Develop Reference

Android Exclamatory red mark

I'm very new to Android. Whenever I create a new project using a new workspace, I get an exclamatory red mark in Eclipse in my project and an error at Appcompat. I searched here for an answer, but no answer was what I was looking for, so I just asked this. When I create a workspace at DDMS it displays this:
Sending Tracking request failed!
At Android, after I create a new project
WARNING: unable to write jarlist cache file here, src file, layout file not available.
I've searched a lot and found no solution.

OK, first thing first. Eclipse is no longer supported by Google. The only official IDE for Android Development is Android Studio Download Page.
Here is the announcement of Eclipse support ending
Over the past few years, our team has focused on improving the development experience for building Android apps with Android Studio. Since the launch of Android Studio, we have been impressed with the excitement and positive feedback. As the official Android IDE, Android Studio gives you access to a powerful and comprehensive suite of tools to evolve your app across Android platforms, whether it's on the phone, wrist, car or TV.
To that end and to focus all of our efforts on making Android Studio better and faster, we are ending development and official support for the Android Developer Tools (ADT) in Eclipse at the end of the year. This specifically includes the Eclipse ADT plugin and Android Ant build system.
Please note that the number of people using Eclipse to develop Android apps are going down. You will get less and less support even on Stackoverflow as time goes by. Overall, it is better to just make the switch while you are just starting.
Check on the first link, you will see some amazing documentation in the Android Studio IDE
If you 100% required to use Eclipse...
OK, so you have a job that requires Eclipse or there is some other reason, then check out this documentation by Eclipse.
Also, here is a list of all the different icons that can be displayed by Eclipse (credit for the icon list).
Build path problems are sometimes easy to miss among other problems in a project. The Package Explorer and Project Explorer views now show a new decorator on Java projects and working sets that contain build path errors:
The concrete errors can be seen in the Problems view, and if you open the view menu and select Group By > Java Problem Type, they all show up in the Build Path category:

Please refer this link too here
If you go to appcompat_v7/bin folder, you'll see that file "jarlist.cache" doesn´t appear or is unsynchronized. You need to
refresh the appcompat_v7 folder, only press F5 over that folder.
The appcompat_v7 folder is added because you use an action bar
component.
Aah. To avoid a new appcompat_v7_XX folder when you are creating a new
project, choose a LEVEL API 14 as Minimun Required SDK. After you must
modifier the AndroidManifest.xml and put the level that you need.
change it
android:targetSdkVersion="19" />
Delete all appcompat_v7_XX. It is a bug.
With appcompat_v7, You will see that Eclipse creates two XML files:
Activity_main.xml and fragment_main.xml. If you want to have an option
to create a project in the old way only with activity_main.xml, do
that:
Make a copy of the folder "BlanckActivity" located in this path:
\sdk\tools\templates\activities of an ADT previous version.
Rename the folder as “BlankActivityNoFragment”, then edit the field
name of the file "template.xml" with a notepad as
name=”BlankActivityNoFragment”
Copy the new folder in the same path of the new Eclipse
IDE:sdk/tools/templates/activities
Now you´ll see the new template when you go to create a new project.
Remember to choose as Minimum Required SDK an API 14

If you don't want the support of appcompat library then just remove it from your project by following steps :
Right click on project
Select properties
In dialog select android on left side
In dialog check library section
Remove appcompat library by selecting it and press remove
Extends your MainActivity.java with Activity
You can run your project successfully.
If you want the support of appcompat then follow this steps :
download the latest appcompat using Sdk Manager
import appcompat project in your eclipse
add it as a library project
extend your MainActivity with AppCompatActivity.

If you're getting any problem with app_compact library... This is the solution
Hopefully it will work....

According to the documentation
Decorates Java projects and working sets that contain build path
errors
There can be several reasons. Most of the times it may be some of the below reasons ,
You have deleted some of the .jar files from your /lib folder
You have added new .jar files
you have added new .jar files which may be conflict with others
So what to do is we have to resolve those missing / updating / newly_added jar files.
right click on the project and go to properties
Select Java Build Path
go to the Libraries tab
Remove the references of the jar files which you have removed already. There will be a red mark near them so you can identify them easily.
Add the references to the newly added .jar files by using Add JARs Refresh the project
This will solve the problem if it's because one of the above reasons.
Still Facing problem ??Try this:
Go to Windows -> Preferences -> Android -> Build and uncheck "Skip packaging and dexing until export or launch" then restart Eclipse.

Titanium Appcelerator Android module : How to create a proxy?

This is not a question but is an answer to the issues I was stuck up while creating custom Android module for Titanium appcelerator.
I was able to run the ExampleProxy provided by the framework but was having problems creating my own Proxy class.
I was able to access the proxy. After lot of search I got the reference of following question -
http://developer.appcelerator.com/question/153993/how-to-create-a-proxy#answer-264746
Following response partially works-
"Thank you very much Benjamin Bahrenburg for the clarification. Also i
thank Mads for your quick response.
Exact answer i was looking for : Need to remove the files in the bin,
libs, and build folder. Then do a clean, in Eclipse. After all of that
it tends to build. Please make sure you are using Ti 3.1.0 ( not 3.1.1
which has an issue)."
In addition on windows 7 machine I had following observations-
The Module-generated folder in C:\Users\username\AppData\Local\Temp\ must be deleted.
In the module folder delete following contents - entire contents of bin and libs and delete everything in build except \build\generated\Application.mk

It cost my 1 day to solve this problem.
to successfully create and run a ViewProxy, you have to:
change its file/class name (from ExampleProxy) to ViewProxy
clean the dirty files, including: build/, dist/, and some "lib.so " files in libs/ folder.
execute ti clean in your "Titanium app" folder.
your ViewProxy is not the same as the module name. e.g. your module name is: "GaodeMapModule", your proxy name should not be: "GaodeMapProxy", it doesn't work.

Android - Adding JAR File to eclipse (hotpotato API)

I'm having this problem, and tried googling and doing tutorials in eclipse. But, it wasnt really helpful for me to use this .jar file in my project.
Source: https://github.com/brunodecarvalho/hotpotato
To be specific, I downloaded this jar file , added it to my project successfully by copying the jar file into my source folder , then added it by doing(Properties->Add Jars->And added it). Also i did a Project -> Clean.
Then once I start coding as they have shown in the examples, it gives me errors, which proves that the Adding of Jar file was not successful.
I tried in different eclipse workspaces but still no luck.
If I explain what I'm trying to do here, I'm working on a Android Download Manager Project. What I need to do is to create a pipeling connection to the request URL so that I can download the packets parallel.
Please help me find my mistake. Thanks for your time!

You can try the following:
Remove the jar from the buildpath - and make a folder called libs underneath the root of the project, at the same level as src / bin / etc.
Then put your lib in there, build path issues may then arise if you are in Eclipse but i believe everything should auto resolve from there.
In the past I have put the jar in the libs folder and additionally added it to the build path from there.
Does it error in the IDE, or at runtime?

Not all Java libraries are compatible with Android. Do what RenegadeAndy wrote here, and if that doesn't work, the lib might really be incompatible with Android.
Remember, Android is not a real Java implementation.

Missing AndroidManifest.xml when importing an old Android project into Eclipse

I have an Android project developed on Eclipse (GNU/Linux) that I last touched half a year ago. I am trying to import the project into Eclipse 3.6 on Windows (with ADT installed) installed using File -> Import Project in Eclipse. When the project is imported, I see the following error twice on the console:
[2010-12-10 02:17:12 -
com.android.ide.eclipse.adt.internal.project.AndroidManifestHelper]
Unable to read C:\Program
Files\Android\android-sdk-windows\AndroidManifest.xml:
java.io.FileNotFoundException:
C:\Program
Files\Android\android-sdk-windows\AndroidManifest.xml
(The system cannot find the file
specified)
Why is Eclipse looking for AndroidManifest.xml on the Android SDK path? The file actually seems to be in the project's directory. How do I fix this problem and get the project to compile?

A simple solution is to either reimport the AndroidManifest.xml file or make a change to the file and save it. This worked for me.

If you see an error about AndroidManifest.xml, or some problems
related to an Android zip file, right click on the project and select
Android Tools > Fix Project Properties. (The project is looking in the
wrong location for the library file, this will fix it for you.)
from: http://developer.android.com/resources/tutorials/notepad/notepad-ex1.html

The way you are importing the Android project into Eclipse is wrong. The Correct way of doing is File -> New Android Project. In the Contents Tab in "New Android Project", select "Create project from existing source" and choose the Build Target. That should fix your problem.

It appears that this error is produced because Eclipse thinks the default location for new Android projects is the Android SDK path. Even if the project location is changed, the error fails to be resolved, so the trick is to change the project location before Eclipse is aware of the condition generating the error.
To circumvent this quirk I imported the old project with the following steps:
File -> New -> Android Project
Un-check 'Use default location' and browse to project root directory.
Click 'Create project from existing source'
It's important to do step (2) before (3) otherwise the error persists and prevents running the project.

I had the same problem, all of the above did not work. I cleaned the project and it worked.

Instead of using File ---> New Android Project --> "Create project from existing sources", which will result in the error your are seeing, choose "Create project from existing sample" and choose it from the drop down. This will work.
Experienced JAVA developers tend to go with the first option which is normally there and works for classic Eclipse projects. But this is not your typical project and I bet the Google developers put this special case in the wizard to accommodate the differences.

I had the same problem. I was trying to compile the JakeWharton view page sample, so I checked out the GIT in a directory in a different folder then the workspace which caused the problem.
Eclipse was maintaining 2 folders:
1. A new workspace folder was made under the workspace directory, which eclipse checks for libraries and others source code including the AndroidManifest.xml file
2. The existing folder which was not under the Root workspace
To fix the problem after importing I had to manually move the files in the new workspace folder created by eclipse.

I met this problem when using Facebook SDK, now I solve it by doing this:
Close the project;
Copy "AndroidManifest.xml" file to the project's root path;
Open the project and refresh it, it's Done!

this worked for me by the way:
I changed the project name to the exact name of the project that I am importing.

Eclipse seems somewhat fragile in its naming conventions. One of the causes for this error is a difference between the project name and the folder name in the workspace. I imported a zip file for a project named "HelloDialogs" into a workspace folder named "HelloDialog". This caused the "AndroidManifest.xml file missing" error. Once I renamed the folder correctly, everything worked fine.

Because of the multiple different answers here, I thouhgt I'd add yet another one that worked for me, as I had exactly the same issue when first working with Phonegap android dev tools.
So I found (as mentioned by Gintautas in comments to the accepted answer), that I had to create a new project using the phonegap 'create' script, then when importing the project into eclipse. the only way to get this to work successfully was if the project was originally created in some temp folder somewhere other than the place I actually want to work with it.
So I created a project in windows like this in a cmd window...
c:\phonegap\phonegap-2.6.0\lib\android\bin>create.bat c:\temp\android_boilerplates\test app.test test
Then I imported the project in eclipse like this...
File > New > Project
Within the new project wizard select: "Android Project from Existing Code"
Click "Next"
Now navigate to the temp location of your project and set that to the root directory, check the project you want and check "Copy projects into workspace" as the example below...
Click "Finish"
And that's it, Eclipse should copy all your project files into your workspace and there shouldn't be any errors in your project (fingers crossed).
Your project should look something like this...
Hope that helps, it took me an age to work out why Eclipse didn't like creating a new project from existing code when the new project was being setup in the same place as the existing code. This isn't a problem for other languages I've used, so it was a little weird, but understandable as Eclipse (I'm guessing) seems to want to overwrite certain files.

Eclipse randomly decided to make another folder instead of the one that i had specified, but doesnt have any resources or data or layout etc in it..
it has some conflicts i guess..
anyway, a noob approach to this was, copying the original file to some other location(i put it to desktop)..
now create new project-create existing project, select this one from desktop, n VOILA.. its all fine.. :D

I am a little late to this game but I caused this same problem by generating the initial application into the exact location I was going to work on it. That is to say I put it directly into my current workspace. I then did File, Import, Existing Android Code Into Workspace. The import process blanked out my android.xml file.
I tried above solutions and had no joy. I then generated the initial application into a temp directory and imported from there. This worked for me.

The only way to import a project into eclipse workspace is to create an empty project and then drag and drop all the folders and files into this project. Why is this so is beyond me.
The answer from Raunak is wrong.

I found a .classpath file in the root directory of my Android project. I opened it and updated the file paths in it, and it seemed to fix the problem for me.

I had the problem when I tried to update an old project with recent code from the SVN. I had the Manifest.xml exported to my local file system as backup and deleted it. I've then reverted my complete project to the most recent version from the SVN and then it worked :)

This is what I had to do to get this to work. Fortunately I had backups of earlier "project".
1) Import the project as usual.
2) If the errors with empty xml etc. comes up, close the project.
3) Go to the original project if you have backup.
4) Copy all of the projects root files and directories and paste it over where Eclipse expects the projects root directories and files to be.
5) Open the project and refresh. Make "Clean" if necessary and you're done!
Always make backups because Eclipse f--kups! I learned this the hard way when suddenly my Android project refused to work because of empty manifest-file.

Sometimes if you automatically fix imports in MainActivity IDE imports android.R class instead of one that will be generated for the project. Remove the import and recompile.

when importing project from another workspace add existing project in workspace. and tick to the copy projects in workspace.then check the api level and supporting library from project.properties files.then rebuilt project and clean it.. it is works for me.

2017 Solution: Much Easier and tested solution is to remove your application folder from elipse project only then Import it again and the problem will be fixed immediately!

How to find easily the source of an android class

I know I can access android source code from https://android.googlesource.com, but it's hard to select the right git repo if I only know the package and the name of an android class.
Isn't there a way to locate a file in https://android.googlesource.com?

Most things you'll want to see can be found under the frameworks/base repo.
This includes pretty much all the public and private API classes that make up the Android Java framework.
If you want to be able to browse the source from within Eclipse, you can follow this guide: http://blog.michael-forster.de/2008/12/view-android-source-code-in-eclipse.html
Finally, the Android SDK Reference Search extension for Chrome lets you browse the public API by typing ad into the URL bar, and it adds a convenient "view source" link to each Javadoc page.

In my opinion today the best way to look into android sources is the github repository :
https://github.com/android/
Public java classes can be found here https://github.com/android/platform_frameworks_base/tree/master/core/java/android
Internal package is here https://github.com/android/platform_frameworks_base/tree/master/core/java/com/android/internal
Resources are here https://github.com/android/platform_frameworks_base/tree/master/core/res/res
Support library https://github.com/android/platform_frameworks_support

Since 2011 the source code can be downloaded with the SDK Manager (Window > Android SDK Manager)
Install package "Sources for Android SDK"
Open Properties of android.jar, which you can find in the package explorer below the Android library
In "Java Source Attachment", select android/sdk/sources as external folder
Edit: Eclipse seems to regularly scan the external folder for updates. If this annoys you, you can zip the folder into a .jar and then tell Eclipse to look in that jar for the sources. Eclipse will then no longer scan for changes.

There is an issue raised against Android project for a single .jar file containing the Java sources.
The issue has been declined but the comments are a good source of methods to access the source in Eclipse.

also, this is a very good tutorial on how to get the source in eclipse, without having to mess with any of the repos or anything, it includes zip files of the the source (which might be out of date)

You can search for any Android class through https://cs.android.com easily.