Undefined Reference Error When Using PDF Renderer Example
Added by Josh Lampco over 11 years ago
I am trying to generate PDF's using the libHARU library in conjunction with the Wt Web Toolkit. I am trying to build example code that is provided Wt Widget Gallery (Wt PDF Renderer) that exports a PDF from XHTML.
I am compiling using g (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3 without C++11 features enabled.
The errors that I am getting are as follows:
In function `ReportResource::renderPdf(Wt::WString const&, _HPDF_Doc_Rec*)':
undefined reference to `Wt::Render::WPdfRenderer::WPdfRenderer(_HPDF_Doc_Rec*, _HPDF_Dict_Rec*)'
undefined reference to `Wt::Render::WPdfRenderer::setMargin(double, Wt::WFlags<Wt::Side>)'
undefined reference to `Wt::Render::WPdfRenderer::setDpi(int)'
undefined reference to `Wt::Render::WPdfRenderer::~WPdfRenderer()'
undefined reference to `Wt::Render::WPdfRenderer::~WPdfRenderer()'
I do not understand the reason for this error as I have built and linked the libHARU library and Wt library into my project. Just as a sanity check - In Eclipse IDE, I can right click on the Wt::Render::WPdfRenderer::WPdfRenderer and open the declaration (if you are familiar with the Eclipse IDE) and Eclipse takes me right to the header file for this class. In other words, I can confirm that WpdfRenderer is definitely defined. What is causing the "undefined reference errors"?
Below is the code I am using - just for reference. Like I said it is taken straight from the Widget Gallery example.
namespace {
void error_handler(HPDF_STATUS error_no, HPDF_STATUS detail_no, void *user_data) {
fprintf(stderr, "libharu error: error_no=%04X, detail_no=%d\n",
(unsigned int) error_no, (int) detail_no);
}
}
class ReportResource : public Wt::WResource
{
public:
ReportResource(Wt::WObject *parent = 0)
: Wt::WResource(parent)
{
suggestFileName("cycle-times.pdf");
}
virtual void handleRequest(const Wt::Http::Request& request,
Wt::Http::Response& response)
{
response.setMimeType("application/pdf");
HPDF_Doc pdf = HPDF_New(error_handler, 0);
// Note: UTF-8 encoding (for TrueType fonts) is only available since libharu 2.3.0 !
HPDF_UseUTFEncodings(pdf);
renderReport(pdf);
HPDF_SaveToStream(pdf);
unsigned int size = HPDF_GetStreamSize(pdf);
HPDF_BYTE *buf = new HPDF_BYTE[size];
HPDF_ReadFromStream (pdf, buf, &size);
HPDF_Free(pdf);
response.out().write((char*)buf, size);
delete[] buf;
}
private:
void renderReport(HPDF_Doc pdf) {
renderPdf(Wt::WString::tr("report.example"), pdf);
}
void renderPdf(const Wt::WString& html, HPDF_Doc pdf)
{
HPDF_Page page = HPDF_AddPage(pdf);
HPDF_Page_SetSize(page, HPDF_PAGE_SIZE_A4, HPDF_PAGE_PORTRAIT);
Wt::Render::WPdfRenderer renderer(pdf, page); //The first error occurs at this line.
renderer.setMargin(2.54);
renderer.setDpi(96);
renderer.render(html);
}
};
Replies (3)
RE: Undefined Reference Error When Using PDF Renderer Example - Added by Koen Deforche over 11 years ago
Hey,
It seems that you built Wt without libharu support: there will be a message related to not finding libharu when configuring Wt.
Regards,
koen
RE: Undefined Reference Error When Using PDF Renderer Example - Added by Josh Lampco over 11 years ago
Koen,
Yes that does seem to be the case and I do see libharu libraries not found - set HARU_PREFIX
after running cmake ../
from my build directory. I have libharu installed in /usr/local/lib
. Where do I set the flag for Wt to pick up the libharu libraries? I thought that it should just find them and include them.
Thanks,
Josh
RE: Undefined Reference Error When Using PDF Renderer Example - Added by Wim Dumon over 11 years ago
Run cmake .. -DHARU_PREFIX=/usr/local/
If that does not work, look in CMakeCache.txt to see what was found and what was not found (e.g. headers vs libraries), then check wt/cmake/WtFindHaru.txt to see how Wt checks for these files.
Best regards,
Wim.