The mouse & The keyboard

On-screen keyboard

• Demonstration
• Functionality:
  • On-screen keyboard
    • Only keys corresponding to letters 'A' - 'Z' are included
    • Keys layout is similar to QWERTY keyboards
      • 3 rows
      • the 1st row fills the screen horizontally
      • the 2nd row is shifted right about half of the key's size
      • the 3rd row is shifted right about key's size
    • All keys are square and have the same size
    • Key spacing is 2px
    • The on-screen keyboard is vertically centered
    • All keys have blue background color and have a default transparency level set to 50%
  • Features of the keyboard:
    • Opacity is set when corresponding key is pressed
    • Background color is set to red when mouse cursor is over the key's window
    • Transparency level of the currently pressed keys could be change
      • both "+" keys (on alphanumeric and numeric keyboard) smoothly increase the transparency level, no more up to 80%
      • both "-" keys (on alphanumeric and numeric keyboard) smoothly decrease the transparency level, no less than 20%
      • a new transparency level is applied while +/- key is pressed, opacity is set when key is released
    • Left mouse button double-click on a key's window sets the transparency level to the default value (50%)
    • Only one window is visible on the task bar and in the task switch window (Alt+Tab)
• Hints:
  • SetClassLongPtr(), GCLP_HBRBACKGROUND, InvalidateRect()
  • HBRUSH h1 = CreateSolidBrush(RGB(255,0,0));
    HBRUSH h2 = CreateSolidBrush(RGB(0,0,255));
    //...
    SetClassLongPtr(hWnd, GCLP_HBRBACKGROUND, (LONG_PTR)h1);
    InvalidateRect(hWnd, NULL, TRUE);
• TrackMouseEvent(), TRACKMOUSEEVENT, WM_MOUSELEAVE
• WS_EX_LAYERED, SetLayeredWindowAttributes()
• GetSystemMetrics(), SM_CXSCREEN, SM_CYSCREEN

• Approximate points:
  • windows layout: 3.0
  • increase/decrease transparency level: 2.5
  • default transparency setting (doubleclick): 1.0
  • setting opacity at key pressing: 1.0
  • changing color at mouse enter: 1.0
  • changing color at mouse leave: 1.5

• Links for uploading:
  • Solutions
  • Corrections