Extjs Grid doesn't show any data

Question

I created the following grid component:

MyApp.grids.RelationshipMemberGrid = Ext.extend(Ext.grid.GridPanel, {
    autoHeight: true,
    iconCls: 'icon-grid',
    title: 'Relationship Members',
    frame: true,
    viewConfig: { forceFit: true },
    relationshipId: null,
    documentId: null,

    initComponent: function () {
        if (this.verifyParameters()) {
            // Initiate functionality
            this.columns = this.buildColumns();
            this.view = this.buildView();
            this.store = this.buildStore();
            this.store.load();
        }

        MyApp.grids.RelationshipMemberGrid.superclass.initComponent.call(this);
    },

    verifyParameters: function () {
        // Verification code
    },

    buildColumns: function () {
        return [{
            header: 'Id',
            dataIndex: 'Id',
            sortable: true,
            width: 10
        }, {
            header: 'Type',
            dataIndex: 'ObjType',
            sortable: true,
            width: 10
        }, {
            header: 'Name',
            dataIndex: 'Name',
            sortable: true
        }];
    },

    buildView: function () {
        return new Ext.grid.GroupingView({
            forceFit: true,
            groupTextTpl: '{text} ({[values.rs.length]} {[values.rs.length > 1 ? "Members" : "Member"]})'
        });
    },

    buildStore: function () {
        return new Ext.data.GroupingStore({
            url: MyAppUrls.ListRelationshipMembers,
            baseParams: { relationshipId: this.relationshipId },
            root: 'data',
            fields: ['Id', 'ObjType', 'Name'],
            sortInfo: { field: 'Name', direction: 'ASC' },
            groupField: 'ObjType'
        });
    }
});

The grid renders correctly, and the URL that is mapped to MyAppUrls.ListRelationshipMembers is correct. The data is being retrieved, and the ListRelationshipMembers URL is returning the following JSON:

{"data":[{"Id":1,"ObjType":"topic","Name":"Test2"}]}

Yet, even though the grid is rendered (columns, borders, etc..) no data is showing in the actual grid though. Since this is my first time using a data store, I am unsure of what I am doing wrong. Any help would be appreciative.

Edit:

I tried updating the store to have a reader via the following code:

    return new Ext.data.GroupingStore({
        url: MyAppUrls.ListRelationshipMembers,
        baseParams: { relationshipId: this.relationshipId },
        fields: ['Id', 'ObjType', 'Name'],
        sortInfo: { field: 'Name', direction: 'ASC' },
        reader: new Ext.data.JsonReader({
            root: 'data' 
        }),
        groupField: 'ObjType'
    });

No change, the datagrid is not being filled with the records

Answer 1

Evan is correct. Your biggest problem is a lack of a reader. That and the validation stub you left in there needed to return true. If you can't just drop this code in and have it work you have some other problem.

MyApp.grids.RelationshipMemberGrid = Ext.extend(Ext.grid.GridPanel, {
    autoHeight: true,
    iconCls: 'icon-grid',
    title: 'Relationship Members',
    frame: true,
    viewConfig: { forceFit: true },
    relationshipId: null,
    documentId: null,

        initComponent: function () {
        if (this.verifyParameters()) {
            // Initiate functionality
            this.columns = this.buildColumns();
            this.view = this.buildView();
            this.store = this.buildStore();
            this.store.load();
        }

        MyApp.grids.RelationshipMemberGrid.superclass.initComponent.call(this);
    },

    verifyParameters: function () {
        // Verification code
        return true;
    },

    buildColumns: function () {
        return [{
            header: 'Id',
            dataIndex: 'Id',
            sortable: true,
            width: 10
        }, {
            header: 'Type',
            dataIndex: 'ObjType',
            sortable: true,
            width: 10
        }, {
            header: 'Name',
            dataIndex: 'Name',
            sortable: true
        }];
    },

    buildView: function () {
        return new Ext.grid.GroupingView({
            forceFit: true,
            groupTextTpl: '{text} ({[values.rs.length]} {[values.rs.length > 1 ? "Members" : "Member"]})'
        });
    },

    buildStore: function () {
        return new Ext.data.GroupingStore({
            url: MyAppUrls.ListRelationshipMembers,
            baseParams: { relationshipId: this.relationshipId },
            reader: new Ext.data.JsonReader({
                root: 'data',
                fields: ['Id', 'ObjType', 'Name'],
                sortInfo: { field: 'Name', direction: 'ASC' },
                groupField: 'ObjType'
            })
        });
    }
});

Answer 2

Think you need to do a couple of things here: firstly, as mentioned by Evan, you need to add a reader to your store, like this:

buildStore: function () {
    return new Ext.data.Store({
        url: MyAppUrls.ListRelationshipMembers,
        baseParams: { relationshipId: this.relationshipId },
        fields: ['Id', 'ObjType', 'Name'],
        sortInfo: { field: 'Name', direction: 'ASC' },
        reader: new Ext.data.JsonReader({
            root: 'data' 
        })
    });
}

I've changed the store type here to something simpler - was there a particular reason you were using GroupingStore? Note that the root is specified in the reader, not the store itself.

Then, in your columns, I'd tend to add a renderer to explicitly determine what each column will display, such as:

buildColumns: function () {
    return [{
        header: 'Id',
        dataIndex: 'Id',
        sortable: true,
        width: 10,
        renderer: function (value, metaData, record) {
            return record.data.Id
        }
    } ... ];
}

I've got into the habit of using renderers, since I modify the content of my column cells quite heavily in my grids. Notice here the arguments being passed to the renderer function; there are a few more you can pass in - see the ExtJS API if you need more info on what you can actually access. On that note, the API documentation is pretty good - it can take some digging into but definitely worth your time if you're working with ExtJS a lot.

Answer 3

You haven't specified a reader on your store, you need to specify the root in the JsonReader.