/*! * Ext JS Library 3.4.0 * Copyright(c) 2006-2011 Sencha Inc. * licensing@sencha.com * 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;