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6 - Displaying The Keyboards
Our sample app also includes a special response to the K_KEYBOARD value, to provide an onscreen keyboard: if ( K_KEYBOARD==data || ( hostIO_is_simulator() && 'k'==data ) )
{
static bool inUse=false;
if ( ! inUse )
{
inUse=true; // lock & prevent second call
CLatin1Keyboard *keyboard=new CLatin1Keyboard(99,0);
keyboard->SetCurScreen(0); // choose keyboard
GUI_EventLoop(keyboard); // display it
inUse=false; // unlock
}
}
The first line checks for the keyboard code.
As a convenient shortcut in debugging (and
because I couldn't find a way to generate
the K_KEYBOARD key on the simulator), the
code also allows the 'k' character to call
it up (using hostIO_is_simulator() to guarantee
this shortcut only works on the emulator,
and won't interfere with code running on
a real ebm).Once we've decided that it's Keyboard Time, we then prepare to display. The inUse static variable is needed because of a bug my code encountered: when I displayed the keyboard with the upward stroke, doing so a second time crashed the program. While unlikely in general use, the extra code makes sure this can't happen, since the inUse variable acts as an access lock to prevent multiple simultaneous calls of the keyboard.
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