This is a two-part question about adding a third-party library (JAR) to an Android project in Eclipse.
The first part of the question is, when I try to add a third-party JAR (library) to my Android project I first get the problem of
Error parsing XML: unbound prefix
because I'm trying to use a class from that JAR (and need the prefix somehow defined). What's going on?
Second, (after fixing that--the answer is given below), my application doesn't work on Android and I discover via the debugger (LogCat) that the class I'm attempting to consume doesn't exist.
Caused by:
java.lang.ClassNotFoundException:
com.github.droidfu.widgets.WebImageView...
Why, when I get no compilation or linker error in Eclipse, does it have this problem on the emulator?
These two questions are rhetorical for I'm going to answer them myself below. Other posts in this forum creep up to the problem and elsewhere there is discussion, but I feel that I can be more explicitly helpful for the next guy to come along.
Now for the missing class problem.
I'm an Eclipse Java EE developer and have been in the habit for many years of adding third-party libraries via the "User Library" mechanism in Build Path. Of course, there are at least 3 ways to add a third-party library, the one I use is the most elegant, in my humble opinion.
This will not work, however, for Android, whose Dalvik "JVM" cannot handle an ordinary Java-compiled class, but must have it converted to a special format. This does not happen when you add a library in the way I'm wont to do it.
Instead, follow the (widely available) instructions for importing the third-party library, then adding it using Build Path (which makes it known to Eclipse for compilation purposes). Here is the step-by-step:
Download the library to your host
development system.
Create a new folder, libs, in
your Eclipse/Android project.
Right-click libs and choose
Import -> General -> File System,
then Next, Browse in the filesystem
to find the library's parent
directory (i.e.: where you
downloaded it to).
Click OK, then click the
directory name (not the checkbox) in
the left pane, then check the
relevant JAR in the right pane. This
puts the library into your project
(physically).
Right-click on your project,
choose Build Path -> Configure Build
Path, then click the Libraries tab,
then Add JARs..., navigate to your
new JAR in the libs directory and
add it. (This, incidentally, is the moment at which your new JAR is converted for use on Android.)
NOTE
Step 5 may not be needed, if the lib is already included in your build path. Just ensure that its existence first before adding it.
What you've done here accomplishes two things:
Includes a Dalvik-converted JAR
in your Android project.
Makes Java definitions available
to Eclipse in order to find the
third-party classes when developing (that is, compiling)
your project's source code.
Ensure that your 3rd party jars are in your projects "libs" folder and they will be put in the .apk when you package your application. You may see runtime errors on the device if something in the jar is not supported, but other than that I have had great success with this.
Setting up a Library Project
A library project is a standard Android project, so you can create a new one in the same way as you would a new application project.
When you are creating the library project, you can select any application name, package, and set other fields as needed, as shown in figure 1.
Next, set the project's properties to indicate that it is a library project:
In the Package Explorer, right-click the library project and select Properties.
In the Properties window, select the "Android" properties group at left and locate the Library properties at right.
Select the "is Library" checkbox and click Apply.
Click OK to close the Properties window.
The new project is now marked as a library project. You can begin moving source code and resources into it, as described in the sections below.
If you are using the ADT version 22, you need to check the android dependencies and android private libraries in the order&Export tab in the project build path
First, the problem of the missing prefix.
If you consume something in your layout file that comes from a third party, you may need to consume its prefix as well, something like "droidfu:" which occurs in several places in the XML construct below:
<com.github.droidfu.widgets.WebImageView android:id="#+id/webimage"
android:layout_width="75dip"
android:layout_height="75dip"
android:background="#CCC"
droidfu:autoLoad="true"
droidfu:imageUrl="http://www.android.com/images/opensourceprojec.gif"
droidfu:progressDrawable="..."
/>
This comes out of the JAR, but you'll also need to add the new "xmlns:droidfu"
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:droidfu="http://github.com/droidfu/schema"
...>
or you get the unbound prefix error. For me, this was a failure to copy and paste all of the supplied example from the third-party library's pages.
Error parsing XML: unbound prefix
Resource '/playteddy/res' does not exist.
I got the above two errors and finally I solved it.
Right click your project -> properties -> java build path -> googleadmobadsdk (select and put it top), then you run and problem solved. It is solved my runtime error.
Put the source in a folder outside yourt workspace.
Rightclick in the project-explorer, and select "Import..."
Import the project in your workspace as an Android project.
Try to build it, and make sure it is marked as a library project.
Also make sure it is build with Google API support, if not you will get compile errors.
Then, in right click on your main project in the project explorer.
Select properties, then select Android on the left.
In the library section below, click "Add"..
The mapview-balloons library should now be available to add to your project..
Go to build path in eclipse, then click order and export, then check the library/jar, and then click the up button to move it to the top of the list to compile it first.
Related
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.
I can’t link Android projects in Eclipse.
I get a VerifyError, and some can’t find class warnings, which I assume means that it’s not getting the library.
I’m using project properties > Java Build Path > Projects.
I can get it to work by referencing the other projects jar. Then setting the source attach so that I can step through the code, but this is a much uglier way of setting the projects up because linking to source and linking to the jar doesn’t allow the use of path variables. So the next person to pick up this project is going to be really confused when the project doesn’t work for them.
Is it possible to directly link projects?
Is it possible to use path variables to reference jars and source
attachments?
It’s so easy to do in Flash Builder…
Also, when I change anything in properties > Android then hit okay, when I open properties > Android the changes have been reverted, what's that about?
If you are asking if an android project can reference a "library" project, the answer is yes; open the properties for the main android project and select Android menu and then at the bottom half of the screen, you can Add your library project to your main project. Note that the "library" project should be set as a library project (same UI allows you to set a project as library)
HTH,
Ali.
assuming you're talking about a library project that you have in your eclipse workspace.
go to properties -> Android
on the bottom half of the screen you should see a "Library" pane.
click add and point it to your library that's in your workspace that you want to add.
click apply afterwards.
i'd remove what you added in that library pane that you're talking about. that's for jar libraries that you've added to your project's libs folder.
I'm trying to get ActionBarSherlock and the ViewPagerIndicator libraries set up for my projects, but I seem to be running into a few issues. I sent Jake Wharton (The developer) a few messages earlier about it, and got a few replies but couldn't get anywhere - and I think he got busy with a few other things.
What my issue is, For both VPI and ABS
Both libraries open up without any errors, and I'm using compiler version 1.6 for all as is required.
The funny thing is, if I load in the samples that are provided - they work fine and link to his library; but when I go to add the library to my project - the above happens.
Where to store the actual library project does not matter, as long as you use a relative link to reference it. Check out the Library Projects - Development considerations:
Library project storage location
There are no specific requirements on where you should store a library project, relative to a dependent application project, as long as the application project can reference the library project by a relative link. What is important is that the main project can reference the library project through a relative link.
You should always use the Eclipse ADT plugin to select and set up Library Project Reference, i.e. right-click project -> Properties -> Android -> Add, then in the opened Project Selection window, select the Library Project list here (of cause you should import them in the same Eclipse workspace as your Main Project). This will add a android.library.reference using relative path into project.properties as well as show relative path in the Android preference window:
android.library.reference.2=../../../../../Documents and Settings/yorkw/Desktop/JakeWharton-Android-ViewPagerIndicator-f09acb0/library
If you directly alter it using absolute path from project.properties as below:
android.library.reference.1=C:\\Documents and Settings\\yorkw\\Desktop\\JakeWharton-Android-ViewPagerIndicator-f09acb0\\library
Then after Eclipse refresh your project, you get the exact error described in your question, see my screenshot below:
Hope this helps.
While importing the libraries, make sure that you tick the "Copy projects int workspace" check box. The library projects need to be in the same workspace for them to work.
delete and import the project and lib again. build the lib project , add lib to project, still error shows.. rename the lib project. this worked for me ....
I followed some steps I found here (can't find the URL right now, sorry) to convert my Android project in Eclipse to a layout where 99.9% of my code is in a library project, and then I have 2 other shell projects under the same workspace that are mostly just the AndroidManifest.xml files, and a few resource files. This was done so I can support 2 builds of the same project, with just some minor text/icon changes between the 2. The application name is also different so I can publish both on the Android Market at the same time.
Ever since I did this, about every 10 times I compile, maybe once every day or two, I get "dalvik error 1" and something about "Access already exists" (Access being the name of the first Java unit in my library project).
To "work around" the issue I go in to the Java Build path for my stub-project that I am trying to build, and remove the JAR file from my main library from the libraries tab. Then I can build without the error.
Then a while later (maybe 1 or 2 days) I'll get an error about missing classes when I compile my stub-project (not my library). So I'll go back to the Java Build path and put the reference to the JAR file back in, and all is good again for 1 or 2 days, then I'm back to the same error as before.
Is this just a known issue and something I need to do, or can I resolve by a restructure of my projects/workspaces? Currently I have:
Lib Project - only has 2 libs on build path: Android 2.1 and com.android.ide.eclipse.adt.LIBRARIES
First stub project that uses above lib - has the same 2 libs as above project, plus sometimes I use "Add JAR" to include the JAR from the above project's bin\ folder.
2nd stub project - same libs as first stub project
Should I reference the JAR from my "lib project" using one of the other tabs under build path options? Maybe the "Project" tab instead, or the "Source" tab? I don't currently have it under any of those other areas.
When I get in to the weird state, doing a "Clean project" also doesn't help, I've tried that several times and open/close the IDE between cleaning, to no resolve.
At this point we are in the final testing stages, so my normal daily task is:
Make a minor update (bug fix) in the LIB project
Use the publish wizard to export both projects and update Android Market and other places we keep the APK files
So I'd like those steps to stay simple, without having to open/close multiple workspaces or go through a lot of build steps if possible.
The classical Eclipse/Java way
Add a (workspace) library
Right click the project you want to insert in.
Click Properties.
Select Java Build Path.
Select the Libraries tab.
Now, it depends how you compile your library.
So either do an Add JARs... or an Add Class Folder.
Choose the external variant to use an external source.
That's it.
Add a workspace project
Right click the project you want to insert in.
Click Properties.
Select Java Build Path.
Select the Projects tab.
Click Add... on the right side and you are done.
The additional Android way
Two steps are necessary:
Mark the project you want to use as library project
Reference the marked project
Mark the library project
Right click your project and select Properties.
Select Android on the left and tick the checkbox IsLibrary. Done.
Reference the marked project
Right click your project and select Properties.
Select Android on the left and Add... your marked project. It will be added to the list and is ready to use. Now you are able to access all classes and ressources (e.g. drawables, strings) from the referenced, marked project. Awesome, eh? :)
As I was writing up this question I managed to solve it so repeat it here for the benefit of others. Here is the initial problem:
I have created a very simple library project which I want to reference in another project. I have done this previously with no problems so not really sure why it is not working this time. I have:
Flagged the library project via project properties. The default.properties file has this set : android.library=true
In my other project added reference to my library project via project properties. The default.properties file has the reference added as expected ie android.library.reference.1=K:/android_test_ws/applicationRegistrar
The green tick against the referenced library project starts off green and then changes to a red cross.
This implies that there must be something wrong / missing from the library project but I don't know what. My library project on this occasion is MUCH simpler than the previous one I created.
OK Here is the solution which I found when I was looking for the default.properies file of the referencing project (not the library) in my file system. Although the referencing project was in the same eclipse workspace as the library project, the actual files were somewhere else in the file system ie they were'nt in the same parent folder of the library project. As soon as I placed the referencing project in the same physical folder as the library project it all went fine.
I guess that this must be something to do with android using ant underneath the covers.
Edit: The project name needs match the folder name on the file system. What you are seeing in the Project Properties->Android->Library Reference is a relative file system path.
Make Sure both the projects are present in same work space.
To Do it, while importing the projects make sure "copy project into work space" check box is checked.
the same problem will occur if your library project is in different partition from your current workspace. I have the same problem just now. My git source is in C: and I just move my workspace to D: and everything start to collapse.
Simplest way to get the library paths paths correct is to use the GUI from Eclipse to add the library as shown in the following screenshot and let Eclipse take care of putting the correct relative paths in project.properties. Its a common setup to have your library projects hosted at directories vastly different than your main projects that uses the library. This method will work if the "libary project" and the project using it are in the same eclipse "workspace" (they "need not" be in same parent folder):
Please ensure that the library project is marked as "Is Library" - right click on the library project - properties - Android - mark the "Is Library" checkbox - in project.properties of the library project you should have a new entry:"android.library=true. Now add it into the project you want as described in the post below.(the post with image integrated - from Nilesh Pawar).
This bug is referenced several times here 27199, 35786, 36460 & 38052
Maybe by voting for them, it will be fixed one day...
Yet another observation on the same issue.
For me the two projects where on the same parent folder, and were both local inside the workspace. Even then the issue was still happening.
The I edited the "project.properties" file and put the absolute path(with forward slashes '/' for seperator) of the library project. Saved and closed it. Then went to the project properties dialog, removed the library(which was still showing the cross icon but with abs path) and added it back as usual.
Surprisingly the issue is resolved, and the project compiles and runs.
This is really strange and must be a bug with the ADT.
I am using ADT version 20.0.2
when developer referencing the facebook or any other library project then first of all clean the project from eclipse->project->clean project.
that want allow the error of red cross in referencing screen.
For me, I just restart the eclipse and the added library works fine.
I mean first time it showing red marks after adding the library project.
Though eclipse main project and library project are in same workspace folder and no resources files are in outside of the project folder.
So, you can try with to restart your eclipse. Happy coding....
Workaround for me was to
Create a new workspace
Import Library Project in that workspace
Import The desired project in that workspace
Having both project and library project the same target Android OS version
Reference library project in my project
solved my problem
i had the same problem there when i try to change my workspace so this my solution:
import and copy all project data including library project into workspace
delete the old project reference by Right-click on the project-->Properties-->Android-->Library, and select corrupted library(so that waht i call it) and choose Remove
clean project first (to refresh ur project properties)
go to library project Properties-->Android-->Library and check the is library if it does'nt click Apply then OK
if the library project is library is already checked, first Unchecked it then Clean the library project after that do the Step 4 again
go to project that u want the library are in then Right-click on the project-->Properties-->Android-->Library, Add then choose the library project (it should be there) and click Apply then OK
if still doesn't appear clean the project once more time and that should do
Just restart your eclipse. It's solve my problem
When you have a look at the reference-path before and after, it comes from i.e. "C:/workspace/mylib" and goes to "../../mylib" when copied to the correct location, quite interesting.
FYI,
What worked for me was to delete the 'library' projects (the actual projects) from my workspace (without deleting the files), and then re-importing them using the wizard (import existing android project from source code).
Thanks for posting the question.
I had exactly the same problem while integrating Facebook with my Android application. I fixed the issue by moving my development project to the same Windows drive in which library project was located. Somehow Eclipse is unable to read the library project's location properly from default.properties file if it is in a different drive.
Similar to Sufi Khan's post I also solved this issue with a reboot. My case differed in that when I first accessed Properties->Android and added the library I got a lovely green checkmark. When I closed the dialog Eclipse was still showing class-not-found type errors. When I checked the properties again I saw the red X. But Mr. Kahn's solution (delete the bad lib, restart Eclipse, add the lib again) worked fine.
I'm using the 0702 version of the ADT bundle (starts with "cluster", rhymes with "duck").
I followed the accepted answer but also had to make sure my "project.properties" file was readable.
If the file is readonly (checked into source control) eclipse will not edit it. Adding the library reference will succeed, but the change won't be persisted after hitting OK.
If closing the preferences window and reopening in again removes the library you just added, this may be your solution.
In case your library project still doesn't show up try adding library flag in your library project properties
Add android.library=true
project.properties
# This file is automatically generated by Android Tools.
# Do not modify this file -- YOUR CHANGES WILL BE ERASED!
#
# This file must be checked in Version Control Systems.
#
# To customize properties used by the Ant build system edit
# "ant.properties", and override values to adapt the script to your
# project structure.
#
# To enable ProGuard to shrink and obfuscate your code, uncomment this (available properties: sdk.dir, user.home):
#proguard.config=${sdk.dir}/tools/proguard/proguard-android.txt:proguard-project.txt
# Project target.
target=android-17
android.library=true