復選框是選擇各種不同選項的最常用控件之壹。用戶可選中或取消選中復選框,並且可壹次選中任意個框。使用鍵盤界面時,被聚焦的復選框的狀態可使用<SPACE>鍵切換。禁用的框顯示為灰色,如下圖所示,其中描述了每種可能的復選框的外觀:
開啟皮膚色後顯示效果如下:
41.2 官方WIDGET_CheckBox實例
官方的這個例子做的很好,充分的演示了復選框的各個狀態。這個例子在模擬器中的位置:
41.2 源代碼如下(主要看WIDGET_Checkbox中的代碼):
#include <stddef.h>
#include "GUI.h"
#include "DIALOG.h"
#include "Main.h"
/*********************************************************************
*
* Static data
*
**********************************************************************
*/
//
// Dialog resource
//
static const GUI_WIDGET_CREATE_INFO _aDialogCreate[] = {(1)
{ FRAMEWIN_CreateIndirect, "Check box sample", 0, 10, 10, 300, 220, FRAMEWIN_CF_MOVEABLE},
{ TEXT_CreateIndirect, "Enabled:", 0, 5, 10, 120, 0 },
{ CHECKBOX_CreateIndirect, 0, GUI_ID_CHECK0, 5, 30, 120, 0 },
{ CHECKBOX_CreateIndirect, 0, GUI_ID_CHECK1, 5, 60, 120, 0 },
{ CHECKBOX_CreateIndirect, 0, GUI_ID_CHECK2, 5, 90, 120, 20 },
{ CHECKBOX_CreateIndirect, 0, GUI_ID_CHECK3, 5, 125, 120, 26 },
{ TEXT_CreateIndirect, "Disabled:", 0, 150, 10, 120, 0 },
{ CHECKBOX_CreateIndirect, 0, GUI_ID_CHECK4, 150, 30, 120, 0 },
{ CHECKBOX_CreateIndirect, 0, GUI_ID_CHECK5, 150, 60, 120, 0 },
{ CHECKBOX_CreateIndirect, 0, GUI_ID_CHECK6, 150, 90, 120, 26 },
{ CHECKBOX_CreateIndirect, 0, GUI_ID_CHECK7, 150, 125, 120, 26 },
{ BUTTON_CreateIndirect, "OK", GUI_ID_OK, 10, 170, 60, 20 },
{ BUTTON_CreateIndirect, "Cancel", GUI_ID_CANCEL, 225, 170, 60, 20 },
};
//
// Check box text
//
static const char * _apLabel[] = {(2)
"Default",
"3 States",
"Box XL",
"Box XXL"
};
/*********************************************************************
*
* Static code
*
**********************************************************************
*/
/*********************************************************************
*
* _cbCallback
*/
static void _cbCallback(WM_MESSAGE * pMsg) {
WM_HWIN hDlg;
WM_HWIN hItem;
int i;
int NCode;
int Id;
hDlg = pMsg->hWin;
switch (pMsg->MsgId) {
case WM_INIT_DIALOG:
WM_GetDialogItem(hDlg, GUI_ID_CHECK0);
for (i = 0; i < 8; i++) {(3)
int Index = i % 4;
hItem = WM_GetDialogItem(hDlg, GUI_ID_CHECK0 + i); // Get the handle of the desired checkbox
CHECKBOX_SetText(hItem, _apLabel[Index]); // Set the check box text(4)
switch (Index) {
case 1:(5)
//
// Set the number of possible states to 3
//
CHECKBOX_SetNumStates(hItem, 3);(6)
//
// Use user defined bitmaps for the third state
//(7)
CHECKBOX_SetImage(hItem, &_abmBar[0], CHECKBOX_BI_INACTIV_3STATE); // Used if widget is disabled
CHECKBOX_SetImage(hItem, &_abmBar[1], CHECKBOX_BI_ACTIV_3STATE); // Used if widget is enabled
CHECKBOX_SetState(hItem, 2);(8)
break;
case 2:(9)
CHECKBOX_SetState(hItem, 1);
//
// Use user defined bitmaps for the 'checked' state
//
CHECKBOX_SetImage(hItem, &_abmXL[0], CHECKBOX_BI_INACTIV_CHECKED); // Used if widget is disabled
CHECKBOX_SetImage(hItem, &_abmXL[1], CHECKBOX_BI_ACTIV_CHECKED); // Used if widget is enabled?
CHECKBOX_SetFont(hItem, &GUI_FontComic18B_ASCII);
break;
case 3:(10)
CHECKBOX_SetState(hItem, 1);
//
// Use user defined bitmaps for the 'checked' state
//
CHECKBOX_SetImage(hItem, &_abmXXL[0], CHECKBOX_BI_INACTIV_CHECKED); // Used if widget is disabled
CHECKBOX_SetImage(hItem, &_abmXXL[1], CHECKBOX_BI_ACTIV_CHECKED); // Used if widget is enabled?
CHECKBOX_SetFont(hItem, &GUI_FontComic24B_ASCII);
break;
}
//
// Disable all check boxes shown on the right side of the dialog
//
if (i >= 4) {(11)
WM_DisableWindow(hItem);
}
}
break;
case WM_NOTIFY_PARENT:
Id = WM_GetId(pMsg->hWinSrc); // Id of widget
NCode = pMsg->Data.v; // Notification code
switch (NCode) {
case WM_NOTIFICATION_RELEASED: // React only if released
if (Id == GUI_ID_OK) { // OK Button
GUI_EndDialog(hDlg, 0);
}
if (Id == GUI_ID_CANCEL) { // Cancel Button
GUI_EndDialog(hDlg, 1);
}
break;
}
break;
default:
WM_DefaultProc(pMsg);
}
}
/*********************************************************************
*
* Public code
*
**********************************************************************
*/
/*********************************************************************
*
* MainTask
*/
void MainTask(void) {
#if GUI_SUPPORT_MEMDEV
WM_SetCreateFlags(WM_CF_MEMDEV);
#endif
GUI_Init();
WM_SetDesktopColor(GUI_BLACK);
while (1) {
GUI_ExecDialogBox(_aDialogCreate, GUI_COUNTOF(_aDialogCreate), &_cbCallback, 0, 0, 0);
GUI_Delay(500);
}
}
41.1.1 復選框支持的通知代碼
以下事件是復選框控件作為WM_NOTIFY_PARENT消息的壹部分發送給其父窗口的:
消息 描述?
WM_NOTIFICATION_CLICKED 復選框已被點擊。?
WM_NOTIFICATION_RELEASED 復選框已被釋放。?
WM_NOTIFICATION_MOVED_OUT 復選框已被點擊,且指針已移出復選框並且沒有釋放。?
WM_NOTIFICATION_VALUE_CHANGED 復選框的狀態已改變。?
41.1.2 按鈕支持鍵盤反應
如果控件具有輸入焦點,則它將對下列各鍵做出反應:
按鍵 反應?
GUI_KEY_SPACE 切換小工具的選中狀態