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Updated: How to reduce QWidget nesting in PyQt code?

Updated Question
I think my original quandary might be a result of the structure of my PyQt app. The way I've approached creating a GUI is to divide the larger widget into smaller pieces, each given their own class until the parts are simple enough. Because of this, I end up with a ton of nesting, as a large widget holds instances of smaller widgets, and those hold their own even smaller widgets. It makes it hard to navigate data around the app.
How should a PyQt app be structured so that it is simple to understand in code and yet has a structure containing very little nesting? I haven't found many examples of this around, so I'm sort of stuck. The code example in my original question shows a pretty good example of the structure I'm currently using, which has a large amount of nesting.
Info on program
The GUI is used to create a set of parameters for running a test. The options in each setting should correspond to a binary number, and all of the binary numbers indicated by each set of options are collected, formed into a single sequence of binary numbers, and passed on. Changes to settings do not have to be carried over between sessions, as each new session will most likely correspond to a new test (and thus a new set of choices for settings).
The basic flow of the app should be that upon opening it, all available settings (about 20 total) are set to their default values. A user can go through and change whatever settings they would like, and once they're done they can press a "Generate" button to gather all of the binary numbers corresponding to the settings and create the command. It would be very helpful to have a live preview of individual bits that updates as settings are changed, which is why updates must be immediate.
Some settings are dependent on other; for instance, Setting A has 4 options, and if option 3 is selected, Setting B should be made visible, otherwise it is invisible.
Original Question
I'm definitely a beginner to PyQt, so I don't quite know if I've worded my question correctly, but here goes. I've got a GUI wherein I'm attempting to take a bunch of different settings, keep track of what number was selected from each setting, and then pass the number up to an object that keeps track of all of the numbers from all of the settings. The trouble is that I don't know the best way to get all the individual settings values up my tree of classes, so to speak. Here's the structure of my GUI so far:
Bottom: individual custom QWidgets, each responsible for a single setting. Each has a signal that fires whenever the value it returns changes.
Middle: a QWidget containing ~7-10 individual settings each. These collect settings into related groups.
Top: a QTabWidget that places each instance of a setting group into an individual tab. This widget also contains an object that should ideally collect all of the settings from individual groups into it.
My question is how do I get the values from the bottom layer signals to the top layer widget? My only idea is to connect all of the signals from those small setting widgets to a signal in the middle layer, and connect the middle layer signal to something in the top layer. This sort of chaining seems crazy, though.
I'm running PyQt5 and Python 3.7.
Here's some stripped down code which hopefully shows what I want to do.
class TabWindow(QTabWidget):
def __init__(self):
super().__init__()
self.tabs = [SettingsGroup1, SettingsGroup2, SettingsGroup3]
self.setting_storage = { # dictionary is where I'd like to store all settings values
# 'setting name': setting value
}
for tab in self.tabs:
self.addTab(tab, 'Example')
class SettingsGroup(QWidget):
def __init__(self):
super().__init__()
# not shown: layout created for widget
self.settings = []
def add_to_group(self, new_setting):
self.settings.append(new_setting)
# not shown: add setting to the layout
class SettingsGroup1(SettingsGroup):
def __init__(self):
super().__init__()
self.add_to_group([Setting1, Setting2, Setting3])
class SettingsGroup2(SettingsGroup):...
class SettingsGroup3(SettingsGroup):...
class Setting(QWidget):
val_signal = pyqtSignal([int], name='valChanged')
def __init__(self, name):
self.val = None
self.name = name
def set_val(self, new_val):
self.val = new_val
self.val_signal.emit(self.val) # <-- the signal I want to pass up
class Setting1(Setting):
def __init__(self, name):
super().__init__(name)
# not shown: create custom setting layout/interface
class Setting2(Setting):...
class Setting3(Setting):...
I use a lot of inheritance (SettingsGroup -> SettingsGroup1, 2, 3) because each subclass will have its own functions and internal dependencies that are unique to it. For each Setting subclass, for instance, there is a different user interface.
Thanks for any help provided!

EDIT: The question has been updated in the meantime, I've added a solution that's more specific at the bottom of this answer.
I feel like this question is slightly "opinion based", but since I've had my share of similar situations I'd like to propose my suggestions. In these situations it's important to understand that there's not one good way to do things, but many ways to do it wrong.
Original answer
An idea could be to create a common signal interface for every "level", which will get that signal and send it back to its parent by adding its own name to keep track of the setting "path"; the topmost widget will then evaluate the changes accordingly.
In this example every tab "group" has its own valueChanged signal, which includes the group name, setting name and value; the source signal is fired from the "source" (a spinbox, in this case), then it follows its parents which, in turn "add" their name in turn.
Keep in mind that you can also just use a generalized pyqtSignal(object) for every parent and connect it with widget.valueChanged.connect(self.valueChanged), and then track its group and setting by walking by self.sender() parents backwards.
As a final notice, if you are using these values for application settings, remember that Qt already provides the QSettings API, which can be used as a common and OS-transparent interface for every configuration you need to set (and remember between sessions) in your application. I implemented it in the example, but I suggest you to read its documentation to better understand how it works.
import sys
from PyQt5 import QtCore, QtWidgets
class SettingWidget(QtWidgets.QWidget):
valueChanged = QtCore.pyqtSignal(int)
def __init__(self, name):
super().__init__()
self.settings = QtCore.QSettings()
self.val = 0
self.name = name
layout = QtWidgets.QVBoxLayout()
self.setLayout(layout)
layout.addWidget(QtWidgets.QLabel(self.name))
self.spinBox = QtWidgets.QSpinBox()
layout.addWidget(self.spinBox)
self.spinBox.valueChanged.connect(self.set_val)
def set_val(self, new_val):
if self.val != new_val:
self.val = new_val
self.valueChanged.emit(self.val)
# enter a setting group, ensuring that same name settings won't
# be mismatched; this allows a single sub level setting only
self.settings.beginGroup(self.parent().name)
self.settings.setValue(self.name, new_val)
# leave the setting group. THIS IS IMPORTANT!!!
self.settings.endGroup()
class SettingWidget1(SettingWidget):
def __init__(self):
super().__init__('Setting1')
class SettingWidget2(SettingWidget):
def __init__(self):
super().__init__('Setting2')
class SettingWidget3(SettingWidget):
def __init__(self):
super().__init__('Setting3')
class SettingsGroup(QtWidgets.QWidget):
# create two signal signatures, the first sends the full "path",
# while the last will just send the value
valueChanged = QtCore.pyqtSignal([str, str, int], [int])
def __init__(self, name):
super().__init__()
self.name = name
layout = QtWidgets.QHBoxLayout()
self.setLayout(layout)
def add_to_group(self, new_setting):
widget = new_setting()
# emit both signal signatures
widget.valueChanged.connect(
lambda value, name=widget.name: self.valueChanged.emit(
self.name, name, value))
widget.valueChanged.connect(self.valueChanged[int])
self.layout().addWidget(widget)
class SettingsGroup1(SettingsGroup):
def __init__(self):
super().__init__('Group1')
self.add_to_group(SettingWidget1)
self.add_to_group(SettingWidget2)
class SettingsGroup2(SettingsGroup):
def __init__(self):
super().__init__('Group2')
self.add_to_group(SettingWidget3)
class TabWidget(QtWidgets.QTabWidget):
def __init__(self):
QtWidgets.QTabWidget.__init__(self)
self.settings = QtCore.QSettings()
self.tabs = [SettingsGroup1, SettingsGroup2]
self.settingsDict = {}
for tab in self.tabs:
widget = tab()
self.addTab(widget, widget.__class__.__name__)
widget.valueChanged[str, str, int].connect(self.valueChangedFullPath)
widget.valueChanged[int].connect(self.valueChangedOnly)
def valueChangedFullPath(self, group, setting, value):
# update the settings dict; if the group key doesn't exist, create it
try:
self.settingsDict[group][setting] = value
except:
self.settingsDict[group] = {setting: value}
settingsData = [group, setting, value]
print('Full path result: {}'.format(settingsData))
# Apply setting from here, instead of using the SettingWidget
# settings.setValue() option; this allows a single sub level only
# self.applySetting(data)
def valueChangedOnly(self, value):
parent = sender = self.sender()
# sender() returns the last signal sender, so we need to track down its
# source; keep in mind that this is *not* a suggested approach, as
# tracking the source might result in recursion if the sender's sender
# is not one of its children; this system also has issues if you're
# using a Qt.DirectConnection from a thread different from the one that
# emitted it
while parent.sender() in sender.children():
parent = sender.sender()
widgetPath = []
while parent not in self.children():
widgetPath.insert(0, parent)
parent = parent.parent()
settingsData = [w.name for w in widgetPath] + [value]
print('Single value result: {}'.format(settingsData))
# similar to valueChangedFullPath(), but with this implementation more
# nested "levels" can be used instead
# self.applySetting(settingsData)
def applySetting(self, settingsData):
# walk up to the next to last of settingsData levels, assuming they are
# all parent group section names
for count, group in enumerate(settingsData[:-2], 1):
self.settings.beginGroup(group)
# set the setting name settingsData[-2] to its value settingsData[-1]
self.settings.setValue(*settingsData[-2:])
for g in range(count):
self.settings.endGroup()
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
# set both Organization and Application name to make settings persistent
app.setOrganizationName('StackOverflow')
app.setApplicationName('Example')
w = TabWidget()
w.show()
sys.exit(app.exec_())
Alternate solution, based on updated answer
Since the answer has become more specific in its update, I'm adding another suggestion.
As far as we can understand now, you don't need that level of "nested" classes, but more specifically designed code that can be reused according to your purposes. Also, since you're using binary based data, it makes things a bit (pun intended) easier, as long as you know how bit operation works (which I assume you do) and the setting "widgets" don't require specific GUI customization.
In this example I created just one "setting" class and one "group" class, and their instancies are created only according to their names and default values.
import sys
from PyQt5 import QtCore, QtWidgets
defaultValues = '0010101', '1001010', '000111'
# set bit lengths for each setting; be careful in ensuring that each
# setting group has the full default value bit length!
groups = [
['Group 1', [1, 3, 2, 1]],
['Group 2', [1, 2, 2, 1, 1]],
['Group 1', [2, 1, 2, 1]],
]
class BinaryWidget(QtWidgets.QFrame):
changed = QtCore.pyqtSignal()
def __init__(self, name, index, defaults='0'):
QtWidgets.QFrame.__init__(self)
self.setFrameShape(self.StyledPanel|self.Sunken)
layout = QtWidgets.QGridLayout()
self.setLayout(layout)
self.index = index
self.defaults = defaults
self.buttons = []
# use the "defaults" length to create buttons
for i in range(len(defaults)):
value = int(defaults[i], 2) & 1
# I used QToolButtons as they're usually smaller than QPushButtons
btn = QtWidgets.QToolButton()
btn.setText(str(value))
layout.addWidget(btn, 1, i)
btn.setCheckable(True)
btn.setChecked(value)
btn.toggled.connect(self.changed)
# show the binary value on change, just for conveniency
btn.toggled.connect(lambda v, btn=btn: btn.setText(str(int(v))))
self.buttons.append(btn)
layout.addWidget(QtWidgets.QLabel(name), 0, 0, 1, layout.columnCount())
def value(self):
# return the correct value of all widget's buttons; they're reversed
# because of how bit shifting works
v = 0
for i, btn in enumerate(reversed(self.buttons)):
v += btn.isChecked() << i
# bit shift again, according to the actual "setting" bit index
return v << self.index
def resetValues(self):
oldValue = self.value()
self.blockSignals(True)
for i, value in enumerate(self.defaults):
self.buttons[i].setChecked(int(self.defaults[i], 2) & 1)
self.blockSignals(False)
newValue = self.value()
# emit the changed signal only once, and only if values actually changed
if oldValue != newValue:
self.changed.emit()
class Group(QtWidgets.QWidget):
changed = QtCore.pyqtSignal()
def __init__(self, name, defaults=None, lenghts=None):
QtWidgets.QWidget.__init__(self)
layout = QtWidgets.QHBoxLayout()
self.setLayout(layout)
self.name = name
self.bitLength = 0
self.widgets = []
if defaults is not None:
self.addOptions(defaults, lenghts)
def value(self):
v = 0
for widget in self.widgets:
v += widget.value()
return v
def addOption(self, name, index, default='0'):
widget = BinaryWidget(name, index, default)
self.layout().addWidget(widget)
self.widgets.append(widget)
widget.changed.connect(self.changed)
self.bitLength += len(default)
def addOptions(self, defaults, lenghts = None):
if lenghts is None:
lenghts = [1] * len(defaults)
# reverse bit order for per-setting indexing
defaultsIndex = 0
bitIndex = len(defaults)
for i, l in enumerate(lenghts):
self.addOption(
'Setting {}'.format(i + 1),
bitIndex - l,
defaults[defaultsIndex:defaultsIndex + l])
bitIndex -= l
defaultsIndex += l
def resetValues(self):
for widget in self.widgets:
widget.resetValues()
class Tester(QtWidgets.QWidget):
def __init__(self):
QtWidgets.QWidget.__init__(self)
layout = QtWidgets.QGridLayout()
self.setLayout(layout)
self.tabWidget = QtWidgets.QTabWidget()
layout.addWidget(self.tabWidget)
resultLayout = QtWidgets.QHBoxLayout()
layout.addLayout(resultLayout, layout.rowCount(), 0, 1, layout.columnCount())
self.tabs = []
self.labels = []
for (group, lenghts), defaults in zip(groups, defaultValues):
tab = Group(group, defaults, lenghts)
self.tabWidget.addTab(tab, group)
tab.changed.connect(self.updateResults)
self.tabs.append(tab)
tabLabel = QtWidgets.QLabel()
self.labels.append(tabLabel)
resultLayout.addWidget(tabLabel)
self.resetButton = QtWidgets.QPushButton('Reset values')
layout.addWidget(self.resetButton)
self.resetButton.clicked.connect(lambda: [tab.resetValues() for tab in self.tabs])
self.updateResults()
def values(self):
return [tab.value() for tab in self.tabs]
def updateResults(self):
for value, tab, label in zip(self.values(), self.tabs, self.labels):
label.setText('''
{0}: <span style="font-family:monospace;">{1} <b>{1:0{2}b}</b></span>
'''.format(tab.name, value, tab.bitLength))
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
w = Tester()
w.show()
sys.exit(app.exec_())

Using click.progressbar with multiprocessing in Python

I have a huge list that I need to process, which takes some time, so I divide it into 4 pieces and multiprocess each piece with some function. It still takes a bit of time to run with 4 cores, so I figured I would add some progress bar to the function, so that it could tell me where each processor is at in processing the list.
My dream was to have something like this:
erasing close atoms, cpu0 [######..............................] 13%
erasing close atoms, cpu1 [#######.............................] 15%
erasing close atoms, cpu2 [######..............................] 13%
erasing close atoms, cpu3 [######..............................] 14%
with each bar moving as the loop in the function progresses. But instead, I get a continuous flow:
etc, filling my terminal window.
Here is the main python script that calls the function:
from eraseCloseAtoms import *
from readPDB import *
import multiprocessing as mp
from vectorCalc import *
prot, cell = readPDB('file')
atoms = vectorCalc(cell)
output = mp.Queue()
# setup mp to erase grid atoms that are too close to the protein (dmin = 2.5A)
cpuNum = 4
tasks = len(atoms)
rangeSet = [tasks / cpuNum for i in range(cpuNum)]
for i in range(tasks % cpuNum):
rangeSet[i] += 1
rangeSet = np.array(rangeSet)
processes = []
for c in range(cpuNum):
na, nb = (int(np.sum(rangeSet[:c] + 1)), int(np.sum(rangeSet[:c + 1])))
processes.append(mp.Process(target=eraseCloseAtoms, args=(prot, atoms[na:nb], cell, 2.7, 2.5, output)))
for p in processes:
p.start()
results = [output.get() for p in processes]
for p in processes:
p.join()
atomsNew = results[0] + results[1] + results[2] + results[3]
Below is the function eraseCloseAtoms():
import numpy as np
import click
def eraseCloseAtoms(protein, atoms, cell, spacing=2, dmin=1.4, output=None):
print 'just need to erase close atoms'
if dmin > spacing:
print 'the spacing needs to be larger than dmin'
return
grid = [int(cell[0] / spacing), int(cell[1] / spacing), int(cell[2] / spacing)]
selected = list(atoms)
with click.progressbar(length=len(atoms), label='erasing close atoms') as bar:
for i, atom in enumerate(atoms):
bar.update(i)
erased = False
coord = np.array(atom[6])
for ix in [-1, 0, 1]:
if erased:
break
for iy in [-1, 0, 1]:
if erased:
break
for iz in [-1, 0, 1]:
if erased:
break
for j in protein:
protCoord = np.array(protein[int(j)][6])
trueDist = getMinDist(protCoord, coord, cell, vectors)
if trueDist <= dmin:
selected.remove(atom)
erased = True
break
if output is None:
return selected
else:
output.put(selected)

accepted answer says it's impossible with click and it'd require 'non trivial amount of code to make it work'.
While it's true, there is another module with this functionality out of the box: tqdm
https://github.com/tqdm/tqdm which does exatly what you need.
You can do nested progress bars in docs https://github.com/tqdm/tqdm#nested-progress-bars etc.

I see two issues in your code.
The first one explains why your progress bars are often showing 100% rather than their real progress. You're calling bar.update(i) which advances the bar's progress by i steps, when I think you want to be updating by one step. A better approach would be to pass the iterable to the progressbar function and let it do the updating automatically:
with click.progressbar(atoms, label='erasing close atoms') as bar:
for atom in bar:
erased = False
coord = np.array(atom[6])
# ...
However, this still won't work with multiple processes iterating at once, each with its own progress bar due to the second issue with your code. The click.progressbar documentation states the following limitation:
No printing must happen or the progress bar will be unintentionally destroyed.
This means that whenever one of your progress bars updates itself, it will break all of the other active progress bars.
I don't think there is an easy fix for this. It's very hard to interactively update a multiple-line console output (you basically need to be using curses or a similar "console GUI" library with support from your OS). The click module does not have that capability, it can only update the current line. Your best hope would probably be to extend the click.progressbar design to output multiple bars in columns, like:
CPU1: [###### ] 52% CPU2: [### ] 30% CPU3: [######## ] 84%
This would require a non-trivial amount of code to make it work (especially when the updates are coming from multiple processes), but it's not completely impractical.

For anybody coming to this later. I created this which seems to work okay. It overrides click.ProgressBar fairly minimally, although I had to override an entire method for only a few lines of code at the bottom of the method. This is using \x1b[1A\x1b[2K to clear the progress bars before rewriting them so may be environment dependent.
#!/usr/bin/env python
import time
from typing import Dict
import click
from click._termui_impl import ProgressBar as ClickProgressBar, BEFORE_BAR
from click._compat import term_len
class ProgressBar(ClickProgressBar):
def render_progress(self, in_collection=False):
# This is basically a copy of the default render_progress with the addition of in_collection
# param which is only used at the very bottom to determine how to echo the bar
from click.termui import get_terminal_size
if self.is_hidden:
return
buf = []
# Update width in case the terminal has been resized
if self.autowidth:
old_width = self.width
self.width = 0
clutter_length = term_len(self.format_progress_line())
new_width = max(0, get_terminal_size()[0] - clutter_length)
if new_width < old_width:
buf.append(BEFORE_BAR)
buf.append(" " * self.max_width)
self.max_width = new_width
self.width = new_width
clear_width = self.width
if self.max_width is not None:
clear_width = self.max_width
buf.append(BEFORE_BAR)
line = self.format_progress_line()
line_len = term_len(line)
if self.max_width is None or self.max_width < line_len:
self.max_width = line_len
buf.append(line)
buf.append(" " * (clear_width - line_len))
line = "".join(buf)
# Render the line only if it changed.
if line != self._last_line and not self.is_fast():
self._last_line = line
click.echo(line, file=self.file, color=self.color, nl=in_collection)
self.file.flush()
elif in_collection:
click.echo(self._last_line, file=self.file, color=self.color, nl=in_collection)
self.file.flush()
class ProgressBarCollection(object):
def __init__(self, bars: Dict[str, ProgressBar], bar_template=None, width=None):
self.bars = bars
if bar_template or width:
for bar in self.bars.values():
if bar_template:
bar.bar_template = bar_template
if width:
bar.width = width
def __enter__(self):
self.render_progress()
return self
def __exit__(self, exc_type, exc_val, exc_tb):
self.render_finish()
def render_progress(self, clear=False):
if clear:
self._clear_bars()
for bar in self.bars.values():
bar.render_progress(in_collection=True)
def render_finish(self):
for bar in self.bars.values():
bar.render_finish()
def update(self, bar_name: str, n_steps: int):
self.bars[bar_name].make_step(n_steps)
self.render_progress(clear=True)
def _clear_bars(self):
for _ in range(0, len(self.bars)):
click.echo('\x1b[1A\x1b[2K', nl=False)
def progressbar_collection(bars: Dict[str, ProgressBar]):
return ProgressBarCollection(bars, bar_template="%(label)s [%(bar)s] %(info)s", width=36)
#click.command()
def cli():
with click.progressbar(length=10, label='bar 0') as bar:
for i in range(0, 10):
time.sleep(1)
bar.update(1)
click.echo('------')
with ProgressBar(iterable=None, length=10, label='bar 1', bar_template="%(label)s [%(bar)s] %(info)s") as bar:
for i in range(0, 10):
time.sleep(1)
bar.update(1)
click.echo('------')
bar2 = ProgressBar(iterable=None, length=10, label='bar 2')
bar3 = ProgressBar(iterable=None, length=10, label='bar 3')
with progressbar_collection({'bar2': bar2, 'bar3': bar3}) as bar_collection:
for i in range(0, 10):
time.sleep(1)
bar_collection.update('bar2', 1)
for i in range(0, 10):
time.sleep(1)
bar_collection.update('bar3', 1)
if __name__ == "__main__":
cli()

It may not be the same as your dream, but you can use imap_unordered with click.progressbar to integrate with multiprocessing.
import multiprocessing as mp
import click
import time
def proc(arg):
time.sleep(arg)
return True
def main():
p = mp.Pool(4)
args = range(4)
results = p.imap_unordered(proc, args)
with click.progressbar(results, length=len(args)) as bar:
for result in bar:
pass
if __name__ == '__main__:
main()

Something like this will work if you are okay with having one progress bar:
import click
import threading
import numpy as np
reallybiglist = []
numthreads = 4
def myfunc(listportion, bar):
for item in listportion:
# do a thing
bar.update(1)
with click.progressbar(length=len(reallybiglist), show_pos=True) as bar:
threads = []
for listportion in np.split(reallybiglist, numthreads):
thread = threading.Thread(target=myfunc, args=(listportion, bar))
thread.start()
threads.append(thread)
for thread in threads:
thread.join()

Best approach to draw and update thousands of QGraphicsRectItem(s) efficiently?

I'm new to Qt (PySide), and I'm trying to draw a 'grid map' efficiently. However my solution slows down to a halt with 10k+ QGraphicsRectItem.
Currently it works like so:
class GridMapView(QObject, QGraphicsItemGroup):
def __init__(self, mapWidth, mapHeight, cellSize):
QObject.__init__(self)
QGraphicsItemGroup.__init__(self)
self.mapWidth = mapWidth
self.mapHeight = mapHeight
self.cellSize = cellSize
self.graphicCells = []
#Create cells.
for x in range(self.mapWidth / self.cellSize):
self.graphicCells.append([])
for y in range(self.mapHeight / self.cellSize):
self.graphicCells[x].append(QGraphicsRectItem(x * self.cellSize, y * self.cellSize, self.cellSize, self.cellSize))
self.graphicCells[x][-1].setBrush(QBrush(QColor('grey')))
self.addToGroup(self.graphicCells[x][-1])
self.setPos(-mapWidth/2, -mapHeight/2)
#Slot(Point, int)
def onCellUpdated(self, index, state):
cell = self.graphicCells[index.x][index.y]
if state == CellStates.UNKNOWN:
cell.setBrush(QBrush(QColor('grey')))
cell.setVisible(True)
elif state == CellStates.FREE:
cell.setVisible(False)
elif state == CellStates.OCCUPIED:
cell.setBrush(QBrush(QColor('black')))
cell.setVisible(True)
The initial grid is populated during creation. When the appropriate signal is fired, a specific cell will be updated. This updating is fairly infrequent, and my assumption was that Qt only draws what changes.
The entire 'map' is visible in my viewport, and disabling the rendering makes my application run perfectly fine.
I've tried setting QGraphicsView.NoViewportUpdate, yet it still updates the entire view. I hoped it would require me to call '.update()'.
Is this approach flawed from the start? Thanks in advance.

Timed Threaded function as an attribute in a class

So I am making a text based adventure game. I am working on the engine right now and I am stuck after long hours searching for a solution for this problem.
I have a class called use_action. One of the arguments for that class is a name of a function. I would like to be able to create this action and have a possible custom function incase the item that calls this use_action does something specific.
The custom function I am working with right now is where the player is hurt and is losing 5 HP every so many seconds.
This should start when he uses a specific item and then stops when he uses the medicine that will link to the stop function. The problem I have is that the function gets called immediately. Even though I am trying to call it at the end of a long if else statement. And then when i get to where i am trying to call it it doesn't call.
I am not posting the whole class as it along with its functions are about 150 lines of code.
class use_action(object):
def __init__(self, function = None):
self.function = function
pizza_act = use_action(function = mechanics.tmr.start())
#This is located at the end of an if else statement after the player types use . . .
if self.function != None:
self.function
else:
pass
From Mechanics:
thread_list = []
class TimerClass(threading.Thread):
def __init__(self, function, time):
threading.Thread.__init__(self)
self.event = threading.Event()
self.function = function
self.time = time
thread_list.append(self)
def run(self):
while not self.event.is_set():
self.event.wait( self.time )
self.function()
def stop(self):
self.event.set()
def blank_current_readline():
# Next line said to be reasonably portable for various Unixes
(rows,cols) = struct.unpack('hh', fcntl.ioctl(sys.stdout, termios.TIOCGWINSZ,'1234'))
text_len = len(readline.get_line_buffer())+2
# ANSI escape sequences (All VT100 except ESC[0G)
sys.stdout.write('\x1b[2K') # Clear current line
sys.stdout.write('\x1b[1A\x1b[2K'*(text_len/cols)) # Move cursor up and clear line
sys.stdout.write('\x1b[0G') # Move to start of line
def pizza_poisoned_action():
# threading.Timer(10, pizza_poisoned_action).start()
blank_current_readline()
print "You lost 5 hp."
initialization.gamer.hp -= 5
sys.stdout.write('> ' + readline.get_line_buffer())
sys.stdout.flush() # Needed or text doesn't show until a key is pressed
tmr = TimerClass(pizza_poisoned_action, 5)
Sorry about the length, I tried to only post the relevant stuff for this. If you think i should post some other piece of code that may be relevant let me know!

If you want to pass a function, don't call it. Or else, you'll be passing the return value.
pizza_act = use_action(function = mechanics.test()) #Wrong!
pizza_act = use_action(function = mechanics.test) #Right

Fix values that are typed into a doublespinbox in PyQt

I want to create a doublespin box that changes values in steps of 0.2. But when the user enters a value that is not correct according to the steps. I normalizes that to the nearest correct value.
I tried something like the code shown below but I don't know how to stop values like 0.5 to be entered. Please help me on this.
from PyQt4.QtCore import *
from PyQt4.QtGui import *
class SigSlot(QWidget):
def __init__(self, parent=None):
QWidget.__init__(self, parent)
self.setWindowTitle('spinbox value')
self.resize(250,150)
self.lcd1 = QLCDNumber(self)
self.spinbox1 = QDoubleSpinBox(self)
self.spinbox1.setSingleStep(0.2)
self.spinbox1.setCorrectionMode(1)
# create a Grid Layout
grid = QGridLayout()
grid.addWidget(self.lcd1, 0, 0)
grid.addWidget(self.spinbox1, 1, 0)
self.setLayout(grid)
# allows access to the spinbox value as it changes
self.connect(self.spinbox1, SIGNAL('valueChanged(double)'), self.change_value1)
def change_value1(self, event):
val = self.spinbox1.value()
self.lcd1.display(val)
app = QApplication([])
qb = SigSlot()
qb.show()
app.exec_()

You have two choices:
You can subclass the QSpinBox, override validate method and use an appropriate Q*Validator (e.g. QRegExpValidator) inside.
You can check the value in slot connected to valueChanged before using and correct it if necessary.
Since you are already using the valueChanged signal, second option should be fairly easy to implement. Just change your change_value method like this:
def change_value1(self, val): # new value is passed as an argument
# so no need for this
# val = self.spinbox1.value()
new_val = round(val*5)/5 # one way to fix
if val != new_val: # if value is changed, put it in the spinbox
self.spinbox1.setValue(new_val)
self.lcd1.display(new_val)
By the way, since you are using only one decimal precision, it might be logical to also use:
self.spinbox1.setDecimals(1)
in your __init__. And try to use the new style signals and slots. i.e.:
self.connect(self.spinbox1, SIGNAL('valueChanged(double)'), self.change_value1)
could be written as:
self.spinbox1.valueChanged[float].connect(self.change_value1)
Edit
Subclassing:
class MySpinBox(QDoubleSpinBox):
def __init__(self, parent=None):
super(MySpinBox, self).__init__(parent)
# any RegExp that matches the allowed input
self.validator = QRegExpValidator(QRegExp("\\d+[\\.]{0,1}[02468]{0,1}"), self)
def validate(self, text, pos):
# this decides if the entered value should be accepted
return self.validator.validate(text, pos)
then instead of using QDoubleSpinBox you would use MySpinBox and leave the input checking to this class.

In your change value method you can do something like this
val = round(self.spinbox1.value(), 1)
if val/2*10 - int(val/2*10):
val = round(val, 1) + .1
It's probably not the best way but it works.