yang686526

singledoc in .net
singledoc in .net
hello
i must admit, i have already posted this question. for some reason i have gotten no response so far. chances are, my question was just not accurate enough. anyway, here i go again (hopefully a little clearer...):
i'd like to implement a viewer using .net windows forms. especially i'd like to know if it is possible to do that without mfc and in what time this task could be accomplished. i've studied the singledoc example and also found a post about the very same topic:
device->update access violation (c++ .net)
hello
i searched the forum once again and found this post:
i used the posted vs project from "davidenglish" and made it compile and run. it shows a simple windows form with an control in it. the handle to the control is passed to the device-properties (device is created by the wingdi module). the loaded dxf-drawing is not shown. when i call device->update() i get an access violation.
as recommended in other posts, i keep the smartpointers to the used od-objects.
can you please explain to me, why i am getting this access violation and how (if possible) i can avoid it?
this is the code (originally davidenglish's code):
code:
#pragma once
#pragma warning (disable:4482)
#include "odacommon.h"
#include <dbdatabase.h>
#include <dbfiler.h>
#include "dbdictionary.h"
#include "exsystemservices.h"
#include "exhostappservices.h"
#include "dbgsmanager.h"
#include "rxvariantvalue.h"
#include "gicontextfordbdatabase.h"
//#include "exgsscreendevice.h"
//#include "exgsgdivectorizedevice.h"
//#include "exgsbitmapdevice.h"
#include "rxdynamicmodule.h"
#include "abstractviewpe.h"
#include "keeper.h"
void odgsinitialize();
using namespace system;
using namespace system::componentmodel;
using namespace system::collections;
using namespace system::windows::forms;
using namespace system::data;
using namespace system::drawing;
namespace simplegdi {
keeper mykeeper;
public ref class acadwingdicontrol : windows::forms::control {
public:
acadwingdicontrol() {
this->backcolor = drawing::color::lightblue;
//windows::forms::messagebox::show(((odint32)this->handle.toint32()).tostring());
}

virtual void onhandlecreated(system::eventargs^ e) override {
control:nhandlecreated(e);
try{
mykeeper.hostappservices = odrxobjectimpl<exhostappservices>::createobject();
mykeeper.systemservices = odrxobjectimpl<exsystemservices>::createobject();
odinitialize(mykeeper.systemservices);
mykeeper.pgs = :drxdynamiclinker()->loadmodule(l"wingdi.gs");
odgsinitialize();
if (mykeeper.pgs.isnull()) {
throw gcnew exception("error loading module");
}
mykeeper.pdb = mykeeper.hostappservices->readfile(l"d:\\muster.dxf");
if (mykeeper.pdb.isnull()) {
throw gcnew exception("error opening database");
}
mykeeper.m_pdevice = mykeeper.pgs->createdevice();
if (mykeeper.m_pdevice.isnull()) {
throw gcnew exception("error creating gdi render device");
}
odrxdictionaryptr pproperties = mykeeper.m_pdevice->properties();
pproperties->putat(l"windowhwnd",odrxvariantvalue( (odint32)this->handle.toint32() ));

odgicontextfordbdatabaseptr pdwgcontext = odgicontextfordbdatabase::createobject();
pdwgcontext->setdatabase(mykeeper.pdb);
mykeeper.m_pdevice = oddbgsmanager::setupactivelayoutviews(mykeeper.m_pdevice,pdwgcontext);
odgsdcrect outputrect( odgsdcpoint(0, 0), odgsdcpoint(100, 100) );
mykeeper.m_pdevice->onsize(outputrect);
odgsview* pview = mykeeper.m_pdevice->viewat(0);
odabstractviewpeptr(pview)->zoomextents(pview);
}catch( oderror e ){
odstring err = e.description();
}
}
virtual void ondoubleclick( system::eventargs^ e ) override {
control:ndoubleclick(e);
if( !mykeeper.m_pdevice.isnull() ){
mykeeper.m_pdevice->update();
}
}
~acadwingdicontrol() {
}
};
}this is the class i keep the relevant objects in:
code:
#pragma once
namespace simplegdi {
public class keeper {
public:
odgsdeviceptr m_pdevice;
oddbdatabaseptr pdb;
odsmartptr<exsystemservices> systemservices;
odsmartptr<exhostappservices> hostappservices;
odgsmoduleptr pgs;
};
};the error message when m_pdevice->update() is called:
quote:
an unhandled exception of type 'system.accessviolationexception' occurred in simplegdi.exe
additional information: attempted to read or write protected memory. this is often an indication that other memory is corrupt.
the call stack:
code:
wingdi_2.06_9.gs!04878769()
[frames below may be incorrect and/or missing, no symbols loaded for wingdi_2.06_9.gs]
wingdi_2.06_9.gs!0488cb55()
wingdi_2.06_9.gs!0488cd10()
dd_gs_2.06_9.dll!0145c802()
dd_db_2.06_9.dll!0086e30e()
[external code]
> simplegdi.exe!simplegdi::acadwingdicontrol:ndoubleclick(system::eventargs^ e = 0x02485c20) line 90 c++
[external code]
user32.dll!77d48734()
user32.dll!77d48816()
user32.dll!77d489cd()
simplegdi.exe!main(array<system::string^> ^ args = {length=0}) line 16 c++
mscoree.dll!7900b1b3()
kernel32.dll!7c816d4f()can the device draw into a windows forms control? is this a matter of managed/unmanaged code or am i ignoring some important dwgdirect rules?
please don't let me hang here. any help is welcome. thanks
martin
you may try to build the project with debug dlls, and turn on unmanaged debugging - that will at least give us proper call stack.
vladimir
yes, i definitely may want to do that... i was using the release dlls, no excuse for that. as for turning on unmanaged debugging -> i switched from "auto" to "mixed", can't tell if that helped.
here is the call stack:
code:
> wingdi_2.06_9.gs!exgigdigeometry::beginpaint(hdc__ * htargetdc=0x0f010427) line 221 + 0xb bytes c++
wingdi_2.06_9.gs!exgsgdivectorizedevice::beginpaint() line 208 c++
wingdi_2.06_9.gs!exgsgdivectorizedevice::updatescreen() line 249 c++
dd_gs_2.06_9.dll!odgsbasevectorizedevice::update(odgsdcrect * prect=0x00000000) line 391 + 0x12 bytes c++
wingdi_2.06_9.gs!exgsgdivectorizedevice::update(odgsdcrect * pupdatedrect=0x00000000) line 269 c++
dd_db_2.06_9.dll!odgsmodellayouthelperimpl::update(odgsdcrect * pupdatedrect=0x00000000) line 718 + 0x21 bytes c++
[external code]
simplegdi.exe!simplegdi::acadwingdicontrol:npaint(system::windows::forms:ainteventargs^ e = 0x0247d3b8) line 122 + 0x29 bytes c++
[external code]
user32.dll!77d48734()
[frames below may be incorrect and/or missing, no symbols loaded for user32.dll]
user32.dll!77d48816()
user32.dll!77d4b4c0()
user32.dll!77d4b50c()
user32.dll!77d4b530()
simplegdi.exe!main(array<system::string^> ^ args = {length=0}) line 16 c++
mscoree.dll!7900b1b3()
kernel32.dll!7c816d4f()and here is a new version of my code. user "than" gave me parts of his solution he found 2 years ago. that was very nice of him, thanks again. to give you the context:
i define my own control, inherited from system::windows::forms::control and am overwriting its onpaint methode in order to get to the graphics-object which comes in the painteventargs. there i get the handle to the hdc and pass it on to the device. on device->update() i get the access violation.
code:
virtual void onpaint(system::windows::forms:ainteventargs^ e) override{
control:npaint(e);
try{
if( !mykeeper.m_pdevice.isnull() ){
// "g" is an instance of system::drawing::graphics
intptr hdc = e->graphics->gethdc();
odint32 handlevalue = (odint32)hdc.toint32();
odrxdictionaryptr pproperties = mykeeper.m_pdevice->properties();
if (pproperties->has(dd_t("windowhdc"))){
pproperties->putat(dd_t("windowhdc"), odrxvariantvalue(handlevalue));
}
if (pproperties->has(dd_t("doublebufferenabled"))){
pproperties->putat(dd_t("doublebufferenabled"), odrxvariantvalue(false));
}
if (pproperties->has(dd_t("clearscreen"))){
pproperties->putat(dd_t("clearscreen"), odrxvariantvalue(false));
}
if (pproperties->has(dd_t("enablesoftwarehlr"))){
pproperties->putat(dd_t("enablesoftwarehlr"), odrxvariantvalue(false));
}
if (pproperties->has(dd_t("discardbackfaces"))){
pproperties->putat(dd_t("discardbackfaces"), odrxvariantvalue(false));
}
mykeeper.m_pdevice = oddbgsmanager::setupactivelayoutviews(mykeeper.m_pdevice, mykeeper.pcontext);
// code to render the drawing
if (! mykeeper.pdb.isnull() && ! mykeeper.m_pdevice.isnull())
{
odgsdcrect gsrect(0, 256, 256, 0); // you'll have to provide the dimensions of the output device
mykeeper.m_pdevice->onsize(gsrect);
mykeeper.m_pdevice->ondisplaychange(16, 256, 256); // same as above
odgsviewptr pview = mykeeper.m_pdevice->viewat(0);
pview->setviewportborderproperties(odrgb(0x00, 0x00, 0x00), 0);
pview->setviewportbordervisibility(false);
pview->setviewport(gsrect);
odabstractviewpeptr(pview)->zoomextents(pview);
pview->setview(pview->position(), pview->target(), pview->upvector() , pview->fieldwidth(), pview->fieldheight(), odgsview::kparallel);
mykeeper.m_pdevice->invalidate();
//if( mykeeper.m_pdevice->isvalid() ){
mykeeper.m_pdevice->update();
//}
}
}
}catch( oderror e ){
odstring err = e.description();
}
}what am i doing wrong? thanks vladimir, i'm really counting on you.
martin
sources for exgigdigeometry::beginpaint are in extensions\exrender\win\exgigdigeometry.cpp
you may place a breakpoint there to see what's wrong.
vladimir
ok, i got it
hello vladimir
while debugging in exgigdigeometry.cpp i found out, that i had not set the logical palette. that's why i got the access violation...
after adding this code...
code:
odcolorref bg = odrgb(255,255,255); // palette background
mykeeper.pcontext->setpalettebackground(bg);
const odcolorref* palette = odcmacadpalette(bg);
mykeeper.m_pdevice->setlogicalpalette(palette, 256);... it finally worked and i saw the drawing displayed in the control!
thank you vladimir, you helped me help myself
now i'll have to catch up for the lost time, highly motivated of course.