Added example with proper handling of Android application permissions for QZXingLive triggered by #22

.gitignore

@@ -22,3 +22,6 @@ debug/
 *.sln
 *.suo
 *.vcxproj*
+.gradle
+.idea
+.build

examples/QZXingLive/QZXingLive.pro

@@ -4,7 +4,18 @@ QT += qml quick
 
 CONFIG += c++11 qzxing_multimedia
 
-SOURCES += main.cpp
+CONFIG(debug, debug|release) {
+    CONFIG+=qml_debug
+} else {
+    DEFINES += QT_NO_DEBUG
+    DEFINES += QT_NO_DEBUG_OUTPUT
+}
+
+HEADERS += \
+    application.h
+
+SOURCES += main.cpp \
+    application.cpp
 
 RESOURCES += qml.qrc
 
@@ -16,20 +27,30 @@ include(../../src/QZXing.pri)
 # Default rules for deployment.
 include(deployment.pri)
 
-DISTFILES += \
-    android/AndroidManifest.xml \
-    android/gradle/wrapper/gradle-wrapper.jar \
-    android/gradlew \
-    android/res/values/libs.xml \
-    android/build.gradle \
-    android/gradle/wrapper/gradle-wrapper.properties \
-    android/gradlew.bat \
-    android/AndroidManifest.xml \
-    android/gradle/wrapper/gradle-wrapper.jar \
-    android/gradlew \
-    android/res/values/libs.xml \
-    android/build.gradle \
-    android/gradle/wrapper/gradle-wrapper.properties \
-    android/gradlew.bat
+android {
+    QT += androidextras
 
-ANDROID_PACKAGE_SOURCE_DIR = $$PWD/android
+    HEADERS += \
+        native.h
+
+    SOURCES +=  \
+        native.cpp
+
+    DISTFILES += \
+        android/AndroidManifest.xml \
+        android/gradle/wrapper/gradle-wrapper.jar \
+        android/gradlew \
+        android/res/values/libs.xml \
+        android/build.gradle \
+        android/gradle/wrapper/gradle-wrapper.properties \
+        android/gradlew.bat \
+        android/AndroidManifest.xml \
+        android/gradle/wrapper/gradle-wrapper.jar \
+        android/gradlew \
+        android/res/values/libs.xml \
+        android/build.gradle \
+        android/gradle/wrapper/gradle-wrapper.properties \
+        android/gradlew.bat
+
+    ANDROID_PACKAGE_SOURCE_DIR = $$PWD/android
+}

examples/QZXingLive/android/AndroidManifest.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0"?>
 <manifest package="org.qtproject.example" xmlns:android="http://schemas.android.com/apk/res/android" android:versionName="1.0" android:versionCode="1" android:installLocation="auto">
     <application android:hardwareAccelerated="true" android:name="org.qtproject.qt5.android.bindings.QtApplication" android:label="QZXingLive" android:icon="@drawable/icon">
-        <activity android:configChanges="orientation|uiMode|screenLayout|screenSize|smallestScreenSize|layoutDirection|locale|fontScale|keyboard|keyboardHidden|navigation" android:name="org.qtproject.qt5.android.bindings.QtActivity" android:label="QZXingLive" android:screenOrientation="unspecified" android:launchMode="singleTop">
+        <activity android:configChanges="orientation|uiMode|screenLayout|screenSize|smallestScreenSize|layoutDirection|locale|fontScale|keyboard|keyboardHidden|navigation" android:name="org.ftylitak.qzxing.QZXingLiveActivity" android:label="QZXingLive" android:screenOrientation="unspecified" android:launchMode="singleTop">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>
                 <category android:name="android.intent.category.LAUNCHER"/>

examples/QZXingLive/android/build.gradle

@@ -4,7 +4,7 @@ buildscript {
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:1.1.0'
+        classpath 'com.android.tools.build:gradle:2.2.2'
     }
 }
 
@@ -18,6 +18,8 @@ apply plugin: 'com.android.application'
 
 dependencies {
     compile fileTree(dir: 'libs', include: ['*.jar'])
+    compile 'com.android.support:appcompat-v7:25.0.1'
+    compile 'com.android.support:design:25.0.1'
 }
 
 android {

examples/QZXingLive/android/gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Wed Apr 10 15:27:10 PDT 2013
+#Sun Jan 29 12:19:44 EET 2017
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.2.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-2.14.1-all.zip

examples/QZXingLive/android/src/org/ftylitak/qzxing/NativeFunctions.java

@@ -0,0 +1,6 @@
+package org.ftylitak.qzxing;
+
+public class NativeFunctions {
+    public static native void onPermissionsGranted();
+    public static native void onPermissionsDenied();
+}

examples/QZXingLive/android/src/org/ftylitak/qzxing/QZXingLiveActivity.java

@@ -0,0 +1,25 @@
+package org.ftylitak.qzxing;
+
+import android.Manifest;
+import android.content.pm.PackageManager;
+import org.qtproject.qt5.android.bindings.QtActivity;
+import static org.ftylitak.qzxing.Utilities.REQUEST_CAMERA;
+
+public class QZXingLiveActivity extends QtActivity {
+    @Override
+    public void onRequestPermissionsResult(int requestCode,
+                                           String permissions[], int[] grantResults) {
+        switch (requestCode) {
+            case REQUEST_CAMERA: {
+                // If request is cancelled, the result arrays are empty.
+                if (grantResults.length > 0
+                        && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
+                    NativeFunctions.onPermissionsGranted();
+                } else {
+                    NativeFunctions.onPermissionsDenied();
+                }
+                return;
+            }
+        }
+    }
+}

examples/QZXingLive/android/src/org/ftylitak/qzxing/Utilities.java

@@ -0,0 +1,42 @@
+package org.ftylitak.qzxing;
+
+import android.Manifest;
+import android.app.Activity;
+import android.content.pm.PackageManager;
+import android.support.v4.app.ActivityCompat;
+import android.support.v4.content.ContextCompat;
+
+import java.util.ArrayList;
+
+public class Utilities {
+
+    public static final int REQUEST_CAMERA = 0;
+
+    public static final String[] requiredPermissionsModifyPhoneState = {
+            Manifest.permission.CAMERA,
+            Manifest.permission.READ_EXTERNAL_STORAGE,
+            Manifest.permission.WRITE_EXTERNAL_STORAGE
+    };
+
+    public static void checkAndRequestPermissionList(Activity activity, String[] permissions) {
+        ArrayList<String> permissionsToRequest = new ArrayList<>();
+        for (int i = 0; i < permissions.length; i++) {
+            if (ContextCompat.checkSelfPermission(activity, permissions[i])
+                    != PackageManager.PERMISSION_GRANTED)
+                permissionsToRequest.add(permissions[i]);
+        }
+
+        if (permissionsToRequest.size() != 0)
+            ActivityCompat.requestPermissions(activity,
+                    permissionsToRequest.toArray(new String[0]),
+                    REQUEST_CAMERA);
+        else
+            NativeFunctions.onPermissionsGranted();
+    }
+
+    public static void requestQZXingPermissions(Activity activity) {
+        checkAndRequestPermissionList(activity, requiredPermissionsModifyPhoneState);
+    }
+
+
+}

examples/QZXingLive/application.cpp

@@ -0,0 +1,44 @@
+#include "application.h"
+#include <QDebug>
+#include "native.h"
+
+#if defined(Q_OS_ANDROID)
+    #include <QAndroidJniObject>
+    #include <QtAndroid>
+
+#endif // Q_OS_ANDROID
+
+Application::Application()
+{
+    //both signals will be connected to the same function for
+    //simplicity
+
+    connect(this, &Application::onPermissionsGranted,
+            this, &Application::initializeQML);
+
+    connect(this, &Application::onPermissionsDenied,
+            this, &Application::initializeQML);
+
+    NativeHelpers::registerApplicationInstance(this);
+}
+
+void Application::initializeQML()
+{
+    engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
+}
+
+void Application::checkPermissions()
+{
+#if defined(Q_OS_ANDROID)
+    //intentionally called in the C++ thread since it is blocking and will continue after the check
+    qDebug() << "About to request permissions";
+
+        QAndroidJniObject::callStaticMethod<void>("org/ftylitak/qzxing/Utilities",
+                                        "requestQZXingPermissions",
+                                        "(Landroid/app/Activity;)V",
+                                        QtAndroid::androidActivity().object());
+    qDebug() << "Permissions granted";
+#else
+    emit onPermissionsGranted();
+#endif //Q_OS_ANDROID
+}

examples/QZXingLive/application.h

@@ -0,0 +1,27 @@
+#ifndef APPLICATION_H
+#define APPLICATION_H
+
+#include <QQmlApplicationEngine>
+#include <QObject>
+
+class Application : public QObject
+{
+    Q_OBJECT
+
+public:
+    Application();
+
+    void checkPermissions();
+
+public slots:
+    void initializeQML();
+
+signals:
+    void onPermissionsGranted();
+    void onPermissionsDenied();
+
+private:
+    QQmlApplicationEngine engine;
+};
+
+#endif // APPLICATION_H

examples/QZXingLive/main.cpp

@@ -6,15 +6,17 @@
 
 #include <Qt>
 #include <QZXing.h>
+#include "application.h"
 
 int main(int argc, char *argv[])
 {
     QCoreApplication::setAttribute(Qt::AA_UseHighDpiPixmaps);
     QGuiApplication app(argc, argv);
-    QQmlApplicationEngine engine;
 
     QZXing::registerQMLTypes();
 
-    engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
+    Application customApp;
+    customApp.checkPermissions();
+
     return app.exec();
 }

examples/QZXingLive/native.cpp

@@ -0,0 +1,47 @@
+#include <jni.h>
+#include "native.h"
+#include <QMetaObject>
+
+QObject *NativeHelpers::application_p_ = 0;
+
+// define our native static functions
+// these are the functions that Java part will call directly from Android UI thread
+static void onPermissionsGranted(JNIEnv * /*env*/, jobject /*obj*/)
+{
+    QMetaObject::invokeMethod(NativeHelpers::getApplicationInstance(), "onPermissionsGranted"
+                              , Qt::QueuedConnection);
+}
+
+static void onPermissionsDenied(JNIEnv * /*env*/, jobject /*obj*/)
+{
+    QMetaObject::invokeMethod(NativeHelpers::getApplicationInstance(), "onPermissionsDenied"
+                              , Qt::QueuedConnection);
+}
+
+//create a vector with all our JNINativeMethod(s)
+static JNINativeMethod methods[] = {
+    {"onPermissionsGranted", "()V", (void *)onPermissionsGranted},
+    {"onPermissionsDenied", "()V", (void *)onPermissionsDenied},
+};
+
+// this method is called automatically by Java after the .so file is loaded
+JNIEXPORT jint JNI_OnLoad(JavaVM* vm, void* /*reserved*/)
+{
+    JNIEnv* env;
+    // get the JNIEnv pointer.
+    if (vm->GetEnv(reinterpret_cast<void**>(&env), JNI_VERSION_1_6) != JNI_OK)
+      return JNI_ERR;
+
+    // search for Java class which declares the native methods
+    jclass javaClass = env->FindClass("org/ftylitak/qzxing/NativeFunctions");
+    if (!javaClass)
+      return JNI_ERR;
+
+    // register our native methods
+    if (env->RegisterNatives(javaClass, methods,
+                          sizeof(methods) / sizeof(methods[0])) < 0) {
+      return JNI_ERR;
+    }
+
+    return JNI_VERSION_1_6;
+}

examples/QZXingLive/native.h

@@ -0,0 +1,20 @@
+#ifndef NATIVE_H
+#define NATIVE_H
+
+#include <QObject>
+
+class NativeHelpers {
+public:
+    static void registerApplicationInstance(QObject *app_p) {
+        application_p_ = app_p;
+    }
+
+    static QObject* getApplicationInstance() {
+        return application_p_;
+    }
+
+private:
+    static QObject *application_p_;
+};
+
+#endif // NATIVE_H