passing the number of records that are selected in the grid to another form control:

First of all  create  a new form "GridLinesCounter".
After that add the intedit control in that  form Design and change the property auto declaration to yes.
Create a new menu item and add this form to that menu item.

Go to the sales table list page form and add the created menu item in the ActionPane.
Then  override the clicked method in that menu item botton.

void clicked()
{
     FormDataSource fds;
    Common common;
    int counter;
    Args                args;
    FormRun             formrun;
    ;
    //super();
                     args = new Args();

    fdS = SalesTable_ds;
    for (common = fdS.getFirst(true) ? fdS.getFirst(true) : SalesTable_ds.cursor(); common; common = fdS.getNext())
    {
        counter++;
    }
    args.parm(int2str(counter));
    args.name(formstr(gridlinescounter));
    formRun = classFactory.formRunClass(Args);
    formRun.init();
    formrun.run();
    formrun.wait();
    info(int2str(counter));
}


Open the "GridLinesCounter" form and add init method.

public void init()
{
    str counter;
    counter = element.args().parm();
    super();
   intedit.value(str2int(Counter));
}

Now,go to salestablelistpage form and select some records .

Then click newmenuitem button (gridlinescounter) then a form will be opened showing the no of records selected.

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Another code to get the same result .
void clicked()
{
    int                 recordsCount;
    HcmPosition         hcmPosition1;
    container           con;
    Args                args;
    str                 multiSelectString;
    FormRun             formrun;
    args = new Args();
    // gets the total records selected
    recordsCount = HcmPosition_ds.recordsMarked().lastIndex();

    hcmPosition1= HcmPosition_ds.getFirst(1);

    while(hcmPosition1)
    {
        // storing recid of selected record in container
        con = conIns(con,1, hcmPosition1.RecId);
        // converting container to string with comma separated
        multiSelectString = con2Str(con,',');

        hcmPosition1= HcmPosition_ds.getNext(); // moves to next record
    }
    // passing string
    args.parm(multiSelectString);
    args.name(formstr(CH_RecrutmentForm));
    formRun = classFactory.formRunClass(Args);
    formRun.init();
    formrun.run();
    formrun.wait();
}

public void init()
{
    container con;
    int i;
    str multipleRecords;
    int record;
    super();
    // getting string value from caller
    multipleRecords = element.args().parm();
    // string to container
    con = str2con(multipleRecords,",");

     for(i = 1;i<= conLen(con) ;i++)
    {
           intedit.value(i);    
    }  
}