Support Keyboard

[licanhua]

Fix #2469.

Add supportKeyboard, and this function can add to any Controls. The whole implementation is simplified three small tasks:

1. RootView dispatches topKeyDown/topKeyUp when PreviewKeyDown/ PreviewKeyUp happened on RootView. Target would be the OriginalSource id.
2. If keyDownEvents or keyUpEvents is set, mark that control’s handled to true based on the condition.
3. In GetExportedCustomBubblingEventTypeConstants, add keyDown and keyUp.

Example code for customer to use it:

const handledNativeKeyboardEvents: IHandledKeyboardEvent[] = [
  { key: 'a', handledEventPhase:  HandledEventPhase.Capturing },
  { key: 'b' },
  { key: 'c', handledEventPhase:  HandledEventPhase.Bubbling },
  { key: 'Tab', handledEventPhase: HandledEventPhase.Capturing }
];

const ViewWindows = supportKeyboard(View)
        <ViewWindows
          style={styles.keyComponentRoot}
          onKeyDownCapture={this._onKeyDownCapture}
          onKeyUpCapture={this._onKeyUpCapture}
          onKeyUp={this._onKeyUp}
          onKeyDown={this._onKeyDown}
          keyDownEvents={handledNativeKeyboardEvents} 
          keyUpEvents={handledNativeKeyboardEvents}
        >

Note:

1. user never receive key='a' events, and it's always be 'A'.
2. key 'a' and 'A' are the same meaning in HandledKeyboardEvent
3. exact match is done for HandledKeyboardEvent. that means 'a', 'a'+shift, 'a'+alt' and 'a'+shift+alt are not the same.

Microsoft Reviewers: Open in CodeFlow

[ahimberg]

🕐

[kmelmon]

[ghost]

Hello @licanhua!

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[randy-flynn]