albumdb.cpp

Programming.Microsoft.Windows.CE.Dot.NET.3rd.Edition.pdf the chapter 9 example codes.

		// Double click indicates edit
		case NM_DBLCLK:
			PostMessage (hWnd, WM_COMMAND, MAKELPARAM (IDM_EDIT, 0), 0);
			break;

		// Ignore cache hinting for db example.
		case LVN_ODCACHEHINT:
			break;

		case LVN_ODFINDITEM:
			// We should do a reverse lookup here to see if
			// an item exists for the text passed.
			return -1;
		}
	}
	return 0;
}
//----------------------------------------------------------------------
// DoDestroyMain - Process WM_DESTROY message for window.
//
LRESULT DoDestroyMain (HWND hWnd, UINT wMsg, WPARAM wParam, 
					   LPARAM lParam) {
	PostQuitMessage (0);
	return 0;
}
//======================================================================
// Command handler routines
//----------------------------------------------------------------------
// DoMainCommandDelDB - Process Program Delete command.
//
LPARAM DoMainCommandDelDB (HWND hWnd, WORD idItem, HWND hwndCtl, 
						   WORD wNotifyCode) {
	int i, rc;

	i = MessageBox (hWnd, TEXT ("Delete the entire database?"), 
					TEXT ("Delete"), MB_YESNO);
	if (i != IDYES) 
		return 0;
	if (g_oidDB) {
		CloseHandle (g_hDB);
		rc = CeDeleteDatabase (g_oidDB);
		if (rc == 0) {
			ErrBox (hWnd, TEXT ("Couldn\'t delete database. rc=%d"), 
					GetLastError());
			g_hDB = OpenDB (hWnd, NULL);   // Open the database.
			return 0;
		}
		g_hDB = INVALID_HANDLE_VALUE;
		g_oidDB = 0;
	}
	ListView_SetItemCount (GetDlgItem (hWnd, ID_LISTV), 0);
	return 0;
}
//----------------------------------------------------------------------
// DoMainCommandExit - Process Program Exit command.
//
LPARAM DoMainCommandExit (HWND hWnd, WORD idItem, HWND hwndCtl, 
						  WORD wNotifyCode) {
	SendMessage (hWnd, WM_CLOSE, 0, 0);
	return 0;
}
//----------------------------------------------------------------------
// DoMainCommandNew - Process Program New command.
//
LPARAM DoMainCommandNew (HWND hWnd, WORD idItem, HWND hwndCtl, 
						 WORD wNotifyCode) {
	PCEPROPVAL pcepv;
	int i, rc;
	CEOID oid;
	HWND hwndLV = GetDlgItem (hWnd, ID_LISTV);
	// Display the new/edit dialog.
	pcepv = 0;
	rc = DialogBoxParam (hInst, TEXT ("EditAlbumDlg"), hWnd, 
						 EditAlbumDlgProc, (LPARAM)&pcepv);
	if (rc == 0) 
		return 0;

	// Write the record.
	oid = CeWriteRecordProps(g_hDB, 0, NUM_DB_PROPS, pcepv);
	if (!oid) 
		ErrBox (hWnd, TEXT ("Write Rec fail. rc=%d"), GetLastError());
	
	ClearCache ();								// Clear the lv cache.
	i = ListView_GetItemCount (hwndLV) + 1; 	// Increment list view
												// count.
	ListView_SetItemCount (hwndLV, i);
	InvalidateRect (hwndLV, NULL, TRUE);		// Force redraw.
	return 0;
}
//----------------------------------------------------------------------
// DoMainCommandEdit - Process Program Edit command.
//
LPARAM DoMainCommandEdit (HWND hWnd, WORD idItem, HWND hwndCtl, 
						  WORD wNotifyCode) {
	PCEPROPVAL pcepv = 0;
	int nSel, rc;
	WORD wProps = 0;
	DWORD dwRecSize, dwIndex;
	CEOID oid;
	HWND hwndLV = GetDlgItem (hWnd, ID_LISTV);

	nSel = ListView_GetSelectionMark (hwndLV);
	if (nSel == -1) 
		return 0;

	// Seek to the necessary record.
	oid = CeSeekDatabase (g_hDB, CEDB_SEEK_BEGINNING, nSel, &dwIndex);
	if (oid == 0) {
		ErrBox (hWnd, TEXT ("Db item not found. rc=%d"), GetLastError());
		return 0;
	}
	// Read all properties for the record. Have the system
	// allocate the buffer containing the data.
	oid = CeReadRecordPropsEx (g_hDB, CEDB_ALLOWREALLOC, &wProps, NULL,
							   (LPBYTE *)&pcepv, &dwRecSize, 0);
	if (oid == 0) {
		ErrBox (hWnd, TEXT ("Db item not read. rc=%d"), GetLastError());
		return 0;
	}
	// Display the edit dialog.
	rc = DialogBoxParam (hInst, TEXT ("EditAlbumDlg"), hWnd, 
						 EditAlbumDlgProc, (LPARAM)&pcepv);
	if (rc == 0) 
		return 0;

	// Write the record.
	oid = CeWriteRecordProps(g_hDB, oid, NUM_DB_PROPS, pcepv);
	if (!oid) 
		ErrBox (hWnd, TEXT ("Write Rec fail. rc=%d"), GetLastError());

	LocalFree ((LPBYTE)pcepv);
	ClearCache ();								// Clear the lv cache.

	InvalidateRect (hwndLV, NULL, TRUE);		// Force redraw.
	return 0;
}
//----------------------------------------------------------------------
// DoMainCommandDelete - Process Program Delete command.
//
LPARAM DoMainCommandDelete (HWND hWnd, WORD idItem, HWND hwndCtl, 
							WORD wNotifyCode) {
	HWND hwndLV;
	TCHAR szText[64];
	DWORD dwIndex;
	int i, nSel;
	CEOID oid;

	hwndLV = GetDlgItem (hWnd, ID_LISTV);
	nSel = ListView_GetSelectionMark (hwndLV);
	if (nSel != -1) {

		wsprintf (szText, TEXT ("Delete this item?")); 
		i = MessageBox (hWnd, szText, TEXT ("Delete"), MB_YESNO);
		if (i != IDYES) 
			return 0;

		// Seek to the necessary record.
		oid = CeSeekDatabase (g_hDB, CEDB_SEEK_BEGINNING, nSel, &dwIndex);
		CeDeleteRecord (g_hDB, oid);

		// Reduce the list view count by one and force redraw.
		i = ListView_GetItemCount (hwndLV) - 1;
		ListView_SetItemCount (hwndLV, i);
		ClearCache ();							// Clear the lv cache.
		InvalidateRect (hwndLV, NULL, TRUE);
	}
	return 0;
}
//----------------------------------------------------------------------
// DoMainCommandSort - Process the Sort commands.
//
LPARAM DoMainCommandSort(HWND hWnd, WORD idItem, HWND hwndCtl, 
						 WORD wNotifyCode) {
	int nSort;

	switch (idItem) {
	case IDM_SORTNAME:
		nSort = 0;
		break;
	case IDM_SORTARTIST:
		nSort = 1;
		break;
	case IDM_SORTCATEGORY:
		nSort = 2;
		break;
	}
	if (nSort == g_nLastSort)
		return 0;

	ReopenDatabase (hWnd, nSort);	   // Close and reopen the database.
	return 0;
}
//----------------------------------------------------------------------
// DoMainCommandAbout - Process the Help | About menu command.
//
LPARAM DoMainCommandAbout(HWND hWnd, WORD idItem, HWND hwndCtl, 
						  WORD wNotifyCode) {
	// Use DialogBox to create modal dialog.
	DialogBox (hInst, TEXT ("aboutbox"), hWnd, AboutDlgProc);
	return 0;
}
//----------------------------------------------------------------------
// CreateLV - Creates the list view control
//
HWND CreateLV (HWND hWnd, RECT *prect) {
	HWND hwndLV;
	LVCOLUMN lvc;

	// Create album list window.  
	hwndLV = CreateWindowEx (0, WC_LISTVIEW, TEXT (""), 
						 WS_VISIBLE | WS_CHILD | WS_VSCROLL |
						 LVS_OWNERDATA | WS_BORDER | LVS_REPORT, 
						 prect->left, prect->top,
						 prect->right - prect->left,
						 prect->bottom - prect->top,
						 hWnd, (HMENU)ID_LISTV, 
						 hInst, NULL);

	// Add columns.
	if (hwndLV) {
		lvc.mask = LVCF_TEXT | LVCF_WIDTH | LVCF_FMT | LVCF_SUBITEM;
		lvc.fmt = LVCFMT_LEFT;
		lvc.cx = 150;
		lvc.pszText = TEXT ("Name");
		lvc.iSubItem = 0;
		SendMessage (hwndLV, LVM_INSERTCOLUMN, 0, (LPARAM)&lvc);

		lvc.mask |= LVCF_SUBITEM;
		lvc.pszText = TEXT ("Artist");
		lvc.cx = 100;
		lvc.iSubItem = 1;
		SendMessage (hwndLV, LVM_INSERTCOLUMN, 1, (LPARAM)&lvc);

		lvc.mask |= LVCF_SUBITEM;
		lvc.pszText = TEXT ("Category");
		lvc.cx = 100;
		lvc.iSubItem = 2;
		SendMessage (hwndLV, LVM_INSERTCOLUMN, 2, (LPARAM)&lvc);
	}
	return hwndLV;
}
//----------------------------------------------------------------------
// OpenDB - Open database.
//
HANDLE OpenDB (HWND hWnd, LPTSTR lpszName) {
	// Reinitialize the notify request structure.
	cenr.dwSize = sizeof (cenr);
	cenr.hwnd = hWnd;
	cenr.dwFlags = CEDB_EXNOTIFICATION;

	if (lpszName)
		g_oidDB = 0;
	return CeOpenDatabaseEx2 (&g_guidDB, &g_oidDB, lpszName, 
							  &g_diex.rgSortSpecs[g_nLastSort], 
							  0, &cenr);
}
//----------------------------------------------------------------------
// OpenCreateDB - Open database, create if necessary.
//
HANDLE OpenCreateDB (HWND hWnd, int *pnRecords) {
	int rc;
	CEOIDINFO oidinfo;

	g_oidDB = 0;
	g_hDB = OpenDB (hWnd, TEXT ("\\Albums"));
	if (g_hDB == INVALID_HANDLE_VALUE) {
		rc = GetLastError();
		if (rc == ERROR_FILE_NOT_FOUND) {

			g_oidDB = CeCreateDatabaseEx2 (&g_guidDB, &g_diex);
			if (g_oidDB == 0) {
				ErrBox (hWnd, TEXT ("Database create failed. rc=%d"), 
						GetLastError());
				return 0;
			}
			g_hDB = OpenDB (hWnd, NULL);
		}
	} 
	CeOidGetInfo (g_oidDB, &oidinfo);
	*pnRecords = oidinfo.infDatabase.wNumRecords;
	return g_hDB;
}
//----------------------------------------------------------------------
// ClearCache - Clears the one-item cache for the list view control
//
void ClearCache (void) {

	if (g_pLastRecord)
		LocalFree (g_pLastRecord);
	g_pLastRecord = 0;			  
	g_nLastItem = -1;
	return;
}
//----------------------------------------------------------------------
// ReopenDatabase - Closes and reopens the database 
//
void ReopenDatabase (HWND hWnd, int nNewSort) {
	int nCnt; 

	if (nNewSort != -1)
		g_nLastSort = nNewSort;

	if (g_hDB)
		CloseHandle (g_hDB);
	ClearCache ();						  // Clear the lv cache.

	g_hDB = OpenCreateDB (hWnd, &nCnt);

	ListView_SetItemCount (GetDlgItem (hWnd, ID_LISTV), nCnt);
	InvalidateRect (GetDlgItem (hWnd, ID_LISTV), NULL, 0);
	return;
}
//----------------------------------------------------------------------
// Get the album data from the database for the requested lv item.
//
int GetItemData (int nItem, PLVCACHEDATA pcd) {
	static WORD wProps;
	DWORD dwIndex;
	CEOID oid;
	PCEPROPVAL pRecord = NULL;
	DWORD dwRecSize;
	int i;

	// See if the item requested was the previous one. If so,
	// just use the old data.
	if ((nItem == g_nLastItem) && (g_pLastRecord)) 
		pRecord = (PCEPROPVAL)g_pLastRecord;
	else {
		// Seek to the necessary record.
		oid = CeSeekDatabase (g_hDB, CEDB_SEEK_BEGINNING, nItem, &dwIndex);
		if (oid == 0) {
			ErrBox (NULL, TEXT ("Db item not found. rc=%d"), 
					GetLastError());
			return 0;
		}
		// Read all properties for the record.	Have the system
		// allocate the buffer containing the data.
		oid = CeReadRecordProps (g_hDB, CEDB_ALLOWREALLOC, &wProps, NULL,
								 (LPBYTE *)&pRecord, &dwRecSize);
		if (oid == 0) {
			ErrBox (NULL, TEXT ("Db item not read. rc=%d"), 
					GetLastError());
			return 0;
		}
		// Free old record, and save the newly read one.
		if (g_pLastRecord)
			LocalFree (g_pLastRecord);
		g_nLastItem = nItem;
		g_pLastRecord = (LPBYTE)pRecord;

	}
	// Copy the data from the record to the album structure.
	for (i = 0; i < wProps; i++) {
		switch (pRecord->propid) {
		case PID_NAME:
			lstrcpy (pcd->Album.szName, pRecord->val.lpwstr);
			break;
		case PID_ARTIST:
			lstrcpy (pcd->Album.szArtist, pRecord->val.lpwstr);
			break;
		case PID_CATEGORY:
			pcd->Album.sCategory = pRecord->val.iVal;
			break;
		case PID_NUMTRACKS:
			pcd->Album.sNumTracks = pRecord->val.iVal;
			break;
		}
		pRecord++;
	}
	return 1;
}
//----------------------------------------------------------------------
// InsertLV - Add an item to the list view control.