R.Java is not generated

Question

I downloaded the code from google codes , but when I import this project into my eclipse environment it does not generate the R.Java file. I searched a lot of blogs and forums and tried a lot of things like cleaning, rebuilding, creating a project from an existing source, etc., but still encountering a problem. Some people mentioned that this is sometimes caused by SVN client software, but none of them mentioned any solution for this. I will be very grateful to you guys if you download it yourself and find out what the problem is.

Answer 1

In general, for it to work:

• import the project into eclipse (File → Import → General → Existing projects in the workspace)
• in Eclipse, manually create the gen folder and add it as the source folder (right-click on your project, "Build Path" → "Configure Build Path" → "Add Folder").
• Clean your project, suppose you created R.java

But this is not so, why?

Because there is some compilation error (or an error?) Regarding the xml file in res, so R is not genetared (I tested on my Mac):
In res / values ​​/styles.xml: the following is commented:

<style name="iWindowTitleBackground" parent="android:WindowTitleBackground"> <item name="android:background">@drawable/title_bar</item> </style> 

In res / values ​​/themes.xml: comment on the following:

 <item name="android:windowTitleBackgroundStyle">@style/iWindowTitleBackground</item> 

Then do Project -> Clean, you should get R.java.

It is reported that parent = "android: WindowTitleBackground" cannot be enabled on some operating systems, see here for more details.

Answer 2

Whenever a generated R-class is not generated, it indicates a problem with its creation due to some parsing problem from XML resources. Check the error console in your IDE to find out what exactly is wrong.

Common problems:

• Unescaped character in strings.xml e.g. you're instead of you\'re
• Missing layout_width or layout_height in layout resources
• Invalid namespace declarations
• Variable names that are not supported by Java, for example, due to capitalization or the use of spaces, hyphens, or other unsupported characters
• Any other syntax error in XML
• Check the Console for problems (the image is attached where the console identifies the problem, why R is not generating in your project).

Answer 3

When I encounter this problem, I delete the gen folder and it will be recreated with all r files

Answer 4

you will see at the top of your file that says import android.r or r.java, I forgot. you need to delete this line, clear the project and repeat.
Basically, android uses R to refer to elements of your project. but when this import statement is there, it overrides the browsing of your project directories and uses androids

Answer 5

I ran into the same problem trying to build the wiktionary example code that I downloaded from code.google.com ( here ) I imported into a new Eclipse Juno project designed to use Android 4.1 and JDK 1.6.

Here is an excerpt from the console after creating the project:

W / ResourceType (6292): Bad XML block: header size 103 or total size 0 greater than data size 0 C: \ Development \ WorkJava \ android \ sampleapps \ Wiktionary \ com.example.android.wiktionary.LookupActivity \ res \ values \ Strings.xml: 23: error: several substitutions specified in non-positional format; did you want to add the formatted = "false" attribute? C: \ Development \ WorkJava \ android \ sampleapps \ Wiktionary \ com.example.android.wiktionary.LookupActivity \ res \ values ​​\ strings.xml: 23: error: Unexpected end tag string

Here is an excerpt from res / values ​​/string.xml:

 <resources> <string name="app_name">Wiktionary Word of the Day</string> <string name="app_descrip">A fast Wiktionary browser and Word-of-day widget</string> <string name="app_credits">"All dictionary content provided by Wiktionary under a GFDL license. http://en.wiktionary.org\n\nIcon derived from Tango Desktop Project under a public domain license. http://tango.freedesktop.org".</string> <string name="template_user_agent">"%s/%s (Linux; Android)"</string> <string name="template_wotd_title">"Wiktionary:Word of the day/%s %s"</string> <string name="template_wotd_archive_title">"Wiktionary:Word_of_the_day/Archive/%s/%s"</string> 

Decision

Adding formatted = "false" to the last 3 line definitions (containing two% s placeholder substitutions), as shown below, solved the problem. Project recovery created R.java in the gen folder.

 <resources> <string name="app_name">Wiktionary Word of the Day</string> <string name="app_descrip">A fast Wiktionary browser and Word-of-day widget</string> <string name="app_credits">"All dictionary content provided by Wiktionary under a GFDL license. http://en.wiktionary.org\n\nIcon derived from Tango Desktop Project under a public domain license. http://tango.freedesktop.org".</string> <string name="template_user_agent" formatted="false">"%s/%s (Linux; Android)"</string> <string name="template_wotd_title" formatted="false">"Wiktionary:Word of the day/%s %s"</string> <string name="template_wotd_archive_title" formatted="false">"Wiktionary:Word_of_the_day/Archive/%s/%s"</string> 

Answer 6

I still had this error after verifying that all my resources did not have errors, cleanup, restore, reboot, etc.

I fixed this by filtering out SVN files from the project.

How to exclude .svn directories from search in Eclipse?

While the question mentions the search, the solution relates to which files are used during compilation.

Rebooted and everything is in order.

Answer 7

". xml files" and "image files" and make sure the names are lowercase.

Answer 8

Change the workspace to a new directory and set its permissions so that it is accessible to everyone

Answer 9

In my case, I found the name of the image file containing the uppercase inside res / drawable. after changing the image name. it was resolved and I could build a project

Answer 10

I have encountered this problem many times. The rule of thumb is to check your .xml files.
R.java is not generated if there is any problem in the .xml file.

Answer 11

Just click

 Build --> Clean Project 

It worked for me