Apple Newton Utilities Guide de l'utilisateur télécharger pdf (Page 126)

100

101

CHAPTER 3

Views

3-42 Using Views

In the latter kind of scrolling, the child views are moved within the parent view by

changing their view bounds. Newly visible views will be opened for the ﬁrst time,

and views which have scrolled completely out-of-view will be closed. The

viewOriginX and viewOriginY slots are not used.

For information about techniques you can use to optimize scrolling so that it

happens as fast as possible, see “Scrolling” (page 3-46), and “Optimizing View

Performance” (page 3-44).

Redirecting Scrolling Messages 3

You can redirect scrolling messages from the base view to another view. Scrolling

and overview messages are sent to the frontmost view; this is the same view that is

returned if you call

GetView('viewFrontMost).

The

viewFrontMost view is found by looking recursively at views that have

both the

vVisible and vApplication bits set in their viewFlags. This

means that you can set the

vApplication bit in a descendant of your base view,

and as long as

vApplication is set in all of the views in the parent chain for that

view, the scrolling messages will go directly to that view. The vApplication bit

is not just for base views, despite what the name might suggest.

If your situation is more complex, where the view that needs to be scrolled cannot

have vApplication set or is not a descendant of your base view, you can have the

base view’s scrolling scripts call the appropriate scripts in the view you wish scrolled.

Working With View Highlighting 3

A highlighted view is identiﬁed visually by being inverted. That is, black and white

are reversed.

To highlight or unhighlight a view, send the view the

Hilite message.

To highlight or unhighlight a single view from a group, send the view the

HiliteUnique message. (The group is defined as all of the child views of one

parent view.)

To highlight a view when the current pen position is within it, send the view the

TrackHilite message. The view is unhighlighted when the pen moves outside

the view bounds. If the view is a button, you can send the view the

TrackButton

message to accomplish the same task.

To get the view containing highlighted data, you can call the global function

HiliteOwner; to get the highlighted text use GetHiliteOffsets.

To highlight some or all of the text in a paragraph, you can use the

SetHilite

method.

1 2 ... 121 122 123 124 125 126 127 128 129 130 131 ... 941 942

Commentaires sur ces manuels

Pas de commentaire

Apple Newton Utilities Guide de l'utilisateur Page 126

Commentaires sur ces manuels

Produits connexes et manuels pour Logiciel Apple Newton Utilities