I'm trying to write a calculator program and would like to know
how to get pushbuttons to react to a key pressed. So if I press '1' the button would change. Does this require a Accelerator Table?
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I'm trying to write a calculator program and would like to know
how to get pushbuttons to react to a key pressed. So if I press '1' the button would change. Does this require a Accelerator Table?
This is very old and probably bug-ridden (you're just dying to use it then, right? :D ). If nothing else works, give it a shot....
[code]
char ParamsToChar(WPARAM wParam, LPARAM lParam, bool *shift_on, bool *caps_on)
{
char found = 0;
int key = LOWORD(wParam);
int value[50] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 26, 27, 28, 29, 39, 40, 41, 42, 43, 51, 52, 53, 55, 57, 58, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 284, 285, 309, 328, 331, 333, 336 };
char unshiftTable[50] = { VK_ESCAPE, '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '-', '=', VK_BACK, VK_TAB, '[',']',VK_RETURN, VK_CONTROL, ';','\'','`',VK_SHIFT, '\\', ',','.','/','*', ' ', VK_CAPITAL, '7', '8','9','-','4','5','6','+','1','2','3','0','.', VK_RETURN, VK_CONTROL, '/', VK_UP, VK_LEFT, VK_RIGHT, VK_DOWN };
char shiftTable[50] = { VK_ESCAPE, '!', '@', '#', '$', '%', '^', '&', '*', '(', ')', '_', '+', VK_BACK, VK_TAB, '{','}',VK_RETURN, VK_CONTROL, ':','"' ,'~',VK_SHIFT, '|', '<','>','?','*', ' ', VK_CAPITAL, '7', '7','9','-','4','5','6','+','1','2','3','0','.', VK_RETURN, VK_CONTROL, '/', VK_UP, VK_LEFT, VK_RIGHT, VK_DOWN };
char *table = (*shift_on) ? shiftTable : unshiftTable; //...unused if we find an alphabetical...
if(isalpha(LOWORD(wParam)) && HIWORD(lParam) < 55)
{
if(*shift_on || *caps_on)
found = key;
else
found = tolower(key);
}
if(*shift_on) *shift_on = false; //...shift key expires...
if(!found)
{
key = HIWORD(lParam);
int code;
for(code = 0; code < 50; code++)
{
if(value[code] == key) found = tableCode:;
}
if(found == VK_SHIFT)
*shift_on = true; //...shift key is reactivated...
else
if(found == VK_CAPITAL)
*caps_on = !(*caps_on);
}
return found; //...could be !found, of course...
}
The simplest solution to your problem would be to use hotkeys in your program to detect if somebody pressed '1', '2', etc.
This is acheived through the use of a funky function called RegisterHotKey(). Once you've registered the hotkey, you simply check for the WM_HOTKEY message in your window/dialog callback function, check the wParam for which hotkey was pressed and handle it appropriately. Here's a commented sample, fresh from the oven:
Alright, that's pretty messy code, but hopefully it should convey some idea.Code:// First, define a hotkey ID to make life easier
#define ID_HOTKEY_1 (WM_USER+1)
...
// Now in some function (e.g. when you handle the WM_INITDIALOG message in a dialog procedure), declare this:
BOOL bSuccess = RegisterHotKey(hWnd, ID_HOTKEY_1, NULL, VK_1);
// Check if it worked
if(!bSuccess)
{
MessageBox(hWnd, "Hotkey failed.", "Error", MB_OK);
return TRUE;
}
...
// Now in your CALLBACK function, you could handle something like:
case WM_HOTKEY:
// First check if our window is active
if(hWnd != GetForegroundWindow()) return TRUE;
// If it is, continue
switch(wParam)
{
case ID_HOTKEY_1:
SendDlgItemMessage(hWnd, IDC_BUTTON_1, WM_LBUTTONUP, 0, 0);
break;
// Add more cases to handle other keys
}
break;
If I was certain of how to handle the WM_KEYUP message, I would tell you that instead (it's probably much more appropriate than setting up a hotkey).
So, if you don't want to mess about with hotkeys, look up how to handle the following messages on MSDN or something:
* WM_KEYUP
* WM_KEYDOWN
* WM_CHAR
Hope this helped a little. Sorry for the ambiguity. :(
- Penguin of Oz
Penguin of Oz, I have tried you code and have been able to compile successfully. The problem is on the with:
BOOL bSuccess = RegisterHotKey(hWnd, ID_HOTKEY_1, NULL, VK_1);
What's the last paramter suppose to be? A ascii value?
It's supposed to be the virtual keycode for the character '1'. Sorry, I didn't test this code... :x
I'll try and find the VKCode for 1 now... one moment...
Turns out you can use ASCII values there too, so replace the VK_1 with 49.
49 or VK_1 will be the 1 right above the Q, for the numpad, use VK_NUMPAD1
if you are using MSVC++ all you have to do is, in the caption for the button put something like F&our, and it will look like this Four, and when o is pressed it presses the button,all u have to do is put & in front of the character that u want the 'hotkey' to be, make sure to 'check neumonics' somewhere in the menus,cant remember where
MOst likely, he wants a 4 on the button, not "Four"
-Futura
well holy crap-lol not that much different, just put &4 what was the point of your post?
OK, so you have an underlined 4, not too bad, but I would definitely go with hotkeys or monitoring the WM_KEYDOWN message. I'd be a cleaner solution. Also the mnemonics only work in dialog boxes, not regular windows.
-Futura
im pretty sure a calculator is going to be made in a dialog, and the nmeunoics would do perfectly fine with that, i mean, why would it be in a normal window? anyways...
Well, I'm going to use Cgawd's solution for now. Maybe after I get the program fully written I'll try some of the other solutions.
When I compile using the Borland commandline compiler it says VK_1 is undefined. Shouldn't Borland be able to compile it as VK_1 instead of 49?Quote:
49 or VK_1 will be the 1 right above the Q, for the numpad, use VK_NUMPAD1
>>Shouldn't Borland be able to compile it as VK_1<<
Only if you have defined them. Msvc doesn't. From winuser.h:
So you could either use these values or #define the virtual key codes yourself.Quote:
/*
* VK_0 - VK_9 are the same as ASCII '0' - '9' (0x30 - 0x39)
* 0x40 : unassigned
* VK_A - VK_Z are the same as ASCII 'A' - 'Z' (0x41 - 0x5A)
*/