Develop Reference

How to get Sqlite.net extensions working?

I'm struggling to use Sqlite.net Extensions in my Xamarin Android app.
I get the exeption:
Don't know about System.Collections.Generic.List`1 [app_name.Model.modelName]
The problem is similar to:
Sqlite extension is not working as expected
and
Use SQLiteNetextensions with Xamarin for Android-App
but the answers from there are not working for me and I can't add comments, so I have to start a new question.
I was trying to install different sqlite.net extensions packages and got no result.
Using SQLite.Net Extensions-PCL 2.0.0-alpha2 gives me such exeption:
System.IO.FileNotFoundException: Could not load assembly 'SQLite.Net, Version=3.0.5.0, Culture=neutral, PublicKeyToken='. Perhaps it doesn't exist in the Mono for Android profile?
I'm using Sql-net library:
https://www.nuget.org/packages/sqlite-net-pcl/
Does anyone has a final solution to this problem, please?
Edit:
I had to create a new project and paste everything in from the old one.
I don't think that answers the issue, but it's enough for me...

I'm using Sql-net library:
https://www.nuget.org/packages/sqlite-net-pcl/
The link here you give is the right lib, but you really installing this package? Cause you also said that you're installing SQLite.Net Extensions-PCL 2.0.0-alpha2.
Please try to install the package in the following screenshot, the latest stable version is 1.3.3:

I can't find Java_org_opencv_objdetect_CascadeClassifier for opencv android sdk in jni folder?

Have all of source code been release? My opencv version is 2.4.9. I have reorganize my project,write
Android.mk by myself.Finally I run face-detection demo and I got "Native method not found: org.opencv.objdetect.CascadeClassifier.CascadeClassifier_1:" something like this. I have search the whole opencv source but I can't find Java_org_opencv_objdetect_CascadeClassifier_CascadeClassifier_1 or anything like this.

I dont know the specific question by you.But Native method not found is the common error.Possible reasons for native method not found are
1.)the type mismatch in the c++ function name and java function name.The c++ function name must be in
the format Java_PackageName_classname_functionname
2.)you are calling function before initilization of opencv library.
If you are again not able to find please share your code

the sample problem puzzled me long time.
(my apk running well as using Android studio install it,when using Android.mk to complie in Android System (put source file to packages/apps/"apk name"))
I just replay"libopencv_java3.so"file by "\OpenCV-android-sdk\sdk\native\libs\arm64-v8a\libopencv_java3.so",because this two files size is different,then this problem is solved.
as a result , this problem should be caused by "libopencv_java3.so"

Missing CvViewFrameListener2 interface

I'm new to Android and OpenCV, and I try to follow this simple tutorial. I got stuck at implementation of CvViewFrameListener2 interface:
Defines that your activity implements CvViewFrameListener2 interface and fix activity related errors by defining missed methods.
Eclipse shows an error, that the CvFrameListener2 cannot be resolved to a type. It seems like this interface doesn't exist in the library.
I load OpenCV4Android version 2.4.5. Can anybody help me?

I m sure this is late. But I faced this problem too, here my workaround
make sure you have imported the openCV sdk as a library project and linked to your project.
Hope this help
also I used this project from github for face recognition face recognition
and this link to download OpenCV 2.4.6 android sdk
http://sourceforge.net/projects/opencvlibrary/files/opencv-android/2.4.6/OpenCV-2.4.6-android-sdk-r2.zip/download

Errors when adding Rajawali Framework to project

I planned to test the OpenGL framework Rajawali.
When I follow the tutorial on how to set it up I do the following:
Create an Android project.
Import the Rajawali source code. As soon as that is done I get the error:
"The method setOffsetNotificationsEnabled(boolean) is undefined for the type WallpaperService.Engine Wallpaper.java /Rajawali-master/src/rajawali/wallpaper line 312".
and
"The method setOffsetNotificationsEnabled(boolean) of type Wallpaper.WallpaperEngine must override or implement a supertype method Wallpaper.java /Rajawali-master/src/rajawali/wallpaper line 310".
When I try to link the Rajawali project with the project I created I get errors:
The container 'Android Dependencies' references non existing library "D:\Prosjekter\Rajawij\Rajawali-master\bin\rajawali-master.jar".
and
"The project cannot be built until build path errors are resolved". <--- Should go away as soon as the other errors are fixed I guess.
Anyone have experience with Rajawali or have an idea on how I get solve the problems?
Thanks for any help!

I've been using Rajawali extensively for a few months. I would ensure you have all Google APIs installed up to 4.2+ Also be sure to grab the most current Master branch from their github. The links on the tutorial pages are out of date. https://github.com/MasDennis/Rajawali
They moved away from using a compiled JAR and instead are encouraging linking it as a library to your project. When you do that be sure to clean all projects and make sure that you don't have any files or folders in your project that are duplicates of those in Rajawalis libs folder.
Good luck, its a fantastic framework.

Stacktrace for C on Android

I have C code in my Android app and would like to catch crashes and print them to a log file. I saw this post, and tried, but I can't find the execinfo lib.
I'm working with Ubuntu 11.10 and using NDK for compiling to Android.
Does anyone know how to find execinfo lib for NDK/ARM, or have another simple solution?

On Android, you have some sample specials utils code allowing to see and/or dump the stack.
Implementation is in base/libs/utils/CallStack.cpp. You'll a find a tiny sample code here.