用PyQt实现透明桌面时钟小部件

#coding=utf-8
'''
 
'''

import sys
from PyQt4 import  QtGui, QtCore  
from PyQt4.QtCore import Qt
from PyQt4.QtCore import QPoint
from PyQt4.QtCore import QTimer
from PyQt4.QtCore import QTime 
from PyQt4.QtGui import QPainter
from PyQt4.QtGui import QColor 
from PyQt4.QtGui import QPolygon
from PyQt4.QtCore import SIGNAL as signal


class Clock(QtGui.QWidget):
    '''
    classdocs
    '''


    def __init__(self):
        '''
        Constructor
        '''
        
        super(Clock, self).__init__()  
        
        self.hourColor=QColor(127, 0, 127);
        self.minuteColor=QColor(0, 127, 127, 191)
        self.secondColor=QColor(127, 127,0,120)
        self.initUI()
        self.timer = QTimer()
        self.timer.timeout.connect(self.update)
        self.timer.start(30) 
        self.show() 
        
    def handChange(self):    
        
        self.side = min(self.width(), self.height())
        self.hand=(max(self.side/200,4), max(self.side/100,8), max(self.side/40,30))
        self.hourHand=QPolygon([QPoint(self.hand[0],self.hand[1]),QPoint(-self.hand[0],self.hand[1]),QPoint(0,-self.hand[2])])
        self.minuteHand=QPolygon([QPoint(self.hand[0],self.hand[1]),QPoint(-self.hand[0],self.hand[1]),QPoint(0,-self.hand[2]*2)])
        self.secondHand=QPolygon([QPoint(self.hand[0],self.hand[1]),QPoint(-self.hand[0],self.hand[1]),QPoint(0,-self.hand[2]*3)]) 
    
    def set_transparency(self, enabled):
        if enabled:
            self.setAutoFillBackground(False)
        else:
            self.setAttribute(Qt.WA_NoSystemBackground, False)
        #下面这种方式好像不行
#        pal=QtGui.QPalette()
#        pal.setColor(QtGui.QPalette.Background, QColor(127, 127,10,120))
#        self.setPalette(pal) 
        self.setAttribute(Qt.WA_TranslucentBackground, enabled)
        self.repaint()
   
    def initUI(self):      
 
        self.setGeometry(300, 300, 300, 200)
        self.setWindowTitle('Clock')
        self.handChange()
        self.rightButton=False
        # 下面两个配合实现窗体透明和置顶
        sizeGrip=QtGui.QSizeGrip(self)
        self.setWindowFlags(Qt.FramelessWindowHint|Qt.WindowStaysOnTopHint|Qt.SubWindow ) 
        #self.setMouseTracking(True);
        self.trans=True

        self.set_transparency(True) 

        quitAction = QtGui.QAction(QtGui.QIcon('quit.png'), '&Quit', self)
        self.connect(quitAction,signal("triggered()"),QtGui.qApp.quit)
        backAction = QtGui.QAction( '&Back', self)
        self.connect(backAction,signal("triggered()"),self.backClicked)
        self.popMenu= QtGui.QMenu() 
        self.popMenu.addAction(quitAction) 
        self.popMenu.addAction(backAction) 
  
        
    def resizeEvent(self, e):  
        self.handChange()
        
    def backClicked(self):
        if self.trans == True :
            self.trans = False  
            self.set_transparency(False)
        else: 
            self.trans = True 
            self.set_transparency(True)
        
    def mouseReleaseEvent(self,e): 
        if self.rightButton == True:
            self.rightButton=False
            self.popMenu.popup(e.globalPos())

    def mouseMoveEvent(self, e):
        if e.buttons() & Qt.LeftButton:
            self.move(e.globalPos()-self.dragPos)
            e.accept()
    def mousePressEvent(self, e):
      
        if e.button() == Qt.LeftButton: 
            self.dragPos=e.globalPos()-self.frameGeometry().topLeft() 
            e.accept()
        if e.button() == Qt.RightButton and self.rightButton == False:
            self.rightButton=True
    
    def paintEvent(self, e): 
        time = QTime.currentTime() 
        qp = QPainter()

        qp.begin(self)
        #qp.setRenderHint(QPainter.Antialiasing)  # 开启这个抗锯齿,会很占cpu的!
        qp.translate(self.width() / 2, self.height() / 2) 
        qp.scale(self.side / 200.0, self.side / 200.0)
 
        qp.setPen(QtCore.Qt.NoPen)
        qp.setBrush(self.hourColor)
        qp.save()
        qp.rotate(30.0 * ((time.hour() + time.minute()/ 60.0)))
        qp.drawConvexPolygon(self.hourHand)
        qp.restore()
        
        qp.setPen(self.hourColor)
        for i in range(12): 
            qp.drawLine(88, 0, 96, 0)
            qp.rotate(30.0) 
        
        qp.setPen(QtCore.Qt.NoPen)
        qp.setBrush(self.minuteColor)
        qp.save()
        
        qp.rotate(6.0 * ((time.minute() + (time.second()+time.msec()/1000.0) / 60.0)))
        qp.drawConvexPolygon(self.minuteHand)
        qp.restore()
        
        
        qp.setPen(self.minuteColor)
        for i in range(60): 
            if (i % 5) is not 0:
                qp.drawLine(92, 0, 96, 0)
            qp.rotate(6.0) 
        
        qp.setPen(QtCore.Qt.NoPen)
        qp.setBrush(self.secondColor)
        qp.save()
        qp.rotate(6.0*(time.second()+time.msec()/1000.0))
        qp.drawConvexPolygon(self.secondHand)
        qp.restore() 
        qp.end() 
if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)
    clock = Clock()
    sys.exit(app.exec_())