Android React Native組件的生命周期

和Android一樣，React的組件也有對應的生命周期。Android React Native組件的生命周期可以總的概括為下面這一張圖。

可以把組件生命周期大致分為三個階段：

生命周期回調函數總共有10個。

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最後的輸出如下，我們在componentDidMount中調用了loadDataToSetState函數，該函數中通過了setState函數對state進行了設置，這時候就會回調shouldComponentUpdate，如果返回true，則會繼續調用componentWillUpdate，render,conponentDidUpdate，之後按返回鍵退出應用，則會進行銷毀操作，回調componentWillUnmount

getDefaultProps
getInitialState
componentWillmount
render
componentDidMount
loadDataToSetState
shouldComponentUpdate
componentWillUpdate
render
conponentDidUpdate
componentWillUnmount

var Name =React.createClass({
    getDefaultProps:function(){
        console.log("Name getDefaultProps");
        return null;
    },
    getInitialState:function(){
        console.log("Name getInitialState");
        return null;
    },
    componentWillMount:function(){
        console.log("Name componentWillmount");
    },
    render:function(){
        console.log("Name render");
        return (
            
                Hello,{this.props.name? this.props.name:"None!"}
            
        );
    },
    componentDidMount:function(){
        console.log("Name componentDidMount");
    },
    componentWillReceiveProps:function(nextProps){
        console.log("Name componentWillReceiveProps");
        console.log(nextProps);
    },
    shouldComponentUpdate:function(nextProps,nextState){
        console.log("Name shouldComponentUpdate");
        return true;
    },
    componentWillUpdate:function(nextProps,nextState){
        console.log("Name componentWillUpdate");
    },
    componentDidUpdate:function(prevProps,prevState){
        console.log("Name conponentDidUpdate");
    },
    componentWillUnmount:function(){
        console.log("Name componentWillUnmount");
    },
});

return {name:"a"};

this.setState({
            name:"lizhangqu"
        });

var Parent = React.createClass({

    render:function(){
        return (
            
                
            

        );
    },

    getInitialState:function(){

        return {name:"a"};
    },

    componentDidMount:function(){

        this.setState({
            name:"lizhangqu"
        });
    },
});

var AwesomeProject = React.createClass({
  render: function() {
    return (
        
    );
  }
});

Name getDefaultProps
Name getInitialState
Name componentWillmount
Name render
Name componentDidMount
Name componentWillReceiveProps
Object {name: "lizhangqu"}
Name shouldComponentUpdate
Name componentWillUpdate
Name render
Name conponentDidUpdate
Name componentWillUnmount