In short, use the PackageManager class to get the PackageInfo : PackageInfo pkgInfo = getPackageManager().getP... To build an APK, make these changes to the greetings app : Change the layout to ( res/layout/main.xml ): <?xml version="1.0" encoding="utf-8"?> <LinearL... Change the string values ( res/values/strings.xml ): <?xml version="1.0" encoding="utf-8"?> <resourc... Update AndroidManifest.xml : <?xml version="1.0" encoding="utf-8"?> <manifes... Create a new Java class src/com/android/appinfo/GetAppVersion.java : package com.android.appinfo; import android... Edit build.xml , change project name to "AppInfo": <?xml version="1.0" encoding="UTF-8"?> <project... Install to emulator: ant install Screenshot:

Use show create table <tablename> : mysql> show create table my_test_table; +------... Select from information_schema.table_constraints and information_schema.key_column_usage mysql> select * from information_schema.table_cons...

The bash environment variable PROMPT_COMMAND contains a regular bash command that is executed just before the command prompt is displayed. For example: $ export PROMPT_COMMAND=a bash: a: command not ... The command a is not valid so you get the error message every time you hit enter. Echo something before $PS1 : $ export PROMPT_COMMAND='echo -n Hi!' Hi!$ ... PROMPT_COMMAND is regularly used to change the xterm window title. You may find this in /etc/bashrc : case $TERM in xterm*) if [ -...

This example uses an Intent with Uri scheme tel: to invoke the phone dialer. Create a new project with: $ ~/android-sdk-linux_86/tools/android create proj... Update the layout res/layout/main.xml to add a text field and a button: <?xml version="1.0" encoding="utf-8"?> <LinearL... Update the Java class src/com/android/intenttest/CallPhone.java to handle button click and start the built-in phone dialer with Intent : package com.android.intenttest; import andr... Update AndroidManifest.xml to add CALL_PHONE permission: <?xml version="1.0" encoding="utf-8"?> <manifes... Install to the emulator and test: ant install The phone dialer will be invoked when you click the "Call" button. So how did this happen? The CallPhone activity creates an Intent with action Intent.ACTION_CALL and Uri tel:<a number> and sends it off to Android. Android starts the activity com.android.phone.OutgoingCallBroadcaster because the intent matches the...

The String.format() method provides versatile formatting capabilities. This tutorial tries to present these capabilities in a accessible manner. The format string A format string can contain zero, one, or more format specifiers . The general form of a format specifier is: %[argument_index$] [flags] [width] [.precision]co... where things in square brackets are optional, and conversion is a character indicating the conversion to be applied to the corresponding variable value. The only required characters in the format specifier is the percent sign % and the conversion character. A simple example: public static void simpleFormat() { System.out... The Argument index The argument index is specified by a number, terminated by the dollar sign $ . The same argument may be repeated multiple times in a format string. Unindexed...

When you run a Java application, the default place it looks for trusted certificates is $JAVA_HOME/jre/lib/security/cacerts , which is a keystore that contains a list of trusted CA certificates. You can use the keytool to list the certificates: C:\>keytool -list -keystore C:\jdk1.6.0_20\jre\lib... Simply hit return when asked for password, no password is required to list trusted certificates in a keystore.

An XML schema is a definition of XML files, in XML. It plays the same role as old-time DTDs. Overall, an XML schema file looks like this: <schema attributeFormDefault = (qualified | u... The attribute meanings: targetNamespace : The name space targeted by the current schema definition. It can be any URI. id and version : For user convenience, the W3C spec defines no semantics for them. xml:lang : Natural language identifier defined by RFC 3306 . attributeFormDefault and elementFormDefault : Set default values for the form attribute for attribute and element declarations. blockDefault and finalDefault : Set default values for the block and final attributes for attribute and element declarations. The W3C defined some built-in datatypes . Examples of primitive datatypes are: string ,...

The PHP function array_unique removes duplicate values from arrays. It takes an optional parameter $sort_flags , which can be one of: SORT_REGULAR : compare items normally (don't change types) SORT_NUMERIC : compare items numerically SORT_STRING : compare items as strings SORT_LOCALE_STRING : compare items as strings, based on the current locale. Example: <?php $a = array( '1' => 'Apple', ... Output: array_unique results: array(3) { [1]=> ...

The PHP function isset determines if a variable is assigned a value. It returns TRUE if a variable is set and not NULL . Example: <?php $a = "not empty"; $b = ''; // t... A nice little function to assign a default value if a value is not given: <?php function isset_or(&$check, $alternate = N...

To sign an Android APK from command line: Sign the APK with jarsigner (using default keystore, android-root is the alias of the signing key): $ jarsigner -signedjar HelloWorld-new.apk HelloWor... Verify signature (optional) $ jarsigner -verify -verbose -certs HelloWorld-new... Align the APK (must use -v 4 option): $ ~/android-sdk-linux_86/tools/zipalign -v 4 Hello...