47 lines
933 B
Go
47 lines
933 B
Go
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package ui
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type EventFn func(Context) bool
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type EventStateFn func(Context, interface{})
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func NewEvents() *Events {
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return &Events{events: map[uint]EventStateFn{}}
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}
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type Events struct {
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nextID uint
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events map[uint]EventStateFn
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}
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type EventHandler interface {
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AddHandler(EventFn) uint
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AddHandlerState(EventStateFn) uint
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RemoveHandler(uint)
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}
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func (e *Events) Notify(ctx Context, state interface{}) bool {
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if e.events == nil {
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return false
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}
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for _, handler := range e.events {
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handler(ctx, state)
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}
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return len(e.events) > 0
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}
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func (e *Events) AddHandler(handler EventFn) uint {
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return e.AddHandlerState(func(ctx Context, _ interface{}) { handler(ctx) })
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}
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func (e *Events) AddHandlerState(handler EventStateFn) uint {
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if e.events == nil {
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e.events = map[uint]EventStateFn{}
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}
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id := e.nextID
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e.nextID++
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e.events[id] = handler
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return id
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}
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func (e *Events) RemoveHandler(id uint) { delete(e.events, id) }
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