範囲スライダウィジェットからPyQt5への移植

Question

現在、範囲スライダ（最小値と最大値を設定できるスライダ）が必要です。私は2つの関連する質問Range slider in Qt (two handles in a QSlider)とWhy RangeSlider is available in QtQuick and not as standard Widgetを見つけましたが、どちらもpython3で書かれておらず、私はC++に慣れていません。

私はこの完璧なギターツールhttps://github.com/rsgalloway/qrangesliderを見つけましたが、残念ながらPyQt4用に書かれていて、私はPyQt5を使用しています。

このgithubソースをPyQt5バインディングで再フォーマットする予定ですが、その前に誰かがそれを行っているかどうかを知りたいので、時間を節約できますか？ 誰かが別の解決策を持っている場合は、私は提案に開放されています。

Answer 1

以下はQRangeSlider widgetのPyQt5ポートです。簡潔にするために、私はすべてのコメント、doc-strings、assert文などを削除しました。Python 2とPython 3の両方でうまくいくようですが、実際にはそれほど多くはテストしていません。

qrangeslider.py：

import sys, os 
from PyQt5 import QtCore, QtGui, QtWidgets 

__all__ = ['QRangeSlider'] 

DEFAULT_CSS = """ 
QRangeSlider * { 
    border: 0px; 
    padding: 0px; 
} 
QRangeSlider #Head { 
    background: #222; 
} 
QRangeSlider #Span { 
    background: #393; 
} 
QRangeSlider #Span:active { 
    background: #282; 
} 
QRangeSlider #Tail { 
    background: #222; 
} 
QRangeSlider > QSplitter::handle { 
    background: #393; 
} 
QRangeSlider > QSplitter::handle:vertical { 
    height: 4px; 
} 
QRangeSlider > QSplitter::handle:pressed { 
    background: #ca5; 
} 
""" 

def scale(val, src, dst): 
    return int(((val - src[0])/float(src[1]-src[0])) * (dst[1]-dst[0]) + dst[0]) 


class Ui_Form(object): 
    def setupUi(self, Form): 
     Form.setObjectName("QRangeSlider") 
     Form.resize(300, 30) 
     Form.setStyleSheet(DEFAULT_CSS) 
     self.gridLayout = QtWidgets.QGridLayout(Form) 
     self.gridLayout.setContentsMargins(0, 0, 0, 0) 
     self.gridLayout.setSpacing(0) 
     self.gridLayout.setObjectName("gridLayout") 
     self._splitter = QtWidgets.QSplitter(Form) 
     self._splitter.setMinimumSize(QtCore.QSize(0, 0)) 
     self._splitter.setMaximumSize(QtCore.QSize(16777215, 16777215)) 
     self._splitter.setOrientation(QtCore.Qt.Horizontal) 
     self._splitter.setObjectName("splitter") 
     self._head = QtWidgets.QGroupBox(self._splitter) 
     self._head.setTitle("") 
     self._head.setObjectName("Head") 
     self._handle = QtWidgets.QGroupBox(self._splitter) 
     self._handle.setTitle("") 
     self._handle.setObjectName("Span") 
     self._tail = QtWidgets.QGroupBox(self._splitter) 
     self._tail.setTitle("") 
     self._tail.setObjectName("Tail") 
     self.gridLayout.addWidget(self._splitter, 0, 0, 1, 1) 
     self.retranslateUi(Form) 
     QtCore.QMetaObject.connectSlotsByName(Form) 

    def retranslateUi(self, Form): 
     _translate = QtCore.QCoreApplication.translate 
     Form.setWindowTitle(_translate("QRangeSlider", "QRangeSlider")) 


class Element(QtWidgets.QGroupBox): 
    def __init__(self, parent, main): 
     super(Element, self).__init__(parent) 
     self.main = main 

    def setStyleSheet(self, style): 
     self.parent().setStyleSheet(style) 

    def textColor(self): 
     return getattr(self, '__textColor', QtGui.QColor(125, 125, 125)) 

    def setTextColor(self, color): 
     if type(color) == tuple and len(color) == 3: 
      color = QtGui.QColor(color[0], color[1], color[2]) 
     elif type(color) == int: 
      color = QtGui.QColor(color, color, color) 
     setattr(self, '__textColor', color) 

    def paintEvent(self, event): 
     qp = QtGui.QPainter() 
     qp.begin(self) 
     if self.main.drawValues(): 
      self.drawText(event, qp) 
     qp.end() 


class Head(Element): 
    def __init__(self, parent, main): 
     super(Head, self).__init__(parent, main) 

    def drawText(self, event, qp): 
     qp.setPen(self.textColor()) 
     qp.setFont(QtGui.QFont('Arial', 10)) 
     qp.drawText(event.rect(), QtCore.Qt.AlignLeft, str(self.main.min())) 


class Tail(Element): 
    def __init__(self, parent, main): 
     super(Tail, self).__init__(parent, main) 

    def drawText(self, event, qp): 
     qp.setPen(self.textColor()) 
     qp.setFont(QtGui.QFont('Arial', 10)) 
     qp.drawText(event.rect(), QtCore.Qt.AlignRight, str(self.main.max())) 


class Handle(Element): 
    def __init__(self, parent, main): 
     super(Handle, self).__init__(parent, main) 

    def drawText(self, event, qp): 
     qp.setPen(self.textColor()) 
     qp.setFont(QtGui.QFont('Arial', 10)) 
     qp.drawText(event.rect(), QtCore.Qt.AlignLeft, str(self.main.start())) 
     qp.drawText(event.rect(), QtCore.Qt.AlignRight, str(self.main.end())) 

    def mouseMoveEvent(self, event): 
     event.accept() 
     mx = event.globalX() 
     _mx = getattr(self, '__mx', None) 
     if not _mx: 
      setattr(self, '__mx', mx) 
      dx = 0 
     else: 
      dx = mx - _mx 
     setattr(self, '__mx', mx) 
     if dx == 0: 
      event.ignore() 
      return 
     elif dx > 0: 
      dx = 1 
     elif dx < 0: 
      dx = -1 
     s = self.main.start() + dx 
     e = self.main.end() + dx 
     if s >= self.main.min() and e <= self.main.max(): 
      self.main.setRange(s, e) 


class QRangeSlider(QtWidgets.QWidget, Ui_Form): 
    endValueChanged = QtCore.pyqtSignal(int) 
    maxValueChanged = QtCore.pyqtSignal(int) 
    minValueChanged = QtCore.pyqtSignal(int) 
    startValueChanged = QtCore.pyqtSignal(int) 
    minValueChanged = QtCore.pyqtSignal(int) 
    maxValueChanged = QtCore.pyqtSignal(int) 
    startValueChanged = QtCore.pyqtSignal(int) 
    endValueChanged = QtCore.pyqtSignal(int) 

    _SPLIT_START = 1 
    _SPLIT_END = 2 

    def __init__(self, parent=None): 
     super(QRangeSlider, self).__init__(parent) 
     self.setupUi(self) 
     self.setMouseTracking(False) 
     self._splitter.splitterMoved.connect(self._handleMoveSplitter) 
     self._head_layout = QtWidgets.QHBoxLayout() 
     self._head_layout.setSpacing(0) 
     self._head_layout.setContentsMargins(0, 0, 0, 0) 
     self._head.setLayout(self._head_layout) 
     self.head = Head(self._head, main=self) 
     self._head_layout.addWidget(self.head) 
     self._handle_layout = QtWidgets.QHBoxLayout() 
     self._handle_layout.setSpacing(0) 
     self._handle_layout.setContentsMargins(0, 0, 0, 0) 
     self._handle.setLayout(self._handle_layout) 
     self.handle = Handle(self._handle, main=self) 
     self.handle.setTextColor((150, 255, 150)) 
     self._handle_layout.addWidget(self.handle) 
     self._tail_layout = QtWidgets.QHBoxLayout() 
     self._tail_layout.setSpacing(0) 
     self._tail_layout.setContentsMargins(0, 0, 0, 0) 
     self._tail.setLayout(self._tail_layout) 
     self.tail = Tail(self._tail, main=self) 
     self._tail_layout.addWidget(self.tail) 
     self.setMin(0) 
     self.setMax(99) 
     self.setStart(0) 
     self.setEnd(99) 
     self.setDrawValues(True) 

    def min(self): 
     return getattr(self, '__min', None) 

    def max(self): 
     return getattr(self, '__max', None) 

    def setMin(self, value): 
     setattr(self, '__min', value) 
     self.minValueChanged.emit(value) 

    def setMax(self, value): 
     setattr(self, '__max', value) 
     self.maxValueChanged.emit(value) 

    def start(self): 
     return getattr(self, '__start', None) 

    def end(self): 
     return getattr(self, '__end', None) 

    def _setStart(self, value): 
     setattr(self, '__start', value) 
     self.startValueChanged.emit(value) 

    def setStart(self, value): 
     v = self._valueToPos(value) 
     self._splitter.splitterMoved.disconnect() 
     self._splitter.moveSplitter(v, self._SPLIT_START) 
     self._splitter.splitterMoved.connect(self._handleMoveSplitter) 
     self._setStart(value) 

    def _setEnd(self, value): 
     setattr(self, '__end', value) 
     self.endValueChanged.emit(value) 

    def setEnd(self, value): 
     v = self._valueToPos(value) 
     self._splitter.splitterMoved.disconnect() 
     self._splitter.moveSplitter(v, self._SPLIT_END) 
     self._splitter.splitterMoved.connect(self._handleMoveSplitter) 
     self._setEnd(value) 

    def drawValues(self): 
     return getattr(self, '__drawValues', None) 

    def setDrawValues(self, draw): 
     setattr(self, '__drawValues', draw) 

    def getRange(self): 
     return (self.start(), self.end()) 

    def setRange(self, start, end): 
     self.setStart(start) 
     self.setEnd(end) 

    def keyPressEvent(self, event): 
     key = event.key() 
     if key == QtCore.Qt.Key_Left: 
      s = self.start()-1 
      e = self.end()-1 
     elif key == QtCore.Qt.Key_Right: 
      s = self.start()+1 
      e = self.end()+1 
     else: 
      event.ignore() 
      return 
     event.accept() 
     if s >= self.min() and e <= self.max(): 
      self.setRange(s, e) 

    def setBackgroundStyle(self, style): 
     self._tail.setStyleSheet(style) 
     self._head.setStyleSheet(style) 

    def setSpanStyle(self, style): 
     self._handle.setStyleSheet(style) 

    def _valueToPos(self, value): 
     return scale(value, (self.min(), self.max()), (0, self.width())) 

    def _posToValue(self, xpos): 
     return scale(xpos, (0, self.width()), (self.min(), self.max())) 

    def _handleMoveSplitter(self, xpos, index): 
     hw = self._splitter.handleWidth() 
     def _lockWidth(widget): 
      width = widget.size().width() 
      widget.setMinimumWidth(width) 
      widget.setMaximumWidth(width) 
     def _unlockWidth(widget): 
      widget.setMinimumWidth(0) 
      widget.setMaximumWidth(16777215) 
     v = self._posToValue(xpos) 
     if index == self._SPLIT_START: 
      _lockWidth(self._tail) 
      if v >= self.end(): 
       return 
      offset = -20 
      w = xpos + offset 
      self._setStart(v) 
     elif index == self._SPLIT_END: 
      _lockWidth(self._head) 
      if v <= self.start(): 
       return 
      offset = -40 
      w = self.width() - xpos + offset 
      self._setEnd(v) 
     _unlockWidth(self._tail) 
     _unlockWidth(self._head) 
     _unlockWidth(self._handle) 

if __name__ == '__main__': 

    app = QtWidgets.QApplication(sys.argv) 
    rs = QRangeSlider() 
    rs.show() 
    rs.setRange(15, 35) 
    rs.setBackgroundStyle('background: qlineargradient(x1:0, y1:0, x2:0, y2:1, stop:0 #222, stop:1 #333);') 
    rs.handle.setStyleSheet('background: qlineargradient(x1:0, y1:0, x2:0, y2:1, stop:0 #282, stop:1 #393);') 
    app.exec_() 

あなたがexamplesを実行したい場合は、あなただけの（ファイルの先頭に）次のコードブロックを変更する必要があります。

examples.py：

import sys, os 
from PyQt5 import QtCore 
from PyQt5 import QtGui 
from PyQt5 import QtWidgets 

from qrangeslider import QRangeSlider 

app = QtWidgets.QApplication(sys.argv) 

...