Surveying signal component

title

Please understand first when reading this section computed and watch chapter.

about

Calculating signal component is will computedObject package into a signal component, should computedObject when the state data changes, the re -rendering of the signal component is automatically triggered. The monitoring signal component is watchObject package into a signal component, should watchObject when the state data changes, the re -rendering of the signal component is automatically triggered.

The method function signature is as follows:

interface SignalComponentType<State extends Dict>{
    <Value=any, Scope=any >(render:SignalComponentRender,getter:AsyncComputedGetter<Value,Scope>):React.ReactNode
    <Value=any, Scope=any >(render:SignalComponentRender,getter:ComputedGetter<Value,Scope>):React.ReactNode
    <Value=any, Scope=any >(render:SignalComponentRender,builder: ObserverDescriptorBuilder<string,Value,Scope>):React.ReactNode;
}
```## Surveying signal component

How to calculate the signal component is right `computed` the package, the monitoring signal component can be realized `watch` packaging.

```ts  {3-5,7-9}
$<any>( 
    ({value})=>{
      return <div>{value}</div>
    },
    watch(({path,value},watchObj)=>{
      return xxxx
    })
)

The following is an example of a monitoring signal component:

• In the previous example, we use watch come to create a monitoring signal dynamically.
• In the state validate when changing, we calculate the effectiveness of the entire state, and then write the results of the effectiveness validate in this way, the re -rendering of the monitoring signal component is triggered.