Documentation

Overview

    Package system contains events usually handled at the top-level program level.

    Index

    Constants

    This section is empty.

    Variables

    This section is empty.

    Functions

    This section is empty.

    Types

    type CommandEvent

    type CommandEvent struct {
    	Type CommandType
    	// Cancel suppress the default action of the command.
    	Cancel bool
    }

      CommandEvent is a system event. Unlike most other events, CommandEvent is delivered as a pointer to allow Cancel to suppress it.

      func (*CommandEvent) ImplementsEvent

      func (*CommandEvent) ImplementsEvent()

      type CommandType

      type CommandType uint8

        CommandType is the type of a CommandEvent.

        const (
        	// CommandBack is the command for a back action
        	// such as the Android back button.
        	CommandBack CommandType = iota
        )

        type DestroyEvent

        type DestroyEvent struct {
        	// Err is nil for normal window closures. If a
        	// window is prematurely closed, Err is the cause.
        	Err error
        }

          DestroyEvent is the last event sent through a window event channel.

          func (DestroyEvent) ImplementsEvent

          func (DestroyEvent) ImplementsEvent()

          type FrameEvent

          type FrameEvent struct {
          	// Now is the current animation. Use Now instead of time.Now to
          	// synchronize animation and to avoid the time.Now call overhead.
          	Now time.Time
          	// Metric converts device independent dp and sp to device pixels.
          	Metric unit.Metric
          	// Size is the dimensions of the window.
          	Size image.Point
          	// Insets is the insets to apply.
          	Insets Insets
          	// Frame is the callback to supply the list of
          	// operations to complete the FrameEvent.
          	//
          	// Note that the operation list and the operations themselves
          	// may not be mutated until another FrameEvent is received from
          	// the same event source.
          	// That means that calls to frame.Reset and changes to referenced
          	// data such as ImageOp backing images should happen between
          	// receiving a FrameEvent and calling Frame.
          	//
          	// Example:
          	//
          	//  var w *app.Window
          	//  var frame *op.Ops
          	//  for e := range w.Events() {
          	//      if e, ok := e.(system.FrameEvent); ok {
          	//          // Call frame.Reset and manipulate images for ImageOps
          	//          // here.
          	//          e.Frame(frame)
          	//      }
          	//  }
          	Frame func(frame *op.Ops)
          	// Queue supplies the events for event handlers.
          	Queue event.Queue
          }

            A FrameEvent requests a new frame in the form of a list of operations that describes what to display and how to handle input.

            func (FrameEvent) ImplementsEvent

            func (FrameEvent) ImplementsEvent()

            type Insets

            type Insets struct {
            	Top, Bottom, Left, Right unit.Value
            }

              Insets is the space taken up by system decoration such as translucent system bars and software keyboards.

              type Stage

              type Stage uint8

                Stage of a Window.

                const (
                	// StagePaused is the Stage for inactive Windows.
                	// Inactive Windows don't receive FrameEvents.
                	StagePaused Stage = iota
                	// StateRunning is for active Windows.
                	StageRunning
                )

                func (Stage) String

                func (l Stage) String() string

                type StageEvent

                type StageEvent struct {
                	Stage Stage
                }

                  A StageEvent is generated whenever the stage of a Window changes.

                  func (StageEvent) ImplementsEvent

                  func (StageEvent) ImplementsEvent()

                  Source Files