U++ framework: UppHub » RasterCtrl - Opening image using StringStream

Home » Developing U++ » UppHub » RasterCtrl - Opening image using StringStream

Show: Today's Messages :: Polls :: Message Navigator
E-mail to friend

RasterCtrl - Opening image using StringStream [message #55404]

Sat, 07 November 2020 15:25

Runik
Messages: 5
Registered: February 2013
Location: France

Promising Member

Hello,

I've been toying around with RasterCtrl to display a huge image stored as a string in a Sqlite database.
Current implementation opens a file using its path through the file selector, but I wanted to be able to open the saved string directly.
So I created a new private function with the shared code named OpenCommon()

bool RasterCtrl::OpenCommon(){
	if(!raster)
		return false;
	
	// loads pages in array of memoryrasters
	pages.Clear();
	for(curPage = 0; curPage < raster->GetPageCount(); curPage++)
	{
		raster->SeekPage(curPage);
		pages.Add().Load(*raster);
	}
	curPage = 0;
	
	// signals that stream is opened
	isOpened = true;
	
	// if multipage, shows thumbnails, otherwise not
	if(raster->GetPageCount() > 1)
		ShowThumbnails(true);
	else
		ShowThumbnails(false);
	
	// signal page changed to thumbs and view
	thumbs->Layout();
	view->Layout();
	
	return true;
} // END RasterCtrl::OpenCommon()

And I overloaded the current Open() function to load the data from the StringStream :

///////////////////////////////////////////////////////////////////////////////////////////////
// opens an image file in control
bool RasterCtrl::Open(String const &fileName)
{
	// if already opened, closes current stream
	if(isOpened)
		Close();
	
	// opens file and associate to raster
	if(!imageStream.Open(fileName))
		return false;
	raster = StreamRaster::OpenAny(imageStream);
	
	return OpenCommon();
	
} // END RasterCtrl::Open()

bool RasterCtrl::Open(StringStream& str)
{
	// if already opened, closes current stream
	if(isOpened)
		Close();
	
	raster = StreamRaster::OpenAny(str);
	
	return OpenCommon();
	
} // END RasterCtrl::Open()

Nothing fancy Very Happy