Module Graphics.UI

Exported Datatypes

The port to a GUI is just the stream connection to a GUI where Tcl/Tk communication is done.

The type of possible widgets in a GUI.

Constructors:

• PlainButton :: [ConfItem] -> Widget
  a button in a GUI whose event handler is activated if the user presses the button
• Canvas :: [ConfItem] -> Widget
  a canvas to draw pictures containing CanvasItems
• CheckButton :: [ConfItem] -> Widget
  a check button: it has value "0" if it is unchecked and value "1" if it is checked
• Entry :: [ConfItem] -> Widget
  an entry widget for entering single lines
• Label :: [ConfItem] -> Widget
  a label for showing a text
• ListBox :: [ConfItem] -> Widget
  a widget containing a list of items for selection
• Message :: [ConfItem] -> Widget
  a message for showing simple string values
• MenuButton :: [ConfItem] -> Widget
  a button with a pull-down menu
• Scale :: Int -> Int -> [ConfItem] -> Widget
  a scale widget to input values by a slider
• ScrollH :: WidgetRef -> [ConfItem] -> Widget
  a horizontal scroll bar
• ScrollV :: WidgetRef -> [ConfItem] -> Widget
  a vertical scroll bar
• TextEdit :: [ConfItem] -> Widget
  a text editor widget to show and manipulate larger text paragraphs
• Row :: [ConfCollection] -> [Widget] -> Widget
  a horizontal alignment of widgets
• Col :: [ConfCollection] -> [Widget] -> Widget
  a vertical alignment of widgets
• Matrix :: [ConfCollection] -> [[Widget]] -> Widget
  a 2-dimensional (matrix) alignment of widgets

The data type for possible configurations of a widget.

Constructors:

• Active :: Bool -> ConfItem
  define the active state for buttons, entries, etc.
• Anchor :: String -> ConfItem
  alignment of information inside a widget where the argument must be: n, ne, e, se, s, sw, w, nw, or center
• Background :: String -> ConfItem
  the background color
• Foreground :: String -> ConfItem
  the foreground color
• Handler :: Event -> (GuiPort -> IO [ReconfigureItem]) -> ConfItem
  an event handler associated to a widget. The event handler returns a list of widget ref/configuration pairs that are applied after the handler in order to configure GUI widgets
• Height :: Int -> ConfItem
  the height of a widget (chars for text, pixels for graphics)
• CheckInit :: String -> ConfItem
  initial value for checkbuttons
• CanvasItems :: [CanvasItem] -> ConfItem
  list of items contained in a canvas
• List :: [String] -> ConfItem
  list of values shown in a listbox
• Menu :: [MenuItem] -> ConfItem
  the items of a menu button
• WRef :: WidgetRef -> ConfItem
  a reference to this widget
• Text :: String -> ConfItem
  an initial text contents
• Width :: Int -> ConfItem
  the width of a widget (chars for text, pixels for graphics)
• Fill :: ConfItem
  fill widget in both directions
• FillX :: ConfItem
  fill widget in horizontal direction
• FillY :: ConfItem
  fill widget in vertical direction
• TclOption :: String -> ConfItem
  further options in Tcl syntax (unsafe!)

Data type for describing configurations that are applied to a widget or GUI by some event handler.

Constructors:

• WidgetConf :: WidgetRef -> ConfItem -> ReconfigureItem
  wref conf - reconfigure the widget referred by wref with configuration item conf
• StreamHandler :: Handle -> (Handle -> GuiPort -> IO [ReconfigureItem]) -> ReconfigureItem
  hdl handler - add a new handler to the GUI that processes inputs on an input stream referred by hdl
• RemoveStreamHandler :: Handle -> ReconfigureItem
  hdl - remove a handler for an input stream referred by hdl from the GUI (usually used to remove handlers for closed streams)

The data type of possible events on which handlers can react. This list is still incomplete and might be extended or restructured in future releases of this library.

Constructors:

• DefaultEvent :: Event
  the default event of the widget
• MouseButton1 :: Event
  left mouse button pressed
• MouseButton2 :: Event
  middle mouse button pressed
• MouseButton3 :: Event
  right mouse button pressed
• KeyPress :: Event
  any key is pressed
• Return :: Event
  return key is pressed

Known instances:

• Eq Event

The data type for possible configurations of widget collections (e.g., columns, rows).

Constructors:

• CenterAlign :: ConfCollection
  centered alignment
• LeftAlign :: ConfCollection
  left alignment
• RightAlign :: ConfCollection
  right alignment
• TopAlign :: ConfCollection
  top alignment
• BottomAlign :: ConfCollection
  bottom alignment

The data type for specifying items in a menu.

Constructors:

• MButton :: (GuiPort -> IO [ReconfigureItem]) -> String -> MenuItem
  a button with an associated command and a label string
• MSeparator :: MenuItem
  a separator between menu entries
• MMenuButton :: String -> [MenuItem] -> MenuItem
  a submenu with a label string

The data type of items in a canvas. The last argument are further options in Tcl/Tk (for testing).

Constructors:

• CLine :: [(Int, Int)] -> String -> CanvasItem
• CPolygon :: [(Int, Int)] -> String -> CanvasItem
• CRectangle :: (Int, Int) -> (Int, Int) -> String -> CanvasItem
• COval :: (Int, Int) -> (Int, Int) -> String -> CanvasItem
• CText :: (Int, Int) -> String -> String -> CanvasItem

The (hidden) data type of references to a widget in a GUI window. Note that the constructor WRefLabel will not be exported so that values can only be created inside this module.

The data type of possible text styles.

Constructors:

• Bold :: Style
  text in bold font
• Italic :: Style
  text in italic font
• Underline :: Style
  underline text
• Fg :: Color -> Style
  foreground color, i.e., color of the text font
• Bg :: Color -> Style
  background color of the text

The data type of possible colors.

Constructors:

• Black :: Color
• Blue :: Color
• Brown :: Color
• Cyan :: Color
• Gold :: Color
• Gray :: Color
• Green :: Color
• Magenta :: Color
• Navy :: Color
• Orange :: Color
• Pink :: Color
• Purple :: Color
• Red :: Color
• Tomato :: Color
• Turquoise :: Color
• Violet :: Color
• White :: Color
• Yellow :: Color

Exported Functions

row :: [Widget] -> Widget   

Horizontal alignment of widgets.

Further infos:

• solution complete, i.e., able to compute all solutions

col :: [Widget] -> Widget   

Vertical alignment of widgets.

Further infos:

• solution complete, i.e., able to compute all solutions

matrix :: [[Widget]] -> Widget   

Matrix alignment of widgets.

Further infos:

• solution complete, i.e., able to compute all solutions

debugTcl :: Widget -> IO ()   

Prints the generated Tcl commands of a main widget (useful for debugging).

Further infos:

• might behave indeterministically

runPassiveGUI :: String -> Widget -> IO GuiPort   

IO action to show a Widget in a new GUI window in passive mode, i.e., ignore all GUI events.

Further infos:

• might behave indeterministically

runGUI :: String -> Widget -> IO ()   

IO action to run a Widget in a new window.

Further infos:

• might behave indeterministically

runGUIwithParams :: String -> String -> Widget -> IO ()   

IO action to run a Widget in a new window.

Further infos:

• might behave indeterministically

runInitGUI :: String -> Widget -> (GuiPort -> IO [ReconfigureItem]) -> IO ()   

IO action to run a Widget in a new window. The GUI events are processed after executing an initial action on the GUI.

Further infos:

• might behave indeterministically

runInitGUIwithParams :: String -> String -> Widget -> (GuiPort -> IO [ReconfigureItem]) -> IO ()   

IO action to run a Widget in a new window. The GUI events are processed after executing an initial action on the GUI.

Further infos:

• might behave indeterministically

runControlledGUI :: String -> (Widget, String -> GuiPort -> IO ()) -> Handle -> IO ()   

Runs a Widget in a new GUI window and process GUI events. In addition, an event handler is provided that process messages received from an external stream identified by a handle (third argument). This operation is useful to run a GUI that should react on user events as well as messages written to the given handle.

Further infos:

• might behave indeterministically

runConfigControlledGUI :: String -> (Widget, String -> GuiPort -> IO [ReconfigureItem]) -> Handle -> IO ()   

Runs a Widget in a new GUI window and process GUI events. In addition, an event handler is provided that process messages received from an external stream identified by a handle (third argument). This operation is useful to run a GUI that should react on user events as well as messages written to the given handle.

Further infos:

• might behave indeterministically

runInitControlledGUI :: String -> (Widget, String -> GuiPort -> IO ()) -> (GuiPort -> IO [ReconfigureItem]) -> Handle -> IO ()   

Runs a Widget in a new GUI window and process GUI events after executing an initial action on the GUI window. In addition, an event handler is provided that process messages received from an external message stream. This operation is useful to run a GUI that should react on user events as well as messages written to the given handle.

Further infos:

• might behave indeterministically

runHandlesControlledGUI :: String -> (Widget, [Handle -> GuiPort -> IO [ReconfigureItem]]) -> [Handle] -> IO ()   

Runs a Widget in a new GUI window and process GUI events. In addition, a list of event handlers is provided that process inputs received from a corresponding list of handles to input streams. Thus, if the i-th handle has some data available, the i-th event handler is executed with the i-th handle as a parameter. This operation is useful to run a GUI that should react on inputs provided by other processes, e.g., via sockets.

Further infos:

• might behave indeterministically

runInitHandlesControlledGUI :: String -> (Widget, [Handle -> GuiPort -> IO [ReconfigureItem]]) -> (GuiPort -> IO [ReconfigureItem]) -> [Handle] -> IO ()   

Runs a Widget in a new GUI window and process GUI events after executing an initial action on the GUI window. In addition, a list of event handlers is provided that process inputs received from a corresponding list of handles to input streams. Thus, if the i-th handle has some data available, the i-th event handler is executed with the i-th handle as a parameter. This operation is useful to run a GUI that should react on inputs provided by other processes, e.g., via sockets.

Further infos:

• might behave indeterministically

setConfig :: WidgetRef -> ConfItem -> GuiPort -> IO ()   

Changes the current configuration of a widget (deprecated operation, only included for backward compatibility). Warning: does not work for Command options!

Further infos:

• might behave indeterministically

exitGUI :: GuiPort -> IO ()   

An event handler for terminating the GUI.

getValue :: WidgetRef -> GuiPort -> IO String   

Gets the (String) value of a variable in a GUI.

setValue :: WidgetRef -> String -> GuiPort -> IO ()   

Sets the (String) value of a variable in a GUI.

updateValue :: (String -> String) -> WidgetRef -> GuiPort -> IO ()   

Updates the (String) value of a variable w.r.t. to an update function.

appendValue :: WidgetRef -> String -> GuiPort -> IO ()   

Appends a String value to the contents of a TextEdit widget and adjust the view to the end of the TextEdit widget.

Further infos:

• might behave indeterministically

appendStyledValue :: WidgetRef -> String -> [Style] -> GuiPort -> IO ()   

Appends a String value with style tags to the contents of a TextEdit widget and adjust the view to the end of the TextEdit widget. Different styles can be combined, e.g., to get bold blue text on a red background. If codeBold/code, codeItalic/code and codeUnderline/code are combined, currently all but one of these are ignored. This is an experimental function and might be changed in the future.

Further infos:

• might behave indeterministically

addRegionStyle :: WidgetRef -> (Int, Int) -> (Int, Int) -> Style -> GuiPort -> IO ()   

Adds a style value in a region of a TextEdit widget. The region is specified a start and end position similarly to codegetCursorPosition/code. Different styles can be combined, e.g., to get bold blue text on a red background. If codeBold/code, codeItalic/code and codeUnderline/code are combined, currently all but one of these are ignored. This is an experimental function and might be changed in the future.

Further infos:

• might behave indeterministically

removeRegionStyle :: WidgetRef -> (Int, Int) -> (Int, Int) -> Style -> GuiPort -> IO ()   

Removes a style value in a region of a TextEdit widget. The region is specified a start and end position similarly to codegetCursorPosition/code. This is an experimental function and might be changed in the future.

Further infos:

• might behave indeterministically

getCursorPosition :: WidgetRef -> GuiPort -> IO (Int, Int)   

Get the position (line,column) of the insertion cursor in a TextEdit widget. Lines are numbered from 1 and columns are numbered from 0.

seeText :: WidgetRef -> (Int, Int) -> GuiPort -> IO ()   

Adjust the view of a TextEdit widget so that the specified line/column character is visible. Lines are numbered from 1 and columns are numbered from 0.

Further infos:

• might behave indeterministically

focusInput :: WidgetRef -> GuiPort -> IO ()   

Sets the input focus of this GUI to the widget referred by the first argument. This is useful for automatically selecting input entries in an application.

addCanvas :: WidgetRef -> [CanvasItem] -> GuiPort -> IO ()   

Adds a list of canvas items to a canvas referred by the first argument.

Further infos:

• might behave indeterministically

popupMessage :: String -> IO ()   

A simple popup message.

Further infos:

• might behave indeterministically

Cmd :: (GuiPort -> IO ()) -> ConfItem   

A simple event handler that can be associated to a widget. The event handler takes a GUI port as parameter in order to read or write values from/into the GUI.

Command :: (GuiPort -> IO [ReconfigureItem]) -> ConfItem   

An event handler that can be associated to a widget. The event handler takes a GUI port as parameter (in order to read or write values from/into the GUI) and returns a list of widget reference/configuration pairs which is applied after the handler in order to configure some GUI widgets.

Further infos:

• solution complete, i.e., able to compute all solutions

Button :: (GuiPort -> IO ()) -> [ConfItem] -> Widget   

A button with an associated event handler which is activated if the button is pressed.

ConfigButton :: (GuiPort -> IO [ReconfigureItem]) -> [ConfItem] -> Widget   

A button with an associated event handler which is activated if the button is pressed. The event handler is a configuration handler (see Command) that allows the configuration of some widgets.

Further infos:

• solution complete, i.e., able to compute all solutions

TextEditScroll :: [ConfItem] -> Widget   

A text edit widget with vertical and horizontal scrollbars. The argument contains the configuration options for the text edit widget.

ListBoxScroll :: [ConfItem] -> Widget   

A list box widget with vertical and horizontal scrollbars. The argument contains the configuration options for the list box widget.

CanvasScroll :: [ConfItem] -> Widget   

A canvas widget with vertical and horizontal scrollbars. The argument contains the configuration options for the text edit widget.

EntryScroll :: [ConfItem] -> Widget   

An entry widget with a horizontal scrollbar. The argument contains the configuration options for the entry widget.

getOpenFile :: IO String   

Pops up a GUI for selecting an existing file. The file with its full path name will be returned (or "" if the user cancels the selection).

getOpenFileWithTypes :: [(String, String)] -> IO String   

Pops up a GUI for selecting an existing file. The parameter is a list of pairs of file types that could be selected. A file type pair consists of a name and an extension for that file type. The file with its full path name will be returned (or "" if the user cancels the selection).

getSaveFile :: IO String   

Pops up a GUI for choosing a file to save some data. If the user chooses an existing file, she/he will asked to confirm to overwrite it. The file with its full path name will be returned (or "" if the user cancels the selection).

getSaveFileWithTypes :: [(String, String)] -> IO String   

Pops up a GUI for choosing a file to save some data. The parameter is a list of pairs of file types that could be selected. A file type pair consists of a name and an extension for that file type. If the user chooses an existing file, she/he will asked to confirm to overwrite it. The file with its full path name will be returned (or "" if the user cancels the selection).

chooseColor :: IO String   

Pops up a GUI dialog box to select a color. The name of the color will be returned (or "" if the user cancels the selection).