README.md

change-tracking-react

React extensions for the "change-tracking" library.

installation

npm install @totalsoft/change-tracking-react

info

The library provides three hooks:

• useChangeTrackingState - provides a stateful model with change tracking
• useChangeTrackingLens - provides a stateful model with change tracking using a profunctor lens
• useDirtyInfo - keeps track of modified properties of an external model

useChangeTrackingState hook

React hook for change tracking a model.

It Returns a stateful model, stateful dirty info object, a function that sets the model or property value and a function that resets the change tracking.

Usage example:

import { useChangeTrackingState } from "@totalsoft/change-tracking-react";
import { isPropertyDirty } from "@totalsoft/change-tracking"

const SomeComponent = props => {
  const [person, dirtyInfo, setPerson] = useChangeTrackingState({});
  
  const handleChange = useCallback(
    propPath => event => {
      let newPerson = setInnerProp(person, propPath, event.target.value)
      setPerson(newPerson);
    }, [person]
  );

  return (
    <>
      FirstName dirty: {isPropertyDirty("firstName", dirtyInfo)}
      <TextField
            value={person.firstName}
            onChange={handleChange("firstName")}
      />
      LastName dirty: {isPropertyDirty("lastName", dirtyInfo)}
      <TextField
            value={person.lastName}
            onChange={handleChange("lastName")}
      />
      <ChildComponent details={person.details} onChange={handleChange} />
    </>
  );
};

useChangeTrackingLens hook

Provides a stateful model with change tracking using a profunctor lens.

It returns a stateful model, stateful dirty info object, and a function that resets the change tracking.

Usage example:

import { useChangeTrackingLens, get, set } from "@totalsoft/change-tracking-react";
import { isPropertyDirty } from "@totalsoft/change-tracking"

const onTextBoxChange = onPropertyChange => event => onPropertyChange(event.target.value)

const SomeComponent = props => {
  const [personLens, dirtyInfo, reset] = useChangeTrackingLens({});

  return (
    <>
      FirstName dirty: {isPropertyDirty("firstName", dirtyInfo)}
      <TextField
            value={personLens.firstName |> get}
            onChange={personLens.firstName |> set |> onTextBoxChange}
      />
      LastName dirty: {isPropertyDirty("lastName", dirtyInfo)}
      <TextField
            value={personLens.lastName |> get}
            onChange={personLens.lastName |> set |> onTextBoxChange}
      />
      <ChildComponent detailsLens={personLens.details} />
    </>
  );
};

Note: The reset function clears the dirty info object. If an object is passed as parameter, the model is set to that object, otherwise the current model is kept unchanged. It could also receive an updater function which takes the pending state and compute the next state from it.

Read more about lens operations

useDirtyInfo hook

A react hook for field change tracking.

It returns a stateful dirty info object, a function that sets the property path as dirty and a function that resets the dirty info state.

Usage example:

import { useDirtyInfo } from "@totalsoft/change-tracking-react";
import { isPropertyDirty } from "@totalsoft/change-tracking"

const SomeComponent = props => {
  const [person, setPerson] = useState({});
  const [dirtyInfo, setDirtyInfoPath] = useDirtyInfo();

  const handleChange = useCallback(
    propPath => event => {
      setDirtyInfoPath(propPath);
      setModel({ ...person, [propPath]: event.target.value });
    }, [person]
  );

  return (
    <>
      FirstName dirty: {isPropertyDirty("firstName", dirtyInfo)}
      <TextField
            value={person.firstName}
            onChange={handleChange("firstName")}
      />
      LastName dirty: {isPropertyDirty("lastName", dirtyInfo)}
      <TextField
            value={person.lastName}
            onChange={handleChange("lastName")}
      />
      <ChildComponent details={person.details} onChange={handleChange} />
    </>
  );
};

Note: The reset function clears the dirty info object. If an object is passed as parameter, the model is set to that object, otherwise the current model is kept unchanged.