;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -39,19 +40,19 @@ protected void onCreate(Bundle savedInstanceState) {
             ab.setDisplayHomeAsUpEnabled(true);
         }
 
-        Intent intent = getIntent();
-        if (savedInstanceState != null) {
-            isDifferentViewTypes = savedInstanceState.getBoolean(KEY_DIFFERENT_VIEW_TYPES, true);
-            mLayoutManagerType = savedInstanceState.getInt(KEY_LAYOUT_MANAGER_TYPE, LAYOUT_MANAGER_LINEAR);
-        } else if (intent != null) {
-            isDifferentViewTypes = intent.getBooleanExtra(KEY_DIFFERENT_VIEW_TYPES, true);
-            mLayoutManagerType = intent.getIntExtra(KEY_LAYOUT_MANAGER_TYPE, LAYOUT_MANAGER_LINEAR);
+        Bundle bundle = savedInstanceState != null ? savedInstanceState : getIntent().getExtras();
+        if (bundle != null) {
+            mIsDifferentViewTypes = bundle.getBoolean(KEY_DIFFERENT_VIEW_TYPES, true);
+            mLayoutManagerType = bundle.getInt(KEY_LAYOUT_MANAGER_TYPE, LAYOUT_MANAGER_LINEAR);
+            mTypesPosDependent = bundle.getBoolean(KEY_TYPES_POS_DEPENDENT, false);
         } else {
-            isDifferentViewTypes = true;
+            mIsDifferentViewTypes = true;
             mLayoutManagerType = LAYOUT_MANAGER_LINEAR;
+            mTypesPosDependent = false;
         }
-
-        ItemAdapter adapter = new ItemAdapter(createItemList());
+        List<ItemModel> models = createItemList();
+        ItemAdapter adapter = mTypesPosDependent ? new PositionTypeAdapter(models) :
+                new ItemAdapter(models);
         RecyclerView rv = (RecyclerView) findViewById(R.id.rv_list);
         switch (mLayoutManagerType) {
             case LAYOUT_MANAGER_GRID:
@@ -76,13 +77,15 @@ protected void onSaveInstanceState(Bundle outState) {
         super.onSaveInstanceState(outState);
 
         outState.putInt(KEY_LAYOUT_MANAGER_TYPE, mLayoutManagerType);
+        outState.putBoolean(KEY_DIFFERENT_VIEW_TYPES, mIsDifferentViewTypes);
+        outState.putBoolean(KEY_TYPES_POS_DEPENDENT, mTypesPosDependent);
     }
 
 
     private List<ItemModel> createItemList() {
         List<ItemModel> list = new ArrayList<>();
 
-        if (isDifferentViewTypes) {
+        if (mIsDifferentViewTypes) {
             list.add(new ItemModel(R.id.item_type_1, "1"));
             list.add(new ItemModel(R.id.item_type_2, "2"));
             list.add(new ItemModel(R.id.item_type_3, "3"));

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

@@ -62,4 +62,13 @@
         android:onClick="onClick"
         android:text="Staggered Grid Layout Manager Diff"
         android:gravity="center_vertical|start"/>
+
+    <Button
+        android:id="@+id/btn_linearPositionDependentTypes"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_below="@id/btn_staggeredGridDiff"
+        android:onClick="onClick"
+        android:text="Linear Layout Manager with pos dependent types"
+        android:gravity="center_vertical|start"/>
 </RelativeLayout>