Add Support for onTapDown

[tilucasoli]

Description:

Mix supports $on.press for styling Widgets, but the style is applied only after the press action is completed (onTapUp). Developers have expressed the need for styling during the onTapDown event.

User Stories:

1. As a developer using Mix,
   I want to style widgets specifically during the onTapDown event,
   so that I can provide immediate visual feedback, such as color changes or scaling, when a button is pressed.

Acceptance Criteria:

• Add support for the onTapDown event in widget and expose it in the styling API.
• The widget should only rebuild if it is listening to the state.
• Ensure that onTapDown styles are applied immediately when the user presses the widget and reset when the press is released or canceled.
• Include unit and integration tests to validate the functionality of onTapDown event styling.
• Write documentation explaining how to use the onTapDown styling feature.
  • Add examples demonstrating use cases such as changing widget color or scaling on press.

Resources:

• Support for onDoubleTap and other properties on Pressable #452 (comment)

Example of API

$on.press.event((e) {
  switch (e) {
    case MixPressEvent.onTapDown:
      return Style(
        $box.color.red(),
      );
    case MixPressEvent.onTapUp:
      return Style();
  }
});

[lvsecoto]

If we have a StyledMaterial，then we have ripple effect

StyledMaterial(
   child: InkWell(
     onTap() {
     },
   ),
);

[tilucasoli]

If we have a StyledMaterial，then we have ripple effect

StyledMaterial(
   child: InkWell(
     onTap() {
     },
   ),
);

@lvsecoto, We will create a specific issue to track the solution for InkWell. While support for onTapDown is related, it is not the same issue.

[tilucasoli]

An alternative is to create a utility for tap that is triggered whenever any onTap method is called. The API would look like:

$on.tap((e) {
  switch (e) {
    case OnTapEvent.onTapDown:
      return Style(
        $box.color.red(),
      );
    case OnTapEvent.onTapUp:
      return Style();
  }
});

• The enum OnTapEvent should contains a case for every onTap method.
• The tap utility should receive a as parameter Function(OnTapEvent)

[tilucasoli]

The press state must remain active while the button is held; it shouldn't replace the state for a longPress.