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PyBrowser: a nicer QTextBrowser

Work­ing on some of my per­son­al projects (specif­i­cal­ly KRsN and Not­ty), I have need­ed to make QTextBrows­er act a lit­tle more like a men­sch in a few ways:

  • Since it un­der­stands a lot of HTM­L, why not make it open im­ages ref­er­enced in the tex­t, and fol­low links?
  • Since it can show what is pret­ty much a web page, why not make it use HTTP and what­ev­er as need­ed?
  • Make it print. The helpview­er ex­am­ple has all the need­ed code. So, I stole it.

To achieve these goal­s, I had to dig in­to QMime­Source­Fac­to­ry and QDragOb­jec­t, and it ain't all that pret­ty :-)

Click here for the python file (it's in the pub­lic do­main, do as you wish with it).

Cur­rent prob­lem­s:

  • Slow
  • Very slow
  • Does­n't give close to enough feed­back
  • Should have a cache (it's triv­ial)

If any­one who has bet­ter python kung­fu can help me, I'm a hap­py guy.

The re­sult, in 143 lines of python, count­ing blanks and lit­tle de­mo prog­gie is this:

Source code for pybrowser.py
from qt import *
import urlparse
import traceback
from urllib import urlopen
import time


class  Mime­Fac­to­ry(QMimeSourceFactory):

        current=None

        def  __init__(self,browser):
                QMimeSourceFactory.__init__(self)
                self.browser=browser

        def  da­ta(self,name,context=None):
                if context:
                        return self.data(self.makeAbsolute(name,context))
                res=None
                (local,type,subtype)=self.fetchURL(str(name))
                if type=="image":
                        i=QImage()
                        #If image loading fails, return empty image
                        if not i.loadFromData(local,None):
                                i.create(10,10,8)
                        res=QImageDrag(i)
                else: #Assume it's text
                        res=QTextDrag(local)
                        if subtype=="html":
                                res.setSubtype("html")
                        else:
                                res.setSubtype("plain")
                self.current=res
                return self.current

        def  make­Ab­so­lute(self,name,context):
                return urlparse.urljoin(str(context),str(name))

        def  fetchURL(self,url):
                local=""
                type="text"
                subtype="plain"
                try:
                        remote=urlopen(url)
                        info=remote.info()
                        (type,subtype)=info.gettype().split("/")
                        local=remote.read()
                        l=info.getheader('content-length')
                        if not l:
                                l=0
                        else:
                                l=int(l)
                        print 'size',l

                        p=0
                        c=0
                        bsize=1024
                        while True:
                                self.browser.emit(PYSIGNAL('status'),("Downloading: "\
+url+"(%sKB)"%str(p/1024),)) self.browser.emit(PYSIGNAL('size'),(p,)) if l: self.browser.emit(PYSIGNAL('percent'),((p*100)/l,)) qApp.processEvents() #Lame attempt at making this report about once a second stamp=time.time() c=c+1 buf=remote.read(int(bsize)) delta=time.time()-stamp if delta <.5: #Data coming quickly, get more on each loop bsize=min(bsize*1.25,10000) elif delta >.75: #Data coming slowly, get less on each loop bsize=max(bsize*.75,100) #End of file if buf=='': self.browser.emit(PYSIGNAL('percent'),(100,)) break p=p+len(buf) local=local+buf except: traceback.print_exc() return (local,type,subtype) def print­Page(self): printer=QPrinter(QPrinter.HighResolution) printer.setFullPage(True) if printer.setup(self): p=QPainter(printer) if not p.isActive(): # starting printing failed return; metrics=QPaintDeviceMetrics(p.device()) dpiy = metrics.logicalDpiY() margin = int(((2/2.54)*dpiy)) # 2 cm margins body=QRect(margin, margin, metrics.width() - 2*margin, metrics.height()-2*margin) richText=QSimpleRichText( self.viewer.text(), QFont(), self.viewer.context(), self.viewer.styleSheet(), self.viewer.mimeSourceFactory(), body.height() ) richText.setWidth( p, body.width() ) view=QRect(body) page = 1 while True: richText.draw(p,body.left(),body.top(),view,self.colorGroup()) view.moveBy(0,body.height()) p.translate(0,-body.height()) p.drawText(view.right()-p.fontMetrics().width(str(page)), view.bottom()+p.fontMetrics().ascent()+5, str(page)); if view.top() >= richText.height(): break printer.newPage() page+=1 p.end() class QBrows­er(QTextBrowser): def __init__(self,parent=None): QTextBrowser.__init__(self,parent) self.mf=MimeFactory(self) self.setMimeSourceFactory(self.mf) def print­it(arg): print str(arg) if __name__=="__main__": from sys import argv app=QApplication(argv) w=QBrowser() w.connect(w,PYSIGNAL('percent'),printit) w.connect(w,PYSIGNAL('size'),printit) w.connect(w,PYSIGNAL('status'),printit) w.show() w.setSource(argv[1]) app.connect(app, SIGNAL("lastWindowClosed()") , app, SLOT("quit()")) app.exec_loop()
murdoch ravlin / 2007-03-25 17:53:

the
def printPage(self):

does nothing just delete it.

Roberto Alsina / 2007-03-25 19:13:

What do you mean it does nothing? I haven't looked at this code in three years or so, but I'm pretty sure it did something back then :-)

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