Eventos e interactividad - Small Basic

Notas del editor

• #5: Code: Sub keyup If GraphicsWindow.LastKey = return then Shapes.Rotate(shape1, 0) EndIf EndSub Sub keydown If GraphicsWindow.LastKey = return then Shapes.Rotate(shape1, 90) EndIf EndSub
• #6: In the editor window, you add the rectangle by using the AddRectangle operation of the Shapes object. You set the location of the rectangle by using the Move operation. You identify the key with which the rectangle can be rotated. You declare the key and assign it a suitable variable name. You use the KeyDown event of the GraphicsWindow object and declare a subroutine to rotate the shape when the user presses the key. Similarly, you use the KeyUp event and declare a subroutine to rotate the shape when the user releases the key. When you click Run on the toolbar, your program runs. A graphics window appears with a rectangle in the center. When you press RETURN, the rectangle rotates. When you release the Return key, the rectangle rotates back to its original position. Code: GraphicsWindow.Height = 300 GraphicsWindow.Width = 300 GraphicsWindow.Title = "Graphics Window" shape1 = Shapes.AddRectangle(100, 50) Shapes.Move(shape1, 100, 125) return = "Return" GraphicsWindow.KeyDown = keydown GraphicsWindow.KeyUp = keyup Sub keydown If GraphicsWindow.LastKey = return then Shapes.Rotate(shape1, 90) EndIf EndSub Sub keyup If GraphicsWindow.LastKey = return then Shapes.Rotate(shape1, 0) EndIf EndSub
• #7: You must declare the mouse events in your code. Small Basic has three types of mouse events: MouseDown, MouseUp, and MouseMove. You must also assign an accompanying subroutine for your event. When the mouse is clicked, released, or moved, the subroutine will perform the action that is defined within it. You can use mouse events on controls and shapes. Code: GraphicsWindow.MouseDown = MouseClick GraphicsWindow.MouseMove = MouseDrag GraphicsWindow.MouseUp = MouseUp Sub MouseClick OrgX = GraphicsWindow.MouseX OrgY = GraphicsWindow.MouseY EndSub Sub MouseDrag x = GraphicsWindow.MouseX y = GraphicsWindow.MouseY If (Mouse.IsLeftButtonDown) then GraphicsWindow.DrawLine(OrgX, OrgY, x, y) Endif EndSub Sub MouseUp GraphicsWindow.PenColor=GraphicsWindow.GetRandomColor() GraphicsWindow.PenWidth=Math.GetRandomNumber(5) EndSub
• #9:  Solution: GraphicsWindow.Hide() w = 620 h = 450 GraphicsWindow.CanResize = "False" GraphicsWindow.Width = w GraphicsWindow.Height = h GraphicsWindow.Top = (Desktop.Height-h) / 2 GraphicsWindow.Left = (Desktop.Width-w) / 2 GraphicsWindow.Show() GraphicsWindow.Title = "Events and interactivity" GUI() Controls.ButtonClicked = MouseAction Sub GUI GraphicsWindow.DrawRectangle(10, 10, 600, 320) GraphicsWindow.DrawRectangle(10, 340, 200, 100) GraphicsWindow.DrawRectangle(10, 340, 600, 100) GraphicsWindow.DrawRectangle(370, 340, 150, 100) Triangle = Controls.AddButton("Triangle", 40, 345) Controls.SetSize(Triangle, 120, 30) Rectangle = Controls.AddButton("Rectangle",40,375) Controls.SetSize(Rectangle, 120, 30) Circle = Controls.AddButton("Circle", 40, 405) Controls.SetSize(Circle, 120, 30) Rotate = Controls.AddButton("Rotate", 230, 360) Controls.SetSize(Rotate, 60, 60) Zoom = Controls.AddButton("Zoom", 290, 360) Controls.SetSize(Zoom, 60, 60) FreeHand = Controls.AddButton("Draw", 390, 360) Controls.SetSize(FreeHand, 60, 60) Clear = Controls.AddButton("Clear", 450, 360) Controls.SetSize(Clear, 60, 60) Exit = Controls.AddButton("Exit", 530, 360) Controls.SetSize(Exit, 60, 60) EndSub Sub MouseAction x = GraphicsWindow.MouseX y = GraphicsWindow.MouseY GraphicsWindow.PenWidth = 1 If x > 40 And x < 160 Then GraphicsWindow.BrushColor = GraphicsWindow.GetRandomColor() If y > 345 And y < 375 Then draw = 0 j = 0 z = 1 tri = Shapes.AddTriangle(20, 20, 100, 100, 150, 20) Shapes.Move(tri, 80, 100) EndIf If y > 375 And y < 405 Then draw = 0 j = 0 z = 2 rect = Shapes.AddRectangle(100, 100) Shapes.Move(rect, 250, 150) EndIf If y > 405 And y < 435 Then draw = 0 j = 0 z = 3 circ = Shapes.AddEllipse(100, 100) Shapes.Move(circ, 400, 150) EndIf EndIf If y > 360 And y < 420 Then If x > 230 And x < 290 Then draw = 0 If z = 1 Then Shapes.Rotate(tri, 30 + m) Else If z = 2 Then Shapes.Rotate(rect,30 + m) Else If z = 3 Then Shapes.Rotate(circ, 30 + m) Endif Endif Endif m = m + 30 EndIf If x > 290 And x < 390 Then draw = 0 i = 0.1 + j If i < 0.4 Then If z = 1 Then Shapes.Zoom(tri, 1 + i, 1 + i) Else If z = 2 Then Shapes.Zoom(rect, 1 + i, 1 + i) Else If z = 3 Then Shapes.Zoom(circ, 1 + i, 1 + i) EndIf EndIf EndIf j = j + 0.1 EndIf EndIf If x > 390 And x < 450 Then draw = 1 Paint() EndIf If x > 450 And x < 510 Then draw = 0 j = 0 GraphicsWindow.Clear() GraphicsWindow.BrushColor = "Blue" GUI() draw = 0 EndIf If x > 530 And x < 590 Then draw = 0 Program.End() EndIf EndIf EndSub Sub Paint If draw = 1 Then GraphicsWindow.MouseMove = MouseDrag Else If Mouse.IsLeftButtonDown Then MouseAction() EndIf EndIf EndSub Sub MouseDrag If draw = 1 then x = GraphicsWindow.MouseX y = GraphicsWindow.MouseY If x > 10 And x < 600 And y > 10 And y < 320 Then If Mouse.IsLeftButtonDown Then GraphicsWindow.DrawLine(OrgX, OrgY, x, y) EndIf EndIf OrgX = x OrgY = y EndIf EndSub