documentation/persistence.html

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	<h3>Save settings / Persistence</h3>
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				<p>NatTable settings refer to the changes which the user makes to the grid while using it. 
				The settings which are saved include but are not limited to the following:</p>
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					<li>Hidden columns</li>
					<li>Column order</li>
					<li>Resized columns/rows</li>
					<li>Sorting state</li>
					<li>Column groups state</li>
					<li>Filter row state</li>
				</ol>
				
				<p>The PersistentNatExample is a good place to get started.</p>
				
				<h6>Saving state</h6>
				<p>NatTable saves its state in a <span class="code">java.util.Properties</span> file as key/value pairs. 
				The main method to note is the</p>
				<div class="codeBlock">NatTable.saveState(prefix, properties)</div>
	
				<p>To save state, invoke this method and give it a properties file. This file will be populated with all the sate information. 
				You can now save this file anywhere/anyway you wish. Prefix is any arbitrary string which will be prepended to all the key 
				values in the property file.</p>
	
				<h6>Loading state</h6>	
				<p>The method to note is the</p>
				<div class="codeBlock">NatTable.loadState(String prefix, Properties properties)</div>
				<p>The prefix and properties file are from the save state step.</p>
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			<h5>Saving your custom state</h5>
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				<p>The <span class="code">IPersistable</span> interface is the main interface to note. All the layers which save state, 
				implement this interface. Additionally, you can register your own persistable with any layer using the 
				<span class="code">registerPersistable()</span> on the <span class="code">ILayer</span> interface. Your persistable will 
				be invoked when NatTable state is saved/loaded.</p>
				
				<img align="middle" src="images/persistable.png" border="0" alt="NatTable persistable diagram"/>
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