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The QComboBox widget is a combined button and popup list. More...
#include <QComboBox>
Inherits QWidget.
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The QComboBox widget is a combined button and popup list.
A QComboBox provides a means of presenting a list of options to the user in a way that takes up the minimum amount of screen space.
A combobox is a selection widget that displays the current item, and can pop up a list of selectable items. A combobox may be editable, allowing the user to modify each item in the list.
Comboboxes can contain pixmaps as well as strings; the insertItem() and changeItem() functions are suitably overloaded. For editable comboboxes, the function clearEdit() is provided, to clear the displayed string without changing the combobox's contents.
A combobox emits two signals, activated() and highlighted(), when a new item has been activated (selected) or highlighted (made current). Both signals exist in two versions, one with a QString argument and one with an int argument. If the user highlights or activates a pixmap, only the int signals are emitted. Whenever the text of an editable combobox is changed the editTextChanged() signal is emitted.
When the user enters a new string in an editable combobox, the widget may or may not insert it, and it can insert it in several locations. The default policy is is AtBottom but you can change this using setInsertPolicy().
It is possible to constrain the input to an editable combobox using QValidator; see setValidator(). By default, any input is accepted.
A combobox can be populated using the insert functions, insertStringList() and insertItem() for example. Items can be changed with changeItem(). An item can be removed with removeItem() and all items can be removed with clear(). The text of the current item is returned by currentText(), and the text of a numbered item is returned with text(). The current item can be set with setCurrentIndex(). The number of items in the combobox is returned by count(); the maximum number of items can be set with setMaxCount(). You can allow editing using setEditable(). For editable comboboxes you can set auto-completion using setAutoCompletion() and whether or not the user can add duplicates is set with setDuplicatesEnabled().
See also QLineEdit, QSpinBox, QRadioButton, QButtonGroup, and GUI Design Handbook: Combo Box, Drop-Down List Box.
This enum specifies what the QComboBox should do when a new string is entered by the user.
| Constant | Value | Description |
|---|---|---|
| QComboBox::NoInsert | 0 | The string will not be inserted into the combobox. |
| QComboBox::InsertAtTop | 1 | The string will be inserted as the first item in the combobox. |
| QComboBox::InsertAtCurrent | 2 | The current item will be replaced by the string. |
| QComboBox::InsertAtBottom | 3 | The string will be inserted after the last item in the combobox. |
| QComboBox::InsertAfterCurrent | 4 | The string is inserted after the current item in the combobox. |
| QComboBox::InsertBeforeCurrent | 5 | The string is inserted before the current item in the combobox. |
This enum specifies how the size of the QComboBox should adjust when new content is added or content changes.
| Constant | Value | Description |
|---|---|---|
| QComboBox::AdjustToContents | 0 | The combobox will always adjust to the contens |
| QComboBox::AdjustToContentsOnFirstShow | 1 | The combobox will adjust to its contents the first time it is show. |
| QComboBox::AdjustToMinimumContentsLength | 2 | The combobox only adjusts to the minimumContentsLength |
This property holds whether the combobox provides auto-completion for editable items.
This property was introduced in Qt 4.1.
Access functions:
See also editable.
This property holds the case-sensitive property used in auto-completion.
Access functions:
See also autoCompletion.
This property holds the number of items in the combobox.
Access functions:
This property holds the index of the current item in the combobox. The index can change when inserting or removing items. Returns -1 if no current item is set or the combobox is empty.
Access functions:
This property holds the text of the current item.
Access functions:
This property holds whether the user can enter duplicate items into the combobox.
Note that it is always possible to programatically insert duplicate items into the combobox.
Access functions:
This property holds whether the combobox can be edited by the user.
Access functions:
This property holds whether the combo box draws itself with a frame.
If enabled (the default) the combo box draws itself inside a frame, otherwise the combo box draws itself without any frame.
Access functions:
This property holds the size of the icons shown in the combobox.
Unless explicitly set this returns the default value of the current style.
Access functions:
This property holds the policy used to determine where user-inserted items should appear in the combobox.
The default value is AtBottom, indicating that new items will appear at the bottom of the list of items.
Access functions:
See also InsertPolicy.
This property holds the maximum number of items allowed in the combobox.
Note: If you set the maximum number to be less then the current amount of items in the combobox, the extra items will be truncated. This also applies if you have set an external model on the combobox.
Access functions:
This property holds the maximum allowed size on screen of the combobox.
Access functions:
This property holds the value describing the minimum number of characters that will fit into the combobox.
This value is ignored if AdjustToMinimumContentsLength is not set. The default value is 0.
Access functions:
See also sizeAdjustPolicy.
This property holds the column in the model that is visible.
Access functions:
This property holds the policy describing how the size of the combobox changes when the content changes.
The default value is AdjustToContentsOnFirstShow.
Access functions:
See also SizeAdjustPolicy.
Constructs a combobox with the given parent, using the default model QStandardItemModel.
Destroys the combobox.
This signal is sent when an item in the combobox is activated by the user. The item's index is given.
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
This signal is sent when an item in the combobox is activated by the user. The item's text is given.
Adds an item to the combobox with the given text, and containing the specified userData. The item is appended to the list of existing items.
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
Adds an item to the combobox with the given icon and text, and containing the specified userData. The item is appended to the list of existing items.
Adds each of the strings in the given texts to the combobox. Each item is appended to the list of existing items in turn.
Clears the combobox, removing all items.
Note: If you have set an external model on the combobox this model will still be cleared when calling this function.
Clears the contents of the line edit used for editing in the combobox.
This signal is sent whenever the currentIndex in the combobox changes either through user interaction or programmatically. The item's index is given or -1 if the combobox becomes empty or the currentIndex was reset.
This function was introduced in Qt 4.1.
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
This signal is sent whenever the currentIndex in the combobox changes either through user interaction or programmatically. The item's text is given.
This function was introduced in Qt 4.1.
This signal is emitted when the text in the combobox's line edit widget is changed. The new text is specified by text.
Returns the index of the item containing the given data for the given role; otherwise returns -1.
The flags specify how the items in the combobox are searched.
Returns the index of the item containing the given text; otherwise returns -1.
The flags specify how the items in the combobox are searched.
Hides the list of items in the combobox if it is currently visible; otherwise this function does nothing.
This signal is sent when an item in the combobox is highlighted by the user. The item's index is given.
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
This signal is sent when an item in the combobox is highlighted by the user. The item's text is given.
Inserts the text and userData into the combobox at the given index.
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
Inserts the icon, text and userData into the combobox at the given index.
Inserts the strings from the list into the combobox as separate items, starting at the index specified.
Returns the data for the given role in the given index in the combobox, or QVariant::Invalid if there is no data for this role.
See also setItemData().
Returns the item delegate used by the popup list view.
See also setItemDelegate().
Returns the icon for the given index in the combobox.
See also setItemIcon().
Returns the text for the given index in the combobox.
See also setItemText().
Returns the line edit used to edit items in the combobox, or 0 if there is no line edit.
Only editable combo boxes have a line edit.
See also setLineEdit().
Returns the model used by the combobox.
See also setModel().
Removes the item at the given index from the combobox. This will update the current index if the index is removed.
Returns the root model item index for the items in the combobox.
See also setRootModelIndex().
Sets the text in the combobox's text edit.
Sets the data role for the item on the given index in the combobox to the specified value.
See also itemData().
Sets the item delegate for the popup list view. The combobox takes ownership of the delegate.
See also itemDelegate().
Sets the icon for the item on the given index in the combobox.
See also itemIcon().
Sets the text for the item on the given index in the combobox.
See also itemText().
Sets the line edit to use instead of the current line edit widget.
See also lineEdit().
Sets the model to be model. model must not be 0. If you want to clear the contents of a model, call clear().
Sets the root model item index for the items in the combobox.
See also rootModelIndex().
Sets the validator to use instead of the current validator.
See also validator().
Sets the view to be used in the combobox popup to the given itemView. The combobox takes ownership of the view.
See also view().
Displays the list of items in the combobox. If the list is empty then the no items will be shown.
Returns the validator that is used to constrain text input for the combobox.
See also setValidator() and editable.
Returns the list view used for the combobox popup.
See also setView().
| Copyright © 2005 Trolltech | Trademarks | Qt 4.1.0 |
