Make Pretty GUI Apps Fast with Python-Qt - page 2
A Minimal Window, Signals and Slots
Now let's make a bigger application: a 5-card draw poker game. The beginning is just the same, with the addition of the random module so you can deal cards:
#!/usr/bin/python from PyQt4.QtCore import * from PyQt4.QtGui import * import sys, random class PokerWindow(QMainWindow): def __init__(self): QMainWindow.__init__(self) self.mainWidget = QWidget(self) # dummy to contain the layout manager self.setCentralWidget(self.mainWidget) self.setWindowTitle('Poker')
One difference: the central widget is now a new object named "mainWidget". That's because QMainWindow doesn't give you much control over how objects are laid out in the window. The poker game will be set up as a grid, with the five cards arranged horizontally, ranks and suits vertically (Figure 2).
Creating a separate widget lets you use a grid layout:
self.grid = QGridLayout() self.mainWidget.setLayout(self.grid)
We'll need five cards, each of which has a rank and a suit. We'll also need a list of the ranks and suits:
# The five cards: each has a rank and a suit. self.ranks = [None, None, None, None, None] self.suits = [None, None, None, None, None] # Possible suits: self.suitnames = ["Diamonds", "Spades", "Hearts", "Clubs"] # Possible ranks: self.ranknames = [ "1", "2", "3", "4", "5", "6", "7", "8", "9", "10", "J", "Q", "K", "A" ]
It's time to create the widgets to display the cards, using one QLabel object for each card's rank and another for the suit. Each card will occupy a column of its own, with its rank in row 0 and the suit in row 1.
# Create the labels for the card ranks and suits: for i in range(0, len(self.ranks)) : self.ranks[i] = QLabel() self.grid.addWidget(self.ranks[i], 0, i) self.suits[i] = QLabel("") self.grid.addWidget(self.suits[i], 1, i)
Finally, two buttons at the bottom: a Quit button, plus a button to deal a new hand.
# "Deal" button self.dealbutton = QPushButton("Deal") self.grid.addWidget(self.dealbutton, 2, 0) self.connect(self.dealbutton, SIGNAL('clicked()'), self.dealNewHand) # Quit button quitbutton = QPushButton("Quit") self.grid.addWidget(quitbutton, 2, 4) self.connect(quitbutton, SIGNAL('clicked()'), self, SLOT('close()'))
Of course you'll need a function to deal random cards. Still inside your PokerWindow class:
def dealNewHand(self) : for i in range(0, 5) : rank = random.randint(0, 12); self.ranks[i].setText(self.ranknames[rank]) suit = random.randint(0, 3); self.suits[i].setText(self.suitnames[suit])
And some code to run the app:
if __name__ == '__main__': app = QApplication(sys.argv) win = PokerWindow() win.dealNewHand() win.show() app.exec_()
It looks like Figure 3. Ugly! That won't do!
Solid state disks (SSDs) made a splash in consumer technology, and now the technology has its eyes on the enterprise storage market. Download this eBook to see what SSDs can do for your infrastructure and review the pros and cons of this potentially game-changing storage technology.
- 1Linux Top 3: GNOME 3.12 and New Betas for Ubuntu 14.04 and OpenMandriva Lx 2014.0
- 2Linux Top 3: Linus Lashes out, Linux 3.14 Gets PIE and Ubuntu One is Done.
- 3Linux Top 3: Ubuntu 14.04, Debian Gives Squeeze More Life and Red Hat Goes Atomic
- 4Linux Top 3: RHEL 6.5, Debian 7.2 and EOL for Linux 3.0.x
- 5Linux Top 3: CoreOS, Oracle Enterprise Linux 7 and Ubuntu 14.10