Extjs 随笔备忘


//Point1. 

Ext.define 是用来创建类的。可以用来创建一个自定义的类,在这个自定义类中,可以用extend来继承Ext中的组件类。

举例:

Ext.define('Ext.ux.LiveSearchGridPanel', {
    extend: 'Ext.grid.Panel',
    requires: [
        'Ext.toolbar.TextItem',
        'Ext.form.field.Checkbox',
        'Ext.form.field.Text',
        'Ext.ux.statusbar.StatusBar'
    ],
    
    /**
     * @private
     * search value initialization
     */
    searchValue: null,
    
    /**
     * @private
     * The row indexes where matching strings are found. (used by previous and next buttons)
     */
    indexes: [],
    
    /**
     * @private
     * The row index of the first search, it could change if next or previous buttons are used.
     */
    currentIndex: null,
    
    /**
     * @private
     * The generated regular expression used for searching.
     */
    searchRegExp: null,
    
    /**
     * @private
     * Case sensitive mode.
     */
    caseSensitive: false,
    
    /**
     * @private
     * Regular expression mode.
     */
    regExpMode: false,
    
    /**
     * @cfg {String} matchCls
     * The matched string css classe.
     */
    matchCls: 'x-livesearch-match',
    
    defaultStatusText: 'Nothing Found',
    
    // Component initialization override: adds the top and bottom toolbars and setup headers renderer.
    initComponent: function() {
        var me = this;
        me.tbar = ['Search',{
                 xtype: 'textfield',
                 name: 'searchField',
                 hideLabel: true,
                 width: 200,
                 listeners: {
                     change: {
                         fn: me.onTextFieldChange,
                         scope: this,
                         buffer: 100
                     }
                 }
            }, {
                xtype: 'button',
                text: '<',
                tooltip: 'Find Previous Row',
                handler: me.onPreviousClick,
                scope: me
            },{
                xtype: 'button',
                text: '>',
                tooltip: 'Find Next Row',
                handler: me.onNextClick,
                scope: me
            }, '-', {
                xtype: 'checkbox',
                hideLabel: true,
                margin: '0 0 0 4px',
                handler: me.regExpToggle,
                scope: me                
            }, 'Regular expression', {
                xtype: 'checkbox',
                hideLabel: true,
                margin: '0 0 0 4px',
                handler: me.caseSensitiveToggle,
                scope: me
            }, 'Case sensitive'];

        me.bbar = Ext.create('Ext.ux.StatusBar', {
            defaultText: me.defaultStatusText,
            name: 'searchStatusBar'
        });
        
        me.callParent(arguments);
    },
    
    // afterRender override: it adds textfield and statusbar reference and start monitoring keydown events in textfield input 
    afterRender: function() {
        var me = this;
        me.callParent(arguments);
        me.textField = me.down('textfield[name=searchField]');
        me.statusBar = me.down('statusbar[name=searchStatusBar]');
    },
    // detects html tag
    tagsRe: /<[^>]*>/gm,
    
    // DEL ASCII code
    tagsProtect: '\x0f',
    
    // detects regexp reserved word
    regExpProtect: /\\|\/|\+|\\|\.|\[|\]|\{|\}|\?|\$|\*|\^|\|/gm,
    
    /**
     * In normal mode it returns the value with protected regexp characters.
     * In regular expression mode it returns the raw value except if the regexp is invalid.
     * @return {String} The value to process or null if the textfield value is blank or invalid.
     * @private
     */
    getSearchValue: function() {
        var me = this,
            value = me.textField.getValue();
            
        if (value === '') {
            return null;
        }
        if (!me.regExpMode) {
            value = value.replace(me.regExpProtect, function(m) {
                return '\\' + m;
            });
        } else {
            try {
                new RegExp(value);
            } catch (error) {
                me.statusBar.setStatus({
                    text: error.message,
                    iconCls: 'x-status-error'
                });
                return null;
            }
            // this is stupid
            if (value === '^' || value === '$') {
                return null;
            }
        }

        return value;
    },
    
    /**
     * Finds all strings that matches the searched value in each grid cells.
     * @private
     */
     onTextFieldChange: function() {
         var me = this,
             count = 0;

         me.view.refresh();
         // reset the statusbar
         me.statusBar.setStatus({
             text: me.defaultStatusText,
             iconCls: ''
         });

         me.searchValue = me.getSearchValue();
         me.indexes = [];
         me.currentIndex = null;

         if (me.searchValue !== null) {
             me.searchRegExp = new RegExp(me.searchValue, 'g' + (me.caseSensitive ? '' : 'i'));
             
             
             me.store.each(function(record, idx) {
                 var td = Ext.fly(me.view.getNode(idx)).down('td'),
                     cell, matches, cellHTML;
                 while(td) {
                     cell = td.down('.x-grid-cell-inner');
                     matches = cell.dom.innerHTML.match(me.tagsRe);
                     cellHTML = cell.dom.innerHTML.replace(me.tagsRe, me.tagsProtect);
                     
                     // populate indexes array, set currentIndex, and replace wrap matched string in a span
                     cellHTML = cellHTML.replace(me.searchRegExp, function(m) {
                        count += 1;
                        if (Ext.Array.indexOf(me.indexes, idx) === -1) {
                            me.indexes.push(idx);
                        }
                        if (me.currentIndex === null) {
                            me.currentIndex = idx;
                        }
                        return '<span class="' + me.matchCls + '">' + m + '</span>';
                     });
                     // restore protected tags
                     Ext.each(matches, function(match) {
                        cellHTML = cellHTML.replace(me.tagsProtect, match); 
                     });
                     // update cell html
                     cell.dom.innerHTML = cellHTML;
                     td = td.next();
                 }
             }, me);

             // results found
             if (me.currentIndex !== null) {
                 me.getSelectionModel().select(me.currentIndex);
                 me.statusBar.setStatus({
                     text: count + ' matche(s) found.',
                     iconCls: 'x-status-valid'
                 });
             }
         }

         // no results found
         if (me.currentIndex === null) {
             me.getSelectionModel().deselectAll();
         }

         // force textfield focus
         me.textField.focus();
     },
    
    /**
     * Selects the previous row containing a match.
     * @private
     */   
    onPreviousClick: function() {
        var me = this,
            idx;
            
        if ((idx = Ext.Array.indexOf(me.indexes, me.currentIndex)) !== -1) {
            me.currentIndex = me.indexes[idx - 1] || me.indexes[me.indexes.length - 1];
            me.getSelectionModel().select(me.currentIndex);
         }
    },
    
    /**
     * Selects the next row containing a match.
     * @private
     */    
    onNextClick: function() {
         var me = this,
             idx;
             
         if ((idx = Ext.Array.indexOf(me.indexes, me.currentIndex)) !== -1) {
            me.currentIndex = me.indexes[idx + 1] || me.indexes[0];
            me.getSelectionModel().select(me.currentIndex);
         }
    },
    
    /**
     * Switch to case sensitive mode.
     * @private
     */    
    caseSensitiveToggle: function(checkbox, checked) {
        this.caseSensitive = checked;
        this.onTextFieldChange();
    },
    
    /**
     * Switch to regular expression mode
     * @private
     */
    regExpToggle: function(checkbox, checked) {
        this.regExpMode = checked;
        this.onTextFieldChange();
    }
});


//point2.

Ext.create 是将类实例化为对象

举例:

Ext.Loader.setConfig({enabled: true});

Ext.Loader.setPath('Ext.ux', '../ux/');

Ext.require([
    'Ext.grid.*',
    'Ext.data.*',
    'Ext.util.*',
    'Ext.tip.QuickTipManager',
    'Ext.ux.LiveSearchGridPanel'
]);

Ext.onReady(function() {    
    Ext.QuickTips.init();
        
    // sample static data for the store
    var myData = [
        ['3m Co',                               71.72, 0.02,  0.03,  '9/1 12:00am'],
        ['Alcoa Inc',                           29.01, 0.42,  1.47,  '9/1 12:00am'],
        ['Altria Group Inc',                    83.81, 0.28,  0.34,  '9/1 12:00am'],
        ['American Express Company',            52.55, 0.01,  0.02,  '9/1 12:00am'],
        ['American International Group, Inc.',  64.13, 0.31,  0.49,  '9/1 12:00am'],
        ['AT&T Inc.',                           31.61, -0.48, -1.54, '9/1 12:00am'],
        ['Boeing Co.',                          75.43, 0.53,  0.71,  '9/1 12:00am'],
        ['Caterpillar Inc.',                    67.27, 0.92,  1.39,  '9/1 12:00am'],
        ['Citigroup, Inc.',                     49.37, 0.02,  0.04,  '9/1 12:00am'],
        ['E.I. du Pont de Nemours and Company', 40.48, 0.51,  1.28,  '9/1 12:00am'],
        ['Exxon Mobil Corp',                    68.1,  -0.43, -0.64, '9/1 12:00am'],
        ['General Electric Company',            34.14, -0.08, -0.23, '9/1 12:00am'],
        ['General Motors Corporation',          30.27, 1.09,  3.74,  '9/1 12:00am'],
        ['Hewlett-Packard Co.',                 36.53, -0.03, -0.08, '9/1 12:00am'],
        ['Honeywell Intl Inc',                  38.77, 0.05,  0.13,  '9/1 12:00am'],
        ['Intel Corporation',                   19.88, 0.31,  1.58,  '9/1 12:00am'],
        ['International Business Machines',     81.41, 0.44,  0.54,  '9/1 12:00am'],
        ['Johnson & Johnson',                   64.72, 0.06,  0.09,  '9/1 12:00am'],
        ['JP Morgan & Chase & Co',              45.73, 0.07,  0.15,  '9/1 12:00am'],
        ['McDonald\'s Corporation',             36.76, 0.86,  2.40,  '9/1 12:00am'],
        ['Merck & Co., Inc.',                   40.96, 0.41,  1.01,  '9/1 12:00am'],
        ['Microsoft Corporation',               25.84, 0.14,  0.54,  '9/1 12:00am'],
        ['Pfizer Inc',                          27.96, 0.4,   1.45,  '9/1 12:00am'],
        ['The Coca-Cola Company',               45.07, 0.26,  0.58,  '9/1 12:00am'],
        ['The Home Depot, Inc.',                34.64, 0.35,  1.02,  '9/1 12:00am'],
        ['The Procter & Gamble Company',        61.91, 0.01,  0.02,  '9/1 12:00am'],
        ['United Technologies Corporation',     63.26, 0.55,  0.88,  '9/1 12:00am'],
        ['Verizon Communications',              35.57, 0.39,  1.11,  '9/1 12:00am'],
        ['Wal-Mart Stores, Inc.',               45.45, 0.73,  1.63,  '9/1 12:00am']
    ];

    /**
     * Custom function used for column renderer
     * @param {Object} val
     */
    function change(val){
        if(val > 0){
            return '<span style="color:green;">' + val + '</span>';
        }else if(val < 0){
            return '<span style="color:red;">' + val + '</span>';
        }
        return val;
    }

    /**
     * Custom function used for column renderer
     * @param {Object} val
     */
    function pctChange(val){
        if(val > 0){
            return '<span style="color:green;">' + val + '%</span>';
        }else if(val < 0){
            return '<span style="color:red;">' + val + '%</span>';
        }
        return val;
    }        
    
    
    // create the data store
    var store = Ext.create('Ext.data.ArrayStore', {
        fields: [
           {name: 'company'},
           {name: 'price',      type: 'float'},
           {name: 'change',     type: 'float'},
           {name: 'pctChange',  type: 'float'},
           {name: 'lastChange', type: 'date', dateFormat: 'n/j h:ia'}
        ],
        data: myData
    });
    
    // create the Grid, see Ext.
    Ext.create('Ext.ux.LiveSearchGridPanel', {
        store: store,
        columnLines: true,
        columns: [
            {
                text     : 'Company',
                flex     : 1,
                sortable : false, 
                dataIndex: 'company'
            },
            {
                text     : 'Price', 
                width    : 75, 
                sortable : true, 
                renderer : 'usMoney', 
                dataIndex: 'price'
            },
            {
                text     : 'Change', 
                width    : 75, 
                sortable : true, 
                dataIndex: 'change',
                renderer: change
            },
            {
                text     : '% Change', 
                width    : 75, 
                sortable : true, 
                dataIndex: 'pctChange',
                renderer: pctChange
            },
            {
                text     : 'Last Updated', 
                width    : 85, 
                sortable : true, 
                dataIndex: 'lastChange'
            }
        ],
        height: 350,
        width: 600,
        title: 'Live Search Grid',
        renderTo: 'grid-example',
        viewConfig: {
            stripeRows: true
        }
    });
});


//point3.

关于prototype,把它当作一个对象,而非类。

JS的处理机制:在处理“.”或者是"[key]"引用的对象的属性或者方法时,现在本身的实例对象this中寻找,找到即返回;若没找到,再从prototype实例对象中去查找。

Ext.namespace("gb");
Wg = gb;
Wg.grid = function (config){}

Ext.apply(Wg.grid.prototype, {
             init:function(param1,param2,...){
             var me = this;
}
});



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