simplecalc.c

uclinux 下的一个计算器程序

    switch (action) {
        case NUM0:
            if (position == 0) {
                updateDisplay();
                break;
            }
        case NUM1 ... NUM9:
            emtk_label_hide(exponent_id);
            insertChar(action - NUM0 + '0');
            current_register->value = getDouble();
            updateDisplay();
            break;
        case ADD:
            temp = current_register->value;
            if (stack_length(stack) > 1) {
                setDisplay(evaluate());
                updateDisplay();
            }
            current_register->op = OP_ADD;
            current_register = register_new();
            current_register->value = temp;
            stack_push(stack, current_register);
            clearBuffer();
            break;
        case SUB:
            temp = current_register->value;
            if (stack_length(stack) > 1) {
                setDisplay(evaluate());
                updateDisplay();
            }
            current_register->op = OP_SUB;
            current_register = register_new();
            current_register->value = temp;
            stack_push(stack, current_register);
            clearBuffer();
            break;
        case MUL:
            current_register->op = OP_MUL;
            current_register = register_new();
            stack_push(stack, current_register);
            clearBuffer();
            break;
        case DIV:
            current_register->op = OP_DIV;
            current_register = register_new();
            stack_push(stack, current_register);
            clearBuffer();
            break;
        case SQRT:
            current_register->value = sqrt(current_register->value);
            setDisplay(current_register->value);
            updateDisplay();
            clearBuffer();
            break;
        case SIGN:
            current_register->value *= -1;
            if (position > 0) {
                if (current_register->value >= 0)
                    position--;
                else
                    position++;
            } else {
                position = 1;
            }
                
            setDisplay(current_register->value);
            updateDisplay();
            break;
        case PERCENT:
            current_register->value = current_register->value / 100;
            setDisplay(current_register->value);
            updateDisplay();
            clearBuffer();
            break;
        case EQ:
            setDisplay(evaluate());
            updateDisplay();
            clearBuffer();
            position = 0;
            break;
        case ALLCLEAR:
            all_clear();
            clearBuffer();
            updateDisplay();
            break;
        case CLEAR:
            current_register->value = 0;
            clearBuffer();
            updateDisplay();
            break;
        case DOT:
            if (!decimal) {
                if (position == 0) {
                    insertChar('0');
                }
                insertChar('.');
                decimal = TRUE;
            }
            updateDisplay();
            break;
        case MEMADD:
            memory += current_register->value;
            if (memory != 0.0)
                emtk_label_show(memory_id);
            else
                emtk_label_hide(memory_id);
            
            break;
        case MEMSUB:
            memory -= current_register->value;
            if (memory != 0.0)
                emtk_label_show(memory_id);
            else
                emtk_label_hide(memory_id);
            
            break;
        case MEMCLEAR:
            memory = 0.0;
            emtk_label_hide(memory_id);
            break;
        case MEMRELEASE:
            current_register->value = memory;
            setDisplay(memory);
            updateDisplay();
            break;
        case BACK:
            if (position > 1) {
                buffer[--position] = '\0';
            } else if (position == 1) {
                position--;
                buffer[0] = '0';
                buffer[1] = '.';
            }
            updateDisplay();
            current_register->value = getDouble();
            break;
    }
}

static void drawWnd(int wid, WindowRect *rect) {
    int i;
    
    int ascent, descent;
    int font, small_fn, width;
    
    font        = lookupFont("en_US", LARGE_FONT);
    small_fn    = lookupFont("en_US", SMALL_FONT);
    
    for (i = 0; buttondefs[i].on != NULL; i++) {
        
#ifdef TEXT_ONLY_BUTTON
        buttons[i] = emtk_button_new(wid, 
            COL(buttondefs[i].col), ROW(buttondefs[i].row), 
            buttondefs[i].w, buttondefs[i].h,
            font, buttondefs[i].str, buttondefs[i].key, btnHandler, (void *) buttondefs[i].action);
            
        emtk_button_set_border_width(buttons[i], 1);
#else
        buttons[i] = emtk_button_new(wid, 
            COL(buttondefs[i].col), ROW(buttondefs[i].row), 
            buttondefs[i].w, buttondefs[i].h,
            font, "", buttondefs[i].key, btnHandler, (void *) buttondefs[i].action);

        emtk_button_set_pixmap(buttons[i], buttondefs[i].on, buttondefs[i].off, FALSE);
        
        emtk_button_set_border_width(buttons[i], 0);
#endif
        emtk_window_add_object(wid, buttons[i]);
    }
    
    emtk_get_font_height(font, &ascent, &descent);
    
    display_id  = emtk_label_new(wid, 20, ascent+descent+2, font, 
									FALSE, NULL_DISPLAY);
    
    width = emtk_string_display_length("8888888888888.", font) + 23;
    
    exponent_id = emtk_label_new(wid, width, 18, small_fn, FALSE, "");
    memory_id   = emtk_label_new(wid, 5,     18, small_fn, FALSE, "M");
    
    emtk_window_add_object(wid, display_id);
    emtk_window_add_object(wid, exponent_id);
    emtk_window_add_object(wid, memory_id);
    emtk_label_hide(memory_id);
    
}

#ifdef MERGE_EMTK_LAUNCHER
extern void launcher_app_close_callback();
#endif

static void closeHandler(int window, void *data) {
	int *feedback = (int *) data;
	*feedback = EMTK_APP_WINDOW_DESTROY_WITH_EMTK_CLOSE;

    stack_free(stack);
	
    //emtk_app_close();
    
#ifdef MERGE_EMTK_LAUNCHER
	emtk_app_close_window(app_window);
	launcher_app_close_callback();
#else
	//emtk_app_close();
#endif /* MERGE_EMTK_LAUNCHER */
}

static void init() {
    app_window = emtk_app_window_new(_("Calculator"), FONT2, drawWnd, closeHandler, NULL);
    
    position = 0;
    memory = 0.0;
    stack = stack_new();
    current_register = register_new();
    stack_push(stack, current_register);
}

#ifdef LAUNCHER_SUPPORT
static void simplecalc_desktop_msg(MSG *mesg, gpointer user_data) {
    g_return_if_fail(mesg != NULL);
    
    if (mesg->type == MSG_TYPE_COMMAND && mesg->subtype == MSG_COMMAND_CLOSE) {
        emtk_app_close_window(app_window);
    }
}
#endif /* LAUNCHER_SUPPORT */

#ifdef MERGE_EMTK_LAUNCHER
int simpcalc_main(int argc, char **argv)
#else
int main(int argc, char **argv)
#endif /* MERGE_EMTK_LAUNCHER */
{
#if !defined(MERGE_EMTK_LAUNCHER)

#ifdef LAUNCHER_SUPPORT
    DESKTOP_CHANNEL channel;
    
    if (!desktop_channel_listen_connect(&channel, simplecalc_desktop_msg, NULL)) {
        printf("Error opening listening channel\n");
        return 1;
    }
#endif /* LAUNCHER_SUPPORT */

    init_font_table(NULL);

    i18n_init();
    
    emtk_app_init(&argc, &argv);
    emtk_app_root(APP_X, APP_Y, APP_W, APP_H);
#endif /* !defined(MERGE_EMTK_LAUNCHER) */
    
    init();
    
#if !defined(MERGE_EMTK_LAUNCHER)
    emtk_app_run();
    
    unload_font_table();
    
#ifdef LAUNCHER_SUPPORT
    desktop_channel_listen_disconnect(&channel);
#endif /* LAUNCHER_SUPPORT */
#endif /* !defined(MERGE_EMTK_LAUNCHER) */


    
    return 0;
    
}