McBasic™Get McBasic™ ↗
Build 881
Hands-on tutorial · Media & graphics

Show bounded progress

Update determinate progress without exceeding its range.

1 Form / control designs1 complete BASIC filesGuided sample project

A progress bar should measure work, not merely animate while nothing happens. This sample’s Advance action makes the range visible. When the total work is unknown, use an indeterminate state instead of inventing a percentage.

Step 1Prepare a safe practice project#

Extract the archive into a new writable folder, separate from your own application. Open ProgressBar.mcbproj in McBasic™. Keep every declared source, layout, resource and migration file together.

To reconstruct it yourself, create a DesktopApp project and add the files declared below. In the complete project, follow these steps as a guided rebuild: replace each named source file once and Check after all its procedures are present.

Exact project configuration
project.mcproj
{
  "schemaVersion": 1,
  "projectId": "9dbfd264-d29d-47f6-b353-684ce8a3465b",
  "name": "ProgressBarSample",
  "kind": "DesktopApp",
  "ai": {
    "storeChatsInProject": false
  },
  "language": {
    "dialect": "McBasic1",
    "requireExplicit": true,
    "compare": "Binary",
    "defaultArrayBase": 0
  },
  "application": {
    "bundleIdentifier": "com.mcbasic.samples.progressbar",
    "version": "0.1.0",
    "buildNumber": "1",
    "startupFormId": "form-main",
    "shutdownMode": "OnStartupFormClosed"
  },
  "forms": [
    {
      "id": "form-main",
      "typeName": "frmMain",
      "layout": "Forms/frmMain.form.json",
      "code": "Forms/frmMain.bas"
    }
  ],
  "modules": [],
  "classes": [],
  "tests": [],
  "references": [],
  "resources": [],
  "targets": [
    "osx-arm64"
  ],
  "capabilities": []
}

Step 2Build the Form and set its properties#

frmMain

Select the Form first and set its properties. Add containers before their children. These are initial Designer values, not statements to paste into a procedure.

Form propertyValue
Caption"ProgressBar — McBasic"
Width540
Height260
MinWidth420
MinHeight220
TypeNameParent
ProgressBarpgbProgressForm
LabellblStatusForm
CommandButtoncmdAdvanceForm
CommandButtoncmdCloseForm
pgbProgress · exact Inspector values
PropertyValue
Left44
Top64
Width28
Height120
Minimum0
Maximum100
Value25
IndeterminateFalse
Orientation"Vertical"
TabIndex0
Anchor edgesLeft, Top
lblStatus · exact Inspector values
PropertyValue
Left100
Top64
Width384
Height32
Caption"Progress: 25%"
Anchor edgesLeft, Top
cmdAdvance · exact Inspector values
PropertyValue
Left44
Top168
Width160
Height36
Caption"Advance"
TabIndex1
Anchor edgesLeft, Top
cmdClose · exact Inspector values
PropertyValue
Left324
Top168
Width160
Height36
Caption"Close"
TabIndex2
Anchor edgesLeft, Top

Step 3Connect the events explicitly#

frmMain

ObjectEventProcedureParameters
cmdAdvanceClickcmdAdvance_ClickClick()
cmdCloseClickcmdClose_ClickClick()
FormLoadForm_Load()

Step 4Enter the complete behavior#

Open the named source file. Enter declarations first, then every procedure. Expand a procedure for its full body, or copy the complete file. Helpers are required: do not stop after entering the first Click handler.

Forms/frmMain.bas

Enter these declarations at file scope, before the procedures.

Forms/frmMain.bas · declarations
Option Explicit
Private Sub Form_Load()

Initialize state before enabling dependent actions. Keep the shared declarations and startup dependencies with this procedure.

Forms/frmMain.bas · Form_Load
Private Sub Form_Load()
    pgbProgress.Minimum = 0
    pgbProgress.Indeterminate = False
    pgbProgress.Orientation = "Vertical"
    lblStatus.Caption = pgbProgress.Orientation & " progress: " & pgbProgress.Value & "/" & pgbProgress.Maximum
End Sub
Private Sub cmdAdvance_Click()

Enter the complete action, including its input checks and calls to helper procedures.

Forms/frmMain.bas · cmdAdvance_Click
Private Sub cmdAdvance_Click()
    If pgbProgress.Value < pgbProgress.Maximum Then
        pgbProgress.Value = pgbProgress.Value + 10
    End If
    lblStatus.Caption = "Progress: " & pgbProgress.Value & "%"
End Sub
Private Sub cmdClose_Click()

Enter the complete action, including its input checks and calls to helper procedures.

Forms/frmMain.bas · cmdClose_Click
Private Sub cmdClose_Click()
    Unload Me
End Sub
Copy the complete Forms/frmMain.bas file

Replace the file once; do not append duplicate procedures.

Forms/frmMain.bas
Option Explicit

Private Sub Form_Load()
    pgbProgress.Minimum = 0
    pgbProgress.Indeterminate = False
    pgbProgress.Orientation = "Vertical"
    lblStatus.Caption = pgbProgress.Orientation & " progress: " & pgbProgress.Value & "/" & pgbProgress.Maximum
End Sub

Private Sub cmdAdvance_Click()
    If pgbProgress.Value < pgbProgress.Maximum Then
        pgbProgress.Value = pgbProgress.Value + 10
    End If
    lblStatus.Caption = "Progress: " & pgbProgress.Value & "%"
End Sub

Private Sub cmdClose_Click()
    Unload Me
End Sub

Step 5Keep resources and storage reproducible#

No external resource or migration files are declared. Any inline migration, seed data or local JSON is present in the code above. Runtime application data and private preferences are not included in the archive.

Step 6Check, run and test the result#

Save all files and run Check. Resolve diagnostics before Run. Developer CLI users can work from the extracted folder:

Developer CLI
mcbasic check ProgressBar.mcbproj
mcbasic run ProgressBar.mcbproj

Acceptance checklist

  • Advance repeatedly through the configured range.
  • Verify the displayed value and bar agree.
  • Test the maximum boundary.

Step 7Make one change and repeat the tests#

Reset the progress and add an indeterminate mode for a separate unknown-duration operation.

Save a working Git checkpoint first. Change one behavior, Check again and repeat the acceptance checklist. Compare with the downloaded solution if a regression appears.

Source baseline 20f4bfed6b · Build manifest