Fix sd card permission

android/AndroidManifest.xml

@@ -102,5 +102,6 @@
 
     <uses-permission android:name="android.permission.INTERNET"/>
     <uses-permission android:name="android.permission.WRITE_INTERNAL_STORAGE"/>
+    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
     <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
 </manifest>

android/src/AndroidInterface.cc

@@ -12,10 +12,25 @@
 #include "QGCApplication.h"
 #include "AndroidInterface.h"
 #include <QAndroidJniObject>
+#include <QtAndroid>
 
 QString AndroidInterface::getSDCardPath()
 {
     QAndroidJniObject value = QAndroidJniObject::callStaticObjectMethod("org/mavlink/qgroundcontrol/QGCActivity", "getSDCardPath",
                             "()Ljava/lang/String;");
-    return value.toString();
+    QString sdCardPath = value.toString();
+
+    QString readPermission("android.permission.READ_EXTERNAL_STORAGE");
+    QString writePermission("android.permission.WRITE_EXTERNAL_STORAGE");
+
+    if (QtAndroid::checkPermission(readPermission) == QtAndroid::PermissionResult::Denied ||
+            QtAndroid::checkPermission(writePermission) == QtAndroid::PermissionResult::Denied) {
+        QtAndroid::PermissionResultMap resultHash = QtAndroid::requestPermissionsSync(QStringList({ readPermission, writePermission }));
+        if (resultHash[readPermission] == QtAndroid::PermissionResult::Denied ||
+                resultHash[writePermission] == QtAndroid::PermissionResult::Denied) {
+            return QString();
+        }
+    }
+
+    return sdCardPath;
 }