SDK2: sorting custom column in a rally grid - rally

Question

I have a rally grid that shows defects. I want do add a column that shows the number of days a defect has been open.
I know can do that by adding a custom renderer in the column configs, but I would also like to sort on this column. Unfortunately, the renderer does not change the sorting of the column.
I think I might be able to use the convert() function on the store instead to create a new virtual column (in this case openAgeDays), but I'm not sure how to do this from the constructor--I presume I make some changes to storeConfig?
Does anyone have an example of how to use a convert function (assuming that this is the right way to do it) to add a new virtual, sortable column to a rally grid?
this.grid = this.add({
xtype: 'rallygrid',
model: model,
disableColumnMenus: false,
storeConfig: [...]

Answer 1

As is the answer in the duplicate, you can add a doSort to the column:
{dataIndex: 'Parent', name: 'Parent',
doSort: function(state) {
var ds = this.up('grid').getStore();
var field = this.getSortParam();
console.log('field',field);
ds.sort({
property: field,
direction: state,
sorterFn: function(v1, v2){
console.log('v1',v1);
console.log('v2',v2);
if (v1.raw.Parent) {
v1 = v1.raw.Parent.Name;
} else {
v1 = v1.data.Name;
}
if (v2.raw.Parent) {
v2 = v2.raw.Parent.Name;
} else {
v2 = v2.data.Name;
}
return v1.localeCompare(v2);
}
});
},
renderer: function(value, meta, record) {
var ret = record.raw.Parent;
if (ret) {
return ret.Name;
} else {
meta.tdCls = 'invisible';
return record.data.Name;
}
}
},