title: understanding "Layout run failure" error logging
body: <p>I am doing some charting work and got a single line message "Layout run failure" when nothing was being created on the chart. Looking into this I found that I have to add some additional script files to generate the log files as covered <a href="http://dev.sencha.com/deploy/ext-4.1.0-gpl/release-notes.html" rel="noreferrer">here</a>:</p>
  
  <blockquote>
    <p>Layout Failures</p>
    
    <p>As result of the design for the layout engine in 4.1, it is possible
    for improper configuration (or a bug) to cause a layout run to fail to
    complete all of its calculations. When this occurs, the layout simply
    stops and the partial results that have been flushed to the DOM are
    all that is visible. In some cases, the layout may be 99% complete and
    the failure may go undetected or appear as a minor visual anomaly. In
    other cases, the layout may fail early and leave the UI in a clearly
    broken state (much like a JS error during layout would do in previous
    versions).</p>
    
    <p>Diagnostics</p>
    
    <p>The first step if you suspect you are seeing a layout failure is to
    enable the layout diagnostics. This is done by replacing the normal
    "ext-all.js" file with "ext-all-dev.js" and adding a couple additional
    scripts.</p>
  </blockquote>
  
  <p>I added the required scripts:</p>
  
  <pre><code>&lt;script type="text/javascript" src="extjs/src/diag/layout/Context.js"&gt;&lt;/script&gt;
  &lt;script type="text/javascript" src="extjs/src/diag/layout/ContextItem.js"&gt;&lt;/script&gt;
  </code></pre>
  
  <p>And now I get diagnostic data that I can't make any sense of - it doesn't seem to diagnose an error:</p>
  
  <pre><code>++printer&lt;autocontainer&gt; - size: configured/shrinkWrap
      --statprint-1472&lt;autocontainer&gt; - size: configured/configured
          triggeredBy: count=1
              statprint-1472.containerChildrenDone:dom () dirty: false, setBy: ?
          --chart-1473&lt;draw&gt; - size: shrinkWrap/shrinkWrap
              triggeredBy: count=1
                  chart-1473.containerChildrenDone:dom (true) dirty: false, setBy: ?
      ++panel-1474&lt;dock&gt; - boxParent: printer - size: natural/configured
      ++panel-1474&lt;autocontainer&gt; - boxParent: printer - size: natural/configured
      ++statprint-1472&lt;dock&gt; - size: configured/configured
          ++statprint-1472_header&lt;body&gt; [isBoxParent] - size: calculated/shrinkWrap
          ++statprint-1472_header&lt;hbox&gt; [isBoxParent] - size: calculated/shrinkWrap
              ++statprint-1472_header_hd&lt;autocomponent&gt; [isBoxParent] - size: calculated/shrinkWrap
              ++tool-1475&lt;autocomponent&gt; [isBoxParent] - size: configured/configured
  </code></pre>
  
  <p>Does any one know where the diagnostic information is explained?</p>