Implement Android intent handling in qml app

AndroidManifest.xml register activity as an handler for retroshare links
RetroShareQmlActivity...NativeCalls.cpp bring the intent data from java
  to C++ and then to QML
QMl mainWindow uses URI.js to parse the received uri
Create a singleton for qml engine so it is reachable from NativeCalls

retroshare-qml-app/src/android/AndroidManifest.xml

@@ -10,16 +10,24 @@
                   android:label="RetroShare QML"
                   android:configChanges="orientation|uiMode|screenLayout|screenSize|smallestScreenSize|layoutDirection|locale|fontScale|keyboard|keyboardHidden|navigation"
                   android:screenOrientation="unspecified"
-                  android:launchMode="singleTop">
+                  android:launchMode="singleTask">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>
                 <category android:name="android.intent.category.LAUNCHER"/>
             </intent-filter>
 
-            <!-- Application to launch -->
-            <meta-data android:name="android.app.lib_name" android:value="retroshare-qml-app"/>
-            <!-- Application to launch -->
+            <!-- Register for retroshare:// and rtsh:// link handling -->
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW"/>
+                <category android:name="android.intent.category.DEFAULT"/>
+                <category android:name="android.intent.category.BROWSABLE"/>
+                <data android:scheme="retroshare" />
+                <data android:scheme="rtsh" />
+            </intent-filter>
 
+            <!-- Qt Application to launch -->
+            <meta-data android:name="android.app.lib_name"
+                       android:value="retroshare-qml-app"/>
             <!-- Application arguments -->
             <!-- meta-data android:name="android.app.arguments" android:value="arg1 arg2 arg3"/ -->
             <!-- Application arguments -->

retroshare-qml-app/src/android/src/NativeCalls.cpp

@@ -0,0 +1,46 @@
+/*
+ * RetroShare Android QML App
+ * Copyright (C) 2017  Gioacchino Mazzurco <gio@eigenlab.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "NativeCalls.h"
+#include "singletonqmlengine.h"
+
+#include <QString>
+#include <QQmlApplicationEngine>
+#include <QMetaObject>
+#include <QDebug>
+#include <QQuickWindow>
+
+JNIEXPORT void JNICALL
+Java_org_retroshare_android_qml_1app_jni_NativeCalls_notifyIntentUri
+(JNIEnv* env, jclass, jstring uri)
+{
+	const char *uriBytes = env->GetStringUTFChars(uri, NULL);
+	QString uriStr(uriBytes);
+	env->ReleaseStringUTFChars(uri, uriBytes);
+
+	QQmlApplicationEngine& engine(SingletonQmlEngine::instance());
+	QObject* rootObj = engine.rootObjects()[0];
+	QQuickWindow* mainWindow = qobject_cast<QQuickWindow*>(rootObj);
+
+	if(mainWindow)
+	{
+		QMetaObject::invokeMethod(mainWindow, "handleIntentUri",
+		                          Q_ARG(QVariant, uriStr));
+	}
+	else qCritical() << __PRETTY_FUNCTION__ << "Root object is not a window!";
+}

retroshare-qml-app/src/android/src/org/retroshare/android/qml_app/RetroShareQmlActivity.java

@@ -26,6 +26,8 @@ import android.util.Log;
 
 import org.qtproject.qt5.android.bindings.QtActivity;
 
+import org.retroshare.android.qml_app.jni.NativeCalls;
+
 public class RetroShareQmlActivity extends QtActivity
 {
 	@Override
@@ -50,6 +52,18 @@ public class RetroShareQmlActivity extends QtActivity
 		super.onCreate(savedInstanceState);
 	}
 
+	@Override
+	public void onNewIntent(Intent intent)
+	{
+		super.onNewIntent(intent);
+		String uri = intent.getDataString();
+		if (uri != null)
+		{
+			Log.d("RetroShareQmlActivity", "onNewIntent() " + uri);
+			NativeCalls.notifyIntentUri(uri);
+		}
+	}
+
 	private boolean isMyServiceRunning(Class<?> serviceClass)
 	{
 		ActivityManager manager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);

retroshare-qml-app/src/android/src/org/retroshare/android/qml_app/jni/NativeCalls.java

@@ -0,0 +1,24 @@
+/*
+ * RetroShare Android Service
+ * Copyright (C) 2017  Gioacchino Mazzurco <gio@eigenlab.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.retroshare.android.qml_app.jni;
+
+public class NativeCalls
+{
+	public static native void notifyIntentUri(String uri);
+}

retroshare-qml-app/src/android/src/org_retroshare_android_qml_app_jni_NativeCalls.h

@@ -0,0 +1,21 @@
+/* DO NOT EDIT THIS FILE - it is machine generated */
+#include <jni.h>
+/* Header for class org_retroshare_android_qml_app_jni_NativeCalls */
+
+#ifndef _Included_org_retroshare_android_qml_app_jni_NativeCalls
+#define _Included_org_retroshare_android_qml_app_jni_NativeCalls
+#ifdef __cplusplus
+extern "C" {
+#endif
+/*
+ * Class:     org_retroshare_android_qml_app_jni_NativeCalls
+ * Method:    notifyIntentUri
+ * Signature: (Ljava/lang/String;)V
+ */
+JNIEXPORT void JNICALL Java_org_retroshare_android_qml_1app_jni_NativeCalls_notifyIntentUri
+  (JNIEnv *, jclass, jstring);
+
+#ifdef __cplusplus
+}
+#endif
+#endif