Fixed performance issue with tables

[Mograsim.git] / net.mograsim.plugin.core / src / net / mograsim / plugin / tables / LazyTableViewer.java

diff --git a/net.mograsim.plugin.core/src/net/mograsim/plugin/tables/LazyTableViewer.java b/net.mograsim.plugin.core/src/net/mograsim/plugin/tables/LazyTableViewer.java
new file mode 100644 (file)
index 0000000..e00742f
--- /dev/null
+++ b/net.mograsim.plugin.core/src/net/mograsim/plugin/tables/LazyTableViewer.java
@@ -0,0 +1,50 @@
+package net.mograsim.plugin.tables;
+
+import org.eclipse.jface.viewers.IContentProvider;
+import org.eclipse.jface.viewers.ILazyContentProvider;
+import org.eclipse.jface.viewers.TableViewer;
+import org.eclipse.swt.SWT;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.swt.widgets.Table;
+
+public class LazyTableViewer extends TableViewer
+{
+
+       public LazyTableViewer(Composite parent, int style)
+       {
+               super(parent, style | SWT.VIRTUAL);
+       }
+
+       public LazyTableViewer(Composite parent)
+       {
+               super(parent);
+       }
+
+       public LazyTableViewer(Table table)
+       {
+               super(table);
+       }
+
+       @Override
+       public void setContentProvider(IContentProvider provider)
+       {
+               if (!(provider instanceof ILazyContentProvider))
+                       throw new IllegalArgumentException("Content provider must be an ILazyContentProvider");
+               super.setContentProvider(provider);
+       }
+
+       public void refreshLazy()
+       {
+               Table t = getTable();
+               ILazyContentProvider provider = (ILazyContentProvider) getContentProvider();
+               doClearAll();
+               int startIndex = t.getTopIndex();
+               int numRows = t.getBounds().height / t.getItemHeight();
+               int endIndex = startIndex + numRows + 5;
+
+               for (int i = startIndex; i < endIndex; i++)
+               {
+                       provider.updateElement(i);
+               }
+       }
+}