I'm trying to write a script for an application developed with Qt, using javascript for the business logic and a .ui file for the GUI, but I'm facing two problems.
In the ui I declared a QComboBox, to which I successfully connect javascript functions to handle
signals such as editTextChanged, etc. I was wondering I cannot populate the combobox from within
javascript code, because the addItem function is not exposed to script-side code.
combobox.editTextChanged[action](ComboBoxChanged); // OK (action is "connect" or "disconnect")
combobox.addItem("element 1"); // Error!
Is there any (other) way to do this?
I need to show a set of items (strings) in a table-like component. I tried using a QTableView and
QTableWidget but I cannot insert or get items. For example, from javascript I cannot access the
setModel function of a QTableView (if at least I could create a QAbstractItemModel from
script...), neither I can access the item(row,col) function of a QTableWidget class, to set an
item's text. Is there any way to show a table of strings to the user, let edit them and retrieve
the modified contents?
Thanks in advance.
Antonio
Because the addItem() function isn't a slot, you'll need an intermediate public slot to handle the transaction. It'll be the same with the other functions you are trying to get at as well.
Related
There is a dictionary taken from JSON file, that is represented by QTreeView QStandardItemModel.
A user can reorganize QTreeView(add, delete, drag-n-drop) and rename items.
The goal is: call function that reads changed QTreeView, makes the dictionary and writes it to initial JSON file.
I can do it by pressing a QPushButton after changes occurred or by binding that function to every change e.g. call function when an item is deleted, call function when an item is added, call a function when an item is renamed and so on.
Is there any way to call a function if any of changes occur? Is there such a signal that corresponds to all of the mentioned changes?
The rowsMoved and itemChanged signals do what you think they do. See http://doc.qt.io/qt-4.8/qstandarditemmodel.html
As #vahancho suggests in the comments, you should connect to the layoutChanged signal. All models should emit this immedaitely after making any changes which could affect the view. So this will include sorting and filtering, as well as re-ordering, editing, deleting, etc.
The dataChanged signal is similar, but only really useful if you want to monitor specific items.
In my program I use QTableView and QAbstractTableModel that are connected. Model doesn't contain data. When view needs data to show it calls QAbstractTableModel::data and model uses another object to get data and return. At some point data in that object is going changed. Model doesn't know what has changed so dataChanged is not called.
I need that only visible part of data (that is shown in view) goes updated. It should get new data from model. I am trying to achieve that by calling update() or repaint() functions of view but it doesn't help. I am thinking that it should call paintEvent of tableview but it is not called.
How is it possible to make view update visible part of data? I don't want to update whole data that is huge.
Your wishes brokes Qt MVC logic. But if you need workaround - you may do next call to update visible area: emit dataChanged( QModelIndex(), QModelIndex() );
I use Qt Designer to build my UI layout. On the layout, I have a combobox named cb_fac_cd. In my code I have a function that will automatically build a combobox based on the list I'm attempting to build. I have a lot of these lists defined in the database and this function spits out a QComboBox.
Unfortunately, until now I've only used this function to add cellWidgets to QTableWidgets. It works perfectly there. Now I want to populate this preexisting combobox.
It seems that a simple
self.ui.cb_fac_cd = makeComboBox('FACILITIES') doesn't work. I can see that the function returns the QComboBox as usual, but the cb_fac_cd combobox remains unpopulated.
How can I copy or assign the returned combobox to the one build in Qt Designer?
I am using PyQt, but that shouldn't make any difference.
As far as I know, you cannot replace objects which are part of the .h files generated by Qt's UIC mechanism (though I cannot confirm that 100% right now).
What I usually do in such cases is to have an empty layout in the ui file and then do the following:
(Note that I'm using Qt/C++ syntax as I don't know the pyqt syntax but I think you will get the idea)
QComboBox* pNewComboBox = makeComboBox( "FACILITIES" );
ui.pComboBoxLayout->addWidget( pComboBox );
Additionally, if possible for your program, consider using an enumeration rather than a string for your makeComboBox function. This is usually faster and safer.
It sounds like you should either
Change makeComboBox to populateComboBox(QComboBox *p) and pass it the combobox in your layout to fill, or
Create and add the QComboBox to your layout dynamically and remove it from your .ui
You can change the model from you Ui to the one you get from the other combobox:
tempCombo = makeComboBox( "FACILITIES" )
self.ui.cb_fac_cd.setModel(tempCombo.model())
But for that part:
I have a lot of these lists defined in the database and this function
spits out a QComboBox. Unfortunately, until now I've only used this function to add
cellWidgets to QTableWidgets.
If the data comes from a database, you might want to look at QSqlRelationalTableModel to avoid doing that manually.
How can I autocommit data from QTableWidget, that is in editing state, when I fire some command?
Assume, that there is some grid and data in it (editable thorough delegate that fires QComboBox editor). So, one starting to select option in combo, but do not finish editing, then hit some button, that executes action, that uses data from that combo, but new choise is not committed yet :\
How can I programmatically finish editing in table?
I mean some not strict 'loop all items and finish editing' way, that I consider as bad and ugly.
OOPS: worked too much, so, haven't realised, that there could be only one pending editor at time. Question is still here.
There is a protected slot named "commitData" in the tableWidget. You can inherit from tableWidget, then add your own public method (or slot) and send a signal (or simply call commitData method) from there.
There is one problem. You'll need to provide the editor object, but tableWidget gives you no way to get the pointer you need.
If you're using your own createEditor method, you can save the pointer to the editor somewhere, where your method can get it. It's a hack, but it's the only way i know.
The current editor does not seem to be accessible from outside of the view, but its content is committed when the current model index changes. So a simple way to force a commit seems to be to call
table->setCurrentIndex (QModelIndex ())
plus restoring your previous current index afterwards if the widget is not discarded yet.
This is quite an old question but it still came up quite high on Google so just in case anyone else needs the answer QTableView has a protected method
void currentChanged(const QModelIndex ¤t, const QModelIndex &previous)
which causes the data to be commited and QTableWidget is built on QTableView so that should still work. I found this info on the Qt Forum.
I am using QT4 and dynamically adding entries to a QMenu. Is it possible to sort the entries in the QMenu without deleting it and creating a new one?
I originally thought there was a function to insert at a specific location so I could sort on insert, but I have not been able to locate it.
Once added, I don't think you can reorder. While you are creating though you could use the QWidget::insertAction method to place it exactly where you want it.
void QWidget::insertAction ( QAction * before, QAction * action )
Otherwise you could use QWidget::addActions. Create your list of Actions and sort it before adding to the QMenu.
void QWidget::addActions ( QList<QAction *> actions )
In one of my codes, I save the QActions into a separate List and generate the menus and submenus on demand. In theory, I can add "weight" to the items and have them re-ordered, but I have not implemented this yet.
Project page is available here: http://code.google.com/p/qtedit4/wiki/qmdilib
Please note that the actions of QWidget (and QMenu) are stored as a QList which can be "read", using QWidget::actions() . Remember that the list is copied, so you can modify the actions but not the list itself. (I hope I am not mistaking...)