Listbox width size dependent of text length - mfc

My application has a window with a ListBox inside which is filled with text that changes over time, therefore Listbox entries can have several length.
I'd like to make the window and the listbox width to change dynamically dependent on the listbox entries length (in number of characters).
As an example, if my listbox has several entries and the maximum lenght is 30 characters i want to make the window and its listbox larger in width than one window that which maixum lenght is 20 characters.
What is the best way to do this?

Try something like this:
// find the longest item
CString longest;
for (int i = 0; i < m_list.GetCount(); ++i)
{
CString temp;
m_list.GetText(i, temp);
if (temp.GetLength() > longest.GetLength())
longest = temp;
}
// get the with of the longest item
CSize size = GetWindowDC()->GetTextExtent(longest);
// you need this to keep the current height
RECT rect;
m_list.GetWindowRect(&rect);
// change only width
int width = size.cx;
int height = rect.bottom - rect.top;
m_list.SetWindowPos(NULL, 0, 0, width, height, SWP_NOZORDER | SWP_NOMOVE);

What programming platform are you using? I'm guessing .NET and VB.
Put in a method to examine the contents of the list and change the size of the box and window as required:
Dim intMaxLength As Integer = 20
For Each myItem As String In ListBox1.Items
If Len(myItem) > intMaxLength Then
'Number of characters times number of pixels per character
ListBox1.Width = Len(myItem) * 10
'Me refers back to the form object
'Add a few extra pixels to give space around your listbox
Me.Width = Len(myItem) * 10 + 30
End If
Next
Hope this gives you a decent starting point.

Try this:
int maxcol = ((CHeaderCtrl*)(listctrl.GetDlgItem(0)))->GetItemCount()-1;
for (int col = 0; col <= maxcol; col++)
{
listctrl.SetColumnWidth(col, LVSCW_AUTOSIZE_USEHEADER);
}

Related

How do I resize the console window to a set number of rows and columns?

I'm writing a c++ console program for Windows using the windows.h include.
I've been trying to tailor the console size to fit my program output, but without finding a reliable way to obtain the value for width and height of a "cell" (the character boxes). I've tried both GetConsoleFontSize and GetConsoleScreenBufferInfo + GetDesktopWindow as demonstrated in the code sample below.
HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);
CONSOLE_FONT_INFO font_size;
GetConsoleFontSize(hOut,GetCurrentConsoleFont(hOut, false, &font_size));
CONSOLE_SCREEN_BUFFER_INFO csbi;
GetConsoleScreenBufferInfo(hOut, &csbi);
RECT desktop;
// Get a handle to the desktop window
const HWND hDesktop = GetDesktopWindow();
// Get the size of screen to the variable desktop
GetWindowRect(hDesktop, &desktop);
// Calculate size of one cell in the console, expressed in pixels.
COORD cell;
// Screen width/max number of columns
cell.X = desktop.right/ csbi.dwMaximumWindowSize.X;
// Screen height/max number of rows
cell.Y = desktop.bottom / csbi.dwMaximumWindowSize.Y;
// Change console size
HWND console = GetConsoleWindow();
MoveWindow(console, 0, 0, 10 * cell.X * 2, 10 * cell.Y, TRUE);
MoveWindow(console, 0, 0, 10 * font_size.dwFontSize.X * 2, 10 * font_size.dwFontSize.Y, TRUE);
Of both attempts I expected a square window able to contain just about 20x10 cells (the height of the cells seem to be 2x the width), with some margin of error on one of the examples given the integer division. However, they both seemed to be approximately 25% too small, apart from the width of the first example with is about 10% too large.
I assume that the font size does not include the spacing between letters and that the dependencies of .dwMaxWindowSize (such as buffer size etc) comes into play, but I can't quite get either method straight.
If anyone has any knowledge of how to obtain the width/height of the cells in pixels reliably I'd be very grateful. Any information regarding what goes into the cells, what affects the return value of either function or other functions I can use to achieve my goal.
Also note that the size is ultimately going to be bigger, but since I wanted to manually count the rows/columns to debug I made it smaller.
I almost have a solution now, but it still needs some work.
CONSOLE_SCREEN_BUFFER_INFO csbi;
HWND console = GetConsoleWindow();
// Resolution
RECT newClientSize, oldClientSize, newWindowSize, oldWindowSize;
// Colums, Rows
COORD newBuffer{20,50}, oldBuffer;
for (int i = 0; i < 2; i++) {
// Calculate the starting amount of columns and rows.
GetConsoleScreenBufferInfo(GetStdHandle(STD_OUTPUT_HANDLE), &csbi);
oldBuffer.X = csbi.srWindow.Right - csbi.srWindow.Left + 1;
oldBuffer.Y = csbi.srWindow.Bottom - csbi.srWindow.Top + 1;
printf("%i\n", oldBuffer.X);
printf("%i\n", oldBuffer.Y);
// Get size of client area
GetClientRect(console, &oldClientSize);
newClientSize.right = oldClientSize.right * newBuffer.X / oldBuffer.X;
newClientSize.bottom = oldClientSize.bottom * newBuffer.Y / oldBuffer.Y;
// Get size of window area
GetWindowRect(console, &oldWindowSize);
newWindowSize.right = newClientSize.right + oldWindowSize.right - oldClientSize.right;
newWindowSize.bottom = newClientSize.bottom + oldWindowSize.bottom - oldClientSize.bottom;
MoveWindow(console, 0, 0, newWindowSize.right, newWindowSize.bottom, TRUE);
}
GetConsoleScreenBufferInfo(GetStdHandle(STD_OUTPUT_HANDLE), &csbi);
oldBuffer.X = csbi.srWindow.Right - csbi.srWindow.Left + 1;
oldBuffer.Y = csbi.srWindow.Bottom - csbi.srWindow.Top + 1;
printf("%i\n", oldBuffer.X);
printf("%i\n", oldBuffer.Y);
What I don't understand is why it works when I repeat the code two or more times. The only thing I don't think I fully understand is
the different between ClientRect and WindowRect. However, as always, there's a possibility that there's something else I'm missing.

How to get width of list control in MFC application in pixels?

I'm writing a dialog based MFC application on Visual Studio 2017 in C++.
I've added an option for the user to maximize\minimize the window. As the user resizes the dialog I want to adjust the sizes of the controls. In the app there's a list control as shown in the picture below, which adjusts to the new size of the window.
before maximizing the window - the width of each column is adjusted to the list width:
after maximizing the window:
My problem is that I'm having trouble to adjust it's columns to the new size. I've seen some posts on the subject, but unfortunately I still couldn't solve the problem. I want the columns to be about the same size and to fill the whole window.
what I've tried:
1. method 1 - the problem was that the last column was much bigger than the others
void CEditableListControlDlg::OnSize(UINT nType, int cx, int cy) {
if (m_bUseWMSize) {
// adjust column width to window
for (int i = 0; i < m_EditableList.GetHeaderCtrl()->GetItemCount(); ++i) {
m_EditableList.SetColumnWidth(i, LVSCW_AUTOSIZE_USEHEADER);
}
}
m_bUseWMSize = true;
}
the variable m_bUseWMSize can be ignored - it's just a flag so I won't execute the code when the dialog is created. I've also tried switching the flage LVSCW_AUTOSIZE_USEHEADER inside SetColumnWidth to LVSCW_AUTOSIZE, but it didn't help either.
After using method 1 the list looks like this after maximizing the dialog:
2. method 2 - the problem was that the columns width wasn't affected. I think it's because the width variable has a value of 2147483647 and even if I divide it by 11 (the number of columns) it's still too big
void CEditableListControlDlg::OnSize(UINT nType, int cx, int cy) {
if (m_bUseWMSize) {
RECT rect;
m_EditableList.GetViewRect(&rect);
int width = abs(rect.left - rect.right);
int nCol = 11;
// adjust column width to window
for (int i = 0; i < m_EditableList.GetHeaderCtrl()->GetItemCount(); ++i) {
m_EditableList.SetColumnWidth(i, width/nCol);
}
}
m_bUseWMSize = true;
}
3. method 3 - I've tried to retrieve the width of the list in pixels and divide it by the number of columns. the problem was the the columns width was too small because the value of size.cx is 512
void CEditableListControlDlg::OnSize(UINT nType, int cx, int cy) {
if (m_bUseWMSize) {
CSize cz;
CSize size = m_EditableList.ApproximateViewRect(cz, -1);
int nCol = 11;
// adjust column width to window
for (int i = 0; i < m_EditableList.GetHeaderCtrl()->GetItemCount(); ++i) {
m_EditableList.SetColumnWidth(i, size.cx/11);
}
}
m_bUseWMSize = true;
}
relevant documentations:
SetColumnWidth Function
RECT struct
CSize struct
Functions ApproximateViewRect and GetViewRect
Thank you.
The easy option is to let the control do it for you :-). There is a special value you can pass (LVSCW_AUTOSIZE_USEHEADER) when sending an LVM_SETCOLUMNWIDTH message to the control, as per the following documentation topic:
https://learn.microsoft.com/en-us/windows/win32/controls/lvm-setcolumnwidth
Also referenced in that SetColumnWidth function link you mentioned in your post.
You could refer to the following code. Maybe it can help you.
bool CMFCApplication4Dlg::AdjustColumnWidth(CListCtrl* m_acclist)
{
CHeaderCtrl* pHeaderCtrl = m_acclist->GetHeaderCtrl();
int n = m_acclist->GetColumnWidth();
int nColumnCount = pHeaderCtrl->GetItemCount();
for (int i = 0; i < nColumnCount; i++)
{
m_acclist->SetColumnWidth(i, LVSCW_AUTOSIZE);
int nColumnWidth = m_acclist->GetColumnWidth(i);
m_acclist->SetColumnWidth(i, LVSCW_AUTOSIZE_USEHEADER);
int nHeaderWidth = m_acclist->GetColumnWidth(i);
m_acclist->SetColumnWidth(i, nColumnWidth > nHeaderWidth ? nColumnWidth : nHeaderWidth);
}
return true;
}
Because LVSCW_AUTOSIZE_USEHEADER will resize last column to the remaining width, it won't help you since you want to evenly distribute total width across all columns.
Similar to your method 2 you could try the following:
For each column cycle through all rows including the header and use CListCtrl::GetStringWidth to get text width in pixels. Store the maximum width of each column
Sum up all these max widths
Get width of control client rectangle with GetClientRect. If scrollbar is present subtract it with ::GetSystemMetrics (SM_CXVSCROLL)
Subtract result of 2 from 3 and divide by number of columns. Add result to each of max widths obtained in 1
Use SetColumnWidth to assign new width for each column

How to get the minimum size of a treeview control that avoids scroll bars?

I have a dialog with a tree view inside it, and would like to have the dialog re-size itself automatically when the tree is expanded or collapsed to avoid scroll bars or excessive space.
In order to do so I need some way of finding the "desired" size of the tree view, i.e., the smallest size large enough to avoid displaying scroll bars.
Any suggestions?
Edit: So, I'm halfway there. I can determine the height by counting the number of visible items and multiplying by TreeView_GetItemHeight. I still have no idea how to find the width, however...
It's not quite perfect (it doesn't seem possible to have TreeView_GetItemRect horizontally include the whole line up to the end of text), but the following works great for my use case with disabled horizontal scrolling.
void Dialog::getDimensionTreeView(unsigned int id,
unsigned int &width, unsigned int &height) {
HWND item = GetDlgItem((HWND)_hwnd, id);
if(!item) {
width = 0;
height = 0;
return;
}
RECT area = { };
HTREEITEM node = TreeView_GetRoot(item);
do {
RECT rc;
LPRECT prc = &rc;
// Ideally this would use `fItemRect`=FALSE, but that seems
// to just return the current width of the treeview control.
TreeView_GetItemRect(item, node, prc, TRUE);
if(rc.left < area.left) area.left = rc.left;
if(rc.right > area.right) area.right = rc.right;
if(rc.top < area.top) area.top = rc.top;
if(rc.bottom > area.bottom) area.bottom = rc.bottom;
} while((node = TreeView_GetNextVisible(item, node)));
width = area.right - area.left;
height = area.bottom - area.top;
}
Thanks to Hans Passant for putting me on the right track.

Cannot get text with Unicode (including Chinese) characters to line up with MFC using a CRichEditCtrl

I have a CRichEditCtrl (actually I have a class that is a subclass of a CRichEditCtrl, a class that I defined) that is populated by many lines of text with both horizontal and vertical scroll bars. The purpose of this control is to display a string that is searched for in a larger text along with n characters to the right and left (e.g. if the user searches for "the" then they would get a list of all the instances of "the" in the text with (if n = 100) 100 characters to the left and right of each found instance to provide context).
The query string needs to be lined up between each row. Before this program had Unicode support, just setting the font to Courier did the trick, but now that I've enabled Unicode support, this no longer works.
I've tried using monospaced fonts, but as far as I can tell, there aren't any that are for all characters. It seems to me that the latin characters all have one size, and the Chinese characters have another (I've noticed lines of text with all latin characters line up and ones with all Chinese characters line up, but ones with both do not line up).
I've also tried center aligning the text. Since the query string in each line is in the exact center, they should all line up, but I cannot seem to get this to work, the SetParaFormat call seems to just get ignored. Here's the code I used for that:
long spos, epos;
GetSel(spos, epos);
PARAFORMAT Pfm;
GetParaFormat(Pfm);
Pfm.dwMask = (Pfm.dwMask | PFM_ALIGNMENT);
Pfm.wAlignment = PFA_CENTER;
SetSel(0, -1);
SetParaFormat(Pfm);
SetSel(spos, epos);
I do this everytime text is inserted in the ctrl, but it has no affect on the program.
Is there anyway to get the query word in each line of text to line up even when there are interspersed Chinese and latin characters? (and possibly any other character set)
See http://msdn.microsoft.com/en-us/library/bb787940(v=vs.85).aspx, in particular the cTabCount and rgxTabs members of the PARAFORMAT (or PARAFORMAT2) structure, which allow you to set tabstops.
Okay so I managed to solve it. For future reference, here's what I did:
First, I tried to find a monospaced font, but I was unable to find any that were truly monospaced (had latin and chinese characters as the same width).
Next, I tried to center the text in the window. I was unable to do this until I realized that having Auto HScroll set to true (ES_AUTOHSCROLL defined for the rich edit control) caused setParaFormat to ignore me trying to center the text. After I disabled it and manually set the size of the drawable text area, I was able to center the text. Just in case anyone is curious, here's the code I used to set the width of the drawable area in the rich edit box:
CDC* pDC = GetDC();
long lw = 99999999;
SetTargetDevice(*GetDC(), lw);
I just set lw arbitrarily large so I could test to see if centering the text worked. It did not. As it turns out, when the rich edit control centers the text, it bases it off the draw width of the text, not off the number of characters. I assumed that since there were the same number of characters on either side of the query string then that would cause the string to be centered, but this was not the case.
The final solution I tried was the one suggested by ymett. After some tweaking I came up with a function called alignText() that's called after all the text has been inserted into the rich edit control. Here's the function (Note: each line in the control had tabs inserted before this function was called: one at the beginning of the line and one after the query string e.g. "string1-query-string2" becomes "\tstring1-query\t-string2")
void CFormViewConcordanceRichEditCtrl::alignText()
{
long maxSize = 0;
CFont font;
LOGFONT lf = {0};
CHARFORMAT cf = {0};
this->GetDefaultCharFormat(cf);
//convert a CHARFORMAT struct into a LOGFONT struct
if (cf.dwEffects & CFE_BOLD)
lf.lfWeight = FW_BOLD;
else
lf.lfWeight = FW_NORMAL;
if (cf.dwEffects & CFE_ITALIC)
lf.lfItalic = true;
if (cf.dwEffects & CFE_UNDERLINE)
lf.lfUnderline = true;
if (cf.dwEffects & CFE_STRIKEOUT)
lf.lfStrikeOut = true;
lf.lfHeight = cf.yHeight;
_stprintf(lf.lfFaceName, _T("%s"), cf.szFaceName);
lf.lfCharSet = DEFAULT_CHARSET;
lf.lfOutPrecision = OUT_DEFAULT_PRECIS;
font.CreateFontIndirect(&lf);
//create a display context
CClientDC dc(this);
dc.SetMapMode(MM_TWIPS);
CFont *pOldFont = dc.SelectObject(&font);
//find the line that as the longest preceding string when drawn
for(int i = 0; i < m_pParent->m_nDataArray; i++)
{
CString text = m_pParent->DataArray[i].text.Left(BUFFER_LENGTH + m_pParent->generateText.GetLength());
text.Replace(_T("\r"), _T(" "));
text.Replace(_T("\n"), _T(" "));
text.Replace(_T("\t"), _T(" "));
CRect rc(0,0,0,0);
dc.DrawText(text, &rc, DT_CALCRECT);
int width = 1.0*cf.yHeight/fabs((double)rc.bottom - rc.top)*(rc.right - rc.left);
width = dc.GetTextExtent(text).cx;
if(width > maxSize)
maxSize = width;
}
dc.SelectObject(pOldFont);
//this calulates where to place the first tab. The 0.8 is a rought constant calculated by guess & check, it may be innacurate.
long tab = maxSize*0.8;
PARAFORMAT pf;
pf.cbSize = sizeof(PARAFORMAT);
pf.dwMask = PFM_TABSTOPS;
pf.cTabCount = 2;
pf.rgxTabs[0] = tab + (2 << 24); //make the first tab right-aligned
pf.rgxTabs[1] = tab + 25;
//this is to preserve the user's selection and scroll positions when the selection is changed
int vScroll = GetScrollPos(SB_VERT);
int hScroll = GetScrollPos(SB_HORZ);
long spos, epos;
GetSel(spos, epos);
//select all the text
SetSel(0, -1);
//this call is very important, but I'm not sure why
::SendMessage(GetSafeHwnd(), EM_SETTYPOGRAPHYOPTIONS, TO_ADVANCEDTYPOGRAPHY, TO_ADVANCEDTYPOGRAPHY);
this->SetParaFormat(pf);
//now reset the user's selection and scroll positions
SetSel(spos, epos);
::SendMessage(GetSafeHwnd(),
WM_HSCROLL,
(WPARAM) ((hScroll) << 16) + SB_THUMBPOSITION,
(LPARAM) NULL);
::SendMessage(GetSafeHwnd(),
WM_VSCROLL,
(WPARAM) ((vScroll) << 16) + SB_THUMBPOSITION,
(LPARAM) NULL);
}
Essentially what this function does is make the first tab stop right-aligned and set it at some point x to the right in the control. It then makes the second tab stop a small distance to the right of that, and makes it left-aligned. So all the text from the beginning of each line to the end of the query string (from the first \t to the second \t) is pushed toward the right against the first tab stop, and all the remaining text is pushed toward the left against the second tab stop, causing the query string to be aligned between all the lines in the control. The first part of the function finds out x (by finding out how long each line will be drawn and taking the max) and the second part sets the tab stops.
Thanks again to ymett for the solution.

How to get size of check and gap in check box?

I have a check box that I want to accurately measure so I can position controls on a dialog correctly. I can easily measure the size of the text on the control - but I don't know the "official" way of calculating the size of the check box and the gap before (or after) the text.
I'm pretty sure the width of the checkbox is equal to
int x = GetSystemMetrics( SM_CXMENUCHECK );
int y = GetSystemMetrics( SM_CYMENUCHECK );
You can then work out the area inside by subtracting the following ...
int xInner = GetSystemMetrics( SM_CXEDGE );
int yInner = GetSystemMetrics( SM_CYEDGE );
I use that in my code and haven't had a problem thus far ...
Short answer:
Long Version
From MSDN Layout Specifications: Win32, we have the specifications of the dimensions of a checkbox.
It is 12 dialog units from the left edge of the control to the start of the text:
And a checkbox control is 10 dialog units tall:
Surfaces and Controls Height (DLUs) Width (DLUs)
===================== ============= ===========
Check box 10 As wide as possible (usually to the margins) to accommodate localization requirements.
First we calculate the size of a horizontal and a vertical dialog unit:
const dluCheckBoxInternalSpacing = 12; //12 horizontal dlus
const dluCheckboxHeight = 10; //10 vertical dlus
Size dialogUnits = GetAveCharSize(dc);
Integer checkboxSpacing = MulDiv(dluCheckboxSpacing, dialogUnits.Width, 4);
Integer checkboxHeight = MulDiv(dluCheckboxHeight, dialogUnits.Height, 8);
Using the handy helper function:
Size GetAveCharSize(HDC dc)
{
/*
How To Calculate Dialog Base Units with Non-System-Based Font
http://support.microsoft.com/kb/125681
*/
TEXTMETRIC tm;
GetTextMetrics(dc, ref tm);
String buffer = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
Size result;
GetTextExtentPoint32(dc, buffer, 52, out result);
result.Width = (result.X/26 + 1) / 2; //div uses trunc rounding; we want arithmetic rounding
result.Height = tm.tmHeight;
return result;
}
Now that we know how many pixels (checkboxSpacing) to add, we calculate the label size as normal:
textRect = Rect(0,0,0,0);
DrawText(dc, Caption, -1, textRect, DT_CALCRECT or DT_LEFT or DT_SINGLELINE);
chkVerification.Width = checkboxSpacing+textRect.Right;
chkVerification.Height = checkboxHeight;
Bonus Reading
What's a dialog unit?
A dialog is a unit of measure based on the user's preferred font size. A dialog unit is defined such that the average character is 4 dialog units wide by 8 dialog units high:
This means that dialog units:
change with selected font
changed with selected DPI setting
are not square
Note: Any code released into public domain. No attribution required.
Sorry for resurrecting this old thread. I recently found myself wondering about the exact same question. Currently, none of the answers above give a result consistent with Windows 10 for different fonts and font sizes, especially in high-DPI environments.
Instead, it seems that the correct result is obtained by
SIZE szCheckBox;
GetThemePartSize(hTheme, hDC, BP_CHECKBOX, CBS_UNCHECKEDNORMAL, &rcBackgroundContent, TS_TRUE, &szCheckBox);
for the size of the checkbox itself. And
SIZE szZeroCharacter;
GetTextExtentPoint32(hDC, L"0", 1, &szZeroCharacter);
int iGapWidth = szZeroCharacter.cx / 2;
for the width of the gap. After trying a lot of different methods inspired by the posts above, I found L"0" in the dissembly of comctl32.dll. And while it looks like a joke to me (not necessarily a good one), I suspect it's a holdover from the old days when this might have been a good enough approximation of 2DLU.
Disclaimer: While I tested the result with various fonts and different sizes on Windows 10, I have not attempted to verify that it also holds on any other (older) version of the operating system.
It is a shame that Microsoft did not provide a way to know this for sure. I was struggling with the same question and the answer provided above is not complete. The main problem with it is that if the font of the dialog window is set to something other than the default size, that solution will not work because checkboxes will be resized.
Here's how I solved this issue (it is just an approximation that seems to have worked for me). The code is for MFC project.
1 - Create two test controls on your form, a checkbox and a radio box:
2 - Define the following custom struct:
struct CHECKBOX_DIMS{
int nWidthPx;
int nHeightPx;
int nSpacePx; //Space between checkbox and text
CHECKBOX_DIMS()
{
nWidthPx = 0;
nHeightPx = 0;
nSpacePx = 0;
}
};
3 - Call the following code when form initializes for each of the test controls (that will measure them and remove them so that end-users don't seem them):
BOOL OnInitDialog()
{
CDialog::OnInitDialog();
//Calculate the size of a checkbox & radio box
VERIFY(GetInitialCheckBoxSize(IDC_CHECK_TEST, &dimsCheckBox, TRUE));
VERIFY(GetInitialCheckBoxSize(IDC_RADIO_TEST, &dimsRadioBox, TRUE));
//Continue with form initialization ...
}
BOOL GetInitialCheckBoxSize(UINT nCtrlID, CHECKBOX_DIMS* pOutCD, BOOL bRemoveCtrl)
{
//Must be called initially to calculate the size of a checkbox/radiobox
//'nCtrlID' = control ID to measure
//'pOutCD' = if not NULL, receives the dimensitions
//'bRemoveCtrl' = TRUE to delete control
//RETURN:
// = TRUE if success
BOOL bRes = FALSE;
//Get size of a check (not exactly what we need)
int nCheckW = GetSystemMetrics(SM_CXMENUCHECK);
int nCheckH = GetSystemMetrics(SM_CYMENUCHECK);
//3D border spacer (not exactly what we need either)
int nSpacerW = GetSystemMetrics(SM_CXEDGE);
//Get test checkbox
CButton* pChkWnd = (CButton*)GetDlgItem(nCtrlID);
ASSERT(pChkWnd);
if(pChkWnd)
{
CRect rcCheckBx;
pChkWnd->GetWindowRect(&rcCheckBx);
//We need only the height
//INFO: The reason why we can't use the width is because there's
// an arbitrary text followed by a spacer...
int h = rcCheckBx.Height();
CDC* pDc = pChkWnd->GetDC();
if(pDc)
{
//Get horizontal DPI setting
int dpiX = pDc->GetDeviceCaps(LOGPIXELSX);
//Calculate
if(pOutCD)
{
//Use height as-is
pOutCD->nHeightPx = h;
//Use height for the width
pOutCD->nWidthPx = (int)(h * ((double)nCheckW / nCheckH));
//Spacer is the hardest
//INFO: Assume twice and a half the size of 3D border &
// take into account DPI setting for the window
// (It will give some extra space, but it's better than less space.)
// (This number is purely experimental.)
// (96 is Windows DPI setting for 100% resolution setting.)
pOutCD->nSpacePx = (int)(nSpacerW * 2.5 * dpiX / 96.0);
}
//Release DC
pChkWnd->ReleaseDC(pDc);
if(bRemoveCtrl)
{
//Delete window
bRes = pChkWnd->DestroyWindow();
}
else
{
//Keep the window
bRes = TRUE;
}
}
}
return bRes;
}
4 - Now you can easily resize any checkbox or radio box by calling this:
//Set checkbox size & new text
VERIFY(SetCheckBoxTextAndSize(this, IDC_CHECK_ID, &dimsCheckBox, L"New text") > 0);
//Just resize radio box
VERIFY(SetCheckBoxTextAndSize(this, IDC_RADIO_ID, &dimsRadioBox, NULL) > 0);
int SetCheckBoxTextAndSize(CWnd* pParWnd, UINT nCheckBoxID, CHECKBOX_DIMS* pDims, LPCTSTR pNewText)
{
//Set size of the checkbox/radio to 'pNewText' and update its size according to its text
//'pParWnd' = parent dialog window
//'nCheckBoxID' = control ID to resize (checkbox or radio box)
//'pDims' = pointer to the struct with checkbox/radiobox dimensions
//'pNewText' = text to set, or NULL not to change the text
//RETURN:
// = New width of the control in pixels, or
// = 0 if error
int nRes = 0;
ASSERT(pParWnd);
ASSERT(pDims);
CButton* pChkWnd = (CButton*)pParWnd->GetDlgItem(nCheckBoxID);
ASSERT(pChkWnd);
if(pChkWnd)
{
CDC* pDc = pChkWnd->GetDC();
CFont* pFont = pChkWnd->GetFont();
if(pDc)
{
if(pFont)
{
//Make logfont
LOGFONT lf = {0};
if(pFont->GetLogFont(&lf))
{
//Make new font
CFont font;
if(font.CreateFontIndirect(&lf))
{
//Get font from control
CFont* pOldFont = pDc->SelectObject(&font);
//Get text to set
CString strCheck;
if(pNewText)
{
//Use new text
strCheck = pNewText;
}
else
{
//Keep old text
pChkWnd->GetWindowText(strCheck);
}
//Calculate size
RECT rc = {0, 0, 0, 0};
::DrawText(pDc->GetSafeHdc(), strCheck, strCheck.GetLength(), &rc, DT_CALCRECT | DT_NOPREFIX | DT_SINGLELINE);
//Get text width
int nTextWidth = abs(rc.right - rc.left);
//See if it's valid
if(nTextWidth > 0 ||
(nTextWidth == 0 && strCheck.GetLength() == 0))
{
//Get location of checkbox
CRect rcChk;
pChkWnd->GetWindowRect(&rcChk);
pParWnd->ScreenToClient(rcChk);
//Update its size
rcChk.right = rcChk.left + pDims->nWidthPx + pDims->nSpacePx + nTextWidth;
//Use this line if you want to change the height as well
//rcChk.bottom = rcChk.top + pDims->nHeightPx;
//Move the control
pChkWnd->MoveWindow(rcChk);
//Setting new text?
if(pNewText)
{
pChkWnd->SetWindowText(pNewText);
}
//Done
nRes = abs(rcChk.right - rcChk.left);
}
//Set font back
pDc->SelectObject(pOldFont);
}
}
}
//Release DC
pChkWnd->ReleaseDC(pDc);
}
}
return nRes;
}
I'd like to give my 2 cents on the matter since iv spent an entire day working on an accurate solution for this problem that takes DPI awareness and fonts into consideration.
First define the checkbox's size in units.
#define CHECKBOX_INTERNAL_SIZE 12
Then i defined a function for converting units to pixels. NOTE: MulDiv may work just as good.
double dpi_MulDiv(double nNumber, double nNumerator, double nDenominator)
{
return (nNumber * nNumerator) / nDenominator;
}
Finally the function that does the magic. SEE the code comments for details.
//
// Get the minimum size of the Checkbox.
// NOTE: The font of the control must be set before calling this function.
//
SIZE dpi_GetCheckBoxWidth(HWND hWnd, int monitorDpi)
{
HDC dc;
HFONT hFont;
HFONT oldFont;
TEXTMETRIC tm;
double checkboxSize;
double whiteSpace;
WCHAR sourceString[128];
RECT txtRect;
SIZE size;
dc = GetDC(hWnd);
// Note that GetDC returns an uninitialized DC, which has "System" (a bitmap font) as the default font; thus the need to select a font into the DC.
hFont = (HFONT)SendMessage(hWnd, WM_GETFONT, 0, 0);
oldFont = (HFONT)SelectObject(dc, hFont);
// Get the Checkbox width.
checkboxSize = round(dpi_MulDiv(CHECKBOX_INTERNAL_SIZE, monitorDpi, 96));
// Get the space between the Checkbox and text.
GetTextMetrics(dc, &tm);
whiteSpace = round((double)tm.tmAveCharWidth / 2.0f);
// Get the Text width.
txtRect = { 0, 0, 0, 0 };
if (GetWindowTextW(hWnd, sourceString, 128) != 0)
{
DrawTextW(dc, sourceString, -1, &txtRect, DT_CALCRECT | DT_LEFT | DT_SINGLELINE);
}
// Cleanup.
SelectObject(dc, oldFont);
ReleaseDC(hWnd, dc);
// Done.
size.cx = (LONG)checkboxSize + (LONG)whiteSpace + txtRect.right + 3;
size.cy = ((LONG)checkboxSize < txtRect.bottom) ? txtRect.bottom : (LONG)checkboxSize;
return size;
}
I added + 3 on the last line that computes the width as a way to adjust for little irregularities. Feed back on this is welcomed. Iv only tested on Windows 10 thus far with different fonts and sizes.
This code doesn't work on Win7 with scaled UI (fonts 125% larger or 150% larger). The only thing that seems to work is:
int WID = 13 * dc.GetDeviceCaps(LOGPIXELSX) / 96;
int HEI = 13 * dc.GetDeviceCaps(LOGPIXELSY) / 96;
Ok dudes my way is maybe not the fastes to use in runtime, but it works for me in any case i have tested so far.
In the beginnin of my proggys i put in a function to get the size and store it in a global variable (yeah i have heard this would be bad, but i dont care about this)
here the explanation:
Create a treeview (invisible if u want)
Create an imagelist with atleast 1 image inside (size 16x16)
Set the imagelist to the treeview ("TVSIL_NORMAL")
Get the "TVSIL_STATE" imagelist from the treeview (u have to create "TVSIL_NORMAL" before, otherwise this one will fail!)
Use ImageList_GetIconSize(..) and store the size. Wow, the checkboxs and the radio-buttons have the same size as the state icons of the treeview. Now u have what u want!
Destroy the "TVSIL_NORMAL" imagelist
Destroy the treeview
this code needs only a few microseconds at the beginning of my proggies and i can use the value everytime i need it.
Preamble:
I had the same question while trying to determine the needed size of the checkbox control for a given text and found that the existing answers didn't really work for me, for several reasons:
SM_CXMENUCHECK doesn't account for the gap. In fact, I'm not convinced this is even for regular checkboxes, although it may have the same value. It may also be dependent on visual styles being enabled.
The other answers were overly complicated and felt a bit hacky (no disrespect intended, it is MS that don't make this easy).
The stated 12DLU layout was very helpful, although again feels arbitrary without a system metric to rely on.
The answers I tried still didn't yield a high enough pixel value to stop the checkbox text from wrapping.
My investigation:
I looked at how Wine reproduces the behavior and found that it also gives the same results as simply assuming 12DLU. However, the text still wrapped unless I added an extra 3 pixels to the width (even though the text should fit fine without). I also noticed that GetTextExtentPoint32 yields a value of 3 for an empty string (hmmm...)
Turning off the BS_MULTILINE style obviously stopped the text wrapping. My guess is that DrawTextW's word wrapping calculations are imperfect.
At this point I decided that the simplest solution was to just add 1 extra space to GetTextExtentPoint32, so that there would definitely be enough pixels. The over-estimate of a couple of pixels was acceptable to me.
Note that this all assumes your application is manifested as DPI aware. Otherwise I found the checkbox appeared much larger on some Windows 7 systems (not all though).
My (mostly Wine's) solution:
// This code gets the size of a piece of text and adds the size of a
// checkbox and gap. Note that this is very rough code with no error handling.
BOOL isCheckbox = TRUE;
HWND dialog = ... // Your control or dialog
HFONT font = ... // The font your control will use if it hasn't been set yet
PTCHAR text = ... // Your text
HFONT currentFont;
SIZE size;
HDC dc = GetDC(dialog);
if (!font) {
font = (HFONT)SendMessage(dialog, WM_GETFONT, 0, 0);
}
currentFont = (HFONT)SelectObject(dc, font); // NB: You should add error handling here
if (isCheckbox) {
// Or you can disable BS_MULTILINE
_tcscat(text, TEXT(" ")); // NB: This assumes text is allocated for +1 char
}
GetTextExtentPoint32(dc, text, _tcslen(text), &size); // NB: You should add error handling here
if (isCheckbox) {
int checkBoxWidth = 12 * GetDeviceCaps(dc, LOGPIXELSX ) / 96 + 1;
int checkBoxHeight = 12 * GetDeviceCaps(dc, LOGPIXELSY ) / 96 + 1;
int textOffset;
GetCharWidthW(dc, '0', '0', &textOffset);
textOffset /= 2;
size->cx += checkBoxWidth + textOffset;
if (size->cy < checkBoxHeight) {
size->cy = checkBoxHeight;
}
}
if (currentFont) {
SelectObject(dc, currentFont);
}
ReleaseDC(dialog, dc);