I'm using a custom container where I need to reorder widgets but there are no methods to do it. So I tried to remove all the widgets and add them again in order.
The problem is that this is not working well, I can't see the widgets after adding them again, I guess what's happening is that when I remove the widgets they become unrealized.
Is there any way of removing a widget an reuse it later?
The pygtk docs provide a bit of insight.
Note that the container will own a
reference to widget, and that this may
be the last reference held; so
removing a widget from its container
can cause that widget to be destroyed.
If you want to use widget again, you
should add a reference to it.
EDITS
I just quickly modified pygtk's Hello World to add/remove/reorder widgets in a container. This works because the button1 is a member variable of the class, it never goes out of scope.
#!/usr/bin/env python
# example helloworld2.py
import pygtk
pygtk.require('2.0')
import gtk
class HelloWorld2:
# Our new improved callback. The data passed to this method
# is printed to stdout.
def callback_remove(self, widget, data):
self.box1.remove(self.button1);
def callback_add(self, widget, data):
self.box1.pack_start(self.button1, True, True, 0)
# another callback
def delete_event(self, widget, event, data=None):
gtk.main_quit()
return False
def __init__(self):
# Create a new window
self.window = gtk.Window(gtk.WINDOW_TOPLEVEL)
# This is a new call, which just sets the title of our
# new window to "Hello Buttons!"
self.window.set_title("Hello Buttons!")
# Here we just set a handler for delete_event that immediately
# exits GTK.
self.window.connect("delete_event", self.delete_event)
# Sets the border width of the window.
self.window.set_border_width(10)
# We create a box to pack widgets into. This is described in detail
# in the "packing" section. The box is not really visible, it
# is just used as a tool to arrange widgets.
self.box1 = gtk.HBox(False, 0)
# Put the box into the main window.
self.window.add(self.box1)
# Creates a new button with the label "Button 1".
self.button1 = gtk.Button("Button 1")
# Now when the button is clicked, we call the "callback" method
# with a pointer to "button 1" as its argument
self.button1.connect("clicked", self.callback_remove, "button 1")
# Instead of add(), we pack this button into the invisible
# box, which has been packed into the window.
self.box1.pack_start(self.button1, True, True, 0)
# Always remember this step, this tells GTK that our preparation for
# this button is complete, and it can now be displayed.
self.button1.show()
# Do these same steps again to create a second button
self.button2 = gtk.Button("Button 2")
# Call the same callback method with a different argument,
# passing a pointer to "button 2" instead.
self.button2.connect("clicked", self.callback_add, "button 2")
self.box1.pack_start(self.button2, True, True, 0)
# The order in which we show the buttons is not really important, but I
# recommend showing the window last, so it all pops up at once.
self.button2.show()
self.box1.show()
self.window.show()
def main():
gtk.main()
if __name__ == "__main__":
hello = HelloWorld2()
main()
Just set the widget's visibility property to False, and set it to True later, with the set_visible method.
no he need only widgrt.its objects not need.then visible must not used.it will only hide graphicaly.but memmory still not released
remove function is the answer
Related
I have an Actor BP, inside this BP I have a UWidgetComponent with a Widget Class already selected in the Details, and that Widget Class has a TextBlock. Now, inside this BP I also have a C++ USceneComponent, this component is in charge of showing a random text, in the TextBlock mentioned above, each time the user presses a button.
This is in my USceneComponent's header file (.h)
class UWidgetComponent* QuestionWidget;
class UQuestionProjectionText* QuestionText;
class UTextBlock* QuestionTextBlock;
Then in the ".cpp" file, in the constructor
QuestionWidget = CreateDefaultSubobject<UWidgetComponent>(TEXT("CodeQuestionWidget"));
QuestionTextBlock = CreateDefaultSubobject<UTextBlock>(TEXT("CodeTextBlock"));
Then in the BeginPlay()
//Gets the WidgetComponent from the BP
QuestionWidget = Cast<UWidgetComponent>(GetOwner()->GetComponentByClass(UWidgetComponent::StaticClass()));
if (QuestionWidget)
{
QuestionWidget->InitWidget();
//Gets an instance of the UMyUserWidget class, from the UWidgetComponent in the BP
QuestionText = Cast<UMyUserWidget>(QuestionWidget->GetUserWidgetObject());
this->QuestionTextBlock = QuestionText->QuestionTextBlock;
//Sets the text to an empty String
QuestionTextBlock->SetText(FText::FromString(""));
}
else
{
UE_LOG(LogTemp, Error, TEXT("QuestionWidget was not found"));
return;
}
Then in the TickComponent(), when the user presses the button, I use a something that looks like this
QuestionTextBlock->SetText(FText::FromString(QuestionStringsArray[9]));
The problem is that when I press the button, the text does not change in the Widget, but if I print the text that I'm passing, it does print the string, so I'm not passing an empty value to the "SetText()".
Another weird thing, is that the line in the BeginPlay that sets the text, that one works, I have changed it to a random string, instead of an empty one, and it does display it.
I don't know if when I do the "QuestionWidget->InitWidget();" I'm creating a new one separate from the one in the BP, or if I'm just missing something. If I eliminate the "QuestionWidget->InitWidget()" the widget gets initialized on time sometimes, and sometimes it doesn't.
I have some error handling in my code, but eliminated it here so that it didn't look too messy. But also, none of the Errors popup, everything goes on smoothly, only that the Widget doesn't show the updated Text.
I am developing a QGIS plugin in python and hit a roadblock when displaying my GUI. I am using the plugin builder framework to develop my plugin and I have trouble displaying a checkable combo box in a scrollArea in my GUI. The code with core functionality is as follows.
def run(self):
# Only create GUI ONCE in callback, so that it will only load when the plugin is started
if self.first_start == True:
self.first_start = False
# Sets up the pyqt user interface
self.dlg = EarthingToolDialog()
# Fetching the active layer in the QGIS project
layer = self.iface.activeLayer()
checkable_combo = CheckableComboBox()
# Going through each field of the layer
# and adding field names as items to the
# combo box
for j,field in enumerate(layer.fields()):
checkable_combo.addItem(str(field.name()))
# Setting the checked state to True by default
checkable_combo.setItemChecked(j, True)
# putting the check box inside the scroll area of the GUI
self.dlg.scrollArea.setWidget(checkable_combo)
self.dlg.scrollArea.setMinimumSize(QSize(700,400))
# show the dialog
self.dlg.show()
# Run the dialog event loop
self.dlg.exec_()
class EarthingToolDialog(QtWidgets.QDialog, FORM_CLASS):
def __init__(self, parent=None):
"""Constructor."""
super(EarthingToolDialog, self).__init__(parent)
self.setupUi(self)
class CheckableComboBox(QComboBox):
def __init__(self):
super().__init__()
self._changed = False
self.view().pressed.connect(self.handleItemPressed)
def setItemChecked(self, index, checked=False):
print('checked')
item = self.model().item(index, self.modelColumn()) # QStandardItem object
print(type(item))
if checked:
item.setCheckState(Qt.CheckState.Checked)
else:
item.setCheckState(Qt.CheckState.Unchecked)
def handleItemPressed(self, index):
print('pressed')
item = self.model().itemFromIndex(index)
if item.checkState() == Qt.Checked:
item.setCheckState(Qt.Unchecked)
else:
item.setCheckState(Qt.Checked)
self._changed = True
print('set ' + str(item.checkState()))
def hidePopup(self):
print('hide')
if not self._changed:
super().hidePopup()
self._changed = False
def itemChecked(self, index):
print('read')
item = self.model().item(index, self.modelColumn())
return item.checkState() == Qt.Checked
In summary, the run function is the main function called by the plugin when it is loaded. self.dlg is the instance of the actual pyqt python user interface. This is rendered with the help of the EarthingToolDialog class. The checkable combo box and it's functionalities are self contained in the CheckableComboBox class.
The run function executes without any error when the plugin is loaded but the checkboxes are not visible in the combobox. Just a normal combo box with a list of items (just the standard dropdown combo box) is seen on the GUI's scroll area and not the desired checkable combo box. The CheckableComboBox class was taken from https://morioh.com/p/d1e70112347c and it runs perfectly well in the demo code shown there.
I understand that this is a very specific question and it would be great if someone could figure out what the problem might be. Thanks in advance!
Within the run function, this piece of codes didn't work for me:
self.dlg.scrollArea.setWidget(checkable_combo)
self.dlg.scrollArea.setMinimumSize(QSize(700,400))
So instead, I use:
layout = QVBoxLayout()
layout.addWidget(checkable_combo)
self.dlg.setLayout(layout)
I didn't use directly this class (It was generated automatically since I use Plugin Builder, so in here I commented it):
class EarthingToolDialog(QtWidgets.QDialog, FORM_CLASS):
def __init__(self, parent=None):
"""Constructor."""
super(EarthingToolDialog, self).__init__(parent)
self.setupUi(self)
Now, in order to display checkable combo box, CheckableComboBox constructor is changed as :
def __init__(self):
super().__init__()
self._changed = False
self.view().pressed.connect(self.handleItemPressed)
delegate = QtWidgets.QStyledItemDelegate(self.view())
self.view().setItemDelegate(delegate)
The last two lines are from the answer listed here.
Codes display checkable combo box list with all items checked by default.
In the onChange of React-Bootstrap-Typeahead, I need to manually set a custom display value. My first thought was to use a ref and do something similar to the .clear() in this example.
But although .clear() works, inputNode.value = 'abc' does not work, and I'm left with the old selected value from the menu.
onChange={option => {
typeaheadRef.current.blur(); // This works
typeaheadRef.current.inputNode.value = 'abc'; // This does not work (old value is retained)
}}
I also tried directly accessing the DOM input element, whose ID I know, and doing
var inputElement = document.querySelector('input[id=myTypeahead]');
inputElement.value = 'abc';
But that didn't work either. For a brief second, right after my changed value = , I do see the new display label, but then it's quickly lost. I think the component saves or retains the menu-selected value.
Note: I cannot use selected, I use defaultSelected. I have some Formik-related behavior that I've introduced, and it didn't work with selected, so I'm stuck with defaultSelected.
The only workaround I found is to re-render the Typeahead component (hide and re-show, from a blank state) with a new defaultSelected="abc" which is a one-time Mount-time value specification for the control.
I couldn't get selected=.. to work, I have a wrapper around the component which makes it fit into Formik with custom onChange and onInputChange and selected wasn't working with that.
So the simple workaround that works is, if the visibility of the Typeahead depends on some condition (otherwise it won't be rendered), use that to momentarily hide and re-show the component (a brand new repaint) with a new defaultSelected, e.g.
/* Conditions controlling the visibility of the Typeahead */
!isEmptyObject(values) &&
(values.approverId === null || (values.approverId !== null && detailedApproverUserInfo)
)
&&
<AsyncTypehead defaultSelected={{...whatever is needed to build the string, or the literal string itself...}}
..
// Given the above visibility condition, we'll hide/re-show the component
// The below will first hide the control in React's renders
setFieldValue("approver", someId);
setDetailedUserInfo(null);
// The below will re-show the control in React's renders, after a small delay (a fetch)
setDetailedUserInfo(fetchDetailedUserInfo());
I add a button to HBox, with expand equal to False, but I want the button to have more spacing between its label and border. I assume it is "inner-border" property, but it is read-only. How can I set it to e.g. 4px?
gtk.Label is a subclass of gtk.Misc which has the method set_padding. If you get the label out of the gtk.Button then you can just call set_padding on it.
You could do something like:
label = gtk.Label("Hello World")
button = gtk.Button()
/* Add 10 pixels border around the label */
label.set_padding(10, 10)
/* Add the label to the button */
button.add(label)
/* Show the label as the button will assume it is already shown */
label.show()
Wrong answer:
What you're looking for is called "padding". When you add your button to the container, for example by calling gtk.Box.pack_start, just set the padding parameter to a positive integer.
Update:
Seems I misread the question. In that case, my guess is that you're supposed to use gtk_widget_modify_style, as inner-border is a style property. You'll first get the style modifier you need by calling gtk_widget_get_modifier_style. You'll then be able to modify the style only for that button using the ressource styles matching rules.
you can use "inner-border" style property of gtk button.
here, small code snippets
In gtkrc file:
style "button_style"
{
GtkButton::inner-border = {10,10,10,10}
}
class "GtkButton" style "button_style"
In .py file:
gtk.rc_parse(rc_file_path + rc_file)
[Edit]
In gtkrc file:
style "button_style"
{
GtkButton::inner-border = {10,10,10,10}
}
widget "*.StyleButton" style "button_style" # apply style for specific name of widget
In .py file:
gtk.rc_parse(rc_file_path + rc_file)
#set name of button
self.style_button.set_name('StyleButton')
hope, it would be helpful.
I sometimes just add spaces in the label !
gtk.Button(" Label ")
to get some spacing.
Hope this could help you.
Coming from this question, I have a wxComboCtrl with a custom popup made of a panel with a bunch of radiobuttons.. My problem is that when I open the popup the combo doesn't get keystrokes, because the events get handled by the panel itself.. I'd like to redirect those KeyEvents to the textctrl of the combo, but I can't find a way to get it to work :/
Am I going the wrong way? Should I manually handle the textctrl value as the user presses keys? I think that would be a bit cumbersome though.. Since supposedly the textctrl already knows how to handle those events..
Here's my testcase (wxPython 2.8 on Linux), the "on_key" method should be the culprit:
import wx
import wx.combo
class CustomPopup(wx.combo.ComboPopup):
def Create(self, parent):
# Create the popup with a bunch of radiobuttons
self.panel = wx.Panel(parent)
sizer = wx.GridSizer(cols=2)
for x in range(10):
r = wx.RadioButton(self.panel, label="Element "+str(x))
r.Bind(wx.EVT_RADIOBUTTON, self.on_selection)
sizer.Add(r)
self.panel.SetSizer(sizer)
# Handle keyevents
self.panel.Bind(wx.EVT_KEY_UP, self.on_key)
def GetControl(self):
return self.panel
def GetAdjustedSize(self, minWidth, prefHeight, maxHeight):
return wx.Size(200, 150)
def on_key(self, evt):
if evt.GetEventObject() is self.panel:
# Trying to redirect the key event to the combo.. But this always returns false :(
print self.GetCombo().GetTextCtrl().GetEventHandler().ProcessEvent(evt)
evt.Skip()
def on_selection(self, evt):
self.Dismiss()
wx.MessageBox("Selection made")
class CustomFrame(wx.Frame):
def __init__(self):
# Toolbar-shaped frame with a ComboCtrl
wx.Frame.__init__(self, None, -1, "Test", size=(800,50))
combo = wx.combo.ComboCtrl(self)
popup = CustomPopup()
combo.SetPopupControl(popup)
sizer = wx.BoxSizer(wx.VERTICAL)
sizer.Add(combo, 0)
self.SetSizer(sizer)
self.Layout()
if __name__ == '__main__':
app = wx.PySimpleApp()
CustomFrame().Show()
app.MainLoop()
Edit:
I found these (unresolved) discussions on the same topic..
"ComboCtrl loses keyboard focus when ComboPopup is shown "
"issue using wx.ComboCtrl"
I had the same problem with a custom ComboPopup control using a panel as the basis of the control.
EmulateKeypress just entered a never-ending loop. I found binding the panel to the EVT_KEY_DOWN and EVT_CHAR to the overridden OnComboKeyEvent function and skipping the event down the event handling chain was all that was required to enable entering text into the textbox of the ComboCtrl with the popup open. I think this makes sense. As the Popup isn't strictly a control its events won't belong anywhere until bound into the the wx.app event loop through the Bind() method.
I've included the overridden OnComboKeyEvent function below so that anyone else can explore this problem.
def create(self, *args, **kwds):
...
self.panel.Bind(wx.EVT_CHAR, self.OnComboKeyEvent)
self.panel.Bind(wx.EVT_KEY_DOWN, self.OnComboKeyEvent)
...
def OnComboKeyEvent(self, evt):
evt_dict = {wx.EVT_TEXT.typeId: "TextEvent",
wx.EVT_CHAR.typeId:"CharEvent",
wx.EVT_CHAR_HOOK.typeId:"CharHookEvent",
wx.EVT_KEY_UP.typeId:"KeyUpEvent",
wx.EVT_KEY_DOWN.typeId:"KeyDownEvent"}
if evt.GetEventType() in evt_dict:
thelogger.debug("oncombokeyevet:%s" % evt_dict[evt.GetEventType()])
super().OnComboKeyEvent(evt)
evt.Skip()
I've got an answer from Robin Dunn himself on wxpython-users:
Sending low-level events to native
widgets like this does not work the
way that most people expect it to.
You are expecting this to result in
the character being added to the text
ctrl,but it can't do that because all
that ProcessEvent does is send the
wx.Event to any bound event handlers
and then it stops. It does not go to
the next step and convert that event
to the equivalent native message and
send it on to the native widget. See
the "Simulating keyboard events"
thread.
It doesn't work especially well on
non-Windows platforms, but you could
try calling EmulateKeypress instead.