OComboBox Class Reference

An enhanced combo box. More...

#include </home/clem/local/src/opie/libopie2/qt3/opieui/ocombobox.h>

Inheritance diagram for OComboBox:

[legend]Collaboration diagram for OComboBox:

[legend]List of all members.


Public Slots
void	rotateText (OCompletionBase::KeyBindingType)
virtual void	setCompletedText (const QString &)
void	setCompletedItems (const QStringList &items)
Signals
void	returnPressed ()
void	returnPressed (const QString &)
void	completion (const QString &)
void	substringCompletion (const QString &)
void	textRotation (OCompletionBase::KeyBindingType)
void	completionModeChanged (OGlobalSettings::Completion)
void	aboutToShowContextMenu (QPopupMenu *)
Public Member Functions
	OComboBox (QWidget parent=0, const char name=0)
	OComboBox (bool rw, QWidget parent=0, const char name=0)
virtual	~OComboBox ()
int	cursorPosition () const
virtual void	setAutoCompletion (bool autocomplete)
bool	autoCompletion () const
virtual void	setContextMenuEnabled (bool showMenu)
bool	isContextMenuEnabled () const
bool	contains (const QString &text) const
void	setTrapReturnKey (bool trap)
bool	trapReturnKey () const
virtual bool	eventFilter (QObject , QEvent )
OCompletionBox *	completionBox (bool create=true)
virtual void	setLineEdit (OLineEdit *)
void	setCurrentItem (const QString &item, bool insert=false, int index=-1)
void	setCurrentItem (int index)
Protected Slots
virtual void	itemSelected (QListBoxItem *)
virtual void	makeCompletion (const QString &)
Protected Member Functions
virtual void	setCompletedText (const QString &, bool)
virtual void	create (WId=0, bool initializeWindow=true, bool destroyOldWindow=true)
Private Types
enum	MenuID { Default = 0, Cut, Copy, Paste, Clear, Unselect, SelectAll, NoCompletion, AutoCompletion, ShellCompletion, PopupCompletion, SemiAutoCompletion }
Private Member Functions
void	init ()
void	deleteWordBack ()
void	deleteWordForward ()
Private Attributes
bool	m_bEnableMenu
bool	m_trapReturnKey
OComboBoxPrivate *	d
Classes
class	OComboBoxPrivate

Detailed Description

An enhanced combo box.

A combined button, line-edit and a popup list widget.

Detail

This widget inherits from QComboBox and implements the following additional functionalities: a completion object that provides both automatic and manual text completion as well as text rotation features, configurable key-bindings to activate these features, and a popup-menu item that can be used to allow the user to set text completion modes on the fly based on their preference.

To support these new features OComboBox also emits a few more additional signals as well. The main ones are the completion( const QString& ) and textRotation( KeyBindingType ) signals. The completion signal is intended to be connected to a slot that will assist the user in filling out the remaining text while the rotation signals is intended to be used to traverse through all possible matches whenever text completion results in multiple matches. The returnPressed() and returnPressed( const QString& ) signal is emitted when the user presses the Enter/Return key.

This widget by default creates a completion object when you invoke the completionObject( bool ) member function for the first time or use setCompletionObject( OCompletion*, bool ) to assign your own completion object. Additionally, to make this widget more functional, OComboBox will by default handle the text rotation and completion events internally whenever a completion object is created through either one of the methods mentioned above. If you do not need this functionality, simply use OCompletionBase::setHandleSignals( bool ) or alternatively set the boolean parameter in the above methods to FALSE.

The default key-bindings for completion and rotation is determined from the global settings in OStdAccel. These values, however, can be overriden locally by invoking OCompletionBase::setKeyBinding(). The values can easily be reverted back to the default setting, by simply calling useGlobalSettings(). An alternate method would be to default individual key-bindings by usning setKeyBinding() with the default second argument.

Note that if this widget is not editable ( i.e. select-only ), then only one completion mode, CompletionAuto, will work. All the other modes are simply ignored. The CompletionAuto mode in this case allows you to automatically select an item from the list by trying to match the pressed keycode with the first letter of the enteries in the combo box.

Usage

To enable the basic completion feature:

 OComboBox *combo = new OComboBox( true, this, "mywidget" );
 OCompletion *comp = combo->completionObject();
 // Connect to the return pressed signal - optional
 connect(combo,SIGNAL(returnPressed(const QString&)),comp,SLOT(addItem(const QString&));

To use your own completion object:

 OComboBox *combo = new OComboBox( this,"mywidget" );
 OURLCompletion *comp = new OURLCompletion();
 combo->setCompletionObject( comp );
 // Connect to the return pressed signal - optional
 connect(combo,SIGNAL(returnPressed(const QString&)),comp,SLOT(addItem(const QString&));

Note that you have to either delete the allocated completion object when you don't need it anymore, or call setAutoDeleteCompletionObject( true );

Miscellaneous function calls:

 // Tell the widget not to handle completion and rotation
 combo->setHandleSignals( false );
 // Set your own completion key for manual completions.
 combo->setKeyBinding( OCompletionBase::TextCompletion, Qt::End );
 // Hide the context (popup) menu
 combo->setContextMenuEnabled( false );
 // Temporarly disable signal emition
 combo->disableSignals();
 // Default the all key-bindings to their system-wide settings.
 combo->useGlobalKeyBindings();

Author:: Dawit Alemayehu <adawit@kde.org>

Definition at line 143 of file ocombobox.h.

Member Enumeration Documentation

enum OComboBox::MenuID [private]

Enumeration values:

Default

Cut

Copy

Paste

Clear

Unselect

SelectAll

NoCompletion

AutoCompletion

ShellCompletion

PopupCompletion

SemiAutoCompletion

Definition at line 501 of file ocombobox.h.

Constructor & Destructor Documentation

OComboBox::OComboBox ( QWidget * parent = 0,

const char * name = 0

)

Constructs a read-only or rather select-only combo box with a parent object and a name.

Parameters:

parent The parent object of this widget

name The name of this widget

Definition at line 68 of file ocombobox.cpp.
References init().

OComboBox::OComboBox ( bool rw,

QWidget * parent = 0,

const char * name = 0

)

Constructs a "read-write" or "read-only" combo box depending on the value of the first argument( rw ) with a parent, a name.

Parameters:

rw When true, widget will be editable.

parent The parent object of this widget.

name The name of this widget.

Definition at line 74 of file ocombobox.cpp.
References init(), and setLineEdit().

OComboBox::~OComboBox ( ) [virtual]

Destructor.
Definition at line 86 of file ocombobox.cpp.
References d.

Member Function Documentation

void OComboBox::aboutToShowContextMenu ( QPopupMenu * ) [signal]

Emitted before the context menu is displayed.
The signal allows you to add your own entries into the the context menu that is created on demand.
NOTE: Do not store the pointer to the QPopupMenu provided through since it is created and deleted on demand.

Parameters:

the context menu about to be displayed

Referenced by OHistoryCombo::init(), and setLineEdit().

bool OComboBox::autoCompletion ( ) const [inline]

Re-implemented from QComboBox.
Returns true if the current completion mode is set to automatic. See its more comprehensive replacement completionMode().

Returns:
true when completion mode is automatic.

Definition at line 245 of file ocombobox.h.
References OCompletionBase::completionMode().

void OComboBox::completion ( const QString & ) [signal]

This signal is emitted when the completion key is pressed.
The argument is the current text being edited.
Note that this signal is not available if this widget is non-editable or the completion mode is set to OGlobalSettings::CompletionNone.
Referenced by setLineEdit().

OCompletionBox * OComboBox::completionBox ( bool create = true )

Returns:
the completion-box, that is used in completion mode OGlobalSettings::CompletionPopup and OGlobalSettings::CompletionPopupAuto. This method will create a completion-box by calling OLineEdit::completionBox, if none is there, yet.

Parameters:

create Set this to false if you don't want the box to be created i.e. to test if it is available.

Definition at line 305 of file ocombobox.cpp.
References OLineEdit::completionBox(), d, and OComboBox::OComboBoxPrivate::olineEdit.

void OComboBox::completionModeChanged ( OGlobalSettings::Completion ) [signal]

Emitted when the user changed the completion mode by using the popupmenu.
Referenced by setLineEdit().

bool OComboBox::contains ( const QString & text ) const

Convenience method which iterates over all items and checks if any of them is equal to text.
If text is an empty string, false is returned.

Returns:
true if an item with the string text is in the combobox.

Definition at line 116 of file ocombobox.cpp.
References i, and text.
Referenced by OHistoryCombo::addToHistory().

void OComboBox::create ( WId = 0,

bool initializeWindow = true,

bool destroyOldWindow = true

) [protected, virtual]

Reimplemented for internal reasons, the API is not affected.
Definition at line 313 of file ocombobox.cpp.

int OComboBox::cursorPosition ( ) const [inline]

Returns the current cursor position.
This method always returns a -1 if the combo-box is not editable (read-write).

Returns:
Current cursor position.

Definition at line 222 of file ocombobox.h.

void OComboBox::deleteWordBack ( ) [private]

Temporary functions to delete words back and foward until alternatives are available in QT3 (Seth Chaiklin, 21 may 2001)
Definition at line 365 of file ocombobox.cpp.
References hasSelectedText(), and TRUE.

void OComboBox::deleteWordForward ( ) [private]

Definition at line 352 of file ocombobox.cpp.
References hasSelectedText(), and TRUE.

bool OComboBox::eventFilter ( QObject * ,

QEvent *

) [virtual]

Re-implemented for internal reasons. API not affected.
Definition at line 202 of file ocombobox.cpp.
References OLineEdit::completionBox(), d, KeyPress, m_trapReturnKey, OComboBox::OComboBoxPrivate::olineEdit, returnPressed(), setCurrentItem(), text, and type.

void OComboBox::init ( ) [private]

Initializes the variables upon construction.
Definition at line 91 of file ocombobox.cpp.
References d, m_bEnableMenu, m_trapReturnKey, and setContextMenuEnabled().
Referenced by OComboBox(), and OHistoryCombo::OHistoryCombo().

bool OComboBox::isContextMenuEnabled ( ) const [inline]

Returns true when the context menu is enabled.
Definition at line 270 of file ocombobox.h.
References m_bEnableMenu.

virtual void OComboBox::itemSelected ( QListBoxItem * ) [inline, protected, virtual, slot]

Deprecated:

Definition at line 465 of file ocombobox.h.

void OComboBox::makeCompletion ( const QString & ) [protected, virtual, slot]

Completes text according to the completion mode.
Note: this method is not invoked if the completion mode is set to CompletionNone. Also if the mode is set to CompletionShell and multiple matches are found, this method will complete the text to the first match with a beep to inidicate that there are more matches. Then any successive completion key event iterates through the remaining matches. This way the rotation functionality is left to iterate through the list as usual.
Definition at line 179 of file ocombobox.cpp.
References d, OLineEdit::makeCompletion(), OComboBox::OComboBoxPrivate::olineEdit, and setCurrentItem().

void OComboBox::returnPressed ( const QString & ) [signal]

Emitted when the user presses the Enter key.
The argument is the current text being edited. This signal is just like returnPressed() except it contains the current text as its argument.
Note that this signal is only emitted if this widget is editable.

void OComboBox::returnPressed ( ) [signal]

Emitted when the user presses the Enter key.
Note that this signal is only emitted if this widget is editable.
Referenced by eventFilter(), and OHistoryCombo::init().

void OComboBox::rotateText ( OCompletionBase::KeyBindingType ) [slot]

Iterates through all possible matches of the completed text or the history list.
Depending on the value of the argument, this function either iterates through the history list of this widget or the all possible matches in whenever multiple matches result from a text completion request. Note that the all-possible-match iteration will not work if there are no previous matches, i.e. no text has been completed and the *nix shell history list rotation is only available if the insertion policy for this widget is set either QComobBox::AtTop or QComboBox::AtBottom. For other insertion modes whatever has been typed by the user when the rotation event was initiated will be lost.

Parameters:

type The key-binding invoked.

Definition at line 196 of file ocombobox.cpp.
References d, OComboBox::OComboBoxPrivate::olineEdit, and OLineEdit::rotateText().

void OComboBox::setAutoCompletion ( bool autocomplete ) [virtual]

Re-implemented from QComboBox.
If true, the completion mode will be set to automatic. Otherwise, it is defaulted to the global setting. This method has been replaced by the more comprehensive setCompletionMode().

Parameters:

autocomplete Flag to enable/disable automatic completion mode.

Definition at line 128 of file ocombobox.cpp.
References d, OComboBox::OComboBoxPrivate::olineEdit, OCompletionBase::setCompletionMode(), and OLineEdit::setCompletionMode().

void OComboBox::setCompletedItems ( const QStringList & items ) [virtual, slot]

Sets items into the completion-box if completionMode() is CompletionPopup. The popup will be shown immediately.
Implements OCompletionBase.
Definition at line 298 of file ocombobox.cpp.
References d, OComboBox::OComboBoxPrivate::olineEdit, and OLineEdit::setCompletedItems().

void OComboBox::setCompletedText ( const QString & ,

bool

) [protected, virtual]

Definition at line 167 of file ocombobox.cpp.
References d, OComboBox::OComboBoxPrivate::olineEdit, and OLineEdit::setCompletedText().

void OComboBox::setCompletedText ( const QString & ) [virtual, slot]

Sets the completed text in the line-edit appropriately.
This function is an implementation for OCompletionBase::setCompletedText.
Implements OCompletionBase.
Definition at line 173 of file ocombobox.cpp.
References d, OComboBox::OComboBoxPrivate::olineEdit, and OLineEdit::setCompletedText().

void OComboBox::setContextMenuEnabled ( bool showMenu ) [virtual]

Enables or disable the popup (context) menu.
This method only works if this widget is editable, i.e. read-write and allows you to enable/disable the context menu. It does nothing if invoked for a none-editable combo-box. Note that by default the mode changer item is made visiable whenever the context menu is enabled. Use hideModechanger() if you want to hide this item. Also by default, the context menu is created if this widget is editable. Call this function with the argument set to false to disable the popup menu.

Parameters:

showMenu If true, show the context menu.

showMode If true, show the mode changer.

Definition at line 145 of file ocombobox.cpp.
References d, m_bEnableMenu, OComboBox::OComboBoxPrivate::olineEdit, and OLineEdit::setContextMenuEnabled().
Referenced by init().

void OComboBox::setCurrentItem ( int index )

Definition at line 398 of file ocombobox.cpp.

void OComboBox::setCurrentItem ( const QString & item,

bool insert = false,

int index = -1

)

Selects the first item that matches item. If there is no such item, it is inserted at position index if insert is true. Otherwise, no item is selected.
Definition at line 378 of file ocombobox.cpp.
References i, and text.
Referenced by eventFilter(), and makeCompletion().

void OComboBox::setLineEdit ( OLineEdit * ) [virtual]

Definition at line 319 of file ocombobox.cpp.
References aboutToShowContextMenu(), completion(), completionModeChanged(), d, OComboBox::OComboBoxPrivate::olineEdit, OCompletionBase::setDelegate(), substringCompletion(), and textRotation().
Referenced by OComboBox().

void OComboBox::setTrapReturnKey ( bool trap )

By default, OComboBox recognizes Key_Return and Key_Enter and emits the returnPressed() signals, but it also lets the event pass, for example causing a dialog's default-button to be called.
Call this method with trap equal to true to make OComboBox stop these events. The signals will still be emitted of course.
Only affects read-writable comboboxes.

See also:
setTrapReturnKey()

Definition at line 260 of file ocombobox.cpp.
References m_trapReturnKey.

void OComboBox::substringCompletion ( const QString & ) [signal]

Emitted when the shortcut for substring completion is pressed.
Referenced by setLineEdit().

void OComboBox::textRotation ( OCompletionBase::KeyBindingType ) [signal]

Emitted when the text rotation key-bindings are pressed.
The argument indicates which key-binding was pressed. In this case this can be either one of four values: PrevCompletionMatch, NextCompletionMatch, RotateUp or RotateDown. See OCompletionBase::setKeyBinding() for details.
Note that this signal is NOT emitted if the completion mode is set to CompletionNone.
Referenced by setLineEdit().

bool OComboBox::trapReturnKey ( ) const

Returns:
true if keyevents of Key_Return or Key_Enter will be stopped or if they will be propagated.

See also:
setTrapReturnKey ()

Definition at line 265 of file ocombobox.cpp.
References m_trapReturnKey.