I need to know how to implement a barcode reader. Had implemented a previously but update the version of the project for Silverlight 8.1 (previously used version 8). Does anyone have an example?
I'm looking for several tutorials on how to read barcode (scan) for windows phone, but yet have not found one that supports version 8.1 SILVERLIGHT
The app is live on the Windows Store and has a 8.0 version. If I re-target to Windows Phone 8.1 and publish with new features, will it be available for Windows Phone 8.0 users?
Most of our users are still on 8.0.
The user (OS/Store) downloads the most suitable package of the app. If user has WP8.1 and your app has a 8.1 package, then this will be installed, otherwise 8.0 app package will be downloaded.
From what you have written, you already have a working WP8.0 version of the app, now if you want to add some new features from 8.1 then, once you retarget the app, you have to add new package to your app when you are updating it. Do not replace the old working 8.0 package. Once you have added new package and it has passed certification, all users that have 8.0 version of your app and 8.1 OS version, will be prompted that there is an update available.
What is important:
you can retarget to both 8.1 Silverlight and Runtime (of course the second option needs some more changes and some things to be rewritten),
IsolatedStorage is preserved,
when you retarget to Runtime, you will have to parse IsoalatedStorageSettings from file in LocalStorage.
I've done similar thing with WP8.0 -> WP8.1 Runtime, I also recommend to test it on beta app, so you will be sure how it works.
If you re-target the app to Windows Phone 8.1, it'll be available to only Windows Phone 8.1 users. If you submit such an app to Store, it'll be displayed only in devices running Windows Phone 8.1.
However, you can submit two packages for same app in Windows Phone Store. So while submitting an update for your app, instead of replacing the existing Windows Phone 8.0 package, you can add another package for the Windows Phone 8.1 version which will have new features. The Windows Phone Store will ensure that it shows the correct XAP to correct OS version. This way, Windows Phone 8.1 users will be able take advantage of the new features, while Windows Phone 8.0 users will still be able to access the old app.
Going forward, if you want to support both OS versions, I'll suggest to keep a copy of Windows Phone 8.0 project before re-targeting to Windows Phone 8.1.
Yes, if you just re-target the project! But make sure you aren't using native WP 8.1 features, as they wouldn't work on WP8.
How can i use that? In Windows Phone 8.1 project there is no System.Data namespace. In internet I could not found any documentation for SQLite to Windows Phone 8.1
You need to install SQLite extension. http://visualstudiogallery.msdn.microsoft.com/5d97faf6-39e3-4048-a0bc-adde2af75d1b
This tutorial might help too.
I have Sqlite install on my system with visual studio 2012 ultimate.Now,I don't have knowledge to how it can be use with windows phone app for saving data and retrieving data from database?
Here are some posts to get you started:
A New SQLite Wrapper for Windows Phone 8 and Windows 8 – The Basics
SQLite with a bit of MVVM Light in Windows Phone 8
Using the SQLite database engine with Windows Phone 8 apps
Windows Phone 8 SQLite cross platform sample
Some great SQLite for Windows Phone posts
Using a simple ORM with sqlite on WP7
The short story is: I have my laptop that has a processor without Virtualization and Second Level Adress Translation capabilities that are required for running the new Windows Phone 8 SDK.
I can however use the windows phone 7.1 sdk, but for testing my apps i will use a windows phone 8 device.
Is it possible to deploy and test my apps on the connected WP8 device, altough i am using the 7.1 SDK that predates the WP8 os?
I don't think it's possible to deploy apps using WP7.1 SDK on WP8 devices, however, you can install the Visual Studio 2012 + Windows Phone 8 SDK (if you have Windows 8 x64) even when you don't have SLAT enabled CPU. The Windows Phone 8 SDK will work, only you won't be able to launch the WP8 emulator.
No you cannot, The .xap packing mechanism in Windows phone 7.1 and 8 are different so you cannot deploy this xap using deployment tool. But, if we are using windows 8 + wp8 dev tools you can debug the application that developed on 7.1. In future after the launch of wp 7.8 ms may provide a solution for this. for now there is no other alternative is available in front of you