Initialising select2 in sugarcrm sidecar with options to load default list using an app_strings_list or from module's records.

gistfile1.txt

({    
    _render: function() {   
        // load default options using app strings
        this._setSelectField("element_id_here", "", app.lang.getAppListStrings("cstm_lead_source_list") , false, null, null, null); 
        // if you want to load default selected value
        $('#element_id_here').select2('val','id_in_the_option_list');
        // load options from records of a module
        this._setSelectField("element_id_of_the_field", "", null, "Accounts", "name", this.getPersonRecordList);       
    },
    getPersonRecordList: function(strName, strModule, fieldname, callback) {
        // set local scope
        var self = this;  
        // do we have name
        if (strName) {  
            // setup id as default field to select, 
            var objFilter = {                
                   "max_num": 10,
                   "fields": ["id"],
                   "order_by": "date_modified:DESC"
                },                
                arFilter = [];

            switch (fieldname) {
                case 'name':
                    arFilter.push(
                        {
                            "name":{
                                "$contains": strName
                            }
                        }                    
                    );
                    // add the filter parameter
                    objFilter.filter = [
                      {
                        "$or": arFilter
                      }
                    ];
                    // and add as addition fields                
                    objFilter.fields.push(fieldname);                      
                    break;               
                case 'full_name':
                    arFilter.push(
                        {
                            "first_name":{
                                "$contains": strName
                            }
                        },
                        {
                            "last_name":{
                                "$contains": strName
                            }
                        }
                    );
                    // add the filter parameter
                    objFilter.filter = [
                      {
                        "$or": arFilter
                      }
                    ];
                    // and add as addition fields                
                    objFilter.fields.push(fieldname);  
                    break;
                case 'assigned_user_name':
                    arFilter.push({
                        "assigned_user_id" : strName                        
                    });                    
                    // add the filter parameter
                    objFilter.filter = arFilter;
                    // and add as addition fields                
                    objFilter.fields.push('full_name');
                    objFilter.fields.push(fieldname);               
                default:
                    break;
            }            
            // build url
            var strUrl = app.api.buildURL(strModule, null, null, objFilter);                     
            // call function
            app.api.call('GET', strUrl, null, {  
                success: function (data) {                      
                    // initialise result
                    var objData = {
                        results: []
                    };                    
                    // Loop through each brand
                    $.each(data.records, function(strKey, objDetail) {     
                        // Add the result
                        objData.results.push({
                            id: objDetail.id,
                            text: objDetail[fieldname]
                        });
                    });                    
                    // call select2 callback
                    callback(objData);
                }  
            });  
        }
        // return
        return false;
    },    
    _setSelectField: function(strFieldId, objSelected, arData, strModule, strFieldName, objFunction) {        
        // initiliase scope
        var self = this;        
        // initialise select2
        $("#" + strFieldId).select2({               
            allowClear: true,            
            width: '100%',                        
            initSelection: function (element, callback) {
                // do we have default value
                if (objSelected) {
                    // initialise default list
                    callback({id: objSelected.id, text: objSelected.text });
                }
            },
            query: function(query) {
                // Initialise the results
                var objData = {
                    results: []
                };
                // do we have a function call?
                if (objFunction != null) {                                    
                    // call function
                    objFunction(query.term, strModule, strFieldName, query.callback);
                } else {
                    // Do we have results?
                    if (arData != undefined) {                        
                        // Loop through each brand
                        $.each(arData, function(strKey, objDetail) {                            
                            // Add the result
                            objData.results.push({
                                id: strKey,
                                text: objDetail
                            });                                
                        });
                    } else {
                        // Add warning message
                        objData.results.push({
                            id: "",
                            text: "No Data to Load"
                        });
                    }                     
                    // invoke callback
                    query.callback(objData);
                }                
            }
        });
    }    
})