From a6163888f3c56123b1db313743c6147ba498732c Mon Sep 17 00:00:00 2001 From: Yuval Adam Date: Fri, 8 Aug 2014 14:42:07 +0300 Subject: Add third_party libs --- .../windows/fltk-1.1.10/documentation/events.html | 394 +++++++++++++++++++++ 1 file changed, 394 insertions(+) create mode 100644 third_party/windows/fltk-1.1.10/documentation/events.html (limited to 'third_party/windows/fltk-1.1.10/documentation/events.html') diff --git a/third_party/windows/fltk-1.1.10/documentation/events.html b/third_party/windows/fltk-1.1.10/documentation/events.html new file mode 100644 index 0000000..5fac10b --- /dev/null +++ b/third_party/windows/fltk-1.1.10/documentation/events.html @@ -0,0 +1,394 @@ + + + 6 - Handling Events + + + +

6 - Handling Events

+ +

This chapter discusses the FLTK event model and how to handle +events in your program or widget. + +

The FLTK Event Model

+ +

Every time a user moves the mouse pointer, clicks a button, +or presses a key, an event is generated and sent to your +application. Events can also come from other programs like the +window manager. + +

Events are identified by the integer argument passed to the +Fl_Widget::handle() virtual +method. Other information about the most recent event is stored in +static locations and acquired by calling the Fl::event_*() methods. This static +information remains valid until the next event is read from the window +system, so it is ok to look at it outside of the handle() +method. + +

Mouse Events

+ +

FL_PUSH

+ +

A mouse button has gone down with the mouse pointing at this +widget. You can find out what button by calling +Fl::event_button(). You find out the mouse position by +calling Fl::event_x() and Fl::event_y(). + +

A widget indicates that it "wants" the mouse click +by returning non-zero from its handle() method. It +will then become the +Fl::pushed() widget and will get FL_DRAG and +the matching FL_RELEASE events. If handle() +returns zero then FLTK will try sending the FL_PUSH to +another widget.

+ +

FL_DRAG

+ +

The mouse has moved with a button held down. The current +button state is in Fl::event_state(). +The mouse position is in Fl::event_x() and Fl::event_y(). + +

In order to receive FL_DRAG events, the widget must +return non-zero when handling FL_PUSH.

+ +

FL_RELEASE

+ +

A mouse button has been released. You can find out what +button by calling Fl::event_button(). + +

In order to receive the FL_RELEASE event, the widget must +return non-zero when handling FL_PUSH.

+ +

FL_MOVE

+ +

The mouse has moved without any mouse buttons held down. +This event is sent to the Fl::belowmouse() +widget.

+ +

In order to receive FL_MOVE events, the widget must +return non-zero when handling FL_ENTER.

+ +

FL_MOUSEWHEEL

+ +

The user has moved the mouse wheel. The Fl::event_dx() and Fl::event_dy() methods +can be used to find the amount to scroll horizontally and +vertically. + +

Focus Events

+ +

FL_ENTER

+ +

The mouse has been moved to point at this widget. This can +be used for highlighting feedback. If a widget wants to +highlight or otherwise track the mouse, it indicates this by +returning non-zero from its handle() method. It then +becomes the Fl::belowmouse() +widget and will receive FL_MOVE and FL_LEAVE +events. + +

FL_LEAVE

+ +

The mouse has moved out of the widget. + +

In order to receive the FL_LEAVE event, the widget must +return non-zero when handling FL_ENTER.

+ +

FL_FOCUS

+ +

This indicates an attempt to give a widget the +keyboard focus. + +

If a widget wants the focus, it should change itself to +display the fact that it has the focus, and return non-zero from +its handle() +method. It then becomes the Fl::focus() widget and gets +FL_KEYDOWN, FL_KEYUP, and FL_UNFOCUS +events. + +

The focus will change either because the window manager +changed which window gets the focus, or because the user tried +to navigate using tab, arrows, or other keys. You can check Fl::event_key() to +figure out why it moved. For navigation it will be the key +pressed and interaction with the window manager it will be +zero. + +

FL_UNFOCUS

+ +

This event is sent to the previous Fl::focus() widget when +another widget gets the focus or the window loses focus. + +

Keyboard Events

+ +

FL_KEYDOWN, FL_KEYUP

+ +

A key was pressed or released. The key can be found in Fl::event_key(). The +text that the key should insert can be found with Fl::event_text() and +its length is in Fl::event_length(). +If you use the key handle() should return 1. If you +return zero then FLTK assumes you ignored the key and will +then attempt to send it to a parent widget. If none of them want +it, it will change the event into a FL_SHORTCUT event. + +

To receive FL_KEYBOARD events you must also +respond to the FL_FOCUS and FL_UNFOCUS +events. + +

If you are writing a text-editing widget you may also want to +call the Fl::compose() +function to translate individual keystrokes into foreign +characters. + +

FL_KEYUP events are sent to the widget that +currently has focus. This is not necessarily the same widget +that received the corresponding FL_KEYDOWN event +because focus may have changed between events. + +

FL_SHORTCUT

+ +

If the Fl::focus() +widget is zero or ignores an FL_KEYBOARD event then +FLTK tries sending this event to every widget it can, until one +of them returns non-zero. FL_SHORTCUT is first sent to +the Fl::belowmouse() widget, then its parents and +siblings, and eventually to every widget in the window, trying +to find an object that returns non-zero. FLTK tries really hard +to not to ignore any keystrokes! + +

You can also make "global" shortcuts by using Fl::add_handler(). A +global shortcut will work no matter what windows are displayed +or which one has the focus.

+ +

Widget Events

+ +

FL_DEACTIVATE

+ +

This widget is no longer active, due to deactivate() +being called on it or one of its parents. active() may +still be true after this, the widget is only active if +active() is true on it and all its parents (use active_r() to check this). + +

FL_ACTIVATE

+ +

This widget is now active, due to activate() +being called on it or one of its parents. + +

FL_HIDE

+ +

This widget is no longer visible, due to hide() being +called on it or one of its parents, or due to a parent window +being minimized. visible() may still be true after +this, but the widget is visible only if visible() is +true for it and all its parents (use visible_r() to +check this). + +

FL_SHOW

+ +

This widget is visible again, due to show() being +called on it or one of its parents, or due to a parent window +being restored. Child Fl_Windows respond to this by +actually creating the window if not done already, so if you +subclass a window, be sure to pass FL_SHOW to the base +class handle() method! + +

Clipboard Events

+ +

FL_PASTE

+ +

You should get this event some time after you call Fl::paste(). The contents +of Fl::event_text() +is the text to insert and the number of characters is in Fl::event_length(). + +

FL_SELECTIONCLEAR

+ +

The Fl::selection_owner() +will get this event before the selection is moved to another +widget. This indicates that some other widget or program has +claimed the selection. Motif programs used this to clear the +selection indication. Most modern programs ignore this. + +

Drag And Drop Events

+ +

FLTK supports drag and drop of text and files from any +application on the desktop. Text is transfered using +the current code page. Files are received as a list of full path +and file names, separated by newline. On some platforms, path +names are prepended with file://. + +

The drag and drop data is available in Fl::event_text() +at the concluding FL_PASTE. On some platforms, the +event text is also available for the FL_DND_* events, +however application must not depend on that behavior because it +depends on the protocol used on each platform. + +

FL_DND_* events cannot be used in widgets derived +from Fl_Group or Fl_Window. + +

FL_DND_ENTER

+ +

The mouse has been moved to point at this widget. A widget +that is interested in receiving drag'n'drop data must return 1 +to receive FL_DND_DRAG, FL_DND_LEAVE and FL_DND_RELEASE events. + +

FL_DND_DRAG

+ +

The mouse has been moved inside a widget while dragging data. +A widget that is interested in receiving drag'n'drop data should +indicate the possible drop position. + +

FL_DND_LEAVE

+ +

The mouse has moved out of the widget. + +

FL_DND_RELEASE

+ +

The user has released the mouse button dropping data into +the widget. If the widget returns 1, it will receive the data in +the immediately following FL_PASTE event. + + + +

Fl::event_*() methods

+ +

FLTK keeps the information about the most recent event in +static storage. This information is good until the next event is +processed. Thus it is valid inside handle() and +callback() methods. + +

These are all trivial inline functions and thus very fast and small:

+ + + +

Event Propagation

+ +

FLTK follows very simple and unchangeable rules for sending +events. The major innovation is that widgets can indicate (by +returning 0 from the handle() method) that they are not +interested in an event, and FLTK can then send that event +elsewhere. This eliminates the need for "interests" +(event masks or tables), and this is probably the main reason +FLTK is much smaller than other toolkits. + +

Most events are sent directly to the handle() method +of the Fl_Window that the window system says they +belong to. The window (actually the Fl_Group that +Fl_Window is a subclass of) is responsible for sending +the events on to any child widgets. To make the +Fl_Group code somewhat easier, FLTK sends some events +(FL_DRAG, FL_RELEASE, FL_KEYBOARD, +FL_SHORTCUT, FL_UNFOCUS, and +FL_LEAVE) directly to leaf widgets. These procedures +control those leaf widgets: + +

+ +

FLTK Compose-Character Sequences

+ +

The foreign-letter compose processing done by the Fl_Input widget is provided in +a function that you can call if you are writing your own text editor +widget. + +

FLTK uses its own compose processing to allow "preview" of +the partially composed sequence, which is impossible with the +usual "dead key" processing. + +

Although currently only characters in the ISO-8859-1 +character set are handled, you should call this in case any +enhancements to the processing are done in the future. The +interface has been designed to handle arbitrary UTF-8 encoded +text. + +

The following methods are provided for character composition: + +

+ + + -- cgit v1.3.1