[*] extract adapter class from main activity

app/src/main/java/com/danielkim/soundrecorder/activities/MainActivity.java

@@ -1,12 +1,7 @@
 package com.danielkim.soundrecorder.activities;
 
 import android.content.Intent;
-import android.content.SharedPreferences;
 import android.os.Bundle;
-import android.preference.PreferenceManager;
-import android.support.v4.app.Fragment;
-import android.support.v4.app.FragmentManager;
-import android.support.v4.app.FragmentPagerAdapter;
 import android.support.v4.view.ViewPager;
 import android.support.v7.app.ActionBarActivity;
 import android.support.v7.widget.Toolbar;
@@ -15,12 +10,10 @@
 
 import com.astuetz.PagerSlidingTabStrip;
 import com.danielkim.soundrecorder.R;
-import com.danielkim.soundrecorder.fragments.FileViewerFragment;
-import com.danielkim.soundrecorder.fragments.LicensesFragment;
-import com.danielkim.soundrecorder.fragments.RecordFragment;
+import com.danielkim.soundrecorder.adapters.FragmentsAdapter;
 
 
-public class MainActivity extends ActionBarActivity{
+public class MainActivity extends ActionBarActivity {
 
     private static final String LOG_TAG = MainActivity.class.getSimpleName();
 
@@ -32,8 +25,11 @@ protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
 
+        String[] titles = {getString(R.string.tab_title_record),
+                getString(R.string.tab_title_saved_recordings)};
+
         pager = (ViewPager) findViewById(R.id.pager);
-        pager.setAdapter(new MyAdapter(getSupportFragmentManager()));
+        pager.setAdapter(new FragmentsAdapter(getSupportFragmentManager(), titles));
         tabs = (PagerSlidingTabStrip) findViewById(R.id.tabs);
         tabs.setViewPager(pager);
 
@@ -67,38 +63,6 @@ public boolean onOptionsItemSelected(MenuItem item) {
         }
     }
 
-    public class MyAdapter extends FragmentPagerAdapter {
-        private String[] titles = { getString(R.string.tab_title_record),
-                getString(R.string.tab_title_saved_recordings) };
-
-        public MyAdapter(FragmentManager fm) {
-            super(fm);
-        }
-
-        @Override
-        public Fragment getItem(int position) {
-            switch(position){
-                case 0:{
-                    return RecordFragment.newInstance(position);
-                }
-                case 1:{
-                    return FileViewerFragment.newInstance(position);
-                }
-            }
-            return null;
-        }
-
-        @Override
-        public int getCount() {
-            return titles.length;
-        }
-
-        @Override
-        public CharSequence getPageTitle(int position) {
-            return titles[position];
-        }
-    }
-
     public MainActivity() {
     }
 }

app/src/main/java/com/danielkim/soundrecorder/adapters/FragmentsAdapter.java

@@ -0,0 +1,41 @@
+package com.danielkim.soundrecorder.adapters;
+
+import android.support.v4.app.Fragment;
+import android.support.v4.app.FragmentManager;
+import android.support.v4.app.FragmentPagerAdapter;
+
+import com.danielkim.soundrecorder.fragments.FileViewerFragment;
+import com.danielkim.soundrecorder.fragments.RecordFragment;
+
+public class FragmentsAdapter extends FragmentPagerAdapter {
+
+    private String[] mTitles;
+
+    public FragmentsAdapter(FragmentManager fm, String[] titles) {
+        super(fm);
+        this.mTitles = titles;
+    }
+
+    @Override
+    public Fragment getItem(int position) {
+        switch (position) {
+            case 0: {
+                return RecordFragment.newInstance(position);
+            }
+            case 1: {
+                return FileViewerFragment.newInstance(position);
+            }
+        }
+        return null;
+    }
+
+    @Override
+    public int getCount() {
+        return mTitles != null ? mTitles.length : 0;
+    }
+
+    @Override
+    public CharSequence getPageTitle(int position) {
+        return mTitles[position];
+    }
+}