mvp: Introducing Model View Presenter pattern

libringclient is a new module where we will put avery non Android code.
MVP must not depend on Android.

app now depends on that module. It should improve reusability.

Change-Id: I20c7d7adeed43212a21e5e617e6d2b6054db8a40
Tuleap: #1217
diff --git a/ring-android/libringclient/.gitignore b/ring-android/libringclient/.gitignore
new file mode 100644
index 0000000..796b96d
--- /dev/null
+++ b/ring-android/libringclient/.gitignore
@@ -0,0 +1 @@
+/build
diff --git a/ring-android/libringclient/build.gradle b/ring-android/libringclient/build.gradle
new file mode 100644
index 0000000..49df001
--- /dev/null
+++ b/ring-android/libringclient/build.gradle
@@ -0,0 +1,8 @@
+apply plugin: 'java'
+
+dependencies {
+    compile fileTree(dir: 'libs', include: ['*.jar'])
+}
+
+sourceCompatibility = "1.7"
+targetCompatibility = "1.7"
diff --git a/ring-android/libringclient/src/main/java/cx/ring/mvp/RootPresenter.java b/ring-android/libringclient/src/main/java/cx/ring/mvp/RootPresenter.java
new file mode 100644
index 0000000..f3cd758
--- /dev/null
+++ b/ring-android/libringclient/src/main/java/cx/ring/mvp/RootPresenter.java
@@ -0,0 +1,50 @@
+/*
+ *  Copyright (C) 2016 Savoir-faire Linux Inc.
+ *
+ *  Author: Thibault Wittemberg <thibault.wittemberg@savoirfairelinux.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+package cx.ring.mvp;
+
+import java.lang.ref.WeakReference;
+
+public class RootPresenter<T> {
+
+    private WeakReference<T> mView;
+
+    public void bindView(T view) {
+        mView = new WeakReference<>(view);
+    }
+
+    public void unbindView() {
+        if (mView != null) {
+            mView.clear();
+        }
+
+        mView = null;
+    }
+
+    public T getView() {
+        if (mView != null) {
+            return mView.get();
+        }
+
+        return null;
+    }
+
+}
+
+