how to install oracle jdk 7 manually on ubuntu

http://www.printandweb.ca/2012/04/manually-install-oracle-jdk-6-for.html

how to uninstall jdk on ubuntu perfectly

sudo apt-get purge oracle-java7-installer

How to fix freeze problem in Ubuntu 10.04

http://digitalspine.blogspot.com/2010/11/ubuntu-lucid-1004-freezeslock-ups.html

how to display multiple lines of text on a button

In layout xml file, add the following.




for example, android:text="Hi
Hello"







In coding,  just use '\n'.

how to solve problem that java file is opened in gedit, not java editor in eclipse.

Right click on the file on the package manager, and go to  "open with" menu. Choose default editor, not system editor.

how to solve javahl error in Ubuntu

I installed sublicpse and got javahl error whenever I started eclipse. The following is how to solve that error.


1. type "sudo apt-get install libsvn-java" in the terminal.



2. Type "gedit ~/.eclipse/eclipserc" in the terminal and add the line VMARGS="-Djava.library.path=/usr/lib/jni" on the file, and save it.



3. add this line to your eclipse.ini

-Djava.library.path=/usr/lib/jni

how to fix "NoClassDefFoundError"

check if the folder name where jar library file is located is "libs", not "lib". if the folder name is "lib", then change the name to "libs". Then it will work, and the error will be gone.