前言
大家好，我是小张~
记得小时候，家里只有一个钟表用来看时间(含有时针、分针、秒针的那种)，挂在墙上哒哒哒响个不停，现在生活条件好了、基本人手一部手机，看时间也不再依靠表了，而今天的文章内容就是与这类钟表相关；
本篇文章将用 Python 同时绘制两种类型的表；一个是上面提到的含有时、分、秒针的钟表(为了方便，下面统称为老式钟表)，一个是电子表，最终运行效果如下
环境配置
程序中用到的Python包
<pre spellcheck="false" class="md-fences md-end-block ty-contain-cm modeLoaded" lang="" cid="n9" mdtype="fences" style="box-sizing: border-box; overflow: visible; font-family: var(--monospace); font-size: 0.9em; display: block; break-inside: avoid; text-align: left; white-space: normal; background-image: inherit; background-position: inherit; background-size: inherit; background-repeat: inherit; background-attachment: inherit; background-origin: inherit; background-clip: inherit; background-color: rgb(248, 248, 248); position: relative !important; border: 1px solid rgb(231, 234, 237); border-radius: 3px; padding: 8px 4px 6px; margin-bottom: 15px; margin-top: 15px; width: inherit; color: rgb(51, 51, 51); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">PyQt5
math
sys</pre>
实现思路
实现思路分为大致分为三个部分：老式钟表制作、电子表制作、两表合并为一个界面
老式钟表制作
整体来看老式钟表界面，有以下几种图案：时针、分针、秒针、1-12小时刻度、每格小刻度、每5格一大刻度
在钟表运行时，时针、分针、秒针 随时间变化以界面中心为圆点逆时针旋转一定的角度，这个角度可以计算出来的
为了方便，整个界面效果我用 PyQt5 中的 QPainter 控件来实现，这个控件其实就是一个绘制器，用来绘制界面上的元素
时钟运行轨迹其实就是把每一秒的画面拼接在一起，最后组成一个连贯的时间序列图像，因此重写了 paintEvent 函数，绘制每一秒实时图像；
<pre spellcheck="false" class="md-fences md-end-block ty-contain-cm modeLoaded" lang="" cid="n18" mdtype="fences" style="box-sizing: border-box; overflow: visible; font-family: var(--monospace); font-size: 0.9em; display: block; break-inside: avoid; text-align: left; white-space: normal; background-image: inherit; background-position: inherit; background-size: inherit; background-repeat: inherit; background-attachment: inherit; background-origin: inherit; background-clip: inherit; background-color: rgb(248, 248, 248); position: relative !important; border: 1px solid rgb(231, 234, 237); border-radius: 3px; padding: 8px 4px 6px; margin-bottom: 15px; margin-top: 15px; width: inherit; color: rgb(51, 51, 51); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;"> def paintEvent(self, event):
hour_points = [QPoint(5,8),QPoint(-5,8),QPoint(0,-30)]
minute_points = [QPoint(5,8),QPoint(-5,8),QPoint(0,-65)]
second_points = [QPoint(5,8),QPoint(-5,8),QPoint(0,-80)]
hour_color = QColor(200,100,0,200)
minute_color = QColor(0,127,127,150)
second_color = QColor(0,160,230,150)
min_len = min(self.width(),self.height())
time = QTime.currentTime() #获取当前时间
painter = QPainter(self)
painter.setRenderHint(QPainter.Antialiasing)
painter.translate(self.width()/2,self.height()/2)#平移到窗口中心
painter.scale(min_len/200.0,min_len/200.0) #进行尺度缩放
----------绘制时针------------
painter.setPen(Qt.NoPen)
painter.setBrush(hour_color)#颜色
painter.save()
根据 1小时时= 30°，水品方向逆时针旋转时针
painter.rotate(30.0*((time.hour()+time.minute()/60.0)))
painter.drawConvexPolygon(QPolygon(hour_points))
painter.restore() # save 退出，可重新设置画笔
painter.setPen(hour_color)
绘制小时线(360/12 = 30度)
for i in range(12):
painter.drawLine(88,0,96,0)#绘制水平线
painter.rotate(30.0)# 原有旋转角度上进行旋转；
radius = 100 # 半径
font = painter.font()
font.setBold(True)
painter.setFont(font)
pointSize = font.pointSize()#字体大小
print(pointSize)
绘制小时文本
for i in range(12):
nhour = i + 3 # 从水平 3 点进行绘制
if(nhour>12):
nhour -= 12
painter.drawText(self.textRectF(radius0.8,pointSize,i30),Qt.AlignCenter,str(nhour))
绘制分针;
painter.setPen(Qt.NoPen)
painter.setBrush(minute_color)
painter.save()
1分钟为6°，
painter.rotate(6.0*(time.minute()+time.second()/60.0))
painter.drawConvexPolygon(QPolygon(minute_points))
painter.restore()
绘制分针线
painter.setPen(minute_color)
for i in range(60):
if(i%5 !=0):
painter.drawLine(92,0,96,0)
painter.rotate(6.0)
绘制秒针
painter.setPen(Qt.NoPen)
painter.setBrush(second_color)
painter.save()
绘制秒线
painter.rotate(6.0*time.second())
painter.drawConvexPolygon(QPolygon(second_points))
painter.restore()
painter.setPen(second_color)
for i in range(360):
if(i%5!=0 or i%30!=0):#绘制
painter.drawLine(94,0,96,0)
painter.rotate(1.0)#旋转</pre>
再设置一个时间计时控件，利用信号槽机制连接界面，每一秒更新一次界面
<pre spellcheck="false" class="md-fences md-end-block ty-contain-cm modeLoaded" lang="" cid="n20" mdtype="fences" style="box-sizing: border-box; overflow: visible; font-family: var(--monospace); font-size: 0.9em; display: block; break-inside: avoid; text-align: left; white-space: normal; background-image: inherit; background-position: inherit; background-size: inherit; background-repeat: inherit; background-attachment: inherit; background-origin: inherit; background-clip: inherit; background-color: rgb(248, 248, 248); position: relative !important; border: 1px solid rgb(231, 234, 237); border-radius: 3px; padding: 8px 4px 6px; margin-bottom: 15px; margin-top: 15px; width: inherit; color: rgb(51, 51, 51); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;"> self.timer = QTimer() # 定时器
self.timer.timeout.connect(self.update)
self.timer.start(1000) # 每1s 更新一次</pre>
电子表制作
电子表制作相对要比 老式钟表制作 要简单地多，制作过程中用到 QLCDNumber 控件
QLDNumber 控件用来预览数字，但上面的样式让数字看起来科技感更强，作为电子表预览是非常不错的选择！
使用之前需对该控件的属性做一下微调，例如字体样式，控件内占据字符个数、边框属性等；
<pre spellcheck="false" class="md-fences md-end-block ty-contain-cm modeLoaded" lang="" cid="n27" mdtype="fences" style="box-sizing: border-box; overflow: visible; font-family: var(--monospace); font-size: 0.9em; display: block; break-inside: avoid; text-align: left; white-space: normal; background-image: inherit; background-position: inherit; background-size: inherit; background-repeat: inherit; background-attachment: inherit; background-origin: inherit; background-clip: inherit; background-color: rgb(248, 248, 248); position: relative !important; border: 1px solid rgb(231, 234, 237); border-radius: 3px; padding: 8px 4px 6px; margin-bottom: 15px; margin-top: 15px; width: inherit; color: rgb(51, 51, 51); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">self.lcdNumber = QtWidgets.QLCDNumber(Form)
self.lcdNumber.setGeometry(QtCore.QRect(0, 0, 250, 50))
self.lcdNumber.setContextMenuPolicy(QtCore.Qt.DefaultContextMenu)
self.lcdNumber.setFrameShape(QtWidgets.QFrame.NoFrame)
self.lcdNumber.setSmallDecimalPoint(False)
self.lcdNumber.setDigitCount(8)
self.lcdNumber.setSegmentStyle(QtWidgets.QLCDNumber.Flat)
self.lcdNumber.setProperty("value", 2021.0)
self.lcdNumber.setObjectName("lcdNumber")</pre>
电子表运行效果也是借助于计时控件，每秒更新一次当前界面的时间，但这里没用到 QPainter
<pre spellcheck="false" class="md-fences md-end-block ty-contain-cm modeLoaded" lang="" cid="n29" mdtype="fences" style="box-sizing: border-box; overflow: visible; font-family: var(--monospace); font-size: 0.9em; display: block; break-inside: avoid; text-align: left; white-space: normal; background-image: inherit; background-position: inherit; background-size: inherit; background-repeat: inherit; background-attachment: inherit; background-origin: inherit; background-clip: inherit; background-color: rgb(248, 248, 248); position: relative !important; border: 1px solid rgb(231, 234, 237); border-radius: 3px; padding: 8px 4px 6px; margin-bottom: 15px; margin-top: 15px; width: inherit; color: rgb(51, 51, 51); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;"> self.lcdNumber.display('00:00:00')
time_slot =QTimer(self)
time_slot.setInterval(1000)
time_slot.start()
time_slot.timeout.connect(self.event_1)
time_slot.start(1000)
def event_1(self):
time_format = QTime.currentTime()
time_format = time_format.toString("hh:mm:ss")
self.lcdNumber.display(time_format)
QApplication.processEvents()</pre>
合并两表界面
两个表界面创建完毕之后，最后用一个 Widget 作为基类，利用 Qt 的水平布局把两个表水平拼接在一起，形成了最终的效果
核心代码
<pre spellcheck="false" class="md-fences md-end-block ty-contain-cm modeLoaded" lang="" cid="n34" mdtype="fences" style="box-sizing: border-box; overflow: visible; font-family: var(--monospace); font-size: 0.9em; display: block; break-inside: avoid; text-align: left; white-space: normal; background-image: inherit; background-position: inherit; background-size: inherit; background-repeat: inherit; background-attachment: inherit; background-origin: inherit; background-clip: inherit; background-color: rgb(248, 248, 248); position: relative !important; border: 1px solid rgb(231, 234, 237); border-radius: 3px; padding: 8px 4px 6px; margin-bottom: 15px; margin-top: 15px; width: inherit; color: rgb(51, 51, 51); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;"> self.label1 = Clock_paint()
self.label2 = MyWidget()
self.horizon_layout = QHBoxLayout()
self.horizon_layout.addWidget(self.label1)
self.horizon_layout.addWidget(self.label2)
self.setLayout(self.horizon_layout)
self.setWindowTitle('时钟--《公号:小张Python》')
self.setWindowIcon(QIcon('clock.jpg'))</pre>
总结
本文中的案例算是 PyQt5 的一个小应用，PyQt5 是 Qt 在 Python 语言中的封装，制作 GUI界面时 个人非常推荐这个库，相对于 tk 我更喜欢前者，因为它GUI制作灵活性更强，后续打算出更多小案例来介绍 PyQt5 的相关用法，敬请期待！
好了以上就是本篇文章的全部内容，最后感谢大家的阅读，我们下期见~
源码获取
本文涉及到的源码获取方式，关注微信公号，小张Python，后台回复关键字 210227 即可
