Flutter 嵌入原生View报错 : Trying to create a platform view of unregistered type

今天，有个童鞋在我的博客 Flutter嵌入原生View，使用原生的WebView 上留言，说遇到了Trying to create a platform view of unregistered type的报错，想问一下有没有遇到过，怎么解决的。在此记录一下，希望能帮到有需要的其他童鞋。

我看了一下，rying to create a platform view of unregistered type这个报错是在PlatformViewsChannel.create() -> PlatformViewsController.createForPlatformViewLayer()中抛出的。

PlatformViewsChannel.java

private void create(@NonNull MethodCall call, @NonNull MethodChannel.Result result) {
	//...省略...
    handler.createForPlatformViewLayer(request);
	//...省略...
}

handler是一个PlatformViewsHandler.java类，我们来看下它的createForPlatformViewLayer方法

public void createForPlatformViewLayer(@NonNull PlatformViewCreationRequest request) {
	//...省略...
	PlatformViewFactory factory = PlatformViewsController.this.registry.getFactory(request.viewType);
	if (factory == null) {
	    throw new IllegalStateException("Trying to create a platform view of unregistered type: " + request.viewType);
	}
	//...省略...
}

可知，抛出Trying to create a platform view of unregistered type异常，是因为获取的PlatformViewFactory为null。
registry是PlatformViewRegistryImpl.java类，我们来看一下

class PlatformViewRegistryImpl implements PlatformViewRegistry {

  PlatformViewRegistryImpl() {
    viewFactories = new HashMap<>();
  }

  // Maps a platform view type id to its factory.
  private final Map<String, PlatformViewFactory> viewFactories;

  @Override
  public boolean registerViewFactory(String viewTypeId, PlatformViewFactory factory) {
    if (viewFactories.containsKey(viewTypeId)) return false;
    viewFactories.put(viewTypeId, factory);
    return true;
  }

  PlatformViewFactory getFactory(String viewTypeId) {
    return viewFactories.get(viewTypeId);
  }
}

可知，viewFactories是一个Map，故是因为没有调用过registerViewFactory方法，导致抛出的这个异常。

所以需要再检查下代码，哪里漏写了。
具体怎么嵌入原生View，可以看我的博客 Flutter嵌入原生View，使用原生的WebView

参考
flutter androidView实现原理