29 lines
632 B
Go
29 lines
632 B
Go
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package uix
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import "errors"
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// LinkStart initializes the Link tool.
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func (w *Canvas) LinkStart() {
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w.Tool = LinkTool
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w.linkFirst = nil
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}
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// LinkAdd adds an actor to be linked in the Link tool.
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func (w *Canvas) LinkAdd(a *Actor) error {
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if w.linkFirst == nil {
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// First click, hold onto this actor.
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w.linkFirst = a
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} else {
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// Second click, call the OnLinkActors handler with the two actors.
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if w.OnLinkActors != nil {
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w.OnLinkActors(w.linkFirst.Actor, a.Actor)
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} else {
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return errors.New("Canvas.LinkAdd: no OnLinkActors handler is ready")
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}
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// Reset the link state.
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w.linkFirst = nil
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}
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return nil
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}
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