I took a look into the code of Ext.grid.column.CheckColumn
, and I think the less intrusive way to achieve what you want is to:
Use a tweaked model that prevent modification on the desired condition.
Override the column renderer
to add the disabled class for record that are not checkable.
Example:
// Using anonymous model class just to show that you can do this,
// if you don't need to define an application-wide model
var model = Ext.define(null, {
extend: 'Ext.data.Model'
,fields: ['id', 'status', 'checkable']
// example data
,proxy: {
type: 'memory'
,reader: 'array'
,data: [
[1, true, true]
,[2, true, false]
,[3, false, true]
,[4, false, false]
]
}
// 1. Prevent modification on certain conditions
,set: function(field, value) {
if (field === 'status' && !this.get('checkable')) {
return null;
} else {
return this.callParent(arguments);
}
}
});
Ext.widget('grid', {
renderTo: Ext.getBody()
,height: 200
,store: {
model: model
,autoLoad: true
}
,columns: [{
text: 'id'
,dataIndex: 'id'
},{
text: 'status'
,dataIndex: 'status'
,xtype: 'checkcolumn'
// 2. Custom renderer to reflect "checkability"
,renderer: function(value, meta, record) {
var cssPrefix = Ext.baseCSSPrefix,
cls = [cssPrefix + 'grid-checkcolumn'];
if (
this.disabled
// this is the added condition for disabledCls
|| !record.get('checkable')
) {
meta.tdCls += ' ' + this.disabledCls;
}
if (value) {
cls.push(cssPrefix + 'grid-checkcolumn-checked');
}
return '<img class="' + cls.join(' ') + '" src="' + Ext.BLANK_IMAGE_URL + '"/>';
}
},{
text: 'modifiable'
,dataIndex: 'checkable'
,xtype: 'booleancolumn'
}]
});