jqGrid boolean or enumeration dropdown filtering for columns

I'm using jqGrid to display tabular data on my first ASP.NET MVC 3 and find it really useful, particularly filtering down data. For string-type I use the column-filtering with "contains" and that works wonderfully for culling out the strings. For the date data I use the date picker. Great.

Now I've got a few columns (e.g., "Contains nuts") which are essentially boolean values. I want to provide a way to filter these. Right now they are displayed as "true" and "false" and use the same string-based filtering that my string-type columns use. That's a bit clunky. I think what I'd like to do instead is have a way to choose one of three values (true/false/both) via a dropdown mechanism.

My current colModel has an entry like so for my 'boolean' field:

{ name: 'ContainsNuts', 
  index: 'ContainsNuts', 
  align: 'left', 
  searchoptions: { sopt: ['eq, 'ne']} 
}

which only works when the user types in 'false' or 'true' - again, clunky.

For a few other columns, I wanted to use dropdowns for enumerations, e.g., I have a 'Cones' column, since there are quite a few rows and I page the results - using the auto complete text filtering is a bit hit-or-miss for the user to find all the possible values. Hope that makes sense.

So what I've tried is this - I created a controller action that looks like so:

public JsonResult AvailableCones()
{
   var context = new IceCreamEntities();
   var query = context.Cones.AsQueryable().Distinct();
   List<string> all = query.Select(m => m.Name).ToList();
   return Json(all, JsonRequestBehavior.AllowGet);
}

And I did something like this [perhaps convoluted approach] to create a dropdown selection in the filtering dialog for Cones in my document ready:

...

createSearchSelection = function (someValues) {
   var outputValues = "";
   if (someValues && someValues.length) {
      for (var i = 0, j = someValues.length; i < j; ++i) {
         var entry = someValues[i];
         if (outputValues.length > 0) {
            outputValues += ";";
         }
         outputValues += entry + ":" + entry;
      }
   }
   return outputValues;
}

setTheSearchSelections = function (colName, url){
   $('#icecreamgrid').jqGrid('setColProp', colName,
      {
         stype: 'select',
         searchoptions: {
            value: createSearchSelection(url),
            sopt: ['eq']
         }
      });
}

gotData = function(data) {
   setTheSearchSelections('ConeType', data);
}

var url = "/IceCream/AvailableConeTypes";
$.get(url, null, gotData);

The result is that I get a drop-down for the ConeType column in the search dialog and the correct rows shows up in the column. Great. That's pretty cool that it works开发者_如何转开发.

What I don't know how to do, however, is to get a dropdown to show up in my column header filter just like the one that now shows up in the filter dialog. How can I augment what I have to make this happen? Secondly, how can I make what I've got work for boolean values?

---

First part of your question is the displaying and filtering of the boolean values. I use checkboxes to display such values. In difference on your case I have typically many such columns. To reduce the size of the JSON data I use "1" and "0" instead of "true" and "false". Next I use the following column settings

formatter: 'checkbox', align: 'center', width: 20,
edittype: 'checkbox', editoptions: { value: "1:0" },
stype: "select", searchoptions: { sopt: ['eq', 'ne'], value: "1:Yes;0:No"

So for the searching the user have to choose "Yes" or "No" in the select box. Because I have many of such columns I defined templateCeckbox object in one JavaScript file which I include on every page of the project:

my.templateCeckbox = {
    formatter: 'checkbox', align: 'center', width: 20,
    edittype: 'checkbox', editoptions: { value: "1:0" },
    stype: "select", searchoptions: { sopt: ['eq', 'ne'], value: "1:Ja;0:Nein" }
};

Then the typical column definition is

{
    name: 'IsInBasis', index: 'InBasis', template: my.templateCeckbox,
    cellattr: function () { return ' title="TS-Basis"'; }
},

(see the answer for details about the column templates). I find also practical if the tooltip shown if one hover the checkbox will be the text close to the column header. So I use cellattr attribute. In case of having many columns with the checkboxes it improves the usability a little.

To be able to display many columns with chechboxes I use personally vertical column headers. I recommend you to read the old answer which could be additionally interesting because it describes how to implement quick filtering of the data with respect of external checkbox panel.

Now about the building of the selects for the 'Cones' column. If you has AvailableCones action which provide the list of possible options like array (list) of strings you should use dataUrl:'/IceCream/AvailableConeTypes' instead of value: createSearchSelection(url) as the searchoptions. You well add only the buildSelect function which I described in "UPDATED" part of the answer.

{
    name: 'ConeType', width: 117, index: 'ConeType', editable: true, align: 'center',
    edittype: 'select', stype: 'select',
    editoptions: {
        dataUrl: urlBase + '/AvailableConeTypes',
        buildSelect: my.buildSelect
    },
    searchoptions: {
        dataUrl: urlBase + '/AvailableConeTypes',
        buildSelect: my.buildSelect
    }
}

where

my.buildSelect = function(data) {
    var response = jQuery.parseJSON(data.responseText),
        s = '<select>', i, l, ri;

    if (response && response.length) {
        for (i=0, l=response.length; i<l; i += 1) {
            ri = response[i];
            s += '<option value="' + ri + '">' + ri + '</option>';
        }
    }
    return s + '</select>';
};

---

This line of code shows a True,False dropdownlist for a column that has true, false values:

{
 name: 'SReqdFlag', index: 'SReqdFlag', editable: true, edittype: 'select',  editoptions: { value: '"":Select;true:True;false:False' }
}

Hope that helps!