Render dynamic components in ExtJS 4 GridPanel Column with Ext.create

Question

I've got an ExtJS (4.0.7) GridPanel that I'm populating from a store. The values that I display in the GridPanel's column need to have a different view depending on the type of data that's in the record.

The ultimate goal is that records with "double" or "integer" value for the record's type property present a slider to the user that they can adjust, and a type of "string" just renders some read-only text.

I've created a custom Column to do this. It inspects the type in the renderer and determines what to render.

I've got the "string" working fine with the code below, but struggling with how I can dynamically create and render the more complicated slider control in the column.

This simplified example is just trying to render a Panel with a date control in it as if I can get that going, I can figure out the rest of the slider stuff.

Ext.define('MyApp.view.MyColumn', {
    extend: 'Ext.grid.column.Column',
    alias: ['widget.mycolumn'],

    stringTemplate: new Ext.XTemplate('code to render {name} for string items'),

    constructor: function(cfg){
        var me = this;
        me.callParent(arguments);

        me.renderer = function(value, p, record) {
            var data = Ext.apply({}, record.data, record.getAssociatedData());

            if (data.type == "string") {
                return me.renderStringFilter(data);
            } else if (data.type == "double" || data.type == "integer") {
                return me.renderNumericFilter(data);
            } else {
                log("Unknown data.type", data);

        };
    },

    renderStringFilter: function(data) {
        // this works great and does what I want
        return this.stringTemplate.apply(data);
    },

    renderNumericFilter: function(data) {

        // ***** How do I get a component I "create" to render 
        // ***** in it's appropriate position in the gridpanel?
        // what I really want here is a slider with full behavior
        // this is a placeholder for just trying to "create" something to render

        var filterPanel = Ext.create('Ext.panel.Panel', {
            title: 'Filters',
            items: [{
                xtype: 'datefield',
                fieldLabel: 'date'
            }],
            renderTo: Ext.getBody() // this doesn't work
        });
        return filterPanel.html;  // this doesn't work
    }
});

My problem really is, how can I Ext.create a component, and have it render into a column in the gridpanel?

Answer 1

There are a few ways that I have seen this accomplished. Since the grid column is not an Ext container it can not have Ext components as children as part of any configuration the way other container components can. Post grid-rendering logic is required to add Ext components to cells.

This solution modifies your custom column render so that it puts a special css class on the rendered TD tag. After the grid view is ready, the records are traversed and the custom class is found for appropriate special columns. A slider is rendered to each column found.

The code below is a modified version of the ext js array grid example provided in the Sencha examples. The modification mixes in the custom column renderer and the post grid rendering of sliders to TD elements.

This example only includes enough modification of the Sencha example to show the implementation ideas. It lacks separated view and controller logic.

This is modified from here

 Ext.require([
     'Ext.grid.*',
     'Ext.data.*',
     'Ext.util.*',
     'Ext.data.Model'
 ]);


 Ext.onReady(function() {

     // sample static data for the store
     Ext.define('Company', {
         extend: 'Ext.data.Model',
         fields: ['name', 'price', 'change', 'pctChange', 'lastUpdated', 'type']
     });

     var myData = [
         ['3m Co', 71.72, 2, 0.03, '9/1/2011', 'integer'],
         ['Alcoa Inc', 29.01, 4, 1.47, '9/1/2011', 'string'],
         ['Altria Group Inc', 83.81, 6, 0.34, '9/1/2011', 'string'],
         ['American Express Company', 52.55, 8, 0.02, '9/1/2011', 'string'],
         ['American International Group, Inc.', 64.13, 2, 0.49, '9/1/2011', 'integer'],
         ['AT&T Inc.', 31.61, 4, -1.54, '9/1/2011', 'integer'],
         ['Boeing Co.', 75.43, 6, 0.71, '9/1/2011', 'string'],
         ['Caterpillar Inc.', 67.27, 8, 1.39, '9/1/2011', 'integer'],
         ['Citigroup, Inc.', 49.37, 1, 0.04, '9/1/2011', 'integer'],
         ['E.I. du Pont de Nemours and Company', 40.48, 3, 1.28, '9/1/2011', 'integer'],
         ['Exxon Mobil Corp', 68.1, 0, -0.64, '9/1/2011', 'integer'],
         ['General Electric Company', 34.14, 7, -0.23, '9/1/2011', 'integer']
     ];

     // create the data store
     var store = Ext.create('Ext.data.ArrayStore', {
         model: 'Company',
         data: myData
     });

     // existing template
     stringTemplate = new Ext.XTemplate('code to render {name} for string items');

     // custom column renderer
     specialRender = function(value, metadata, record) {
         var data;

         data = Ext.apply({}, record.data, record.getAssociatedData());

         if (data.type == "string") {
             return stringTemplate.apply(data);;
         } else if (data.type == "double" || data.type == "integer") {
             // add a css selector to the td html class attribute we can use it after grid is ready to render the slider
             metadata.tdCls = metadata.tdCls + 'slider-target';
             return '';
         } else {
             return ("Unknown data.type");

         }
     };

     // create the Grid
     grid = Ext.create('Ext.grid.Panel', {
         rowsWithSliders: {},
         store: store,
         stateful: true,
         stateId: 'stateGrid',
         columns: [{
             text: 'Company',
             flex: 1,
             sortable: false,
             dataIndex: 'name'
         }, {
             text: 'Price',
             width: 75,
             sortable: true,
             renderer: 'usMoney',
             dataIndex: 'price'
         }, {
             text: 'Change',
             width: 75,
             sortable: true,
             dataIndex: 'change',
             renderer: specialRender,
             width: 200
         }, {
             text: '% Change',
             width: 75,
             sortable: true,
             dataIndex: 'pctChange'
         }, {
             text: 'Last Updated',
             width: 85,
             sortable: true,
             renderer: Ext.util.Format.dateRenderer('m/d/Y'),
             dataIndex: 'lastUpdated'
         }],
         height: 350,
         width: 600,
         title: 'Irm Grid Example',
         renderTo: 'grid-example',
         viewConfig: {
             stripeRows: true
         }
     });

     /**
      * when the grid view is ready this method will find slider columns and render the slider to them
      */
     onGridViewReady = function() {
         var recordIdx,
             colVal,
             colEl;

         for (recordIdx = 0; recordIdx < grid.store.getCount(); recordIdx++) {
             record = grid.store.getAt(recordIdx);
             sliderHolder = Ext.DomQuery.select('.slider-target', grid.view.getNode(recordIdx));
             if (sliderHolder.length) {
                 colEl = sliderHolder[0];

                 // remove div generated by grid template - alternative is to use a new template in the col
                 colEl.innerHTML = '';

                 // get the value to be used in the slider from the record and column
                 colVal = record.get('change');

                 // render the slider - pass in the full record in case record data may be needed by change handlers
                 renderNumericFilter(colEl, colVal, record)
             }
         }

     }

     // when the grids view is ready, render sliders to it
     grid.on('viewready', onGridViewReady, this);

     // modification of existing method but removed from custom column 
     renderNumericFilter = function(el, val, record) {

         var filterPanel = Ext.widget('slider', {
             width: 200,
             value: val,
             record: record,
             minValue: 0,
             maxValue: 10,
             renderTo: el
         });

     }
 });