Draw and interact with SVG in Flutter

问题

We are developing an application which displays a human body, based on a SVG input. This human body is divided in several regions, think of a head, left-arm, right-arm, belly etc.

We want to highlight a region of the image when the user clicks on for example one arm. What is the best way to achieve such a thing in Flutter?

We tried to use Flare for Flutter, but this librart does not provide direct interaction with the human body being displayed.

Is there an easier way to:

• Render the body based on a SVG (artwork might change in future developnent);
• Detect click, e.g. GestureDetector;
• Find pressed region based on the coordinates of the click;

Note that simple boxes will not work since parts of the image overlap. You can see the effect we want to achieve, I clicked on one arm here. Drawing some clickable box around it, will not work well.

Thanks in advance.

回答1:

I made it working by using the built_path library, which precompiles SVG paths into Path objects. We then wrapped it into a ClipPath Widget as follows:

return GestureDetector(
    onTap: () => _bodyPartTapped(part),
    child: ClipPath(
        child: Stack(children: <Widget>[
          Container(
              color: pressedBodyPart == part
                  ? Colors.blue
                  : Colors.transparent),
          CustomPaint(painter: PathPainter(path))
        ]),
        clipper: PathClipper(path)));

It will color a body part blue if it's pressed, which is working perfectly fine.

I have created a full example which can be found here: https://github.com/gi097/flutter_clickable_regions

来源：https://stackoverflow.com/questions/57489968/draw-and-interact-with-svg-in-flutter