Subtle places in React.js
React is, of course, a breakthrough technology that simplifies the creation of complex interfaces, but, like any abstraction, it has its own small problems and features. In my practice, I ran into four not very obvious things. It’s difficult to call it buggy - it’s just a feature of the library. About them today and talk.
There is such a delicate moment not described in the documentation. Prior to version 0.14, the call to
... and every call to
')
In 0.14, work with
Alternatively, always create a new item:
If you use
The first moment - in 0.14 the algorithm was changed, deciding whether to redraw the root element or not
There is such a delicate moment not described in the documentation. Prior to version 0.14, the call to
React.render() always redrawn what was passed to it. It was possible to save a link to the root element ... const element = <MyComponent />; ... and every call to
React.render(element) redraws the application.')
In 0.14, work with
props improved, and the algorithm became “smarter”. Now, if the same object arrives, they check props and state for the already drawn one. In other words, having saved a link to an element, you need to either change its state , or make a copy, or do setProps() before rendering. import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { render() { const date = Date.now(); return <div>The time is {date}</div>; } } const app = document.getElementById("app"); const element = <MyComponent />; const ref = ReactDOM.render(element, app); ReactDOM.render(element, app); // render() ref.forceUpdate(); // Alternatively, always create a new item:
const app = document.getElementById("app"); const ref = ReactDOM.render(<MyComponent />, app); ReactDOM.render(<MyComponent />, app); The second moment - if you are working with controls, the call to ReactDOM.render () should go synchronously with the control events.
If you use
, . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , !, . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , ! , . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , !, . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , ! , . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , !, . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , ! , . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , !, . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , !, . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , !
, . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , !, . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , ! , . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , !, . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , ! , . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , !, . ., ReactDOM.render() .
, , , - - .
import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { bizLogic1(e.currentTarget.value); bizLogic2(e.currentTarget.value); bizLogic3(e.currentTarget.value); } render() { return ( <select size="3" value={this.props.selectedId} onChange={this.handleChange.bind(this)}> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> ); } }
... FLUX- , , , selectedId , - bizLogic1-3 , . , bizLogic* , , , .
let selectedId = 1; const app = document.getElementById("app"); function bizLogic1(newValue) { selectedId = newValue; renderAfterwards(); } function bizLogic2(newValue) { //... renderAfterwards(); } function bizLogic3(newValue) { //... renderAfterwards(); } let renderRequested = false; function renderAfterwards() { if (!renderRequested) { // , , // render() <select> window.setTimeout(() => { ReactDOM.render(<MyComponent selectedId={selectedId} />, app, () => { renderRequested = false; }); }, 0); } } //initial render ReactDOM.render(<MyComponent selectedId={selectedId} />, app);
, , select' — , 'onchange' , bizLogic1-3 , props . , . React ( ) <select'> . ReactDOM.render() , , , , .
, UI ReactDOM.render() .
Dispatcher FLUX:
class MyComponent extends React.Component { handleChange(e) { dispatch({action: "ACTION_OPTION_SELECT", value: e.currentTarget.value}); } ... } function dispatch(action) { if (action.action === "ACTION_OPTION_SELECT") { bizLogic1(action); bizLogic2(action); bizLogic3(action); } ReactDOM.render(<MyComponent selectedId={selectedId} />, app); }
TestUtils.Simulate.change
, , React TestUtils , , . , ReactUtils , . , target currentTarget :
describe("MyInput", function() { it("refuses to accept DEF", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); var fakeInput = {value: "DEF"}; TestUtils.Simulate.change(rootNode, {currentTarget: fakeInput}); // , TestUtils currentTarget expect($(rootNode).val()).toEqual("abc"); // , .. handleChange <input> currentTarget }); });
( , ) ,
2 — React , . - , , .
:
import {$} from "commonjs-zepto"; import React from "react"; import ReactDOM from "react-dom"; class MyComponent extends React.Component { handleChange(e) { let value = e.currentTarget.value; if (!value.match(/[0-9]/)) bizLogic(value); } render() { return <input type="text" value={this.props.value} onChange={this.handleChange.bind(this)} />; } } const app = document.getElementById("app"); describe("MyInput", function() { it("refuses to accept digits", function() { var ref = ReactDOM.render(<MyComponent value="abc" />, app); var rootNode = ReactDOM.findDOMNode(ref); $(rootNode).val("abc1"); // TestUtils.Simulate.change(rootNode); //handleChange <input value="abc1"> // React "abc" expect($(rootNode).val()).toEqual("abc"); // , , .. value React' // , bizLogic , , "abc" }); });
, , !Source: https://habr.com/ru/post/273995/
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