scroller.gadget Reference¶

Comprehensive function reference for scroller.gadget, synthesised from the AmigaOS NDK 3.2 Release 4 (Autodocs/scroller).

This page documents 2 functions of scroller.gadget. Each function entry follows the canonical autodoc format. struct Name, union Name, enum Name are clickable links to the type definition in the types reference.

Function index¶

• scroller_gc()
• SCROLLER_GetClass()

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scroller_gc()¶

**scroller_gc -- create scroller BOOPSI objects

SUPERCLASS
    gadgetclass

REQUIRES
    bevel.image, glyph.image

DESCRIPTION
    The scroller gadget is a propgclass wrapper class and is used
    to create proportional scroller or linear slider gadgets.
    To create a linear slider, SCROLLER_Visible must be set to 1, and
    SCROLLER_Top will range in value from 0 to SCROLLER_Total - 1.

    The IntuiMessage.Code field will contain the SCROLLER_Top
    attribute, cast to a WORD.

    Advantages that this class provides are:

     > Supports window relativity.

     > Supports OS 3.0 BOOPSI Notification/Update.

     > Special signaling ability.

     > Optional scroller arrow buttons.

     > Supports usage in window boarders.

METHODS
    OM_NEW -- Create the scroller gadget. Also allocates an
        instance of the bevel and glyph image classes.
        Passed to superclass then calls OM_SET.

    OM_SET -- Set object attributes. Passed to superclass first.

    OM_DISPOSE -- Frees up the scroller gadget as well as the
        bevel and glyph image instances. Passed to superclass last.

    OM_UPDATE -- Set object notification attributes. Passed to
        superclass first.

    GM_RENDER -- Renders the gadget imagery. Overrides the superclass.

    GM_GOACTIVE -- Handles activation. Overrides the superclass.

    GM_HANDLEINPUT -- Handles input events once active. Overrides
        the superclass.

    GM_GOINACTIVE -- Overrides the superclass. Handles deactivation.

    GM_HELPTEST -- Test if mouse is within gadget hit area.

    GM_HITTEST -- Test if mouse is within gadget hit area.

    GM_DOMAIN -- Returns GDOMAIN_MINIMUM and GDOMAIN_MAXIMUM dimensions.

    All other methods are passed to the superclass.

ATTRIBUTES
    SCROLLER_Top (LONG)
        Set the current top value of the scroller within the
        proportional range. (V40)

        Applicability is (OM_NEW, OM_SET, OM_UPDATE, OM_GET)

    SCROLLER_Visible (LONG)
        Set the visible portion of the proportional range. (V40)

        (OM_NEW, OM_SET, OM_UPDATE, OM_GET)

    SCROLLER_Total (LONG)
        Set the total range of the scroller. (V40)

        Applicability is (OM_NEW, OM_SET, OM_UPDATE, OM_GET)

    SCROLLER_Orientation
        Define orientation of the scroller.

        Accepted values as defined in <gadgets/scroller.h> are:

            SORIENT_VERT
            SORIENT_HORIZ

        Defines are found in <gadgets/scroller.h> and are synomyms for
        the propgclass FREEVERT and FREEHORIZ. (V40)

        Applicability is (OM_NEW, OM_GET)

    SCROLLER_Arrows (BOOL)
        Enable rendering of optional scroller arrows. (V40)

        Applicability is (OM_NEW, OM_GET)

    SCROLLER_ArrowDelta (WORD) (V41)
        Allows you to change the amount that clicking an arrow causes
        the scroller to move by.

        Defaults to 1.

        Applicability is (OM_NEW, OM_SET, OM_UPDATE, OM_GET)

    SCROLLER_SignalTask (struct Task *)  (V42)
        Signal the specified Task while scroller is active.  This is
        very useful to reduce the load on input.device because you can
        render from some other task (application, or anything else)
        that waits for this signal and then GetAttr() SCROLLER_Top, etc.

        Defaults to NULL (no signaling).

        Applicability is (OM_NEW, OM_SET)

    SCROLLER_SignalTaskBit (ULONG)  (V42)
        Signal with this Bit. See also; SCROLLER_SignalTask.

        Applicability is (OM_NEW, OM_SET)**

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SCROLLER_GetClass()¶

SCROLLER_GetClass -- Gets the pointer to the scroller class.

Synopsis

scroller_class = SCROLLER_GetClass();
D0

Class * SCROLLER_GetClass(VOID);

Function

    Obtains the pointer to the Scroller gadget class for use with
    NewObject().  This function always returns a valid pointer so
    you do not need to check it.  The reason is that if the library
    opens fine, then the pointer returned is already setup.  (Of course
    this implies that if opening the library fails, you shouldn't be
    calling this.)

    Note that this function does not create the class, that is done
    when the class library is opened.

Inputs

    Nothing.

RESULT
    scroller_class - Pointer to the Scroller gadget class.

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