Integrating Qt with Visual Studio (C++) in Win32Proj -

-


Integrating Qt with Visual Studio (C++) in Win32Proj -

short summary: qt class crashes @ class construction part when calling parent qwidget constructor. error message shows: "first-chance exception @ 0x0048fca9 in myapplication.exe: 0xc0000005: access violation reading location 0x00000000."

details: i'm working on project add together overlay user interface 1 client, much steam has when press "tab+shift" while game play. original application written in visual studio environment without ui stuff, , decide utilize qt job.

since project pretty complex transform qt project .pro file, want utilize qt library (including lib , include folder , utilize in project).

it works fine when write in c language. menu show it's not clickable. seems in order create qt event loop work, have declare custom widget class rather grouping of c functions.

i added qt class project, modify include , lib folder, generate moc file, including in project. compiles when run program, shows error message. tracking code shows constructor fails when tried build qwidget.

i have searched online tutorial tells how work in qt creator or visual studio addin scratch.

solved smi:

the problem initialize qapplication later qwidget gets initialized. adding qapplication before calling constructor fixed problem.

one possible reason qwidget constructor failing have forgot initialize qapplication object. qt documentation says:

for gui application using qt, there exactly 1 qapplication object, no matter whether application has 0, 1, 2 or more windows @ given time.

and also:

since qapplication object much initialization, must created before other objects related user interface created.

visual-studio qt user-interface

Comments

Post a Comment

Popular posts from this blog

How do I check if an insert was successful with MySQLdb in Python? -

-
How do I check if an insert was successful with MySQLdb in Python? - i have code: cursor = conn.cursor() cursor.execute(("insert new_files (videos_id, filename, " "is_processing) values (%s,%s,1)"), (id, filename)) logging.warn("%d", cursor.rowcount) if (cursor.rowcount == 1): logging.info("inserted values %d, %s", id, filename) else: logging.warn("failed insert values %d, %s", id, filename) cursor.close() fun is, cursor.rowcount always one, though updated database create videos_id unique key. is, insert fails because in tests same videos_id going appear (and when check database, nil inserted). whatever reason, rowcount 1 - logging.warn have spits out rowcount of 1. so, question: can utilize rowcount work out if insert went fine? if so, (presumably) doing wrong? otherwise, how check if insert went fine? your code not commit after modifications (your modifications rolled back). should...
Read more

delphi - blogger via idHTTP : error 400 bad request -

-
delphi - blogger via idHTTP : error 400 bad request - i'm trying post blogger using idhttp component, however, i'm getting "http/1.0 400 bad request" error. procedure tform1.button1click(sender: tobject); var request,response,req : tstringlist; auth,blogid : string; begin blogid := '00000000000000000000000'; request := tstringlist.create; response := tstringlist.create; req := tstringlist.create; idhttp1.request.connection := 'keep-alive'; idhttp1.request.contenttype := 'application/x-www-form-urlencoded'; idssliohandlersocket1.ssloptions.method := sslvsslv23; request.clear(); request.values['accounttype'] := 'google'; request.values['email'] := 'xxx@gmail.com'; request.values['passwd'] := 'yyy'; request.values['service'] := 'blogger'; response.text :=idhttp1.post('https://www.google.com/accounts/clientlogin',request); auth := resp...
Read more

postgresql - ERROR: operator is not unique: unknown + unknown -

-
postgresql - ERROR: operator is not unique: unknown + unknown - i have postgis database , have compute new values rows in new column. these values should average of values of several columns. query: insert bdps (da_m) values (avg('da_1'+'da_2'+'da_3'+'da_4'+'da_5'+'da_6'+'da_7')); in query bdps database, da_m new column , da_1 da_7 existing columns have double precision type. da_m created using alter table bdps add together column da_m double precision; i next error: error: operator not unique: unknown + unknown line 2: values (avg('da_1'+'da_2'+'da_3'+'da_4'+'da_5'+'da_6'+'da_7... ^ hint: not take best candidate operator. might need add together explicit type casts. ********** error ********** error: operator not unique: unknown + unknown sql state: 42725 hint: not take best candidate operator. might need add togethe...
Read more