| The TextHitInfo class represents a character position in a
text model, and a bias, or "side," of the character. Biases are
either leading (the left edge, for a left-to-right character)
or trailing (the right edge, for a left-to-right character).
Instances of TextHitInfo are used to specify caret and
insertion positions within text.
For example, consider the text "abc". TextHitInfo.trailing(1)
corresponds to the right side of the 'b' in the text.
TextHitInfo is used primarily by
TextLayout and
clients of TextLayout. Clients of TextLayout
query TextHitInfo instances for an insertion offset, where
new text is inserted into the text model. The insertion offset is equal
to the character position in the TextHitInfo if the bias
is leading, and one character after if the bias is trailing. The
insertion offset for TextHitInfo.trailing(1) is 2.
Sometimes it is convenient to construct a TextHitInfo with
the same insertion offset as an existing one, but on the opposite
character. The getOtherHit method constructs a new
TextHitInfo with the same insertion offset as an existing
one, with a hit on the character on the other side of the insertion offset.
Calling getOtherHit on trailing(1) would return leading(2).
In general, getOtherHit for trailing(n) returns
leading(n+1) and getOtherHit for leading(n)
returns trailing(n-1).
Example:
Converting a graphical point to an insertion point within a text
model
TextLayout layout = ...;
Point2D.Float hitPoint = ...;
TextHitInfo hitInfo = layout.hitTestChar(hitPoint.x, hitPoint.y);
int insPoint = hitInfo.getInsertionIndex();
// insPoint is relative to layout; may need to adjust for use
// in a text model
See Also: TextLayout |
