enum Gdk::ScrollUnit

Overview

Specifies the unit of scroll deltas.

When you get %GDK_SCROLL_UNIT_WHEEL, a delta of 1.0 means 1 wheel detent click in the south direction, 2.0 means 2 wheel detent clicks in the south direction... This is the same logic for negative values but in the north direction.

If you get %GDK_SCROLL_UNIT_SURFACE, are managing a scrollable view and get a value of 123, you have to scroll 123 surface logical pixels right if it's @delta_x or down if it's @delta_y. This is the same logic for negative values but you have to scroll left instead of right if it's @delta_x and up instead of down if it's @delta_y.

1 surface logical pixel is equal to 1 real screen pixel multiplied by the final scale factor of your graphical interface (the product of the desktop scale factor and eventually a custom scale factor in your app).

Defined in:

lib/gi-crystal/src/auto/gdk-4.0/gdk.cr

Enum Members

Wheel = 0_u32

The delta is in number of wheel clicks.

Surface = 1_u32

The delta is in surface pixels to scroll directly on screen.

Class Method Summary

• .g_type : UInt64

  Returns the type id (GType) registered in GLib type system.

Instance Method Summary

• #surface?
• #wheel?

Class Method Detail

Instance Method Detail