follow method
void
follow(
- ReadOnlyPositionProvider target, {
- double maxSpeed = double.infinity,
- bool horizontalOnly = false,
- bool verticalOnly = false,
- bool snap = false,
Makes the viewfinder follow the given target
.
The target
here can be any read-only PositionProvider. For example, a
PositionComponent is the most common choice of target. Alternatively,
you can use PositionProviderImpl
to construct the target dynamically.
This method adds a FollowBehavior to the viewfinder. If there is another FollowBehavior currently applied to the viewfinder, it will be removed first.
Parameters maxSpeed
, horizontalOnly
and verticalOnly
have the same
meaning as in the FollowBehavior.new constructor.
If snap
is true, then the viewfinder's starting position will be set to
the target's current location. If snap
is false, then the viewfinder
will move from its current position to the target's position at the given
speed.
Implementation
void follow(
ReadOnlyPositionProvider target, {
double maxSpeed = double.infinity,
bool horizontalOnly = false,
bool verticalOnly = false,
bool snap = false,
}) {
stop();
viewfinder.add(
FollowBehavior(
target: target,
owner: viewfinder,
maxSpeed: maxSpeed,
horizontalOnly: horizontalOnly,
verticalOnly: verticalOnly,
),
);
if (snap) {
viewfinder.position = target.position;
}
}