Arun P Johny's Blog

Adding and Removing Options from Select box

Arun P Johny — Sat, 04 Apr 2009 13:44:09 +0000

Adding options to a select element in html using dynamic javascript

function addOption(selectbox, value, text){
   var optn = new Option();
   optn.text = text;
   optn.value = value;
   selectbox.options.add(optn);
}

We can add new options to a select element using the options array present in the select object. We can create a new option using the new operator and Option class provided by javascript or by using document.createElement(“OPTION”);

Removing all options from a select box

function removeAllOptions(selectbox){
   if(selectbox && selectbox.options && selectbox.options.length > 0){
   while(selectbox.options.length > 0){
   selectbox.remove(0);
   }
   }
}

To remove a option from select element we can use the remove method in the select object. It takes the index of the option to be removed as an argument.

Here is a sample html snippet which uses select element and addition and removal of options using javascript

   Select Box 1:

Enable GC dumb in JVM

Arun P Johny — Thu, 12 Mar 2009 03:28:31 +0000

-verbose:gc — prints basic information about GC to the standard output
-XX:+PrintGCTimeStamps — prints the times that GC executes
-XX:+PrintGCDetails — prints statistics about different regions of memory in the JVM
-Xloggc: — logs the results of GC in the given file

Enable Jconsole In Tomcat

Arun P Johny — Thu, 12 Mar 2009 03:22:54 +0000

Add the following properties to JVM settings

-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.authenticate=false
-Dcom.sun.management.jmxremote.port=
-Dcom.sun.management.jmxremote

can be anything like 5000

Retaining scroll position after store load

Arun P Johny — Mon, 23 Feb 2009 02:55:29 +0000

view config:
onLoad: Ext.emptyFn,
listeners: {
beforerefresh: function(v) {
v.scrollTop = v.scroller.dom.scrollTop;
},
refresh: function(v) {
v.scroller.dom.scrollTop = v.scrollTop;
},

}