Adding filter on display fields in ax2012

Here is a sample example scenario where you add a display field on the form and make this field to be allowed to filter.

Create a table TEST

Create form TEST

Data source à TEST
Add fields Test_Id, Test_ActivityNumber, ActivityName from the datasource TEST

FormControl à Activity name à auto declaration YES
Data method à displayActivityName

Then override context method on the formcontrol and write the following code :

public void context()

{

    int             selectedMenu;

    formrun         fr;

    Args            ag;

    Name            strtext;

    querybuilddataSource qb1;

    queryrun    qr;

    query       q;

    PopupMenu menu = new PopupMenu(element.hWnd());

    int a = menu.insertItem('Filter By Field');

    int b = menu.insertItem('Filter By Selection');

    int c = menu.insertItem('Remove Filter');

    ;

    q   = Test_ds.query();

    qb1 = q.dataSourceTable(tablenum(Test));

    qb1 = qb1.addDataSource(TableNum(smmActivities));

    qb1.addLink(FieldNum(Test,ActivityNumber),FieldNum(smmActivities,ActivityNumber));

    selectedMenu = menu.draw();

    switch (selectedMenu)

    {

    case -1: //Filter by field

            break;

    case a:

            ag = new args('SysformSearch');

            fr = new formrun(ag);

            fr.run();

            fr.wait();

//Reading User entered value for filter process

            strtext = fr.design().controlName('FindEdit').valueStr();

            if(strtext)

            {

//Creating a query for filter

                qb1.addRange(FieldNum(smmActivities,Purpose)).value(strtext);

                Test_ds.query(q);

                Test_ds.executeQuery();

            }

            break;

    case b:                                      // Filter By Selection

            qb1.addRange(FieldNum(smmActivities,Purpose)).value(ActivityName.valueStr());

            Test_ds.query(q);

            Test_ds.executeQuery();

            break;

    case c :                                      // Remove Filter

            q   = new Query();

            qb1 = q.addDataSource(tablenum(Test));

            qb1.clearLinks();

            qb1.clearRanges();

            Test_ds.query(q);

            Test_ds.removeFilter();

            break;

    Default:

            break;

    }

}