ListGrid.refreshData doesn't trigger dataChanged

[claudiobosticco]

SmartClient Version: SNAPSHOT_v12.1d_2019-03-27/AllModules Development Only (built 2019-03-27)
and
SmartClient Version: v11.1p_2019-03-27/AllModules Development Only (built 2019-03-27)

Hello, I've just noticed that ListGrid.refreshData doesn't trigger dataChanged, you may try this modified sample (id=gridComponents):

isc.ToolStrip.create({
    ID: "gridEditControls",
    width: "100%", height:24, 
    members: [
        isc.Label.create({
            padding:5,
            ID:"totalsLabel"
        }),
        isc.LayoutSpacer.create({ width:"*" }),
        isc.ToolStripButton.create({
            title:"Refresh Data",
            click: "countryList.refreshData()"
        })
    ]
});

isc.ListGrid.create({
    ID: "countryList",
    width:500, height:425, alternateRecordStyles:true,
    dataSource: countryDS,
    fields:[
        {name:"countryCode", title:"Code", width:50},
        {name:"countryName", title:"Country"},
        {name:"capital", title:"Capital"},
        {name:"continent", title:"Continent"}
    ],
    autoFetchData: true,
    showFilterEditor: true,
    canEdit:true,
    editEvent:"none",
    gridComponents:["header", "filterEditor", "body", gridEditControls],
    dataChanged : function () {
        isc.logEcho('dataChanged')
        this.Super("dataChanged", arguments);
        var totalRows = this.data.getLength();
        if (totalRows > 0 && this.data.lengthIsKnown()) {
            totalsLabel.setContents(totalRows + " Records");
        } else {
            totalsLabel.setContents(" ");
        }
    }
})

If you press 'refresh data' you'll see that 'dataChanged' isn't logged.

Is it by design? Reading the dataChanged docs it seems that it would be called even in this case.

[Isomorphic]

Yes, this is by design. You can use the callback of refreshData if you want a notification.

[claudiobosticco]

Thanks, maybe a note in the documentation which specifies that in the case of refreshData it isn't called, would be useful, as a simple implementation like that sample taken from the showcase (which I've used extensively in my applications) seems broken if one uses refreshData.

[Isomorphic]

We've added a note about dataChanged() not being called to the docs for refreshData() back to SC 11.1p. It should be picked up by the next nightly builds.

[claudiobosticco]

Hello, while trying to find a way to add a record count for a grid, based on a single method to implement/observe (without the need to worry about other side effects which might change the record count), I'm trying this:

isc.ListGrid.create({
    ID: "grid",
    width:500, height:300, alternateRecordStyles:true,
    dataSource: supplyItem,
    fields:[
        {name:"SKU"},
        {name:"itemName"},
        {name:"description"},
        {name:"category"}
    ],

    autoFetchData: true,
    showFilterEditor: true,
    filterOnKeypress: true,
    fetchDelay: 500,
    showFilterEditor:true,
    showGridSummary:true,
    getGridSummaryFunction: function(field){
        var data = grid.data;
        var lengthIsKnown = (isc.isA.ResultSet(data) && data.lengthIsKnown()) || true;
        if (lengthIsKnown && field.name === 'category') {
            foo.setContents(grid.data.getLength());
        }
    }
})

grid.addChild(isc.Label.create({ID:"foo", height:30, width:1, border:"1px solid red", snapTo:"BR"}));

Is it reliable this technique based on getGridSummaryFunction ?
Will it always be called when the length is known?
Will it be called for all changes that could alter the record count?

The only other technique I could think of is using summaryRowDataSource, but it seems a waste as a query for counting the records is already been executed.

[Isomorphic]

This may work today, but we don't document the timing of when we call that method, so it would not be something you could rely upon in the future.