Izradite vlastiti program za web preglednik i desktop snimač pomoću PyGobject - 3. dio

Ovo je 3. dio serije o stvaranju GUI aplikacija ispod Linux radne površine pomoću PyGObject. Danas ćemo razgovarati o korištenju nekih naprednih Python modula i knjižnica u našim programima poput ' os ', ' WebKit ', ' zahtjeva ' i drugi, uz neke druge korisne informacije za programiranje.

Morate odavde proći sve ove prethodne dijelove serije da biste nastavili daljnje upute o stvaranju dodatnih aplikacija:

Stvorite GUI aplikacije na Linux radnoj površini pomoću PyGObject - 1. dio
Stvaranje naprednih PyGobject aplikacija na Linuxu - 2. dio

Moduli i knjižnice u Pythonu vrlo su korisni, umjesto da pišete mnoge potprograme za obavljanje nekih složenih poslova koji će vam trebati puno vremena i posla, možete ih jednostavno uvesti! Da, samo uvezite potrebne module i biblioteke u svoj program i moći ćete uštedjeti puno vremena i truda da dovršite svoj program.

Postoje mnogi poznati moduli za Python, koje možete pronaći na Python Module Index.

Možete uvesti i knjižnice za svoj Python program, iz " gi.repository import Gtk " ovaj redak uvozi GTK biblioteku u program Python, postoje mnoge druge knjižnice poput Gdk, WebKit .. itd.

Stvaranje naprednih GUI aplikacija

Danas ćemo stvoriti 2 programa:

Jednostavan web preglednik; koja će koristiti biblioteku WebKit.
Stoni snimač pomoću naredbe ‘avconv’; koji će koristiti modul ‘os’ iz Pythona.

Od sada neću objašnjavati kako povući i ispustiti widgete u dizajneru Glade , već ću vam reći samo ime widgeta koje trebate stvoriti, a dodatno ću vam dati .glade datoteka za svaki program, a sigurno i Python datoteka.

Da bismo stvorili web preglednik, morat ćemo upotrijebiti mehanizam " WebKit ", koji je mehanizam za generiranje otvorenog koda za web, isti je koji se koristi u Chrome / Chromium , za više informacija o njemu možete se obratiti službenom web mjestu Webkit.org.

Prvo ćemo morati stvoriti GUI, otvoriti dizajner Glade i dodati sljedeće widgete. Za više informacija o tome kako stvoriti widgete, slijedite 1. dio i 2. dio ove serije (gore navedene veze).

Izradite widget "window1".
Izradite widget "box1" i "box2".
Izradite widget "button1" i "button2".
Izradite widget ‘entry1’.
Stvorite widget "scrollwindow1".

Nakon izrade dodataka dobit ćete sljedeće sučelje.

Nema ništa novo, osim widgeta " Pomaknuti prozor "; ovaj je widget važan kako bi se omogućilo ugrađivanje mehanizma WebKit u njega, pomoću widgeta "Pomaknuti prozor " moći ćete se pomicati vodoravno i okomito dok pregledavati web stranice.

Morat ćete dodati obrađivač " backbutton_clicked " u signal "kliknuto " gumba Natrag , " refreshbutton_clicked " obrađivač za gumb za osvježavanje " kliknuti signal " i " enterkey_clicked " obrađivač za signal " aktiviran " za unos.

Kompletna datoteka .glade za sučelje je ovdje.

<?xml version="1.0" encoding="UTF-8"?>
<!-- Generated with glade 3.16.1 -->
<interface>
  <requires lib="gtk+" version="3.10"/>
  <object class="GtkWindow" id="window1">
    <property name="can_focus">False</property>
    <property name="title" translatable="yes">Our Simple Browser</property>
    <property name="window_position">center</property>
    <property name="default_width">1000</property>
    <property name="default_height">600</property>
    <property name="icon_name">applications-internet</property>
    <child>
      <object class="GtkBox" id="box1">
        <property name="visible">True</property>
        <property name="can_focus">False</property>
        <property name="orientation">vertical</property>
        <child>
          <object class="GtkBox" id="box2">
            <property name="visible">True</property>
            <property name="can_focus">False</property>
            <child>
              <object class="GtkButton" id="button1">
                <property name="label">gtk-go-back</property>
                <property name="visible">True</property>
                <property name="can_focus">True</property>
                <property name="receives_default">True</property>
                <property name="relief">half</property>
                <property name="use_stock">True</property>
                <property name="always_show_image">True</property>
                <signal name="clicked" handler="backbutton_clicked" swapped="no"/>
              </object>
              <packing>
                <property name="expand">False</property>
                <property name="fill">True</property>
                <property name="position">0</property>
              </packing>
            </child>
            <child>
              <object class="GtkButton" id="button2">
                <property name="label">gtk-refresh</property>
                <property name="visible">True</property>
                <property name="can_focus">True</property>
                <property name="receives_default">True</property>
                <property name="relief">half</property>
                <property name="use_stock">True</property>
                <property name="always_show_image">True</property>
                <signal name="clicked" handler="refreshbutton_clicked" swapped="no"/>
              </object>
              <packing>
                <property name="expand">False</property>
                <property name="fill">True</property>
                <property name="position">1</property>
              </packing>
            </child>
            <child>
              <object class="GtkEntry" id="entry1">
                <property name="visible">True</property>
                <property name="can_focus">True</property>
                <signal name="activate" handler="enterkey_clicked" swapped="no"/>
              </object>
              <packing>
                <property name="expand">True</property>
                <property name="fill">True</property>
                <property name="position">2</property>
              </packing>
            </child>
          </object>
          <packing>
            <property name="expand">False</property>
            <property name="fill">True</property>
            <property name="position">0</property>
          </packing>
        </child>
        <child>
          <object class="GtkScrolledWindow" id="scrolledwindow1">
            <property name="visible">True</property>
            <property name="can_focus">True</property>
            <property name="hscrollbar_policy">always</property>
            <property name="shadow_type">in</property>
            <child>
              <placeholder/>
            </child>
          </object>
          <packing>
            <property name="expand">True</property>
            <property name="fill">True</property>
            <property name="position">1</property>
          </packing>
        </child>
      </object>
    </child>
  </object>
</interface>

Sada kopirajte gornji kod i zalijepite ga u datoteku " ui.glade " u svojoj matičnoj mapi. Sada stvorite novu datoteku pod nazivom " mywebbrowser.py " i u nju unesite sljedeći kôd, a sve objašnjenje nalazi se u komentarima.

#!/usr/bin/python 
# -*- coding: utf-8 -*- 

## Here we imported both Gtk library and the WebKit engine. 
from gi.repository import Gtk, WebKit 

class Handler: 
  
  def backbutton_clicked(self, button): 
  ## When the user clicks on the Back button, the '.go_back()' method is activated, which will send the user to the previous page automatically, this method is part from the WebKit engine. 
    browserholder.go_back() 

  def refreshbutton_clicked(self, button): 
  ## Same thing here, the '.reload()' method is activated when the 'Refresh' button is clicked. 
    browserholder.reload() 
    
  def enterkey_clicked(self, button): 
  ## To load the URL automatically when the "Enter" key is hit from the keyboard while focusing on the entry box, we have to use the '.load_uri()' method and grab the URL from the entry box. 
    browserholder.load_uri(urlentry.get_text()) 
    
## Nothing new here.. We just imported the 'ui.glade' file. 
builder = Gtk.Builder() 
builder.add_from_file("ui.glade") 
builder.connect_signals(Handler()) 

window = builder.get_object("window1") 

## Here's the new part.. We created a global object called 'browserholder' which will contain the WebKit rendering engine, and we set it to 'WebKit.WebView()' which is the default thing to do if you want to add a WebKit engine to your program. 
browserholder = WebKit.WebView() 

## To disallow editing the webpage. 
browserholder.set_editable(False) 

## The default URL to be loaded, we used the 'load_uri()' method. 
browserholder.load_uri("https://linux-console.net") 

urlentry = builder.get_object("entry1") 
urlentry.set_text("https://linux-console.net") 

## Here we imported the scrolledwindow1 object from the ui.glade file. 
scrolled_window = builder.get_object("scrolledwindow1") 

## We used the '.add()' method to add the 'browserholder' object to the scrolled window, which contains our WebKit browser. 
scrolled_window.add(browserholder) 

## And finally, we showed the 'browserholder' object using the '.show()' method. 
browserholder.show() 
 
## Give that developer a cookie ! 
window.connect("delete-event", Gtk.main_quit) 
window.show_all() 
Gtk.main()

Spremite datoteku i pokrenite je.

$ chmod 755 mywebbrowser.py
$ ./mywebbrowser.py

I ovo ćete dobiti.

Možete potražiti službenu dokumentaciju WebKitGtk kako biste otkrili više mogućnosti.

U ovom ćemo odjeljku naučiti kako pokretati lokalne sistemske naredbe ili skripte ljuske iz datoteke Python pomoću modula ' os ', što će nam pomoći da stvorimo jednostavan snimač zaslona za radnu površinu pomoću naredba ' avconv '.

Otvorite Glade dizajner i stvorite sljedeće widgete:

Izradite widget "window1".
Izradite widget "box1".
Izradite widgete "button1", "button2" i "button3".
Izradite widget ‘entry1’.

Nakon stvaranja gore navedenih widgeta, dobit ćete sučelje ispod.

Evo kompletne datoteke ui.glade .

<?xml version="1.0" encoding="UTF-8"?> 
<!-- Generated with glade 3.16.1 --> 
<interface> 
  <requires lib="gtk+" version="3.10"/> 
  <object class="GtkWindow" id="window1"> 
    <property name="can_focus">False</property> 
    <property name="title" translatable="yes">Our Simple Recorder</property> 
    <property name="window_position">center</property> 
    <property name="default_width">300</property> 
    <property name="default_height">30</property> 
    <property name="icon_name">applications-multimedia</property> 
    <child> 
      <object class="GtkBox" id="box1"> 
        <property name="visible">True</property> 
        <property name="can_focus">False</property> 
        <child> 
          <object class="GtkEntry" id="entry1"> 
            <property name="visible">True</property> 
            <property name="can_focus">True</property> 
          </object> 
          <packing> 
            <property name="expand">False</property> 
            <property name="fill">True</property> 
            <property name="position">0</property> 
          </packing> 
        </child> 
        <child> 
          <object class="GtkButton" id="button1"> 
            <property name="label">gtk-media-record</property> 
            <property name="visible">True</property> 
            <property name="can_focus">True</property> 
            <property name="receives_default">True</property> 
            <property name="use_stock">True</property> 
            <property name="always_show_image">True</property> 
            <signal name="clicked" handler="recordbutton" swapped="no"/> 
          </object> 
          <packing> 
            <property name="expand">True</property> 
            <property name="fill">True</property> 
            <property name="position">1</property> 
          </packing> 
        </child> 
        <child> 
          <object class="GtkButton" id="button2"> 
            <property name="label">gtk-media-stop</property> 
            <property name="visible">True</property> 
            <property name="can_focus">True</property> 
            <property name="receives_default">True</property> 
            <property name="use_stock">True</property> 
            <property name="always_show_image">True</property> 
            <signal name="clicked" handler="stopbutton" swapped="no"/> 
          </object> 
          <packing> 
            <property name="expand">True</property> 
            <property name="fill">True</property> 
            <property name="position">2</property> 
          </packing> 
        </child> 
        <child> 
          <object class="GtkButton" id="button3"> 
            <property name="label">gtk-media-play</property> 
            <property name="visible">True</property> 
            <property name="can_focus">True</property> 
            <property name="receives_default">True</property> 
            <property name="use_stock">True</property> 
            <property name="always_show_image">True</property> 
            <signal name="clicked" handler="playbutton" swapped="no"/> 
          </object> 
          <packing> 
            <property name="expand">True</property> 
            <property name="fill">True</property> 
            <property name="position">3</property> 
          </packing> 
        </child> 
      </object> 
    </child> 
  </object> 
</interface>

Kao i obično, kopirajte gornji kod i zalijepite ga u datoteku " ui.glade " u svom početnom direktoriju, stvorite novu datoteku " myrecorder.py " i unesite sljedeće koda unutar njega (Svaki novi redak objašnjen je u komentarima).

#!/usr/bin/python 
# -*- coding: utf-8 -*- 

## Here we imported both Gtk library and the os module. 
from gi.repository import Gtk 
import os 
        
class Handler: 
  def recordbutton(self, button): 
    ## We defined a variable: 'filepathandname', we assigned the bash local variable '$HOME' to it + "/" + the file name from the text entry box. 
    filepathandname = os.environ["HOME"] + "/" + entry.get_text() 
    
    ## Here exported the 'filepathandname' variable from Python to the 'filename' variable in the shell. 
    os.environ["filename"] = filepathandname 
    
    ## Using 'os.system(COMMAND)' we can execute any shell command or shell script, here we executed the 'avconv' command to record the desktop video & audio. 
    os.system("avconv -f x11grab -r 25 -s `xdpyinfo | grep 'dimensions:'|awk '{print $2}'` -i :0.0 -vcodec libx264 -threads 4 $filename -y & ") 
    
    
  def stopbutton(self, button): 
    ## Run the 'killall avconv' command when the stop button is clicked. 
    os.system("killall avconv") 
    
  def playbutton(self, button): 
  ## Run the 'avplay' command in the shell to play the recorded file when the play button is clicked. 
    os.system("avplay $filename &") 
    
    
## Nothing new here.. We just imported the 'ui.glade' file. 
builder = Gtk.Builder() 
builder.add_from_file("ui.glade") 
builder.connect_signals(Handler()) 

window = builder.get_object("window1") 
entry = builder.get_object("entry1") 
entry.set_text("myrecording-file.avi") 

## Give that developer a cookie ! 
window.connect("delete-event", Gtk.main_quit) 
window.show_all() 
Gtk.main()

Sada pokrenite datoteku primjenom sljedećih naredbi u terminalu.

$ chmod 755 myrecorder.py
$ ./myrecorder.py

I dobili ste svoj prvi stoni snimač.

Više informacija o modulu os možete pronaći u biblioteci Python OS.

I to je to, stvaranje aplikacija za radnu površinu Linuxa nije teško koristiti PyGObject , samo trebate stvoriti GUI, uvesti neke module i povezati Python datoteku s GUI, ni više, ni manje. Mnogo je korisnih vodiča o tome na web mjestu PyGObject:

Jeste li probali stvoriti programe pomoću PyGObject-a? Što mislite o tome? Koje ste programe već razvijali?