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Displaying keyword search results 21 - 30
Created by alfa on May 26, 2011 13:23:30    Last update: May 26, 2011 13:23:30
The operator instanceof returns true if the first operand is an instance of the second operand: if (a instanceof A) { // true if a is an in... If the above is true, then this is also true: A.class.isAssignableFrom(a.getClass()); The only difference is, the second operand to instanceof is the symbol for a class, not a class object: // This is OK if (a instanceof A) { Syst...
Created by freyo on May 17, 2011 11:13:17    Last update: May 17, 2011 11:13:17
This is an odd-ball content provider in that it doesn't provide database records, but provides a resource as a stream. It can be used to provide media files or XML resources. Start the project with: tools/android create project --package com.android... Create assets directory and add an XML file ( assets/demo.xml ): <? xml version="1.0" encoding="UTF-8"?> <people... Edit the layout ( res/layout/main.xml ): <?xml version="1.0" encoding="utf-8"?> <LinearL... Edit src/com/android/cptest/Dummy.java : package com.android.cptest; import java.io.... Add content provider ( src/com/android/cptest/XmlResource.java ): package com.android.cptest; import java.io.... Update AndroidManifest.xml : <?xml version="1.0" encoding="utf-8"?> <manifes... Add this section to the end of build.xml : <target name="-package-resources"> <ech... Build and install: ant install Screenshot: Remove the Dummy activity ( AndroidManifest.xml ): <?xml version="1.0" encoding="utf-8"?> <manifes... Create a new project for...
Created by jinx on May 03, 2011 11:43:26    Last update: May 03, 2011 11:43:26
The PHP function strval returns the string value of a variable. It does the same thing as casting a variable to string, or automatic conversion where string is expected. Conversion rules: Type String Value Boolean TRUE '1' Boolean FALSE '' (empty string) integer of float string representing the number Array The string 'Array' Object Result of __toString() if defined, error otherwise Resource 'Resource id #n' , where n is a number assigned to the resource. NULL '' (empty string) Example: <?php set_error_handler(function($errno, $errst... Results: bool(true) --------------------- strval: '1'...
Created by jinx on April 29, 2011 15:03:10    Last update: April 29, 2011 15:04:02
The PHP function is_callable verifies that a variable can be invoked as a function. Example: <?php define('F', 'f'); function... Output: var_dump: string(1) "f" is_callable: 1 Calla...
Created by jinx on April 28, 2011 20:52:45    Last update: April 29, 2011 13:27:31
This is normally a syntax error just before some variable. Try some of these: Missing operator before a variable: <?php $a = 'ab'; echo('Missing conca... Missing semicolon at end of line: <?php echo('Missing semicolon at end of lin... Missing ( and ) in for loop: <?php foreach $a as $i { echo "$i\n"; ... Missing keyword before class variable: <?php class A { // should be var $a; ...
Created by jinx on April 26, 2011 21:52:10    Last update: April 26, 2011 21:52:10
PHP offers several ways to check the class type of an object instance at runtime: instanceof operator, is_a function, get_class function. Example: <?php class A { } class B { } ...
Created by jinx on April 25, 2011 12:43:40    Last update: April 25, 2011 12:43:40
Use the PHP function method_exists to check if the class or object has a certain method. It returns TRUE if the method exists (even when the value of the property is NULL), FALSE if the method does not exist. Example: <?php class A { var $p = 'A property'; ... Outputs: Class A has method f1: bool(true) Object $a has... Also note that C++-like method overloading does not exist in PHP. Thus there's no ambiguity about which version of the method exists, i.e., with no argument, with one argument... etc. The following code generates Fatal error: <?php class A { var $p = 'A property'; ...
Created by jinx on April 25, 2011 11:50:09    Last update: April 25, 2011 11:51:53
Use the PHP function property_exists to check if the class or object has a certain property. It returns TRUE if the property exists (even when the value of the property is NULL), FALSE if the property does not exist, or NULL in case of an error. Example: <?php class A { var $p = 'A property'; ... Outputs: Class A has property $p: bool(false) Class A ha...
Created by freyo on April 18, 2011 15:08:21    Last update: April 18, 2011 15:12:20
Generate android project $ ~/android-sdk-linux_86/tools/android create proj... Create XML file res/xml/books.xml : <?xml version="1.0"?> <catalog> <book id=... Edit layout ( res/layout/main.xml ): <?xml version="1.0" encoding="utf-8"?> <Lin... Edit code ( src/com/android/xmlres/XMLResource.java ): package com.android.xmlres; import java.io.... Change activity label from app_name to booklist ( AndroidManifest.xml ): <?xml version="1.0" encoding="utf-8"?> <manifes... Add value for string resource ( res/values/string.xml ): <?xml version="1.0" encoding="utf-8"?> <resourc... Deploy and test: ant install
Created by alfa on April 08, 2011 12:33:08    Last update: April 08, 2011 12:33:08
This example captures the screen of the current Java application window, instead of the full screen. import java.io.*; import java.awt.*; import ...
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