title: Component doesn't re-render when Redux state is changed - React
body: <p>I have <code>RowsCont</code> with <code>renderRows</code></p>
  
  <pre><code>renderRows = () =&gt; {
  
      let result = [];
  
      const {rows} = this.props;
      console.log('RENDER');
      console.log(rows);
      for(let key in rows){
          result.push(&lt;Row={rows[key].id} 
              onHover={this.onHover}
              row={rows[key]}/&gt;);
          }
      return result;
  };
  ....
  render(){&lt;div&gt;{this.renderRows()}&lt;/div&gt;}
  
  ....
  function mapStateToProps(state) {
      console.log('mapState');
      console.log(state.rows.rows);
      return  {
          rows: state.rows.rows,
      }
  }
  </code></pre>
  
  <p>Row Component:</p>
  
  <pre><code>    render(){
  
          return (
              &lt;div&gt;
                  &lt;div&gt;{this.props.row.id}&lt;/div&gt;
                  &lt;div&gt;{this.props.row.value}&lt;/div&gt;
              &lt;/div&gt;
          )
      }
  </code></pre>
  
  <p>Rows is a collection of objects, each like this: <code>{id: 5, value: 'some value'}</code></p>
  
  <p>I have reducer, which changes the value of an object with specific id:</p>
  
  <pre><code>case 'SET_NEW_ROW_VALUE':
          let currentRows = state.rows;
          const changedIndex = currentRows .findIndex((obj) =&gt; obj.id === action.id);
  
          currentRows [changedIndex].value = action.value;
  
          return Object.assign({}, state, {
              rows: currentRows 
  });
  </code></pre>
  
  <p>Everything works, but, if state is changed, the component doesn't re-render.
  I am sure that state is changed, because I see the new state in <code>mapStateToProps</code> with <code>console.log</code>, every time when it is changed, but I don't see <code>console.log</code> from <code>renderRows</code>.</p>
  
  <p>Each row component has and  <code>onHover</code>. If I hover the row, it is re-rendered and I see the new state for the row with the new value.</p>