¤ windowF

Types

windowF :: [FRequest] -> K a b -> F a b

Synopsis

windowF startcmds fkernel

Description

windowF is used to create ``leaf'' windows, i.e windows that are the basic building blocks, and don't contain any other windows. They are used to create a wide range of basic user interface elements, e.g. displays, input fields, buttons, etc.

Arguments

startcmds :: [FRequest]: a list of low level commands to be executed right after the window is created. This usually includes the ChangeWindowAttributes command to set window attributes. One important window attribute is the event mask, where you typically include things like ExposureMask, ButtonPressMask, KeyPressMask, and so on. (An empty attribute list implies the default event mask, which is the empty event mask.)
fkernel :: K a b: a fudget kernel that determines the behaviour of this window.

Input

connected directly to the kernel.

Output

connected directly to the kernel.

The fudget is expected to cooperate with the dynamic layout mechanism. This amounts to the following:

The fudget must tell how big it wants to be, and whether it wants to be resized dynamically, by soon after creation outputting the pseudo-command LayoutLimits, which has an argument of type LayoutRequest:
```
data LayoutRequest = Layout {minsize :: Size,
                             fixedh :: Bool,
                             fixedv :: Bool,
                             wAdj :: Int -> Size,
                             hAdj :: Int -> Size,
                             refpoints :: [Point],
                             wantedPos :: Maybe (Point, Size, Alignment)}
```
The constructor Layout is used to specify the layout. The first argument to Layout is the minimum initial size of the window. The second and third arguments determine whether the horizontal and vertical size are fixed, respectively. If these are set to True, layout functions of enclosing fudgets will try to keep the size of this window fixed, and let other fudgets change in size if the enclosing shell window is resized. If they are set to False, this fudget is likely to be resized when the enclosing shell window is resized.
When the enclosing shell window is resized, the fudget window will possibly be resized, and the fudget will receive the pseudo-event LayoutSize, the only argument of which is the new size of the window. The fudget should adjust its behaviour accordingly.

Bugs

The startcmds argument is redundant, since the commands could be output by the fudget kernel itself.