Which foreign key field will be used as a TreeGrid "tree" field ?

[michalg]

Hi,
I have DataSource similar to EmployeeXmlDS used in TreeGrid showcase examples. The only difference is that I have got more than one foreign key defined prior "ReportsTo" (otherField is a foreign key and it is placed BEFORE tree relationship field reportsToField):

   public EmployeeXmlDS(String id) {

        setID(id);
        setTitleField("Name");
        setRecordXPath("/List/employee");
        DataSourceTextField nameField = new DataSourceTextField("Name", "Name", 128);

        DataSourceIntegerField employeeIdField = new DataSourceIntegerField("EmployeeId", "Employee ID");
        employeeIdField.setPrimaryKey(true);
        employeeIdField.setRequired(true);

        DataSourceIntegerField otherField = new DataSourceIntegerField("Other", "Other");
        otherField.setRequired(true);
        otherField.setForeignKey("OtherDS.id");

        DataSourceIntegerField reportsToField = new DataSourceIntegerField("ReportsTo", "Manager");
        reportsToField.setRequired(true);
        reportsToField.setForeignKey(id + ".EmployeeId");
        reportsToField.setRootValue("1");

        setFields(nameField, employeeIdField, otherField, reportsToField);

        setDataURL("ds/test_data/employees.data.xml");
        setClientOnly(true);
    }
}

I have noticed that TreeGrid bound to such DataSource takes FIRST foreign key field as the tree relationship which is otherField in my example. Is there a way to somehow point DataSource or TreeGrid which field should be considered as "tree" field ?
Thanks,
MichalG

[davidj6]

Take a look at the Tree Data Binding docs for details on the fields used to create the tree. Then take a look at the TG.fetchData() and Tree docs to set the idField and parentIdField as desired.

[michalg]

Thanks for the link. However according this part of the documentation:
"com.smartgwt.client..ResultTrees are created for you by the TreeGrid when you set dataSource, but you can pass an initial dataset to a databound TreeGrid by setting initialData. The idField is derived from the dataSource you provide to the TreeGrid - the first field marked as primaryKey:true becomes the idField of the ResultTree. The parentIdField is found by looking for a field that has a foreignKey property pointing to the idField."
I would understand that in case of ResultTree created as the result of setting DataSource, the parentIdField is chosen for me.

I did try to setParentId for the Tree this way:

   public EmployeeXmlDS() {

        setID("EmployeeDS");
        setTitleField("Name");

        DataSourceTextField nameField = new DataSourceTextField("Name", "Name", 128);

        DataSourceIntegerField employeeIdField = new DataSourceIntegerField("id", "Employee ID");
        employeeIdField.setPrimaryKey(true);
        employeeIdField.setRequired(true);

        DataSourceIntegerField otherField = new DataSourceIntegerField("Other", "Other");
        otherField.setRequired(true);
        otherField.setForeignKey("OtherDS.id");

        DataSourceIntegerField reportsToField = new DataSourceIntegerField("ReportsTo", "Manager");
        reportsToField.setRequired(true);
        reportsToField.setForeignKey("EmployeeDS.id");
        reportsToField.setRootValue("1");

        setFields(nameField, employeeIdField, otherField, reportsToField);
    }
}

    public void onModuleLoad() {
        TreeGrid employeeTreeGrid = new TreeGrid();
        employeeTreeGrid.setAutoFetchData(true);
        employeeTreeGrid.setDataSource(EmployeeXmlDS.getInstance());
        employeeTreeGrid.getTree().setParentIdField("ReportsTo");       
        employeeTreeGrid.draw();
    }

but still I am observing wrong criteria for the OtherDS instead of EmployeeDS in the request.
MichalG

[davidj6]

All of this is true, however, see TG.setDataProperties for a way to customize the Tree. Just setup a Tree template as desired, apply it there and then let SGWT create the resulting Tree from your DataSource.