TreeUtil.java

/*! ******************************************************************************
 *
 * Pentaho Data Integration
 *
 * Copyright (C) 2002-2013 by Pentaho : http://www.pentaho.com
 *
 *******************************************************************************
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
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package org.pentaho.di.ui.core.widget;

import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.widgets.Tree;
import org.eclipse.swt.widgets.TreeColumn;
import org.eclipse.swt.widgets.TreeItem;

public class TreeUtil {
  public static final void setOptimalWidthOnColumns( Tree tree ) {
    int nrCols = tree.getColumnCount();
    int[] max = new int[nrCols];
    Image image = new Image( tree.getDisplay(), 10, 10 );
    GC gc = new GC( image );

    for ( int i = 0; i < max.length; i++ ) {
      TreeColumn treeColumn = tree.getColumn( i );
      Point point = gc.textExtent( treeColumn.getText() );
      max[i] = point.x;
    }

    getMaxWidths( tree.getItems(), max, gc );

    gc.dispose();
    image.dispose();

    for ( int i = 0; i < max.length; i++ ) {
      TreeColumn treeColumn = tree.getColumn( i );
      treeColumn.setWidth( max[i] + 30 );
    }
  }

  private static final void getMaxWidths( TreeItem[] items, int[] max, GC gc ) {
    for ( int i = 0; i < items.length; i++ ) {
      for ( int c = 0; c < max.length; c++ ) {
        String string = items[i].getText( c );
        Point point = gc.textExtent( string );
        if ( point.x > max[c] ) {
          max[c] = point.x;
        }
      }
      getMaxWidths( items[i].getItems(), max, gc );
    }
  }

  public static final TreeItem findTreeItem( Tree tree, String[] path ) {
    TreeItem[] items = tree.getItems();
    for ( int i = 0; i < items.length; i++ ) {
      TreeItem treeItem = findTreeItem( items[i], path, 0 );
      if ( treeItem != null ) {
        return treeItem;
      }
    }
    return null;
  }

  private static final TreeItem findTreeItem( TreeItem treeItem, String[] path, int level ) {
    if ( treeItem.getText().equals( path[level] ) ) {
      if ( level == path.length - 1 ) {
        return treeItem;
      }

      TreeItem[] items = treeItem.getItems();
      for ( int i = 0; i < items.length; i++ ) {
        TreeItem found = findTreeItem( items[i], path, level + 1 );
        if ( found != null ) {
          return found;
        }
      }
    }
    return null;
  }
}