/// <summary>
/// Interface implementation for a callback when the global layout state or
/// the visibility of views within the view tree changes. <see cref="ViewTreeObserver.IOnGlobalLayoutListener"/>
/// </summary>
public void OnGlobalLayout()
{
lastKeyboardHeight = CalculateKeyboardHeight();
var nextState = CalculateKeyboardsNextState(_lastState, lastKeyboardHeight, InputMethodManager.IsAcceptingText);
if (_lastState == nextState)
{
return;
}
_lastState = nextState;
if (_lastState == KeyboardEventTypes.DidHide)
{
_keyboardStateChanged?.Invoke(this, new KeyboardStateEventArgs
{
EventType = KeyboardEventTypes.WillHide,
KeyboardHeight = lastKeyboardHeight
});
}
if (_lastState == KeyboardEventTypes.DidShow)
{
_keyboardStateChanged?.Invoke(this, new KeyboardStateEventArgs
{
EventType = KeyboardEventTypes.WillShow,
KeyboardHeight = lastKeyboardHeight
});
}
_keyboardStateChanged?.Invoke(this, new KeyboardStateEventArgs
{
EventType = nextState,
KeyboardHeight = lastKeyboardHeight
});
}
private void NotifyKeyboardState(KeyboardEventTypes eventType, UIKeyboardEventArgs eventArgs)
{
_lastState = eventType;
if (eventType == KeyboardEventTypes.DidHide)
{
_keyboardHeight = 0;
}
else
{
_keyboardHeight = CalculateKeyboardHeight(eventArgs);
}
KeyboardStateChanged?.Invoke(this, new KeyboardStateEventArgs
{
EventType = eventType,
KeyboardHeight = _keyboardHeight
});
}
private static KeyboardEventTypes CalculateKeyboardsNextState(KeyboardEventTypes currentState, float keyboardHeight, bool isAcceptingText)
{
var isKeyboardVisible = keyboardHeight > 10;
if (!isKeyboardVisible)
{
return(KeyboardEventTypes.DidHide);
}
//NOTE: In case the keyboard is visible(at least partially visible) we continue as follows:
if (isAcceptingText)
{
return(KeyboardEventTypes.DidShow);
}
//NOTE: If the keyboard is not accepting input yet it means it's not reached is final state yet, it is either in a process of hiding or showing it self
if (currentState == KeyboardEventTypes.DidShow)
{
return(KeyboardEventTypes.WillHide);
}
if (currentState == KeyboardEventTypes.DidHide)
{
return(KeyboardEventTypes.WillShow);
}
return(currentState);
}
private void KeyPressed(int keyCode, KeyboardEventTypes type)
{
// Check the repeat-sensitive keys first so that we can
// bail early on repeat events and not check them later
// Shift -> increase volume
if (_shiftKeyCodes.Contains(keyCode))
{
if (type == KeyboardEventTypes.Pressed ||
type == KeyboardEventTypes.Repeated)
{
_velocity = Math.Min(_velocity + 32, 100);
}
return;
}
// Ctrl -> decrease volume
if (_ctrlKeyCodes.Contains(keyCode))
{
if (type == KeyboardEventTypes.Pressed ||
type == KeyboardEventTypes.Repeated)
{
_velocity = Math.Max(_velocity - 32, 1);
}
return;
}
if (type == KeyboardEventTypes.Repeated)
{
return;
}
var qwertyIndex = Array.IndexOf(_qwertyIndeces, keyCode);
// character key -> piano note
if (qwertyIndex >= 0)
{
var keyIndex = _qwertyIndexToKeyIndex[qwertyIndex];
if (type == KeyboardEventTypes.Pressed)
{
_bus.Publish(new KeyPressed(keyIndex, _velocity));
return;
}
_bus.Publish(new KeyReleased(keyIndex));
return;
}
// Space bar -> sustain pedal
if (keyCode == 32)
{
if (type == KeyboardEventTypes.Pressed)
{
_bus.Publish(new SustainPedalPressed());
return;
}
_bus.Publish(new SustainPedalReleased());
return;
}
// Alt -> soft pedal
if (_altKeyCodes.Contains(keyCode))
{
if (type == KeyboardEventTypes.Pressed)
{
_bus.Publish(new SoftPedalPressed());
return;
}
_bus.Publish(new SoftPedalPressed());
return;
}
// Ctrl -> sostenuto pedal
if (_superKeyCodes.Contains(keyCode))
{
if (type == KeyboardEventTypes.Pressed)
{
_bus.Publish(new SostenutoPedalPressed());
return;
}
_bus.Publish(new SostenutoPedalReleased());
return;
}
}
// Temporary API until I nail down keyboard input better. // Based on the GLFW key codes public void PushKeyChange(int keyCode, KeyboardEventTypes type) => OnKeyChange?.Invoke(keyCode, type);