C++ Qt: can't find methods of dynamic library -

-

i'm working on application in qt has plug-able. i've looked around while , came upon example plugins in qt: http://doc.qt.digia.com/4.6/tools-echoplugin.html

i've changed little classes. i've added random number generator:

randomgenerator.h:

#ifndef randomnumber_h #define randomnumber_h  class randomnumber { public:     ~randomnumber();     randomnumber();     int getnumber(); };  #endif // randomnumber_h

randomgenerator.cpp:

#include "randomnumber.h" #include <stdio.h> #include <stdlib.h> #include <time.h>  randomnumber::randomnumber() {     srand(time(null)); }  int randomnumber::getnumber(){     return rand() % 20; }

then made small adjustment in plugin:

echoplugin.cpp:

#include <qtgui> #include "randomnumber.h" #include "echoplugin.h"  qstring echoplugin::echo(const qstring &message) {     randomnumber* rn = new randomnumber();     qstring a;     a.setnum(rn->getnumber());     return a; }  q_export_plugin2(echoplugin, echoplugin);

it's simplified version of program i'm working on. other classes , methods of example on given link haven't been altered. when try execute program, same error have own program:

/home/user/qt/v1/echoplugin/echoplugin: symbol lookup error: /home/user/qt/v1/echoplugin/plugins/libechoplugin.so: undefined symbol: _zn12randomnumberc1ev

i ran through c++filt, , said problem lies with

randomnumber::randomnumber()

but can't find error concerning method.

thanks in advance!

edit: time, i've solved problem myself , give explanation programmers encounter same problem.

it's simple solution: if want use code of headers , sourcefiles not in headerfile of interface, have include relative path in .pro-file, , includes both source-files , headerfiles. if wanted use randomnumber class, i'd have add .pro-file of plugin:

headers += ../randomnumber.h sources += ../randomnumber.cpp


Popular posts from this blog

How to calculate SNR of signals in MATLAB? -

-
i've encountered simple, yet fundamental problem on calculating snr: there several signals : s1 = original , pure clean signal without noise. n1 = white gaussian noise going added s1. s2 = s1 + n1 (the noisy signal before performing noise-reduction algorithm) s3 = noise-reduced signal (after performing noise reduction algorithm) n2 = s3 - s1 (the amount of noise after performing noise-reduction algorithm) now want compare snr before , after performing noise-reduction algorithm. which signals should consider snr_before!? s1/n1 or s2/n1 ? which signals should consider snr_after!? s3/n1 or s3/n2 ? which commands or functions should use in matlab in order compute snr_before , snr_after? thanks billion putting time on helping me. what know calculating snr before : snrbeforenoise = mean( signal .^ 2 ) / mean( noise .^ 2 ); and snr after : residual_noise = signal - noise_reduced_signal; snr_after = mean( signal .^ 2 ) / mean( residual_noise .^ 2...
Read more

c# - Attempting to upload to FTP: System.Net.WebException: System error -

-
i have api takes in xml , uploads files based on information in xml. uploads on schedule (also xml), , have tested surrounding , know works. i getting error 40% of time on first file attempt upload in each time cycle (time cycle = 45 minutes files, 30 minutes others). here code upload: try { loggerftp.log("uploading file: " + filename, false); // create request. ftpwebrequest request = (ftpwebrequest)webrequest.create(appsettingsftp.ftpurl + @"/" + filename); request.method = webrequestmethods.ftp.uploadfile; request.timeout = 6000000; //set 100 minutes //request.timeout = -1; //set infinite // add login credentials. request.credentials = new networkcredential(appsettingsftp.ftplogin, appsettingsftp.ftppassword); // grab file contents. streamreader sourcestream = new streamreader(appsettingsftp.uploadfiledirectory + filename); byte[] filecontents = encoding.utf8.getbytes(sourcestream.readtoend()); sourcest...
Read more

ios - UISlider customization: how to properly add shadow to custom knob image -

-
Image
i need place custom knob image shadow uislider. far have image of 38x38, of there region defines shadow of knob. now while using image, when slide knob extreme ends actual knob not able cover end points, hence end points visible under transparent region of knob image this code using customize uislider uiimage *slidebtimg = [uiimage imagenamed:sliderknobimg]; [self.ratingslider setthumbimage:slidebtimg forstate:uicontrolstatenormal]; [self.ratingslider setthumbimage:slidebtimg forstate:uicontrolstatehighlighted]; how can implement custom knob shadow beneath it, covering end points?? look inside uislider.h , there methods let customize slider knob , track needed. (ios 2.0 , above) // lets subclass lay out track , thumb needed - (cgrect)minimumvalueimagerectforbounds:(cgrect)bounds; - (cgrect)maximumvalueimagerectforbounds:(cgrect)bounds; - (cgrect)trackrectforbounds:(cgrect)bounds; - (cgrect)thumbrectforbounds:(cgrect)bounds trackrect:(cgrect)rect value:...
Read more