Class to position a window on the screen - python

I am new to Python and this is my fist Python class. I am using PyQt4 framework on Windows 7.
I don't know whether the few lines of code below is correctly written or not. I want to modify it further as:
In the arguments, I want to pass the name of another opened Window (.py) on the screen.
I will be passing the x-coord., y-coord. and the name of the window to position on the screen.
How to modify the code to fulfill these requirements?
Edited Further
class PositionWindow:
def __init__(self, xCoord, yCoord, windowName, parent = None):
self.x = xCoord
self.y = yCoord
self.wName = windowName;
def center(self):
screen = QtGui.QDesktopWidget().screenGeometry()
size = self.geometry()
self.move((screen.width()-size.width())/2, (screen.height()-size.height())/2)

Can't you just use window.setGeometry(x_pos, y_pos, width, height)? A class seem overkill in this case.
See here for documentation.

You can also use
def main():
app = QtGui.QApplication(sys.argv)
gui = Program()
gui.move(380, 170)
gui.show()
app.exec_()
the gui.move() will position your application to the stated coordinates in the parenthesis

Related

Issue about PyQt5

I am trying to create a simple interface like this:
from PyQt5 import QtWidgets,QtGui
class program():
def __init__(self):
self.window = QtWidgets.QWidget()
self.window.setWindowTitle("how many click")
self.text = QtWidgets.QLabel(self.window)
self.text.setText(("not clicked"))
self.text.setGeometry(240,200,300,50)
self.text2 = QtWidgets.QLabel(self.window)
self.picture = QtWidgets.QLabel(self.window)
self.button=QtWidgets.QPushButton(self.window)
self.button.setText("click")
self.button.setFont(QtGui.QFont('',10))
self.button.setGeometry(250,100,200,50)
self.window.setGeometry(600,200,800,600)
self.window.show()
self.count=0
self.button.clicked.connect(self.click)
def click(self):
self.count+= 1
self.text.setText(((f"you clicked {self.count} times")))
self.text.setFont(QtGui.QFont('',10))
if self.count == 5:
self.text2.setText(("You clicked too much"))
self.text2.setGeometry(250, 250, 300, 50)
self.picture.setPixmap(QtGui.QPixmap("C:/Users/Administrator/Desktop/mypic.png"))
self.picture.move(300, 300)
app = QtWidgets.QApplication(sys.argv)
run= program()
sys.exit(app.exec_())
In this code my picture appears when I click 5 times to button but picture becomes very tiny as in pic1. However when I write setPixmap and picture.move codes into init function picture becomes normal size as in pic2.
pic1:
pic2:
The simple solution to your issue is to add the following line after setting the pixmap:
self.picture.adjustSize()
The direct reason is that when when the widget is shown the label has not yet a pixmap, so its geometry is already set to its minimum size (defaults to 100x30). Then, when the pixmap is set, the label doesn't automatically update its size.
The logical reason is that you are using fixed geometries for your widget, and this approach is generaly discouraged for lots of reasons, with the most important being the fact that elements within a window should always adapt their geometries (size and position) to the size of the parent, possibly by occupying all the available space and preventing the elements to become invisible if the window is resized to a smaller size.
To avoid that, you should always use layout managers (in your case, a QVBoxLayout could be enough).
For example:
class program():
def __init__(self):
self.window = QtWidgets.QWidget()
# ...
layout = QtWidgets.QVBoxLayout(self.window)
layout.addWidget(self.text)
layout.addWidget(self.text2)
layout.addWidget(self.picture)
layout.addWidget(self.button)
# it's good practice to always show the window *after* adding all elements
self.window.show()

How to get mouse release coordinates in QGraphicsView

Hi I'm new to Qt and pyside. I'm trying to get the coordinates of mouse in a QGraphicsView instance. I tried to reimplement my mouseReleaseEvent but wondering how would I actually use this reimplemented function.
In MainWindow class:
self.tScn = QtGui.QGraphicsScene()
self.graphicsView_2 = QtGui.QGraphicsView(self.centralwidget, self.tScn)
In MainConsumer class(derived from MainWindow:
def pointSelection(self):
pos = self.tScn.mouseReleaseEvent(QMouseEvent)
print(pos)
def mouseReleaseEvent(self, QMouseEvent):
pos = QMouseEvent.lastScenePos()
print(pos)
return pos
python gives me this warning:
AttributeError: 'PySide.QtGui.QMouseEvent' object has no attribute 'lastScenePos'
I tried couple of different orders and structures but nothing worked and now I am really confused by the relationship between PySide.QtGui.QGraphicsScene.mouseReleaseEvent(event), PySide.QtGui.QGraphicsSceneMouseEvent.lastScenePos(), class PySide.QtGui.QGraphicsSceneMouseEvent([type=None]) and QtCore.QEvent.GraphicsSceneMouseRelease could somebody help me?
Thanks!
Create a class that inherits from QGraphicsScene and has a signal like this
class MyGraphicsScene(QtGui.QGraphicsScene):
signalMousePos = QtCore.pyqtSignal(QtCore.QPointF)
def __init__(self, parent):
super(MyGraphicsScene, self).__init__(parent)
and then override the mouseRelease event in this new class
def mouseReleaseEvent(QGraphicsSceneMouseEvent):
pos = QGrapihcsSceneMouseEvent.lastScenePos()
self.signalMousePos.emit(pos)
Then in your MainConsumer class replace
self.tScn = QtGui.QGraphicsScene()
with
self.tScn = MyQGraphicsScene()
self.tScn.signalMousePos.connect(self.pointSelection)
the pointSelection becomes
def pointSelection(self, pos)
#Whatever you want to do with the position coordinates
and mouseReleaseEvent in MainConsumer is no longer necessary

Qgraphicsview items not being placed where they should be

I recently created a program that will create QgraphicsEllipseItems whenever the mouse is clicked. That part works! However, it's not in the exact place where my cursor is. It seems to be slightly higher than where my mouse cursor is. I do have a QGraphicsRectItem created so maybe the two items are clashing with each other and moving off of one another? How can I get these circles to be placed on top of the rectangle item? Here's the code
class MyView(QtGui.QGraphicsView):
def __init__(self):
QtGui.QGraphicsView.__init__(self)
self.scene = QtGui.QGraphicsScene(self)
self.item = QtGui.QGraphicsRectItem(400, 400, 400, 400)
self.scene.addItem(self.item)
self.setScene(self.scene)
def paintMarkers(self):
self.cursor = QtGui.QCursor()
self.x = self.cursor.pos().x()
self.y = self.cursor.pos().y()
self.circleItem = QtGui.QGraphicsEllipseItem(self.x,self.y,10,10)
self.scene.addItem(self.circleItem)
self.circleItem.setPen(QtGui.QPen(QtCore.Qt.red, 1.5))
self.setScene(self.scene)
class Window(QtGui.QMainWindow):
def __init__(self):
#This initializes the main window or form
super(Window,self).__init__()
self.setGeometry(50,50,1000,1000)
self.setWindowTitle("Pre-Alignment system")
self.view = MyView()
self.setCentralWidget(self.view)
def mousePressEvent(self,QMouseEvent):
self.view.paintMarkers()
Much thanks!
There are two issues with the coordinates you are using to place the QGraphics...Items. The first is that the coordinates from QCursor are global screen coordinates, so you need to use self.mapFromGlobal() to convert them to coordinates relative to the QGraphicsView.
Secondly, you actually want the coordinates relative to the current QGraphicsScene, as this is where you are drawing the item. This is because the scene can be offset from the view (for example panning around a scene that is bigger than a view). To do this, you use self.mapToScene() on the coordinates relative to the QGraphicsView.
I would point out that typically you would draw something on the QGraphicsScene in response to some sort of mouse event in the QGraphicsView, which requires reimplementing things like QGraphicsView.mouseMoveEvent or QGraphicsView.mousePressEvent. These event handlers are passed a QEvent which contains the mouse coordinates relative to the view, and so you don't need to do the global coordinates transformation I mentioned in the first paragraph in these cases.
Update
I've just seen your other question, and now understand some of the issue a bit better. You shouldn't be overriding the mouse event in the main window. Instead override it in the view. For example:
class MyView(QtGui.QGraphicsView):
def __init__(self):
QtGui.QGraphicsView.__init__(self)
self.scene = QtGui.QGraphicsScene(self)
self.item = QtGui.QGraphicsRectItem(400, 400, 400, 400)
self.scene.addItem(self.item)
self.setScene(self.scene)
def paintMarkers(self, event):
# event position is in coordinates relative to the view
# so convert them to scene coordinates
p = self.mapToScene(event.x(), event.y())
self.circleItem = QtGui.QGraphicsEllipseItem(0,0,10,10)
self.circleItem.setPos(p.x()-self.circleItem.boundingRect().width()/2.0,
p.y()-self.circleItem.boundingRect().height()/2.0)
self.scene.addItem(self.circleItem)
self.circleItem.setPen(QtGui.QPen(QtCore.Qt.red, 1.5))
# self.setScene(self.scene) # <-- this line should not be needed here
# Note, I've renamed the second argument `event`. Otherwise you locally override the QMouseEvent class
def mousePressEvent(self, event):
self.paintMarkers(event)
# you may want to preserve the default mouse press behaviour,
# in which case call the following
return QGraphicsView.mousePressEvent(self, event)
Here we have not needed to use QWidget.mapFromGlobal() (what I covered in the first paragraph) because we use a mouse event from the QGraphicsView which returns coordinates relative to that widget only.
Update 2
Note: I've updated how the item is created/placed in the above code based on this answer.

Deleting an item from a scene

I currently am having an issue with a delete button I created that is linked to a QGraphicsScene class. The button is created in the Window class not the MyView class. I am trying to have the user be able to delete marks that were made on a scene but right now it is only deleting the last ellipse item I create and nothing else. The error that pops up usually says that the other objects you are trying to delete are in a different scene. Also the location of the circle object that wants to be deleted is important. So if the user has the cursor over a particular circle that circle item should delete and nothing else. Here's my code:
import sys
from PyQt4 import QtGui, QtCore
#this sets the scene for drawing and the microscope image
class MyView(QtGui.QGraphicsView):
def __init__(self,window):
QtGui.QGraphicsView.__init__(self)
self.window = window
self.scene = QtGui.QGraphicsScene(self)
self.item = QtGui.QGraphicsRectItem(400, 400, 400, 400)
self.scene.addItem(self.item)
self.setScene(self.scene)
def paintMarkers(self,event):
##self.cursor = QtGui.QCursor()
#self.cursor.setShape(2)
p = self.mapToScene(event.x(),event.y())
self.circleItem = QtGui.QGraphicsEllipseItem(p.x(),p.y(),5,5)
self.scene.addItem(self.circleItem)
self.circleItem.setPen(QtGui.QPen(QtCore.Qt.red, 1.5))
#self.setScene(self.scene)
def deleteMarkers(self):
self.scene.removeItem(self.circleItem)
#print "Hello world"
#def mousePressEvent(self,QMouseEvent):
#self.paintMarkers()
def mousePressEvent(self,event):
if self.window.btnPaintDot.isChecked():
self.paintMarkers(event)
if self.window.btnDeleteMarks.isChecked():
self.deleteMarkers()
return QtGui.QGraphicsView.mousePressEvent(self,event)
class Window(QtGui.QMainWindow):
def __init__(self):
#This initializes the main window or form
super(Window,self).__init__()
self.setGeometry(50,50,1000,1000)
self.setWindowTitle("Pre-Alignment system")
self.view = MyView()
self.setCentralWidget(self.view)
#makes deletemarks button checked when pressed
def paintDeleteMarks(self):
if self.btnDeleteMarks.isChecked():
self.btnPaintDot.setChecked(False)
self.btnPaintPolygon.setChecked(False)
self.btnPaintPolygon.setChecked(False)
self.btnDeleteMarks.setChecked(True)
else:
self.btnDeleteMarks.setChecked(False)
Much thanks please ask questions if my explanation needs more...well explaining.
If you carefully read over your code, you will see that you are deleting the item stored in self.circleItem. The item stored in that variable is always only the last one created (you overwrite the variable each time you create a new item).
You need to modify your code so that it finds items based on the current x-y coordinate of the mouse event. Use QGraphicsScene.itemAt() to find the item at a particular x-y coordinate (remember to correctly transform the coordinates relative to the scene before looking up the item at that location).
Here is the code that fixed the issue thanks to three_pineapples!
import sys
from PyQt4 import QtGui, QtCore
#this sets the scene for drawing and the microscope image
class MyView(QtGui.QGraphicsView):
def __init__(self,window):
QtGui.QGraphicsView.__init__(self)
self.window = window
self.scene = QtGui.QGraphicsScene(self)
self.item = QtGui.QGraphicsRectItem(400, 400, 400, 400)
self.scene.addItem(self.item)
self.setScene(self.scene)
def paintMarkers(self,event):
##self.cursor = QtGui.QCursor()
#self.cursor.setShape(2)
p = self.mapToScene(event.x(),event.y())
if (p.x() > 400 and p.x() < 800) and (p.y() > 400 and p.y() < 800):
self.circleItem = QtGui.QGraphicsEllipseItem(p.x(),p.y(),5,5)
self.scene.addItem(self.circleItem)
self.circleItem.setPen(QtGui.QPen(QtCore.Qt.red, 1.5))
#self.setScene(self.scene)
def deleteMarkers(self,event):
p = self.mapToScene(event.x(),event.y())
if self.scene.itemAt(p.x(),p.y()) != self.item:
self.scene.removeItem(self.scene.itemAt(p.x(),p.y()))
#print "Hello world"
#def mousePressEvent(self,QMouseEvent):
#self.paintMarkers()
def mousePressEvent(self,event):
if self.window.btnPaintDot.isChecked():
self.paintMarkers(event)
if self.window.btnDeleteMarks.isChecked():
self.deleteMarkers(event)
return QtGui.QGraphicsView.mousePressEvent(self,event)

Where should i place mainloop?

I have a program written in IDLE3.3 and tkinter where I don't know where to place the mainloop(). The program creates a systray icon that creates a little note if you click on "new note" in the context menu. If there is the line "self.root.mainloop()" at the end of Note.init(), the note is shown, but only one note. if I create a second one, the first note is dead and nothing further happens.
But if I don't call the mainloop() in the init-method, i see that there a several notes created because it is printed in the shell.
So the question is, where should I place the mainloop so that every newly created notw is shown and works? Sorry for that possibly stupid question but I can't figure it out.
from tkinter import *
import sys
from PyQt4.QtGui import *
import threading
class Note():
yellow=["#e7e37c","#d9d574"]
def __init__(self,noteset=None, properties=None):
self.root=Tk()
self.noteset=noteset
self.properties=properties
self.screen_width = self.root.winfo_screenwidth()
self.screen_height = self.root.winfo_screenheight()
print("No initial properties to load => creating new note")
self.notecolor=self.yellow[0]
self.gripcolor=self.yellow[1]
self.root.overrideredirect(1)
self.text=""
self.font="arial"
self.fontsize=10
self.sizeX=250
self.sizeY=200
self.posX=int(self.screen_width/2 - self.sizeX/2)
self.posY=int(self.screen_height/2 - self.sizeY/2)
self.root.wm_geometry("%sx%s+%s+%s" %(self.sizeX, self.sizeY, self.posX, self.posY) )
self.root.wm_attributes("-topmost",1)
self.GUI()
self.bindings()
self.root.mainloop()
def bindings(self):
self.frmGRIP.bind("<ButtonPress-1>", self.StartMove)
self.frmGRIP.bind("<ButtonRelease-1>", self.StopMove)
self.frmGRIP.bind("<B1-Motion>", self.OnMotion)
def StartMove(self, event):
self.startx = event.x
self.starty = event.y
def OnMotion(self, event):
mousex,mousey=self.root.winfo_pointerxy()
self.root.geometry("+%s+%s" % (mousex-self.startx, mousey-self.starty))
def StopMove(self, event):
self.posX = self.root.winfo_x()
self.posY = self.root.winfo_y()
def GUI(self):
self.frmTOP=Frame(master=self.root,height=15)
self.frmBOTTOM=Frame(master=self.root,width=300,height=300)
self.frmGRIP=Frame(self.frmTOP,bg=self.gripcolor,height=15)
self.frmRESIZE=Frame(self.frmBOTTOM,width=300,height=10)
self.frmTEXT=Frame(self.frmBOTTOM,bg=self.notecolor,width=300,height=300)
self.frmRESIZE_empty=Frame(self.frmRESIZE,bg=self.notecolor,height=10)
self.frmRESIZE_grip=Frame(self.frmRESIZE,bg=self.gripcolor,width=10,height=10)
self.frmTOP.pack(fill=X,expand=NO)
self.frmBOTTOM.pack(side=BOTTOM,fill=BOTH,expand=YES)
self.frmGRIP.pack(side=LEFT,fill=X,expand=YES)
self.frmRESIZE.pack(side=BOTTOM,fill=X)
self.frmTEXT.pack(side=BOTTOM,fill=BOTH,expand=YES)
self.frmRESIZE_empty.pack(side=LEFT,fill=X,expand=YES)
self.frmRESIZE_grip.pack(side=LEFT,expand=NO)
self.T=Text(self.frmTEXT,
height=6,width=30,
bd=0,wrap=WORD,pady=3,padx=5,
bg=self.notecolor,undo=1,
font=(self.font,self.fontsize)
)
self.T.insert(END,self.text)
self.T.pack(fill=BOTH,expand=YES)
class Noteset():
def __init__(self):
self.notes = []
def newNote(self):
note=Note(noteset=self)
self.notes.append(note)
print(self.notes)
return note
class Main():
def __init__(self):
self.N=Noteset()
app = QApplication(sys.argv)
trayIcon = QSystemTrayIcon(QIcon("J:\\python\\SimpleNotes.ico"), app)
menu = QMenu()
ActionNewNote = menu.addAction("new Note")
ActionNewNote.triggered.connect(self.newNote)
trayIcon.setContextMenu(menu)
trayIcon.show()
app.exec()
def newNote(self):
self.N.newNote()
Main()
You cannot successfully use Qt and Tkinter together. Also, if you remove Qt from the above you have the additional problem that you should not create more than once instance of Tk.
To answer your specific question, mainloop is normally the very last line of code that you execute. Since it is an infinite loop, any code after you call mainloop won't execute until the main window is destroyed.
The normal structure for a Tkinter application goes something like this:
import Tkinter as tk
class MyApp(...):
def __init__(self, root, ...):
...
...
root = tk.Tk()
myApp(root)
root.mainloop()
Its not a good idea to mix gui frameworks as each of the mainloops block each other, your better off to code the whole thing in one or the other.

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