From 0713ed9e12c3e535a887337164da7b5dc60541b2 Mon Sep 17 00:00:00 2001
From: Vivek Maskara <maskaravivek@hotmail.com>
Date: Sun, 2 Apr 2017 22:08:14 +0530
Subject: [PATCH] Refactored welcome activity to decouple the view pager (#481)

---
 .../fr/free/nrw/commons/WelcomeActivity.java  | 64 +++--------------
 .../free/nrw/commons/WelcomePagerAdapter.java | 72 +++++++++++++++++++
 2 files changed, 83 insertions(+), 53 deletions(-)
 create mode 100644 app/src/main/java/fr/free/nrw/commons/WelcomePagerAdapter.java

diff --git a/app/src/main/java/fr/free/nrw/commons/WelcomeActivity.java b/app/src/main/java/fr/free/nrw/commons/WelcomeActivity.java
index 2345126a0..30c8baf84 100644
--- a/app/src/main/java/fr/free/nrw/commons/WelcomeActivity.java
+++ b/app/src/main/java/fr/free/nrw/commons/WelcomeActivity.java
@@ -1,32 +1,19 @@
 package fr.free.nrw.commons;
 
 import android.os.Bundle;
-import android.support.v4.view.PagerAdapter;
 import android.support.v4.view.ViewPager;
-import android.view.View;
-import android.view.ViewGroup;
-import android.widget.Button;
 
 import com.viewpagerindicator.CirclePageIndicator;
 
+import butterknife.BindView;
+import butterknife.ButterKnife;
 import fr.free.nrw.commons.theme.BaseActivity;
 
 public class WelcomeActivity extends BaseActivity {
-    static final int PAGE_WIKIPEDIA = 0,
-            PAGE_DO_UPLOAD = 1,
-            PAGE_DONT_UPLOAD = 2,
-            PAGE_IMAGE_DETAILS = 3,
-            PAGE_FINAL = 4;
-    static final int[] pageLayouts = new int[] {
-            R.layout.welcome_wikipedia,
-            R.layout.welcome_do_upload,
-            R.layout.welcome_dont_upload,
-            R.layout.welcome_image_details,
-            R.layout.welcome_final
-    };
+    private WelcomePagerAdapter adapter;
 
-    private ViewPager pager;
-    private Button yesButton;
+    @BindView(R.id.welcomePager) ViewPager pager;
+    @BindView(R.id.welcomePagerIndicator) CirclePageIndicator indicator;
 
     @Override
     public void onCreate(Bundle savedInstanceState) {
@@ -34,43 +21,14 @@ public class WelcomeActivity extends BaseActivity {
         setContentView(R.layout.activity_welcome);
 
         getSupportActionBar().hide();
+        ButterKnife.bind(this);
 
-        pager = (ViewPager)findViewById(R.id.welcomePager);
-        pager.setAdapter(new PagerAdapter() {
-            @Override
-            public int getCount() {
-                return pageLayouts.length;
-            }
+        setUpAdapter();
+    }
 
-            @Override
-            public boolean isViewFromObject(View view, Object o) {
-                return (view == o);
-            }
-
-            @Override
-            public Object instantiateItem(ViewGroup container, int position) {
-                View view = getLayoutInflater().inflate(pageLayouts[position], null);
-                container.addView(view);
-                if (position == PAGE_FINAL) {
-                    yesButton = (Button)view.findViewById(R.id.welcomeYesButton);
-                    yesButton.setOnClickListener(new View.OnClickListener() {
-                        @Override
-                        public void onClick(View view) {
-                            finish();
-                        }
-                    });
-                }
-                return view;
-            }
-
-            @Override
-            public void destroyItem(ViewGroup container, int position, Object obj) {
-                yesButton = null;
-                container.removeView((View)obj);
-            }
-        });
-
-        CirclePageIndicator indicator = (CirclePageIndicator)findViewById(R.id.welcomePagerIndicator);
+    private void setUpAdapter() {
+        adapter = new WelcomePagerAdapter(this);
+        pager.setAdapter(adapter);
         indicator.setViewPager(pager);
     }
 }
diff --git a/app/src/main/java/fr/free/nrw/commons/WelcomePagerAdapter.java b/app/src/main/java/fr/free/nrw/commons/WelcomePagerAdapter.java
new file mode 100644
index 000000000..6da880694
--- /dev/null
+++ b/app/src/main/java/fr/free/nrw/commons/WelcomePagerAdapter.java
@@ -0,0 +1,72 @@
+package fr.free.nrw.commons;
+
+import android.app.Activity;
+import android.content.Context;
+import android.support.v4.view.PagerAdapter;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+import butterknife.ButterKnife;
+import butterknife.OnClick;
+
+public class WelcomePagerAdapter extends PagerAdapter {
+
+    private Context context;
+
+    private static final int PAGE_FINAL = 4;
+
+    static final int[] PAGE_LAYOUTS = new int[]{
+            R.layout.welcome_wikipedia,
+            R.layout.welcome_do_upload,
+            R.layout.welcome_dont_upload,
+            R.layout.welcome_image_details,
+            R.layout.welcome_final
+    };
+
+    public WelcomePagerAdapter(Context context) {
+        this.context = context;
+    }
+
+    @Override
+    public int getCount() {
+        return PAGE_LAYOUTS.length;
+    }
+
+    @Override
+    public boolean isViewFromObject(View view, Object object) {
+        return (view == object);
+    }
+
+    @Override
+    public Object instantiateItem(ViewGroup container, int position) {
+        LayoutInflater inflater = LayoutInflater.from(context);
+        ViewGroup layout = (ViewGroup) inflater.inflate(PAGE_LAYOUTS[position], container, false);
+
+        if (position == PAGE_FINAL) {
+            ViewHolder holder = new ViewHolder(layout, context);
+            layout.setTag(holder);
+        }
+        container.addView(layout);
+        return layout;
+    }
+
+    @Override
+    public void destroyItem(ViewGroup container, int position, Object obj) {
+        container.removeView((View) obj);
+    }
+
+    public static class ViewHolder {
+        private Context context;
+
+        public ViewHolder(View view, Context context) {
+            ButterKnife.bind(this, view);
+            this.context = context;
+        }
+
+        @OnClick(R.id.welcomeYesButton)
+        void onClicked() {
+            ((Activity) context).finish();
+        }
+    }
+}