Database Manual · Chapter 7

Screen Bindings

The sample's UI splits into two parts.

Screen	Role	Core bindings
ViewRun	Main — DataGrid + 6 buttons	`Data::DispData` (rows array) · `Data::SelectIndex` (selected index)
ModifyDlg	Record-edit dialog	`Data::EditId` · `EditOrderNo` · `EditMenuName` · `EditEndTime` and 5 more

Scripts only update data (array DispData[], int EditWeightG, …); the controls re-paint themselves to follow — that wiring is the heart of this chapter.

1) ViewRun · XDataGrid Binding

Data.xms declares two variables:

// One CSV line = one row (id,order_no,menu_name,start_time,end_time,weight_g,result,is_error)
array DispData[] = {"",};
 
// XDataGrid auto-updates this with the current selected row index (-1 = none)
int SelectIndex = -1;

Set two properties on the XDataGrid in the Property Editor:

Property	Value	Meaning
ItemsSourceDataName	`Data::DispData`	The row array the data grid displays
SelectIndexDataName	`Data::SelectIndex`	When user picks a row, this gets 0..N-1; -1 = no selection

CSV row format

Each element of DispData is one comma-joined string:

"42,O1042,Latte,2026-05-06 09:31:02,2026-05-06 09:31:30,300,Done,0"

The end of DB_Refresh() builds this format directly from GetRowArray(i).

Columns definition

If the DataGrid's Columns property defines the same 8 columns, the N-th token of CSV maps automatically to the N-th column.

Index	Header	Format / Width recommended
0	id	width 60
1	order_no	width 90
2	menu_name	width 120
3	start_time	width 160
4	end_time	width 160
5	weight_g	format `0.0`, width 80
6	result	width 80
7	is_error	width 60

Refresh flow

The script just does DispData.Clear() → repeated Add(). Each line built in DB_Refresh() is pushed into DispData and the screen re-paints automatically.

DispData.Clear();
for( i, 0, rows-1 )
{
   array row = DB["local"].GetRowArray(i);
   DispData.Add($"{row[0]},{row[1]},{row[2]},{row[3]},{row[4]},{row[5]},{row[6]},{row[7]}");
}

2) ModifyDlg — Dialog with Two-way Binding

ModifyDlg is a screen whose ViewModule type is Dialog.

8 edit fields

The variables declared in Data.xms are bound 1:1 to the dialog's input controls.

// Data.xms excerpt
int    EditId        = 0;        // PK (read-only display)
string EditOrderNo   = "";
string EditMenuName  = "";
string EditStartTime = "";       // read-only display
string EditEndTime   = "";
double EditWeightG   = 0.0;
string EditResult    = "";
int    EditIsError   = 0;

If you set the DataName property of each XTextBox / XNumberBox / XCheckBox in the dialog to these variable names, user input is automatically written back into Data::Edit*.

Dialog control	DataName	Recommend readonly
Id display	`Data::EditId`	✓
Order No input	`Data::EditOrderNo`
Menu input	`Data::EditMenuName`
Start time	`Data::EditStartTime`	✓
End time	`Data::EditEndTime`
Weight (g)	`Data::EditWeightG`
Result	`Data::EditResult`
Error checkbox	`Data::EditIsError`

Calling the dialog

DB_OpenModifyDlg(), called by the Modify button, shows the canonical pattern.

FUNCTION DB_OpenModifyDlg()
{
   // (guards omitted)
 
   // 1) Copy selected row values into edit fields
   EditId        = DB["local"].GetValueInt(SelectIndex, "id");
   EditOrderNo   = DB["local"].GetValue   (SelectIndex, "order_no");
   EditMenuName  = DB["local"].GetValue   (SelectIndex, "menu_name");
   EditStartTime = DB["local"].GetValue   (SelectIndex, "start_time");
   EditEndTime   = DB["local"].GetValue   (SelectIndex, "end_time");
   EditWeightG   = DB["local"].GetValueDouble(SelectIndex, "weight_g");
   EditResult    = DB["local"].GetValue   (SelectIndex, "result");
   EditIsError   = DB["local"].GetValueInt(SelectIndex, "is_error");
 
   // 2) Show dialog — blocks until user clicks OK / Cancel
   if( GUI.ShowDialog(/*viewModuleName*/"ModifyDlg") == false )
   {
      Log($"DB_OpenModifyDlg : cancelled by user");
      return false;
   }
 
   // 3) On OK, UPDATE with the edited values
   return DB_UpdateModified();
}

Three crisply separated steps:

DB → Edit fields copy (before showing the dialog)
GUI.ShowDialog — true (OK) / false (Cancel)
Edit fields → DB UPDATE (DB_UpdateModified)

`GUI.ShowDialog` OK / Cancel

The two dialog buttons each carry a DialogResult property.

Button	DialogResult	Effect
OK	`true`	`ShowDialog` returns `true` and the dialog closes
Cancel	`false`	`ShowDialog` returns `false` and the dialog closes

This one-line agreement keeps the calling code simple.

3) Status Label — DbStatusText

Data.xms declares one plain string:

string DbStatusText = "● CLOSED";

If ViewRun's top-right XLabel has its DataName set to Data::DbStatusText, simply switching the value to "● OPEN" in DB_Open() and "● CLOSED" in DB_Close() makes the screen track automatically.

Summary — "Update data and the screen follows"

Variable	Control property	Effect
`DispData` (array string)	`XDataGrid.ItemsSourceDataName`	DataGrid rows
`SelectIndex` (int)	`XDataGrid.SelectIndexDataName`	Selected row 0..N-1 / -1
`Edit*` (8 of them)	Dialog control `DataName`	ModifyDlg two-way
`DbStatusText` (string)	`XLabel.DataName`	Status text

The script just touches variables — that's it. This is QMachineStudio's data-first GUI paradigm. The next chapter ties everything together with events (button clicks).