BPL BPL - 2 months ago 15
Python Question

How to replace properly certain matches on QScintilla widget?

I got this little mcve code:

import sys
import re

from PyQt5 import QtGui, QtWidgets, QtCore
from PyQt5.QtCore import Qt
from PyQt5.Qsci import QsciScintilla
from PyQt5 import Qsci


class FloatSlider(QtWidgets.QWidget):

value_changed = QtCore.pyqtSignal(float)

def __init__(self, value=0.0, parent=None):
super().__init__(parent)

self.slider = QtWidgets.QSlider(Qt.Horizontal)
self.label = QtWidgets.QLabel()
self.label.setAlignment(Qt.AlignCenter)

self.adjust(value)

layout = QtWidgets.QHBoxLayout()
layout.addWidget(self.slider)
layout.addWidget(self.label)

self.slider.valueChanged.connect(self.on_value_changed)
self.setLayout(layout)
self.setWindowTitle("Adjust number")

def adjust(self, value):
width = 100 # TODO: Adjust it properly depending on input value
self.slider.setRange(value - width, value + width)
self.slider.setSingleStep(1)
self.slider.setValue(value)
self.label.setText(str(float(value)))

def on_value_changed(self, value):
# vmax, vmin = self.slider.minimum(), self.slider.maximum()
# value = 2 * value / (vmax - vmin)
self.label.setText(str(float(value)))
self.value_changed.emit(value)


class SimpleEditor(QsciScintilla):

def __init__(self, language=None, parent=None):
super().__init__(parent)

self.slider = FloatSlider(value=0.0)
self.slider.value_changed.connect(self.float_value_changed)

font = QtGui.QFont()
font.setFamily('Courier')
font.setFixedPitch(True)
font.setPointSize(10)
self.setFont(font)
self.setMarginsFont(font)
fontmetrics = QtGui.QFontMetrics(font)
self.setMarginsFont(font)
self.setMarginWidth(0, fontmetrics.width("00000") + 6)
self.setMarginLineNumbers(0, True)
self.setMarginsBackgroundColor(QtGui.QColor("#cccccc"))
self.setBraceMatching(QsciScintilla.SloppyBraceMatch)
self.setCaretLineVisible(True)
self.setCaretLineBackgroundColor(QtGui.QColor("#E8E8FF"))

if language:
self.lexer = getattr(Qsci, 'QsciLexer' + language)()
self.setLexer(self.lexer)

self.SendScintilla(QsciScintilla.SCI_FOLDALL, True)
self.setAutoCompletionThreshold(1)
self.setAutoCompletionSource(QsciScintilla.AcsAPIs)
self.setFolding(QsciScintilla.BoxedTreeFoldStyle)

# Signals/Slots
self.cursorPositionChanged.connect(self.on_cursor_position_changed)
self.copyAvailable.connect(self.on_copy_available)
self.indicatorClicked.connect(self.on_indicator_clicked)
self.indicatorReleased.connect(self.on_indicator_released)
self.linesChanged.connect(self.on_lines_changed)
self.marginClicked.connect(self.on_margin_clicked)
self.modificationAttempted.connect(self.on_modification_attempted)
self.modificationChanged.connect(self.on_modification_changed)
self.selectionChanged.connect(self.on_selection_changed)
self.textChanged.connect(self.on_text_changed)
self.userListActivated.connect(self.on_user_list_activated)

def float_value_changed(self, v):
print(v)

def on_cursor_position_changed(self, line, index):
text = self.text(line)
for match in re.finditer('(?:^|(?<=\W))\d+(?:\.\d+)?(?=$|\W)', text):
start, end = match.span()
if start <= index <= end:
pos = self.positionFromLineIndex(line, start)
x = self.SendScintilla(
QsciScintilla.SCI_POINTXFROMPOSITION, 0, pos)
y = self.SendScintilla(
QsciScintilla.SCI_POINTYFROMPOSITION, 0, pos)
point = self.mapToGlobal(QtCore.QPoint(x, y))
num = float(match.group())
message = 'number: %s' % num

self.slider.setWindowTitle('line: {0}'.format(line))
self.slider.adjust(num)
self.slider.move(point + QtCore.QPoint(0, 20))
self.slider.show()

break

def on_copy_available(self, yes):
print('-' * 80)
print("on_copy_available")

def on_indicator_clicked(self, line, index, state):
print("on_indicator_clicked")

def on_indicator_released(self, line, index, state):
print("on_indicator_released")

def on_lines_changed(self):
print("on_lines_changed")

def on_margin_clicked(self, margin, line, state):
print("on_margin_clicked")

def on_modification_attempted(self):
print("on_modification_attempted")

def on_modification_changed(self):
print("on_modification_changed")

def on_selection_changed(self):
print("on_selection_changed")

def on_text_changed(self):
print("on_text_changed")

def on_user_list_activated(self, id, text):
print("on_user_list_activated")


def show_requirements():
print(sys.version)
print(QtCore.QT_VERSION_STR)
print(QtCore.PYQT_VERSION_STR)

if __name__ == "__main__":
show_requirements()

app = QtWidgets.QApplication(sys.argv)

ex = QtWidgets.QWidget()
hlayout = QtWidgets.QHBoxLayout()
ed = SimpleEditor("JavaScript")

hlayout.addWidget(ed)

ed.setText("""#ifdef GL_ES
precision mediump float;
#endif

#extension GL_OES_standard_derivatives : enable

uniform float time;
uniform vec2 mouse;
uniform vec2 resolution;

void main( void ) {

vec2 st = ( gl_FragCoord.xy / resolution.xy );
vec2 lefbot = step(vec2(0.1), st);
float pct = lefbot.x*lefbot.y;
vec2 rigtop = step(vec2(0.1), 1.-st);
pct *= rigtop.x*rigtop.y;
vec3 color = vec3(pct);

gl_FragColor = vec4( color, 1.0 );""")

ex.setLayout(hlayout)
ex.show()
ex.resize(800, 600)

sys.exit(app.exec_())


There are several issues I don't know how to address:


  • My slider widget is changing the widget width every time I change values, I tried
    addStrecht(1)
    but it didn't work as I intended as there was too much empty space between widgets (ie: layout arrangement -> slider|strecht|label)

  • Once I type a numeric value on the QScintilla widget the FloatSlider widget will appear and that's definitely something I don't want. I'd like it to appear only when I press such numeric value with the left mouse button or any other combination (ie: ctrl+left_mouse)

  • I don't know how to replace properly the QScintilla text (regex match) on realtime. Ideally only the QScintilla matched text should be modified, for instance, I don't want to replace the whole text because the visual effect would be quite creepy



It didn't feel like opening 3 different questions for these little doubts was ok so I've decided to gather them in the same thread. Hopefully that's ok

BPL BPL
Answer
  • Use setFixedWidth to avoid either the slider or label changing width on every change
  • You shouldn't use on_cursor_position_changed event, instead just use mouseReleaseEvent
  • A good way to replace certain matches at certain position would be instead using setText using insertAt and SCI_DELETERANGE methods. For more information check QScintilla docs