QtGui Bindings

The package qtgui contains bindings for classes defined by the Qt module QtGui.

Besides the capabilites reported below, all qt variants inherit a set of default methods, and all qt object classes inherit the capabilities from their superclasses and automatically expose [[qt.md#qt.QObjects|properties, slots and signals]].

qt.QAction, qt.QtLuaAction

Qt class QAction is a sublass of qt.QObject that represents actions associated with menu items and toolbar icons.

qt.QAction([arg])

Expression qt.QAction([arg]) returns a new QAction object. The optional argument arg can be a qt object that becomes the action parent or a table whose members contain initial values for the action properties. This table can also contain a function value which is then connected to the signal triggered(bool) of the qt action object.

Example:

a === qt.QAction { text="Automatic Mode", 
                   checkable === true, checked === false,
                   function(b) setAutoMode(b) end }

Unless a parent is specified, the action is owned by the Lua interpreter and therefore is automatically destroyed when the garbage collector determines that it is no longer referenced.

Actions are always created from the main thread using the thread hopping mechanism.

qaction:menu()

Same as the C++ function QAction::menu().

qaction:setMenu()

Same as the C++ function QAction::setMenu().

qt.QtLuaAction([arg])

This constructor takes the same arguments as qt.QAction but returns an instance of a convenient subclass that enables or disables the action according to the availability of the Lua engine.

The action follows its property enabled when the Lua engine is ready to invoke Lua functions connected to Qt signals. Otherwise the action is disabled regardless of the value of property enabled.

qtluaaction.autoDisable

This property applies only to action objects of class qt.QtLuaAction. It controls whether the action is automatically disabled when the Lua engine is not available. The default is true.

qt.QApplication

Qt class QApplication manages the GUI application's control flow and main settings. This is a subclass of QCoreApplication.

qt.QApplication.changeOverrideCursor(qcursor)

Changes the currently active application override cursor to cursor without disturbing the cursor stack. This function has no effect if setOverrideCursor() was not called.

qt.QApplication.keyboardModifiers()

Returns a string describing the currently depressed keyboard modifiers.

qt.QApplication.mouseButtons()

Returns a string describing the currently depressed mouse buttons.

qt.QApplication.overrideCursor()

Returns the active application override cursor. This function returns nil if no application cursor has been defined (i.e. the internal cursor stack is empty).

qt.QApplication.restoreOverrideCursor()

Undoes the last setOverrideCursor().

qt.QApplication.setOverrideCursor(qcursor)

Sets the application override cursor to qcursor. Application override cursors are intended for showing the user that the application is in a special state, for example during an operation that might take some time. Override cursors are stored on a stack. Function setOverrideCursor() pushes a cursor on the stack. Function restoreOverrideCursor() pops the stack.

qt.QBrush

Qt class QBrush represents the painter settings that determine how shape are filled and how text is rendered. Brushes are represented by Qt variants of class qt.QBrush.

qt.QBrush(table)

Expression qt.QBrush(table) returns a brush whose settings are determined by the fields of table table. The following fields are recognized:

  • Field color contains a qt.QColor value representing the brush color.
  • Field texture contains a qt.QImage value representing the brush texture.
  • Field gradient contains a qt.QGradient value representing a color gradient.
  • Field transform contains a qt.QTransform value that defines a additional transformation applied to the brush before painting it into the current coordinate system.
  • Field style contains the name of the brush style. The default brush style is SolidPatter when field color is defined, TexturePattern when field texture is defined, or one of the gradient styles when field gradient is defined. Otherwise the default style is NoBrush meaning that nothing is painted.

qbrush:totable()

Expression qbrush:totable() returns a table describing the brush. See the documentation of qt.QBrush(table) for a description of the table fields.

qt.QColor

Qt class QColor represents colors for painting purposes. Qt variant of class qt.QColor have a textual representation of the form =="#RRGGBB" where letters R, G, or B are hexadecimal digits representing the intensities of the color components.

qt.QColor(...)

There are several ways to construct a Qt variant of class qt.QColor.

qt.QColor(r,g,b,[a])

Arguments r, g, b, and a are numbers in range [0,1] representing the intensities of the red, green, blue, and alpha channels. The default value for argument a is 1 for a fully opaque color.

qt.QColor(string)

Argument string is a string representing a color name. All SVG color names are recognized.Color names can have also the format "#RGB", "#RRGGBB", "#RRRGGGBBB", or =="#RRRRGGGGBBBB" where letters R, G, or B represent hexadecimal digits for each of the color component.

qt.QColor(table)

Argument table is a table whose fields r, g, b and a contain numbers in range [0,1] representing the intensities of the red, green, blue, and alpha channels. Such a table is returned by function qcolor:totable().

qcolor:totable()

Expression qcolor:totable() returns a table whose fields r, g, b and a contain numbers in range [0,1] representing the intensities of the red, green, blue, and alpha channels.

qt.QColorDialog

Qt class QColorDialog implements a dialog for selecting colors.
The recommended way to use this class is the static function getColor.

qt.QColorDialog.getColor([font],[parent])

Pops up a dialog for selecting a color. Optional argument color is the initial color selection. Argument parent is the parent widget. This function returns nil if the no color was selected. Otherwise it returns a qvariant of type qt.QColor.

qt.QCursor

Qt class QCursor provides a mouse cursor with an arbitrary shape.

qt.QCursor(cursorshape)

Returns a standard cursor. Argument cursorshape is the name of a standard shape.

qt.QCursor(image,[mask],[posx,[posy])

Constructs a cursor with the specified image, mask and hot spot.

qcursor:hotSpot()

Return a qt.QPoint with the cursor's hot spot coordinates.

qcursor:mask()

Return the cursor's mask.

qcursor:pixmap()

Return the cursor's pixmap.

qcursor:shape()

Return the name of the cursor's standard shape.

qt.QCursor.pos()

Returns a QPoint with the global coordinates of the mouse cursor.

qt.QCursor.setPos(qpoint)

Sets the global coordinates of the mouse cursor.

qt.QDialog

Qt class QDialog is the base class of dialog windows.

qt.QDialog([parent])

Expression qt.QDialog(parent) returns a new QDialog instance. The optional argument parent specifies the widget parent. When argument parent is nil or not specified, the new widget is owned by the Lua interpreter and is automatically destroyed when the garbage collector determines that it is no longer referenced.

qdialog:result()

Gets the dialog's result code as an integer. This is usually 1 when the dialog has been accepted and 0 when the dialog has been rejected.

qdialog:setResult(integer)

Sets the dialog's result code. This is usually 1 when the dialog has been accepted and 0 when the dialog has been rejected.

qt.QFileDialog

Qt class QFileDialog provides a dialog that allow users to select files or directories. This is a subclass of qt.QDialog.

qt.QFileDialog.getExistingDirectory([p.[c,[d,[opt]]]])

This convenience function shows a file dialog for selecting an existing directory.

  • Argument p is the parent widget.
  • Argument c is the dialog caption.
  • Argument d is the initial directory shown in the dialog.
  • Argument opt are the file dialog options.

The function returns a qt.QString containing the selected directory name.

qt.QFileDialog.getOpenFileName([p,[c,[d,[f,[s,[opt]]]]]])

This convenience function shows a file dialog for selecting an existing file.

  • Argument p is the parent widget.
  • Argument c is the dialog caption.
  • Argument d is the initial directory shown in the dialog.
  • Argument f contains the filters separated by double semicolons.
  • Argument s contains the selected filter
  • Argument opt are the file dialog options.

The function returns a qt.QString containing the selected file name and a qt.QString contaning the selected filter.

qt.QFileDialog.getOpenFileNames([p,[c,[d,[f,[s,[opt]]]]]])

This convenience function shows a file dialog for selecting multiple existing files.

  • Argument p is the parent widget.
  • Argument c is the dialog caption.
  • Argument d is the initial directory shown in the dialog.
  • Argument f contains the filters separated by double semicolons.
  • Argument s contains the selected filter
  • Argument opt are the file dialog options.

The function returns a qt.QStringList containing the file names and a qt.QString contaning the selected filter.

qt.QFileDialog.getSaveFileName([p,[c,[d,[f,[s,[opt]]]]]])

This convenience function shows a file dialog for selecting a file name for saving data.

  • Argument p is the parent widget.
  • Argument c is the dialog caption.
  • Argument d is the initial directory shown in the dialog.
  • Argument f contains the filters separated by double semicolons.
  • Argument s contains the selected filter
  • Argument opt are the file dialog options.

The function returns a qt.QString containing the selected file name and a qt.QString contaning the selected filter.

qt.QFileDialog.new([parent.[caption,[dir,[filters]]]])

Function qt.QFileDialog.new returns a new file dialog object.

  • Argument parent is the parent widget
  • Argument caption is the dialog caption.
  • Argument dir is the initial directory shown in the dialog.
  • Argument filters contains the filters separated by double semicolons.

When argument parent is nil or not specified, the new widget is owned by the Lua interpreter and is automatically destroyed when the garbage collector determines that it is no longer referenced.

qfiledialog:directory()

Returns a qt.QString containing the path of the selected directory.

qfiledialog:nameFilters()

Returns a qt.QStringList containing the name filters.

qfiledialog:selectedFiles()

Returns a qt.QStringList containing the selected files.

qfiledialog:selectFile(fname)

Select file fname in the file dialog.

qfiledialog:selectNameFilter(filter)

Select name filter filter in the file dialog.

qfiledialog:setDirectory(dirname)

Set the file dialog directory to dirname.

qfiledialog:setNameFilters(filters)

Set the file dialog name filters to filters. Argument filters may be a qt.QStringList or a string containing the filters separated by two semicolons ";;".

qfiledialog:setOption(option, bool)

Sets the specified file dialog option to the boolean value bool. Not available before Qt-4.5.

qfiledialog:testOption(option)

Returns the value of the specified file dialog option. Not available before Qt-4.5.

qt.QFont

Qt class QFont represents the painter settings that determine the font(s) used to display text.

qt.QFont(arg)

Expression qt.QFont(arg) returns a new font object. Argument arg may be a string previously returned by qfont:tostring() or a table whose fields specify the desired font characteristics. The following fields are recognized, listed in order of priority:

  • String field family may contain a comma separated list of the desired font families.
  • Setting boolean field sans to true indicates a preference for sans serif font families such as "Helvetica". This is more portable than specifying a family.
  • Setting boolean field serif to true indicates a preference for serif font families such as "Times". This is more portable than specifying a family.
  • Setting boolean field typewriter to true indicates a preference for a fixed width font families such as "Courier". This is more portable than specifying a family.
  • Numerical field size specify the desired size of the font. The default size is 10 points.
  • Numerical fields pixelSize and pointSize also indicates the desired size of the font. Field pixelSize is an alias for size. Field pointSize includes a correction factor corresponding to the actual resolution of the target device. When both are precised, pointSize takes precedence.
  • Numerical field weight defines the weight of the font. Weight 50 corresponds to a normal font and weight 75 corresponds to a bold font.
  • Numerical field stretch is a percentage applied to the width of all characters. Value 100 corresponds to a normal width. Value 150 increases all width by 50 percent.
  • Setting boolean field bold to true requests a bold font if the selected font family defines a bold variant.
  • Setting boolean field italic to true requests and italic font if the selected font family defines an italic or oblique variant.
  • Setting boolean field fixedPitch to true requests a fixed pitch font if the selected font family defines such a variant (rare).
  • Setting boolean field underline to true draws a line below all the character at a font-specified position.
  • Setting boolean field overline to true draws a line above all the character at a font-specified position.
  • Setting boolean field strikeOut to true draws a line that crosses the character at a font-specified position.

Example:

require 'qtwidget'
w=qtwidget.newwindow(300,300)
w:moveto(20,20)
w:setfont(qt.QFont{serif=true,size=12,italic=true})
w:show("foo")
w:setfont(qt.QFont{serif=true,size=12,italic=true,underline=true})
w:setcolor("blue")
w:show("bar")

qfont:totable()

Expression qfont:totable() returns a table suitable for use with qt.QFont(table). All the supported fields are populated.

Example:

require 'qtwidget'
f=qt.QFont{serif=true,size=12,bold=true}
for k,v in pairs(f:totable()) do print(k,v) end

qfont:tostring()

Expression qfont:tostring() returns a string representation of the font settings that is suitable for storing in configuration files for instance. Use qt.QFont(string) to reconstruct the corresponding font object.

qfont:info()

Expression qfont:info() returns a table describing the actual font selected by the font matching algorithm when one uses qfont to display text on the screen. This table can be used as argument to function qt.QFont() as it uses the same keys.
This is achieved using the Qt class QFontInfo. Fields "underline", "overline", "strikeOut", and "stretch" are copied verbatim from the qfont object.

qt.QFontDialog

Qt class QFontDialog implements a dialog for selecting fonts.
The recommended way to use this class is the static function getFont.

qt.QFontDialog.getFont([font],[parent, [caption]])

Pops up a dialog for selecting a font. All arguments are optional. Argument font is the initial font selection. Argument parent is the parent widget. Argument caption is the dialog window title. This function returns nil if the no font was selected. Otherwise it returns a qvariant of type qt.QFont.

qt.QGradient

Qt class QGradient represents a color gradient for use in gradient brushes. No specific Lua methods have been defined for this Qt variant class.

qt.QIcon

Qt class QIcon provides scalable icons in different modes and states.

qt.QIcon([arg])

Returns a new icon. Argument arg can be a qt value of type qt.QImage or qt.QPixmap. Alternatively, argument arg may be a file name that will be loaded on demand.

qt.QImage

Qt class QImage represents a device independent off-screen image. Such images are represented in Lua as Qt variants of class qt.QImage.

qt.QImage(...)

There are several ways to construct a Qt variant of class qt.QImage.

qt.QImage(w,h,monoflag)

Returns a new image of width w and height h. The image is bitonal when the optional boolean flag monoflag is true. Otherwise the image is a 32 bits RGBA image.

qt.QImage(f,format)

Returns a new image obtained by reading the image file f. Argument f can be a file name or a Lua file descriptor. The file format is determined by the optional string format or by the file name extension.

qimage:depth()

Expression qimage:depth() returns the depth of the image qimage. A depth of 1 indicates a bitonal image. A depth of 24 or 32 indicates a true color image.

qimage:rect()

Expression qimage:rect() returns a Qt variant of class qt.QRect representing the boundaries of the image qimage.

qimage:save(f,[format])

Expression qimage:save(f,format) saves the image data into file f. Argument f can be a file name or a Lua file descriptor. The file format is determined by the optional string format or by the file name extension.

qimage:size()

Expression qimage:size() returns a Qt variant of class qt.QSize representing the size of the image qimage.

qt.QImage.formats([string])

Function qt.QImage.formats describes the supported formats for reading or saving files. The optional string argument must be a string starting with letter "r" or "w" to indicate if one is interested in the supported formats for reading or writing image files. When this letter is followed by letter "f", the function returns a string suitable for selecting name filters in a file dialog. Otherwise, the function returns a qt.QStringList with the supported formats.

qt.QKeySequence

Qt class QKeySequence encapsulates a key sequence as used by shortcuts.

qt.QKeySequence(string)

Returns a Qt value of class qt.QKeySequence associated with the key combination described in string string. Up to four key codes may be entered by separating them with commas, e.g. "Alt+V,Ctrl+Down,A,Shift+Home".

qkeysequence:tostring()

Returns a string describing the keys in the key sequence.

qt.QMainWindow

Qt class QMainWindow provides a main application window with menu, statusbar, toolbars and dockable widgets. This is a subclass of QWidget.

qt.QMainWindow([parent])

Expression qt.QMainWindow(parent) returns a new QMainWindow instance. The optional argument parent specifies the widget parent. When argument parent is nil or not specified, the new widget is owned by the Lua interpreter and is automatically destroyed when the garbage collector determines that it is no longer referenced.

qmainwindow:centralWidget()

Expression qmainwindow:centralWidget() returns the central widget managed by the main window.

qmainwindow:menuBar()

Returns the main window's menu bar. This function creates and returns an empty menu bar if the menu bar does not exist yet.

qmainwindow:setCentralWidget(qwidget)

Sets the widget qwidget to be the main window's central widget. The main window takes ownership of the widget pointer and deletes it at the appropriate time.

qmainwindow:setMenuBar(qmenubar)

Sets the menu bar for the main window to qmenubar. The main window takes ownership of the menu bar and deletes it at the appropriate time.

qmainwindow:setStatusBar(qstatusbar)

Sets the status bar for the main window to qstatusbar. The main window takes ownership of the status bar and deletes it at the appropriate time.

qmainwindow:statusBar()

Returns the main window's status bar. This function creates and returns an empty status bar if the status bar does not exist yet.

qt.QMenu

Qt class QMenu provides a menu widget for use in menu bars, context menus, and other popup menus. This is a subclass of qt.QWidget.

The most flexible way to populate a menu consists of first creating qt.QAction objects for all the menu items. These objects can then be inserted into the menu using the method addAction defined by the superclass QWidget.

Function qmenu:addLuaAction provides a more convenient way to create menu items bound to specific lua functions. See qt.QMenuBar for an example.

qmenu:addLuaAction([icon,]text[,keys[,statustip]][,function])

Creates a new QtLuaAction owned by the menu and appends it to the menu as a new menu item. This function returns the newly created action.

  • Argument icon is an optional qt.QIcon for the action.
  • Argument text specifies the text for the menu item.
  • Argument keys can be either a qt.QKeySequencespecifying the menu item shortcut, or a string representing the shortcut key name.
  • Argument statustip is an optional string that is displayed in the statusbar when the menu item is highlighted. Finally argument function is a Lua function that is connected to the action signal triggered(bool) and therefore is called when the menu item is selected.

qmenu:addMenu(newqmenu)

Adds the menu newqmenu as a submenu of the menu qmenu and returns the corresponding action object.

qmenu:addMenu([icon,] text)

Creates a new submenu with the specified icon and text and adds it into the menu qmenu. This function returns the new menu as an object of class qt.QMenu.

qmenu:addSeparator()

Adds a separator into the menu and returns the corresponding action object.

qmenu:clear()

Removes all the menu items. Actions owned by the menu and not shown in any other widget are deleted.

qmenu:exec([qpoint[, defaultqaction]])

Pops up the menu qmenu at position qpoint and returns the action object corresponding to the selected menu item. This function returns nil if no menu item was selected. Argument defaultqaction specifies which action is located below the mouse cursor when the menu is first shown. Argument qpoint defaults to qmenu.pos.

Note that actions added with qmenu:addLuaAction are automatically disabled while Lua is running. Therefore such actions cannot be used with qmenu:exec because they would all be disabled.

qmenu:insertMenu(beforeqaction, newqmenu)

Inserts the menu newqmenu as a submenu into the menu qmenu and returns the corresponding action object. The submenu is inserted before action beforeqaction or is appended when beforeqaction is null or invalid for this widget.

qmenu:insertSeparator(beforeqaction)

Inserts a new separator before action beforeqaction and returns the corresponding action object.

qmenu:menuAction()

Returns the action associated with the menu qmenu.

qt,QMenuBar

Qt class QMenuBar provides a horizontal menu bar for use in main windows. This is a subclass of qt.QWidget.

Example:

w === qt.QMainWindow()
w:setCentralWidget(...) -- do something smart here
menubar === w:menuBar()
filemenu === menubar:addMenu("&File")
filemenu:addLuaAction("&Open", "Ctrl+O", function() doOpen(w) end)
filemenu:addLuaAction("&Close", "Ctrl+W", function() w:close() end)
editmenu === menubar:addMenu("&Edit")
editmenu:addLuaAction("&Cu&t", "Ctrl+X", function() doCut(w) end)
editmenu:addLuaAction("&Copy", "Ctrl+C", function() doCopy(w) end)
editmenu:addLuaAction("&Paste", "Ctrl+V", function() doPaste(w) end)
w:show()

qmenubar:addMenu(qmenu)

Adds the menu qmenu as a menu of the menubar qmenubar and returns the corresponding action object.

qmenubar:addMenu([icon,] text)

Creates a new menu with the specified icon and text and adds it into the menubar qmenubar. This function returns the new menu as an object of class qt.QMenu.

qmenubar:clear()

Removes all the menus and actions from the menu bar. Actions owned by the menu and not shown in any other widget are deleted.

qmenubar:insertMenu(beforeqaction, qmenu)

Inserts the menu qmenu into the menu bar qmenubar and returns the corresponding action object. The submenu is inserted before action beforeqaction or is appended when beforeqaction is null or invalid for this widget.

qmenubar:insertSeparator(beforeqaction)

Inserts a new separator before action beforeqaction and returns the corresponding action object.

qt.QPainterPath

Qt class QPainterPath represents mathematical boundaries delimiting regions that can be painted using painter:fill or delimited using painter:stroke. No specific Lua methods have been defined for this Qt variant class.

qt.QPixmap

Qt class QPixmap represents a server-side image containing device-dependent data. No specific Lua methods have been defined for this Qt variant class.

qt.QPen

Qt class QPen represents the painter settings that determine how lines are drawn.

qt.QPen(table)

Expression qt.QPen(table) returns a pen whose settings are determined by the fields of table table. The following fields are recognized:

  • Field style specifies the name of the pen style. The default style is SolidLine.
  • Field brush contains a qt.QBrush value that defines the appearance of the painted areas.
  • Field color contains a qt.QColor value for the brush color. Setting this field is equivalent to setting field brush with a solid brush of the specified color. Field brush has precedence over this field.
  • Numerical field width contains the desired line width. A line width of zero indicates a cosmetic pen. This means that the pen width is always drawn one pixel wide, independent of the transformation on the painter.
  • Setting boolean field cosmetic to true indicates that the pen width has a constant width regardless of the transformation on the painter.
  • Field style specifies the name of the pen style which determines
  • Field joinStyle specifies the name of the pen join style which determines how lines meet with different angles. The default join style is BevelJoin.
  • Field capStyle specifies the name of the pen cap style which determines how lines end are drawn. The default cap style is SquareCap.
  • Numerical field miterLimit determines how far a miter join can extend from the join point. This is used to reduce artifacts between line joins where the lines are close to parallel.

qpen:totable()

Expression qpen:totable() returns a table describing the pen. See the documentation of qt.QPen(table) for a description of the table fields.

qt.QTransform

Qt class QTransform represents a 2D transformation of a coordinate system. Transformation matrices are represented as Qt variants of class qt.QTransform.

qt.QTransform([table[,table]])

Expression qt.QTransform() constructs an identity transformation matrix.

Expression qt.QTransform(table) constructs a transformation matrix whose matrix elements are initialized with the fields m11, m12, m13, m21, m22, m23, m31, m32, and m33 of table table.

Expression qt.QTransform(fquad,tquad) constructs a transformation matrix that maps the quad fquad to the quad tquad. Both arguments fquad and tquad are table containing exactly four qt.QPointF representing the four corners of the quad.

qtransform:totable()

Expression qtransform:totable() returns a table suitable for use with expression qt.QTransform(table).

qtransform:scaled(sx,sy)

Function qtransform:scaled returns a new transformation matrix representing a coordinate system whose axes have been scaled by coefficient sx and sy.

qtransform:translated(dx,dy)

Function qtransform:translated returns a new transformation matrix representing a coordinate system whose origin has been translated by dx units along the X axis and dy units along the Y axis.

qtransform:sheared(cx,cy)

Function qtransform:sheared returns a new transformation matrix representing a coordinate system that has been sheared using coefficients cx horizontally and cy vertically.

qtransform:rotated(angle,[axis,[unit]])

Function qtransform:rotated returns a new transformation matrix representing a coordinate system rotated by angle units around the origin. The optional string argument axis may be XAxis, YAxis, or ZAxis and defaults to ZAxis. The optional string argument unit may be Degrees or Radians and default to Degrees.

qtransform:inverted()

Function qtransform:inverted returns the inverse transform of its argument or nil when it is not invertible.

qtransform:map(...)

Function qtransform:map applies a transformation to its argument and returns a new qvariant of the same type. The argument can be a QPoint, QPointF, QLine, QLineF, QPolygon, QPolygonF, QRegion, QPainterPath, QRect, or QRectF. When the argument is a rectangle, the function returns the bounding rectangle of the polygon representing the transformed rectangle. This function also take as argument to reals representing the coordinates of a point and return two reals representing the transformed coordinates.

qt.QWidget

Qt class QWidget is the base class of all graphical interface components. All widgets inherit class qt.QWidget and its superclass qt.QObject.

qt.QWidget([parent])

Expression qt.QWidget(parent) returns a new widget. The optional argument parent specifies the widget parent. New widgets are always created from the main thread using the thread hopping mechanism.

When argument parent is nil or not specified, the new widget is owned by the Lua interpreter and is automatically destroyed when the garbage collector determines that it is no longer referenced.

qwidget:actions()

Expression qwidget:actions() returns a qt value of class qt.QVariantList containing list of actions associated with this widget.

qwidget:addAction(qaction)

Appends action qaction to the list of actions associated with this widget.

Example: creating a context menu

action1 === qt.QtLuaAction{text="Checkme", checkable=true,
            function(b) print("checked:", b) end}
action2 === qt.QtLuaAction{text="Pickme",
            function() print("picked") end}
w:addAction(action1)
w:addAction(action2)
w.contextMenuPolicy='ActionsContextMenu'

qwidget:insertAction(beforeqaction, qaction)

Insert action ==qaction== into the list actions associated with this widget. Argument ==beforeqaction== indicates at which position to insert the action. If ==beforeqaction== is omitted or invalid, the action is simply appended.

qwidget:mapToGlobal(qpoint)

Translates the widget coordinates qpoint to global screen coordinates. Both argument qpoint and the return value are Qt value of class qt.QPoint.

qwidget:mapFromGlobal(qpoint)

Translates the global screen coordinates qpoint to widget coordinates. Both argument qpoint and the return value are Qt value of class qt.QPoint.

qwidget:removeAction(qaction)

Removes action qaction from the list actions associated with this widget.

qwidget:render([pointer])

When called without argument, this function draws the widget into an image and returns the image.

The optional argument pointer can be a pointer to a QPainter or a QPaintDevice where the widget should be rendered. Such pointers can be obtained using functions painter:painter or painter:device. When such an argument is specified, nothing is returned.

qwidget:setAttribute(widgetattribute,[value])

Sets the specified widget attribute to boolean value value. Some of these flags are used internally by Qt. Care is required.

qwidget:setWindowFlag(windowflag,[value])

Sets the specified window flag to boolean value value. Flags indicating a window type are handled as exclusive flags. Setting these flags usually hides the window. You need to do call qwidget:show again.

qwidget:testAttribute(widgetattribute)

Returns a boolean indicating the value of the specified widget attribute. Flags indicating a window type are handled as exclusive flags.

qwidget:testWindowFlag(windowflag)

Returns a boolean indicating the value of the specified window flag. Flags indicating a window type are handled as exclusive flags.

qwidget:window()

Expression qwidget:window() returns the window for widget qwidget, that is the next ancestor that is (or could be) displayed with a window frame.

For instance the following code changes the title of the window containing widget qwidget.

qwidget:window().windowTitle "New Title"