T fragments.05 solution interface communication

app/src/main/AndroidManifest.xml

@@ -8,13 +8,18 @@
         android:label="@string/app_name"
         android:supportsRtl="true"
         android:theme="@style/AppTheme">
-        <activity android:name=".ui.AndroidMeActivity">
+
+        <!-- Declare the MainActivity in the manifest and set it to launch upon opening this app -->
+        <activity android:name=".ui.MainActivity" >
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+
+        <activity android:name=".ui.AndroidMeActivity" />
+
     </application>
 
 </manifest>

app/src/main/java/com/example/android/android_me/ui/AndroidMeActivity.java

@@ -16,29 +16,53 @@
 
 package com.example.android.android_me.ui;
 
+import android.support.v4.app.FragmentManager;
 import android.support.v7.app.AppCompatActivity;
 import android.os.Bundle;
 
 import com.example.android.android_me.R;
+import com.example.android.android_me.data.AndroidImageAssets;
 
 // This activity will display a custom Android image composed of three body parts: head, body, and legs
 public class AndroidMeActivity extends AppCompatActivity {
 
-    // TODO (1) Create a layout file that displays one body part image named fragment_body_part.xml
-        // This layout should contain a single ImageView
-
-    // TODO (2) Create a new class called BodyPartFragment to display an image of an Android-Me body part
-        // In this class, you'll need to implement an empty constructor and the onCreateView method
-        // TODO (3) Show the first image in the list of head images
-            // Soon, you'll update this image display code to show any image you want
-
-
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_android_me);
 
-        // TODO (5) Create a new BodyPartFragment instance and display it using the FragmentManager
+        // Only create new fragments when there is no previously saved state
+        if(savedInstanceState == null) {
+
+            // Create a new head BodyPartFragment
+            BodyPartFragment headFragment = new BodyPartFragment();
+
+            // Set the list of image id's for the head fragment and set the position to the second image in the list
+            headFragment.setImageIds(AndroidImageAssets.getHeads());
+            headFragment.setListIndex(1);
+
+            // Add the fragment to its container using a FragmentManager and a Transaction
+            FragmentManager fragmentManager = getSupportFragmentManager();
+
+            fragmentManager.beginTransaction()
+                    .add(R.id.head_container, headFragment)
+                    .commit();
+
+            // Create and display the body and leg BodyPartFragments
+
+            BodyPartFragment bodyFragment = new BodyPartFragment();
+            bodyFragment.setImageIds(AndroidImageAssets.getBodies());
+            fragmentManager.beginTransaction()
+                    .add(R.id.body_container, bodyFragment)
+                    .commit();
+
+            BodyPartFragment legFragment = new BodyPartFragment();
+            legFragment.setImageIds(AndroidImageAssets.getLegs());
+            fragmentManager.beginTransaction()
+                    .add(R.id.leg_container, legFragment)
+                    .commit();
+        }
+
     }
 }

app/src/main/java/com/example/android/android_me/ui/BodyPartFragment.java

@@ -0,0 +1,120 @@
+/*
+* Copyright (C) 2017 The Android Open Source Project
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*  	http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+package com.example.android.android_me.ui;
+
+import android.os.Bundle;
+import android.support.v4.app.Fragment;
+import android.util.Log;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ImageView;
+
+import com.example.android.android_me.R;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class BodyPartFragment extends Fragment {
+
+    // Final Strings to store state information about the list of images and list index
+    public static final String IMAGE_ID_LIST = "image_ids";
+    public static final String LIST_INDEX = "list_index";
+
+    // Tag for logging
+    private static final String TAG = "BodyPartFragment";
+
+    // Variables to store a list of image resources and the index of the image that this fragment displays
+    private List<Integer> mImageIds;
+    private int mListIndex;
+
+    /**
+     * Mandatory empty constructor for the fragment manager to instantiate the fragment
+     */
+    public BodyPartFragment() {
+    }
+
+    /**
+     * Inflates the fragment layout file and sets the correct resource for the image to display
+     */
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
+
+        // Load the saved state (the list of images and list index) if there is one
+        if(savedInstanceState != null) {
+            mImageIds = savedInstanceState.getIntegerArrayList(IMAGE_ID_LIST);
+            mListIndex = savedInstanceState.getInt(LIST_INDEX);
+        }
+
+        // Inflate the Android-Me fragment layout
+        View rootView = inflater.inflate(R.layout.fragment_body_part, container, false);
+
+        // Get a reference to the ImageView in the fragment layout
+        final ImageView imageView = (ImageView) rootView.findViewById(R.id.body_part_image_view);
+
+        // If a list of image ids exists, set the image resource to the correct item in that list
+        // Otherwise, create a Log statement that indicates that the list was not found
+        if(mImageIds != null){
+            // Set the image resource to the list item at the stored index
+            imageView.setImageResource(mImageIds.get(mListIndex));
+
+            // Set a click listener on the image view
+            imageView.setOnClickListener(new View.OnClickListener() {
+                @Override
+                public void onClick(View view) {
+                    // Increment position as long as the index remains <= the size of the image ids list
+                    if(mListIndex < mImageIds.size()-1) {
+                        mListIndex++;
+                    } else {
+                        // The end of list has been reached, so return to beginning index
+                        mListIndex = 0;
+                    }
+                    // Set the image resource to the new list item
+                    imageView.setImageResource(mImageIds.get(mListIndex));
+                }
+            });
+
+        } else {
+            Log.v(TAG, "This fragment has a null list of image id's");
+        }
+
+        // Return the rootView
+        return rootView;
+    }
+
+    // Setter methods for keeping track of the list images this fragment can display and which image
+    // in the list is currently being displayed
+
+    public void setImageIds(List<Integer> imageIds) {
+        mImageIds = imageIds;
+    }
+
+    public void setListIndex(int index) {
+        mListIndex = index;
+    }
+
+    /**
+     * Save the current state of this fragment
+     */
+    @Override
+    public void onSaveInstanceState(Bundle currentState) {
+        currentState.putIntegerArrayList(IMAGE_ID_LIST, (ArrayList<Integer>) mImageIds);
+        currentState.putInt(LIST_INDEX, mListIndex);
+    }
+
+
+}

app/src/main/java/com/example/android/android_me/ui/MainActivity.java

@@ -0,0 +1,43 @@
+/*
+* Copyright (C) 2017 The Android Open Source Project
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*  	http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+package com.example.android.android_me.ui;
+
+import android.os.Bundle;
+import android.support.v7.app.AppCompatActivity;
+import android.widget.Toast;
+
+import com.example.android.android_me.R;
+
+// This activity is responsible for displaying the master list of all images
+// Implement the MasterListFragment callback, OnImageClickListener
+public class MainActivity extends AppCompatActivity implements MasterListFragment.OnImageClickListener{
+
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_main);
+
+    }
+
+    // Define the behavior for onImageSelected
+    public void onImageSelected(int position) {
+        // Create a Toast that displays the position that was clicked
+        Toast.makeText(this, "Position clicked = " + position, Toast.LENGTH_SHORT).show();
+    }
+
+}

app/src/main/java/com/example/android/android_me/ui/MasterListFragment.java

@@ -0,0 +1,94 @@
+/*
+* Copyright (C) 2017 The Android Open Source Project
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*  	http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+package com.example.android.android_me.ui;
+
+import android.content.Context;
+import android.os.Bundle;
+import android.support.v4.app.Fragment;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.AdapterView;
+import android.widget.GridView;
+
+import com.example.android.android_me.R;
+import com.example.android.android_me.data.AndroidImageAssets;
+
+
+// This fragment displays all of the AndroidMe images in one large list
+// The list appears as a grid of images
+public class MasterListFragment extends Fragment {
+
+    // Define a new interface OnImageClickListener that triggers a callback in the host activity
+    OnImageClickListener mCallback;
+
+    // OnImageClickListener interface, calls a method in the host activity named onImageSelected
+    public interface OnImageClickListener {
+        void onImageSelected(int position);
+    }
+
+    // Override onAttach to make sure that the container activity has implemented the callback
+    @Override
+    public void onAttach(Context context) {
+        super.onAttach(context);
+
+        // This makes sure that the host activity has implemented the callback interface
+        // If not, it throws an exception
+        try {
+            mCallback = (OnImageClickListener) context;
+        } catch (ClassCastException e) {
+            throw new ClassCastException(context.toString()
+                    + " must implement OnImageClickListener");
+        }
+    }
+
+
+    // Mandatory empty constructor
+    public MasterListFragment() {
+    }
+
+    // Inflates the GridView of all AndroidMe images
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+                             Bundle savedInstanceState) {
+
+        final View rootView = inflater.inflate(R.layout.fragment_master_list, container, false);
+
+        // Get a reference to the GridView in the fragment_master_list xml layout file
+        GridView gridView = (GridView) rootView.findViewById(R.id.images_grid_view);
+
+        // Create the adapter
+        // This adapter takes in the context and an ArrayList of ALL the image resources to display
+        MasterListAdapter mAdapter = new MasterListAdapter(getContext(), AndroidImageAssets.getAll());
+
+        // Set the adapter on the GridView
+        gridView.setAdapter(mAdapter);
+
+        // Set a click listener on the gridView and trigger the callback onImageSelected when an item is clicked
+        gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
+            @Override
+            public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {
+                // Trigger the callback method and pass in the position that was clicked
+                mCallback.onImageSelected(position);
+            }
+        });
+
+        // Return the root view
+        return rootView;
+    }
+
+}

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

@@ -29,9 +29,24 @@
         android:paddingRight="@dimen/activity_horizontal_margin"
         android:paddingTop="@dimen/activity_vertical_margin">
 
-        <!-- TODO (4) Create a container to hold the head BodyPartFragment of the custom Android -->
-        <!--The container should be 180dp in height -->
 
+        <!-- Three containers for each Android-Me body part -->
+        <!-- This container holds the head BodyPartFragment of the custom Android-Me image -->
+        <FrameLayout android:id="@+id/head_container"
+        android:layout_width="match_parent"
+        android:layout_height="180dp"
+        android:scaleType="centerInside"/>
+
+        <!-- The remaining containers for the body and leg BodyPartFragments -->
+        <FrameLayout android:id="@+id/body_container"
+            android:layout_width="match_parent"
+            android:layout_height="180dp"
+            android:scaleType="centerInside"/>
+
+        <FrameLayout android:id="@+id/leg_container"
+            android:layout_width="match_parent"
+            android:layout_height="180dp"
+            android:scaleType="centerInside"/>
 
 
     </LinearLayout>

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

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--Copyright (C) 2017 The Android Open Source Project
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+  	http://www.apache.org/licenses/LICENSE-2.0
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.-->
+
+<!-- Display the static master list fragment -->
+<fragment
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/master_list_fragment"
+    android:name="com.example.android.android_me.ui.MasterListFragment"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent" />