Thread: C++ - Win32 - Finding out selected treeview item

The following is the code I have managed to write so far for my GUI:

Code:

#include "QSDCHub.h"
#include "stdafx.h"

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    switch(msg)
    {
	case WM_NOTIFY:
		switch(LOWORD(wParam))
		{
		case IDC_TVMAIN:
			{
				switch(((LPNMHDR) lParam)->code)
				{
				case NM_CLICK:
					//This is where I am stuck... I would like a conditional statement so if a particular item is selected, it performs a particular function (like showing a dialog that is a child of the main form)
				break;
				}
			}
			break;
		}
		break;
		case WM_CLOSE:
            DestroyWindow(hwnd);
        break;
        case WM_DESTROY:
            PostQuitMessage(0);
        break;
        default:
            return DefWindowProc(hwnd, msg, wParam, lParam);
    }
    return 0;
}

HTREEITEM AddItemToTree(HWND hwndTrV, LPSTR lpszItem, int nLevel)
{ 
    TVITEM tvi; 
    TVINSERTSTRUCT tvins; 
    static HTREEITEM hPrev = (HTREEITEM)TVI_FIRST; 
    static HTREEITEM hPrevRootItem = NULL; 
    static HTREEITEM hPrevLev2Item = NULL; 
    HTREEITEM hti; 

    tvi.mask = TVIF_TEXT | TVIF_IMAGE 
               | TVIF_SELECTEDIMAGE | TVIF_PARAM; 

    tvi.pszText = LPWSTR(lpszItem); 
    tvi.cchTextMax = sizeof(tvi.pszText)/sizeof(tvi.pszText[0]); 

    tvi.lParam = (LPARAM)nLevel; 
    tvins.item = tvi; 
    tvins.hInsertAfter = hPrev; 

    if (nLevel == 1) 
        tvins.hParent = TVI_ROOT; 
    else if (nLevel == 2) 
        tvins.hParent = hPrevRootItem; 
    else 
        tvins.hParent = hPrevLev2Item; 

    hPrev = (HTREEITEM)SendMessage(hwndTrV, 
                                   TVM_INSERTITEM, 
                                   0,
                                   (LPARAM)(LPTVINSERTSTRUCT)&tvins); 

    if (nLevel == 1)
        hPrevRootItem = hPrev; 
    else if (nLevel == 2) 
        hPrevLev2Item = hPrev; 

    if (nLevel > 1)
    { 
        hti = TreeView_GetParent(hwndTrV, hPrev); 
        tvi.mask = TVIF_IMAGE | TVIF_SELECTEDIMAGE; 
        tvi.hItem = hti; 
        TreeView_SetItem(hwndTrV, &tvi); 
    } 

    return hPrev; 
} 

BOOL InitTreeViewImageLists(HWND hwndTV) 
{ 
    return TRUE; 
} 

BOOL InitTreeViewItems(HWND hwndTrV) 
{
    int nLevel;

         AddItemToTree(hwndTrV, LPSTR(TEXT("Main")), 2); 
		 AddItemToTree(hwndTrV, LPSTR(TEXT("Hub Statistics")), -1);
		 AddItemToTree(hwndTrV, LPSTR(TEXT("Appearance")), -1);
		 AddItemToTree(hwndTrV, LPSTR(TEXT("Network")), -1);
		 AddItemToTree(hwndTrV, LPSTR(TEXT("Hublists")), -1);
		 AddItemToTree(hwndTrV, LPSTR(TEXT("Expert Settings")), -1);
		 AddItemToTree(hwndTrV, LPSTR(TEXT("User Settings")), 2);
		 AddItemToTree(hwndTrV, LPSTR(TEXT("Bots")), -1);

		 return TRUE;
} 

HWND CreateTreeView(HWND parent)
{
	HWND hwndTrV;
	RECT rcClient;

	GetClientRect(parent, &rcClient);
	hwndTrV = CreateWindowEx(0, WC_TREEVIEW, TEXT("TV_Menu"), 
		WS_VISIBLE | WS_CHILD | WS_BORDER | TVS_HASLINES, 
		0, 0, 150, rcClient.bottom, parent,
		(HMENU)IDC_TVMAIN, GetModuleHandle(NULL), NULL);
	    
	
	if (!InitTreeViewItems(hwndTrV))
    { 
        DestroyWindow(hwndTrV); 
        return FALSE; 
    }
	return hwndTrV;
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
    LPSTR lpCmdLine, int nCmdShow)
{
    WNDCLASSEX wc;
    HWND hwnd;
    MSG Msg;

    wc.cbSize        = sizeof(WNDCLASSEX);
    wc.style         = 0;
    wc.lpfnWndProc   = WndProc;
    wc.cbClsExtra    = 0;
    wc.cbWndExtra    = 0;
    wc.hInstance     = hInstance;
    wc.hIcon         = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_BLKSRV));
    wc.hCursor       = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
    wc.lpszMenuName  = NULL;
    wc.lpszClassName = TEXT("QSDCHubMain");
    wc.hIconSm       = LoadIcon(wc.hInstance, MAKEINTRESOURCE(IDI_BLKSRV));

    if(!RegisterClassEx(&wc))
    {
        MessageBox(NULL, TEXT("Window Registration Failed!"), TEXT("Error!"),
            MB_ICONEXCLAMATION | MB_OK);
        return 0;
    }

    hwnd = CreateWindowEx(
        WS_EX_CLIENTEDGE,
		TEXT("QSDCHubMain"),
        TEXT("QSDCHub"),
        WS_BORDER | WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, CW_USEDEFAULT, 640, 440,
        NULL, NULL, hInstance, NULL);

	CreateTreeView(hwnd);



    if(hwnd == NULL)
    {
        MessageBox(NULL, TEXT("Window Creation Failed!"), TEXT("Error!"),
            MB_ICONEXCLAMATION | MB_OK);
        return 0;
    }

    ShowWindow(hwnd, nCmdShow);
    UpdateWindow(hwnd);

    while(GetMessage(&Msg, NULL, 0, 0) > 0)
    {
        TranslateMessage(&Msg);
        DispatchMessage(&Msg);
    }
    return Msg.wParam;
}

In WndProc, i have commented exactly where I am stuck. I do not know what to do from here and have tried looking through other places for a solution to this dilemma.

It would also make my life easier if I can find out what the name of the selected treeview node is.

I have solved this problem now. And in case anyone has the same problem, here is how I did it. I am sure there are more elegant ways of coding this, but this is what I came up with:

First, I initialized values on the top of my source that will store addresses to the treeview items:

Code:

static HTREEITEM TVI_MAIN = NULL;
static HTREEITEM TVI_HSTATS = NULL;
static HTREEITEM TVI_APP = NULL;
static HTREEITEM TVI_NTWRK = NULL;
static HTREEITEM TVI_HLST = NULL;
static HTREEITEM TVI_SETEX = NULL;
static HTREEITEM TVI_USET = NULL;
static HTREEITEM TVI_BOTS = NULL;

Then, in AddItemToTree, I specified a pointer to the static value of the item being added's handle:

Code:

HTREEITEM *TrI = NULL;

In the same function, I specified which values to place where:

Code:

	if(lpszItem == "Main") { TrI = &TVI_MAIN; *TrI = hPrev; }
	else if(lpszItem == "Hub Statistics") { TrI = &TVI_HSTATS; *TrI = hPrev; }
	else if(lpszItem == "Appearance") { TrI = &TVI_APP; *TrI = hPrev; }
	else if(lpszItem == "Network") { TrI = &TVI_NTWRK; *TrI = hPrev; }
	else if(lpszItem == "Hublists") { TrI = &TVI_HLST; *TrI = hPrev; }
	else if(lpszItem == "Expert Settings") { TrI = &TVI_SETEX; *TrI = hPrev; }
	else if(lpszItem == "User Settings") { TrI = &TVI_USET; *TrI = hPrev; }
	else if(lpszItem == "Bots") { TrI = &TVI_BOTS; *TrI = hPrev; }

So my entire code ends up like this (The following code will send a message box indicating the selected Item in the treeview when selection is changed):

Code:

#include "QSDCHub.h"
#include "stdafx.h"

using namespace std;

static HTREEITEM TVI_MAIN = NULL;
static HTREEITEM TVI_HSTATS = NULL;
static HTREEITEM TVI_APP = NULL;
static HTREEITEM TVI_NTWRK = NULL;
static HTREEITEM TVI_HLST = NULL;
static HTREEITEM TVI_SETEX = NULL;
static HTREEITEM TVI_USET = NULL;
static HTREEITEM TVI_BOTS = NULL;

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
	NMHDR  *nmptr;
    switch(msg)
    {
	case WM_NOTIFY:
		switch(LOWORD(wParam))
		{
		case IDC_TVMAIN:
			{
				nmptr = (LPNMHDR) lParam;
				switch(nmptr->code)
				{
				case TVN_SELCHANGED:
					{
						std::stringstream ss;
						HTREEITEM tvi = ((LPNM_TREEVIEW)nmptr)->itemNew.hItem;
						if(tvi == TVI_MAIN) { ss << "Selected Item : Main";
							MessageBox(NULL, ss.str().c_str(), "Item Selection", MB_OK);}
						else if(tvi == TVI_HSTATS) { ss << "Selected Item : Hub Statistics";
							MessageBox(NULL, ss.str().c_str(), "Item Selection", MB_OK); }
						else if(tvi == TVI_APP) { ss << "Selected Item : Appearance";
							MessageBox(NULL, ss.str().c_str(), "Item Selection", MB_OK); }
						else if(tvi == TVI_NTWRK) { ss << "Selected Item : Network";
							MessageBox(NULL, ss.str().c_str(), "Item Selection", MB_OK); }
						else if(tvi == TVI_HLST) { ss << "Selected Item : Hublists";
							MessageBox(NULL, ss.str().c_str(), "Item Selection", MB_OK); }
						else if(tvi == TVI_SETEX) { ss << "Selected Item : Expert Settings";
							MessageBox(NULL, ss.str().c_str(), "Item Selection", MB_OK); }
						else if(tvi == TVI_USET) { ss << "Selected Item : User Settings";
							MessageBox(NULL, ss.str().c_str(), "Item Selection", MB_OK); }
						else if(tvi == TVI_BOTS) { ss << "Selected Item : Bots";
							MessageBox(NULL, ss.str().c_str(), "Item Selection", MB_OK); }
					}	
				break;
				}
			}
			break;
		}
		break;
		case WM_COMMAND:
			switch(wParam)
			{

			}
		break;
		case WM_CLOSE:
            DestroyWindow(hwnd);
        break;
        case WM_DESTROY:
            PostQuitMessage(0);
        break;
        default:
            return DefWindowProc(hwnd, msg, wParam, lParam);
    }
    return 0;
}

HTREEITEM AddItemToTree(HWND hwndTrV, LPSTR lpszItem, int nLevel)
{ 
    TVITEM tvi; 
    TVINSERTSTRUCT tvins; 
    static HTREEITEM hPrev = (HTREEITEM)TVI_FIRST; 
    static HTREEITEM hPrevRootItem = NULL; 
    static HTREEITEM hPrevLev2Item = NULL; 
    HTREEITEM hti;
	HTREEITEM *TrI = NULL;

    tvi.mask = TVIF_TEXT | TVIF_IMAGE 
               | TVIF_SELECTEDIMAGE | TVIF_PARAM; 

    tvi.pszText = lpszItem; 
    tvi.cchTextMax = sizeof(tvi.pszText)/sizeof(tvi.pszText[0]); 

    tvi.lParam = (LPARAM)nLevel; 
    tvins.item = tvi; 
    tvins.hInsertAfter = hPrev; 

    if (nLevel == 1) 
        tvins.hParent = TVI_ROOT; 
    else if (nLevel == 2) 
        tvins.hParent = hPrevRootItem; 
    else 
        tvins.hParent = hPrevLev2Item; 

    hPrev = (HTREEITEM)SendMessage(hwndTrV, 
                                   TVM_INSERTITEM, 
                                   0,
                                   (LPARAM)(LPTVINSERTSTRUCT)&tvins); 

    if (nLevel == 1)
        hPrevRootItem = hPrev; 
    else if (nLevel == 2) 
        hPrevLev2Item = hPrev; 

	if(lpszItem == "Main") { TrI = &TVI_MAIN; *TrI = hPrev; }
	else if(lpszItem == "Hub Statistics") { TrI = &TVI_HSTATS; *TrI = hPrev; }
	else if(lpszItem == "Appearance") { TrI = &TVI_APP; *TrI = hPrev; }
	else if(lpszItem == "Network") { TrI = &TVI_NTWRK; *TrI = hPrev; }
	else if(lpszItem == "Hublists") { TrI = &TVI_HLST; *TrI = hPrev; }
	else if(lpszItem == "Expert Settings") { TrI = &TVI_SETEX; *TrI = hPrev; }
	else if(lpszItem == "User Settings") { TrI = &TVI_USET; *TrI = hPrev; }
	else if(lpszItem == "Bots") { TrI = &TVI_BOTS; *TrI = hPrev; }

    if (nLevel > 1)
    { 
        hti = TreeView_GetParent(hwndTrV, hPrev); 
        tvi.mask = TVIF_IMAGE | TVIF_SELECTEDIMAGE; 
        tvi.hItem = hti; 
        TreeView_SetItem(hwndTrV, &tvi); 
    } 

    return hPrev; 
} 

BOOL InitTreeViewImageLists(HWND hwndTV) 
{ 
    return TRUE; 
} 

BOOL InitTreeViewItems(HWND hwndTrV) 
{
    int nLevel;

         AddItemToTree(hwndTrV, LPSTR("Main"), 2); 
		 AddItemToTree(hwndTrV, LPSTR("Hub Statistics"), -1);
		 AddItemToTree(hwndTrV, LPSTR("Appearance"), -1);
		 AddItemToTree(hwndTrV, LPSTR("Network"), -1);
		 AddItemToTree(hwndTrV, LPSTR("Hublists"), -1);
		 AddItemToTree(hwndTrV, LPSTR("Expert Settings"), -1);
		 AddItemToTree(hwndTrV, LPSTR("User Settings"), 2);
		 AddItemToTree(hwndTrV, LPSTR("Bots"), -1);

		 return TRUE;
} 

HWND CreateTreeView(HWND parent)
{
	HWND hwndTrV;
	RECT rcClient;

	GetClientRect(parent, &rcClient);
	hwndTrV = CreateWindowEx(0, WC_TREEVIEW, "TV_Menu", 
		WS_VISIBLE | WS_CHILD | WS_BORDER | TVS_HASLINES, 
		0, 0, 150, rcClient.bottom, parent,
		(HMENU)IDC_TVMAIN, GetModuleHandle(NULL), NULL);
	    
	
	if (!InitTreeViewItems(hwndTrV))
    { 
        DestroyWindow(hwndTrV); 
        return FALSE; 
    }
	return hwndTrV;
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
    LPSTR lpCmdLine, int nCmdShow)
{
    WNDCLASSEX wc;
    HWND hwnd;
    MSG Msg;

    wc.cbSize        = sizeof(WNDCLASSEX);
    wc.style         = 0;
    wc.lpfnWndProc   = WndProc;
    wc.cbClsExtra    = 0;
    wc.cbWndExtra    = 0;
    wc.hInstance     = hInstance;
    wc.hIcon         = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_BLKSRV));
    wc.hCursor       = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
    wc.lpszMenuName  = NULL;
    wc.lpszClassName = TEXT("QSDCHubMain");
    wc.hIconSm       = LoadIcon(wc.hInstance, MAKEINTRESOURCE(IDI_BLKSRV));

    if(!RegisterClassEx(&wc))
    {
        MessageBox(NULL, TEXT("Window Registration Failed!"), TEXT("Error!"),
            MB_ICONEXCLAMATION | MB_OK);
        return 0;
    }

    hwnd = CreateWindowEx(
        WS_EX_CLIENTEDGE,
		TEXT("QSDCHubMain"),
        TEXT("QSDCHub"),
        WS_BORDER | WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, CW_USEDEFAULT, 640, 440,
        NULL, NULL, hInstance, NULL);

	CreateTreeView(hwnd);

    if(hwnd == NULL)
    {
        MessageBox(NULL, TEXT("Window Creation Failed!"), TEXT("Error!"),
            MB_ICONEXCLAMATION | MB_OK);
        return 0;
    }

    ShowWindow(hwnd, nCmdShow);
    UpdateWindow(hwnd);

    while(GetMessage(&Msg, NULL, 0, 0) > 0)
    {
        TranslateMessage(&Msg);
        DispatchMessage(&Msg);
    }
    return Msg.wParam;
}