C / C++ / MFC

Re: Calculating the Size of Rich Edit "bottomless" control

27-Apr-09 9:00

Hi,

I have been doing some research regarding how to fit a specfied number of characters
In a Rich edit control the following article on the codeProject helped
"http://www.codeproject.com/KB/edit/richeditsize.aspx"

"Calculating a Rich Edit Control Minimum Size"

I get the Idea behind it however on thing is missing the Author starts with

a computation of half of the width of the Client area

int cxLast = ::GetSystemMetrics( SM_CXFULLSCREEN ) / 2;

If I want a certian number of characters to fix in the line of a rich edit control

wouldn't I want to know the Font of The Dialogbox/Richeditcontrol

would that mean instantating of CDC object

Doing a SlectObject getting the Logfont Structure

My question is "Am I losing it" meaning I am really making this more difficult then I have to ?????

Or am I on the right Path

thankx

Stuart Dootson27-Apr-09 14:02

Re: Calculating the Size of Rich Edit "bottomless" control

27-Apr-09 14:02

ForNow wrote:
If I want a certian number of characters to fix in the line of a rich edit control
wouldn't I want to know the Font of The Dialogbox/Richeditcontrol

That might well work for a mono-space font like Courier or Courier New. But what about proportional fonts like Arial or Times New Roman? With a font like that, the number of characters you can fit into a particular width depends on the characters you're displaying - 'W' is a lot wider than 'l'!!

ForNow wrote:
would that mean instantating of CDC object
Doing a SlectObject getting the Logfont Structure

In a word yes. And then use GetTextExtentPoint32[^] to get the size of a string you specify or GetTextMetrics[^] (to get font metrics including average character width).

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

ForNow27-Apr-09 16:37

Re: Calculating the Size of Rich Edit "bottomless" control

27-Apr-09 16:37

First I think I finally Understand from your reply and the sample code in the above mentioned URL why they call RichEdittext bottomless ... cuase the height is always the same for a font while the width of each character varies

thats why in the sample code the author was looking for what particualr height will have the right richedit control

width

I know people here always tell me to do reasearch before asking my questions and this time I thought I did

but tell me what you think of this solution

Cfont* font richedit->GetFont();

LOGFONT lf;

font->GetlogFont(&lf);

now lf.lfwidth * richedit->Linelength(-1); // multiple the avergage width by the number of charcters on a line

In a relasted issue I cann't seem to get the notification handler to kick off, I thought that after issuing

Requestresize()Control would be passed to it, I made a breakpoint in the begining of the method and it was never

invoked???

below is 3 pices of information the 1) the declaration of the method 2) the message map entry 3) the actual method

I think I have them all coded correctly

1) afx_msg void OnRequestResize(NMHDR* pNMHDR, LRESULT* pResult);

2) ON_NOTIFY(EN_REQUESTRESIZE,IDC_RICHEDIT21,OnRequestResize)

3) void Show_storage::OnRequestResize( NMHDR* pNMHDR, LRESULT* pResult )
{
_ASSERT( pNMHDR->code == EN_REQUESTRESIZE );

// Storing the requested sized to be used in the binary search

.
.
.

thankx again

Stuart Dootson28-Apr-09 5:12

To receive EN_REQUESTRESIZE notification messages, you must enable the notification by using the EM_SETEVENTMASK message.[^]

28-Apr-09 5:12

ForNow wrote:
First I think I finally Understand from your reply and the sample code in the above mentioned URL why they call RichEdittext bottomless

No - the 'bottomless' rich-edit control is one that sends notifications to its parent that it needs to be resized when the text it contains changes enough that the control can't contain it all any more.

ForNow wrote:
but tell me what you think of this solution

That's probably what I'd do Smile | :)

ForNow wrote:
In a relasted issue I cann't seem to get the notification handler to kick off, I thought that after issuing
Requestresize()Control would be passed to it, I made a breakpoint in the begining of the method and it was never
invoked???

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Re: Calculating the Size of Rich Edit "bottomless" control

ForNow28-Apr-09 9:10

Re: Calculating the Size of Rich Edit "bottomless" control

28-Apr-09 9:10

>No - the 'bottomless' rich-edit control is one that sends notifications to its parent >that it needs to be resized when the text it contains changes enough that the control >can't contain it all any more.

I thought just issuing the editctrl.RequestResize(); sends the EN_REQUESTRESIZE to the parent with REQSIZE structure containing the new demissions it ( child rich edit control) would like

>To receive EN_REQUESTRESIZE notification messages, you must enable the notification by >using the EM_SETEVENTMASK message.[^]

I did that I think the problem might be the named I choose foor the notification Handler "OnRequestResize"

I made a prototype of the function in the Dialog Class since thats the parent that will receive the notification

However I when try to set as Break point I get message "No code associated with this Location"

When I try to see the assembler code generated none is for the first part of the method

Could it be that the name I choose for the Event handle OnRequestResize is Similar to a protected method call onRequestResize (lower case o )thats giving me problems ??

I'll try to change the name ..

Stuart Dootson28-Apr-09 10:51

Re: Calculating the Size of Rich Edit "bottomless" control

28-Apr-09 10:51

I've just added a rich-edit control to a sample MFC dialog app.

In the OnInitDialog handler, I added this:

UpdateData();
richEd.SetEventMask(ENM_REQUESTRESIZE);

Here's the message map entry

ON_NOTIFY(EN_REQUESTRESIZE, IDC_RICHEDIT21, &CmfcdialogDlg::OnEnRequestresizeRichedit21)

Here's the notification handler

void CmfcdialogDlg::OnEnRequestresizeRichedit21(NMHDR *pNMHDR, LRESULT *pResult)
{
   REQRESIZE *pReqResize = reinterpret_cast<reqresize>(pNMHDR);
   // TODO:  The control will not send this notification unless you override the
   // CDialog::OnInitDialog() function to send the EM_SETEVENTMASK message
   // to the control with the ENM_REQUESTRESIZE flag ORed into the lParam mask.

   // TODO:  Add your control notification handler code here

   *pResult = 0;
}</reqresize>

I request the resize with

richEd.RequestResize();

in a 'button click' event handler.

My EN_REQUESTRESIZE handler gets called.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

ForNow28-Apr-09 11:17

Re: Calculating the Size of Rich Edit "bottomless" control

28-Apr-09 11:17

TODO: The control will not send this notification unless you override the // CDialog::OnInitDialog() function to send the EM_SETEVENTMASK message // to the control with the ENM_REQUESTRESIZE flag ORed into the lParam mask.

This accomplished in the OnInitDialog function issuing
richED.SetEventMask(ENM_REQUESTRESIZE);

I dont actually have to do a
CmfcdialogDlg::SendMessage(EM_SETEVENTMASK,0,(LPARAM)ENM_REQUESTRESIZE);

thankx

ForNow28-Apr-09 18:20

Re: Calculating the Size of Rich Edit "bottomless" control

28-Apr-09 18:20

Hi,

thankx for all your all I see that you are in the UK 5 hours ahead of me as I am in the states on the East Coast

I got requestresize exit working (excuse me for my use of words "exit") as I Work as A MainFrame programmer

I have a couple of more general questions

the porpouse of the Bottomless Rich edit control is to get a perfect fit in Height and with for the Text

Depending on the amount of text and where you would like to break up the text is Where the Notfication Handler

will help

Last question I have been using WM_SETTEXT to get text to the Rich edit is the Steamin method a better way of doing

this

thankx again

Stuart Dootson28-Apr-09 18:58

Re: Calculating the Size of Rich Edit "bottomless" control

28-Apr-09 18:58

ForNow wrote:
Last question I have been using WM_SETTEXT to get text to the Rich edit is the Steamin method a better way of doing this

If the text is large (megabyte+) or is actually RTF (contains markup), yes. I've seen a couple of pages that suggest you should always use EM_STREAMIN because WM_SETTEXT is unreliable with rich edit controls - but if it's working for you...

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

ForNow28-Apr-09 22:47

WriteProcessMemory error 5

28-Apr-09 22:47

thankx again

Snoepie27-Apr-09 6:48

27-Apr-09 6:48

when excuting this (procID is a control panel applet)

HANDLE lView=OpenProcess(PROCESS_ALL_ACCESS,false,procID);
if (lView)
{
if ( !LookupPrivilegeValue(NULL,SE_DEBUG_NAME,&tokenLuid ) )
j=GetLastError();
tokenPriv.PrivilegeCount = 1;
tokenPriv.Privileges[0].Luid = tokenLuid;
tokenPriv.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
tokenHandle=NULL;
if (!OpenProcessToken(lView,TOKEN_ADJUST_PRIVILEGES,&tokenHandle))
j=GetLastError();

if ( !AdjustTokenPrivileges(tokenHandle,FALSE,&tokenPriv,sizeof(TOKEN_PRIVILEGES) , (PTOKEN_PRIVILEGES) NULL, (PDWORD) NULL) )
j=GetLastError();

// Allocate virtual memory for ListView
LVITEM *_lvi=(LVITEM*)VirtualAllocEx(lView, NULL, sizeof(LVITEM),MEM_COMMIT, PAGE_READWRITE);
if (!VirtualQueryEx(lView,_lvi,&memBasicInfo,sizeof(MEMORY_BASIC_INFORMATION)))
j=GetLastError();

no errors are triggered, memBasicInfo returns the correct parameters, ie i have full access to the allocated memory. But if i follow it up by:

if (WriteProcessMemory(lView, _lvi, &lvi, sizeof(LVITEM),&byteCount))
j=GetLastError();

i still get error 5, but bytecount gives the correct count. I disabled the antivirus scanner, so it's not interfering

I am flabbergasted.

CPallini27-Apr-09 7:13

27-Apr-09 7:13

Why are you calling GetLastError on WriteprocessMemory success?
Smile | :)

Snoepie27-Apr-09 8:28

27-Apr-09 8:28

the call doesn't complete..... The bytecount written is correct, but the memory addressed by the call stays empty.
Also in MSDN is stated that a Write call my fail whilst still returning no fail error code.

After doing a sendmessage LVM_GetItemState to listView, the call returns empty as well.

So the memory location seems to be inacessible, which is bizarre because i also have this:

lvi.pszText=_item;
WriteProcessMemory(lView, _lvi, &lvi, sizeof(LVITEM), NULL);
SendMessage(listView, LVM_GETITEMTEXT, NULL, (LPARAM)_lvi);
ReadProcessMemory(lView, _item, item, 512, NULL);

and that returns with the correct itemtext......

Luc Pattyn27-Apr-09 8:17

Luc Pattyn

27-Apr-09 8:17

GetLastError() returns the last error that occurred, which didn't necessarily happen in the last function call. That is way it is called GetLastError() and not GetError().

You normally want to stop a sequence of operations at the first error, so you could and should structure your code like this:

result=callFunction1();
if (result==OK) result=callFunction2();
if (result==OK) result=callFunction3();
if (result!=OK) log("it went wrong; error = ", GetLastError());

Luc Pattyn [Forum Guidelines] [My Articles]

Avoiding unwanted divs (as in "articles needing approval") with the help of this FireFox add-in

Snoepie27-Apr-09 8:29

27-Apr-09 8:29

tnx for the input, but the original code is spiked with GetLastErrors, took some out to shorten code for viewing.

Luc Pattyn27-Apr-09 8:50

Luc Pattyn

27-Apr-09 8:50

Yeah, great. When the error handling code indicates some problem, show us fictitious code. Someone will make the right guess anyhow?

Unsure | :~

Luc Pattyn [Forum Guidelines] [My Articles]

Avoiding unwanted divs (as in "articles needing approval") with the help of this FireFox add-in

CPallini27-Apr-09 22:36

27-Apr-09 22:36

They must protect their brilliant code against industrial espionage, my friend.
Roll eyes | :rolleyes:

Snoepie29-Apr-09 5:50

29-Apr-09 5:50

found it:

Microsoft Windows Vista and later. When a message is blocked by UIPI the last error, retrieved with GetLastError, is set to 5 (access denied).

took me a full week to discover this tidbit. Tnx MS

CPallini29-Apr-09 6:33

Please help with thisBasic C Program

29-Apr-09 6:33

Good: tenacity wins, eventually.
Smile | :)

biggiant2200027-Apr-09 5:45

biggiant22000

27-Apr-09 5:45

I need help with a programto keep records and perform statistical analysis for a class of students.
the class has 40 students, there are 5 quizzes, and each student identified by a 4 digit student number

Re: Please help with thisBasic C Program [modified]

CPallini27-Apr-09 6:38