react-native-sk-datasource-accessor-mixin

##What is it

react-native-sk-datasource-accessor-mixin is a mixin which can easily manipulate ListViewDataSource.

First of all, let's study ListViewDataSource:

ListViewDataSource is composed of several rows, it use three fields to descript these rows:

| Prop | Description | Default | |---|---|---| |sectionIdentities|An array of identifiers for sections, which tell the render order of sections. |None| |rowIdentities|A 2D array of identifiers for rows, which tell the render order of rows. |None| |dataBlob|An map of data for sectionIdentities and rowIdentities, its data structure is <sectionID: <rowID: row>>. |None|

Second, we normally use json data in our application, and I want to convert json to ListViewDataSource's fields.

So, here comes react-native-sk-datasource-accessor-mixin:

1 It offer several methods to manipuldate rows of ListViewDataSource.

for example: 1 appendRows(newRows) 2 deleteRow(row)

2 It accept json array and converts json array into dataBlob and rowIdentities of ListViewDataSource. (Temporarily not handle sectionIdentities).

##How to use it

1. npm install react-native-sk-datasource-accessor-mixin@latest --save

2. Write this in index.ios.js / index.android.js

'use strict';
import React, {
  AppRegistry,
  StyleSheet,
  Text,
  View,
  ListView,
  TouchableHighlight
} from 'react-native';

var DataSourceAccessorMixin = require('react-native-sk-datasource-accessor-mixin');

var test = React.createClass({

  mixins: [DataSourceAccessorMixin], // 1 inherit the mixin

  _idField: 'id', // 2 declare '_idField',  name of field which represents row's ID

  getInitialState(){
    return {
      dataSource: new ListView.DataSource({ // 3 declare a dataSource state first, it will be used in DataSourceAccessorMixin
        rowHasChanged:(row1, row2) => {
          return row1 !== row2;
        }
      }),
    };
  },

  // prepare json data
  componentDidMount(){
   //  var rows = [
   //   {id: 1, text: 'row 1'},
   //   {id: 2, text: 'row 2'},
   //   {id: 3, text: 'row 3'},
   //   {id: 4, text: 'row 4'},
   //   {id: 5, text: 'row 5'},
   //   {id: 6, text: 'row 6'},
   //   {id: 7, text: 'row 7'},
   //   {id: 8, text: 'row 8'},
   //   {id: 9, text: 'row 9'},
   //  ];
    var rows = [];
    for(var i = 0; i < 10; i++){
      rows.push({id: i, text: 'row ' + i},)
    }
    this.setRows(rows);
  },

  onPressRow(row) {
    console.log(row+' pressed');
    this.currRow = row;
  },

  renderRow(row) {
    return (
      <TouchableHighlight
        style={styles.row}
        underlayColor='#c8c7cc'
        onPress={() => this.onPressRow(row)}
      >
        <Text>{row.text}</Text>
      </TouchableHighlight>
    );
  },

 onAppendRow(){
   var n = this.rowCount();
   this.appendRow({id: n, text: 'row ' + n}) // append a row
 },

 onDeleteRow(){
   if(!this.currRow){
     console.log('no selected row');
     return;
   }
   this.deleteRow(this.currRow) // delete a row
 },

  render() {
    return (
      <View style={styles.container}>
        <ListView
         dataSource={this.state.dataSource} // 4 use the dataSource state in listview
         renderRow={this.renderRow}
       />
       <View style={styles.btnBox}>
         <TouchableHighlight
           style={styles.btn}
           underlayColor='#c8c7cc'
           onPress={this.onAppendRow}
         >
           <Text>append row</Text>
         </TouchableHighlight>
         <TouchableHighlight
           style={styles.btn}
           underlayColor='#c8c7cc'
           onPress={this.onDeleteRow}
         >
           <Text>delete row</Text>
         </TouchableHighlight>
       </View>
      </View>
    );
  }
});

var styles = {
  container: {
    flex: 1,
    backgroundColor: '#FFF',
  },
  row: {
    padding: 10,
    height: 44,
    backgroundColor: 'yellow',
    borderBottomColor: 'grey',
    borderBottomWidth: 2,
  },
  btnBox: {
    flexDirection: 'row',
    justifyContent: 'space-around',
    height: 44,
  },
  btn: {
    width: 90,
    height: 40,
    backgroundColor: 'grey',
    justifyContent: 'center',
    alignItems: 'center',
    borderRadius: 5,
  }
};

AppRegistry.registerComponent('test', () => test);

##Methods

| Method | Description | Params | |---|---|---| |idField()|Get name of field which represents row's ID. |None| |isEmpty()|Whether there is no rows. |None| |rowCount()|Count of rows. |None| |rows()|Get rows. |None| |rowIds()|Get row's IDs. |None| |setRows(newRows)|Set rows. |None| |appendRows(newRows)|Insert multiple rows at the end. |None| |prependRows(newRows)|Insert multiple rows in the head. |None| |appendRow(newRow)|Insert one row at the end. |None| |prependRow(newRow)|Insert one row in the head. |None| |deleteRow(row)|Delete row by ID. |None|