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

我就是我 2023-10-09 14:16 20阅读 0赞

今天，有个童鞋在我的博客 [Flutter嵌入原生View，使用原生的WebView][Flutter_View_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][Flutter_View_WebView]

> 参考  
> [flutter androidView实现原理][flutter androidView]

[Flutter_View_WebView]: https://blog.csdn.net/EthanCo/article/details/122359045#comments_21726587
[flutter androidView]: https://www.jianshu.com/p/5783cc07fd41