/*!
* Ext JS Library 3.3.1
* Copyright(c) 2006-2010 Sencha Inc.
* [email protected]
* http://www.sencha.com/license
*/
/**
* @class Ext.util.Functions
* @singleton
*/
Ext.util.Functions = {
/**
* Creates an interceptor function. The passed function is called before the original one. If it returns false,
* the original one is not called. The resulting function returns the results of the original function.
* The passed function is called with the parameters of the original function. Example usage:
*
var sayHi = function(name){
alert('Hi, ' + name);
}
sayHi('Fred'); // alerts "Hi, Fred"
// create a new function that validates input without
// directly modifying the original function:
var sayHiToFriend = Ext.createInterceptor(sayHi, function(name){
return name == 'Brian';
});
sayHiToFriend('Fred'); // no alert
sayHiToFriend('Brian'); // alerts "Hi, Brian"
* @param {Function} origFn The original function.
* @param {Function} newFn The function to call before the original
* @param {Object} scope (optional) The scope (this reference) in which the passed function is executed.
* If omitted, defaults to the scope in which the original function is called or the browser window.
* @return {Function} The new function
*/
createInterceptor: function(origFn, newFn, scope) {
var method = origFn;
if (!Ext.isFunction(newFn)) {
return origFn;
}
else {
return function() {
var me = this,
args = arguments;
newFn.target = me;
newFn.method = origFn;
return (newFn.apply(scope || me || window, args) !== false) ?
origFn.apply(me || window, args) :
null;
};
}
},
/**
* Creates a delegate (callback) that sets the scope to obj.
* Call directly on any function. Example: Ext.createDelegate(this.myFunction, this, [arg1, arg2])
* Will create a function that is automatically scoped to obj so that the this variable inside the
* callback points to obj. Example usage:
*
var sayHi = function(name){
// Note this use of "this.text" here. This function expects to
// execute within a scope that contains a text property. In this
// example, the "this" variable is pointing to the btn object that
// was passed in createDelegate below.
alert('Hi, ' + name + '. You clicked the "' + this.text + '" button.');
}
var btn = new Ext.Button({
text: 'Say Hi',
renderTo: Ext.getBody()
});
// This callback will execute in the scope of the
// button instance. Clicking the button alerts
// "Hi, Fred. You clicked the "Say Hi" button."
btn.on('click', Ext.createDelegate(sayHi, btn, ['Fred']));
* @param {Function} fn The function to delegate.
* @param {Object} scope (optional) The scope (this reference) in which the function is executed.
* If omitted, defaults to the browser window.
* @param {Array} args (optional) Overrides arguments for the call. (Defaults to the arguments passed by the caller)
* @param {Boolean/Number} appendArgs (optional) if True args are appended to call args instead of overriding,
* if a number the args are inserted at the specified position
* @return {Function} The new function
*/
createDelegate: function(fn, obj, args, appendArgs) {
if (!Ext.isFunction(fn)) {
return fn;
}
return function() {
var callArgs = args || arguments;
if (appendArgs === true) {
callArgs = Array.prototype.slice.call(arguments, 0);
callArgs = callArgs.concat(args);
}
else if (Ext.isNumber(appendArgs)) {
callArgs = Array.prototype.slice.call(arguments, 0);
// copy arguments first
var applyArgs = [appendArgs, 0].concat(args);
// create method call params
Array.prototype.splice.apply(callArgs, applyArgs);
// splice them in
}
return fn.apply(obj || window, callArgs);
};
},
/**
* Calls this function after the number of millseconds specified, optionally in a specific scope. Example usage:
*
var sayHi = function(name){
alert('Hi, ' + name);
}
// executes immediately:
sayHi('Fred');
// executes after 2 seconds:
Ext.defer(sayHi, 2000, this, ['Fred']);
// this syntax is sometimes useful for deferring
// execution of an anonymous function:
Ext.defer(function(){
alert('Anonymous');
}, 100);
* @param {Function} fn The function to defer.
* @param {Number} millis The number of milliseconds for the setTimeout call (if less than or equal to 0 the function is executed immediately)
* @param {Object} scope (optional) The scope (this reference) in which the function is executed.
* If omitted, defaults to the browser window.
* @param {Array} args (optional) Overrides arguments for the call. (Defaults to the arguments passed by the caller)
* @param {Boolean/Number} appendArgs (optional) if True args are appended to call args instead of overriding,
* if a number the args are inserted at the specified position
* @return {Number} The timeout id that can be used with clearTimeout
*/
defer: function(fn, millis, obj, args, appendArgs) {
fn = Ext.util.Functions.createDelegate(fn, obj, args, appendArgs);
if (millis > 0) {
return setTimeout(fn, millis);
}
fn();
return 0;
},
/**
* Create a combined function call sequence of the original function + the passed function.
* The resulting function returns the results of the original function.
* The passed fcn is called with the parameters of the original function. Example usage:
*
var sayHi = function(name){
alert('Hi, ' + name);
}
sayHi('Fred'); // alerts "Hi, Fred"
var sayGoodbye = Ext.createSequence(sayHi, function(name){
alert('Bye, ' + name);
});
sayGoodbye('Fred'); // both alerts show
* @param {Function} origFn The original function.
* @param {Function} newFn The function to sequence
* @param {Object} scope (optional) The scope (this reference) in which the passed function is executed.
* If omitted, defaults to the scope in which the original function is called or the browser window.
* @return {Function} The new function
*/
createSequence: function(origFn, newFn, scope) {
if (!Ext.isFunction(newFn)) {
return origFn;
}
else {
return function() {
var retval = origFn.apply(this || window, arguments);
newFn.apply(scope || this || window, arguments);
return retval;
};
}
}
};
/**
* Shorthand for {@link Ext.util.Functions#defer}
* @param {Function} fn The function to defer.
* @param {Number} millis The number of milliseconds for the setTimeout call (if less than or equal to 0 the function is executed immediately)
* @param {Object} scope (optional) The scope (this reference) in which the function is executed.
* If omitted, defaults to the browser window.
* @param {Array} args (optional) Overrides arguments for the call. (Defaults to the arguments passed by the caller)
* @param {Boolean/Number} appendArgs (optional) if True args are appended to call args instead of overriding,
* if a number the args are inserted at the specified position
* @return {Number} The timeout id that can be used with clearTimeout
* @member Ext
* @method defer
*/
Ext.defer = Ext.util.Functions.defer;
/**
* Shorthand for {@link Ext.util.Functions#createInterceptor}
* @param {Function} origFn The original function.
* @param {Function} newFn The function to call before the original
* @param {Object} scope (optional) The scope (this reference) in which the passed function is executed.
* If omitted, defaults to the scope in which the original function is called or the browser window.
* @return {Function} The new function
* @member Ext
* @method defer
*/
Ext.createInterceptor = Ext.util.Functions.createInterceptor;
/**
* Shorthand for {@link Ext.util.Functions#createSequence}
* @param {Function} origFn The original function.
* @param {Function} newFn The function to sequence
* @param {Object} scope (optional) The scope (this reference) in which the passed function is executed.
* If omitted, defaults to the scope in which the original function is called or the browser window.
* @return {Function} The new function
* @member Ext
* @method defer
*/
Ext.createSequence = Ext.util.Functions.createSequence;
/**
* Shorthand for {@link Ext.util.Functions#createDelegate}
* @param {Function} fn The function to delegate.
* @param {Object} scope (optional) The scope (this reference) in which the function is executed.
* If omitted, defaults to the browser window.
* @param {Array} args (optional) Overrides arguments for the call. (Defaults to the arguments passed by the caller)
* @param {Boolean/Number} appendArgs (optional) if True args are appended to call args instead of overriding,
* if a number the args are inserted at the specified position
* @return {Function} The new function
* @member Ext
* @method defer
*/
Ext.createDelegate = Ext.util.Functions.createDelegate;