Develop Reference

Xamarin Android MobileBarcodeScanner.Initialize(Application) not found

Help,
I am using Xamarin.Android And I already install Zxing.Net.Mobile 2.4.1
Why i cant using MobileBarcodeScanner.Initialize(Application)
is there any component i have to install?
See this SS

So for those who land here later, The short answer is there's an error in the ZXing.Net.Mobile project Readme. The call to ZXing.Mobile.MobileBarcodeScanner.Initialize(Application) should go in the main activity class for the Android project, in the OnCreate method, not in the method that instantiates the scanner object. It should follow the call to ZXing.Net.Mobile.Forms.Android.Platform.Init(). Otherwise you will get the object reference error.
As a side note, I think you'll want to ensure that both ZXing.Net.Mobile and ZXing.Net.Mobile.Forms packages are installed across all your Xamarin projects. Also, version 2.4.1 appears to be based on .NET Standard, whereas the earlier versions appear to be based on .NET Framework. I found this out when I tried to downgrade as suggested in an earlier comment.

You can use Zxing.Net.Mobile 2.3.1, I test it, it did not have this issue.

Mono.Zeroconf NuGet package will not install in Xamarin

I am using Xamarin 6.3 on a mac. I am very new to Xamarin.
I have a project open. I choose "Project" -> "Add NeGet Projects..."
I type "Mono" in the search box, and check the box next for Mono.Zeroconf, then choose "Add Package"
There are several lines of output, but the last line is:
Could not install package 'Mono.Zeroconf 0.9.0'. You are trying to install this package into a project that targets 'MonoAndroid,Version=v4.4', but the package does not contain any assembly references or content files that are compatible with that framework. For more information, contact the package author.
I have tried changing the version of my android package, but each one results in failure.
Thanks in advance for any assistance

This project doesn't support Xamarin.Android as it only contains libraries for desktop .NET 2.0. This library would need to support the MonoAndroid target or a PCL/dotnet standard target.
Sadly this library hasn't been updated since 2011 it looks like! Thus it is very unlikely it will support Xamarin.Android unless it's updated in the future.
Source:
https://github.com/mono/Mono.Zeroconf

Using selective APIs from Google Play Services in Eclipse

In my project I am integrating push notification for that I require classes from com.google.android.gms package.
Is it possible for me to include selected package from whole library?
I am using eclipse. actually there are lot more libraries required, due to which I am facing 65k multidex issue. Any solution?

If you really really want to use the Eclipse to compile this, you need to perform these steps:
Have someone with Android studio include your needed Google components as dependency.
Kidnap the components from exploded-aar Android studio folder and setup the components as your own Eclipse library.
But of course, this is highly not a recommended procedure, but this is for those people who desperately needs it as last resort. This also marks a disclaimer that the kidnapped libraries are already free from the developer's accountability, because you didn't compile it the right way.
PS. Did this with Google Maps

If you want to use selective components of the Google Play Services you will need to switch to Android studio.
Read this: (Source)
Important: Support for the Android Developer Tools (ADT) in Eclipse
has ended, per our announcement. You should migrate your app
development projects to Android Studio as soon as possible. For more
information on transitioning to Android Studio, see Migrating from
Eclipse ADT.
If you still want to continue using eclipse, you'll have to to the hard work yourself - of deleting the unwanted packages/components from the full source code and making sure it compiles and works fine.
Instructions of setting up selective APIs can be found on this page, for android studio. For Eclipse, as the documentation says nothing about setting up selective APIs, you just have to go with the whole set.

NO. you have to migrate your code to Android Studio.

How to fix titanium ERROR: Asset package include titanium.jar not found

Well, I have configured the emulator, the paths in the studio, everything seems to be ok, but i can't make it works.

Not sure if this is still an issue but certain version of titanium does not support Android build tools above a certain version like explained here:
https://developer.appcelerator.com/question/178514/
So you could check this and check if your titanium is up to date.

Opening android AOSP native applications in eclipse

I need to edit the original Android Apps from packages
in terms make my own distro/mod..
I want to make changes to the In Call screen, lock screen, contacts, calendar etc..
I understand that for doing this I will have to build everything from
source,
however I need to edit the source and to do so I need to open the OS provided apps as
eclipse projects,
When I did I saw that there are
missing imports which are hidden in the SDK (or missing)
hidden parameters within the classes..
I don't want to use reflection since the whole code is here and
available, but how do you build a platform development kit..
or PDK ?:)
Can any one help?

You start by reading the documentation.
EDIT:
If you are trying to download some single project from AOSP and compile it using the SDK, odds are very strong that it will not work, and that you will encounter problems like the ones you cite. You do not build Android by building individual apps; you build Android ("my own distro/mod") by building the entire firmware. Most AOSP applications are not designed to be compiled by the SDK, but need the whole firmware.

Please check Using eclipse to browse and edit AOSP. You can atleast edit your code using eclipse, but you will have to use AOSP build system to build your distro.
You might also check Debugging Android Java Framework services as that would help debug your changes.

Just open Eclipse,
then go to "window" +"preferences" +"android"
there you will get sdk location,then give the appropriate path of the android sdk for proper run...