Lotus Notes 8 プラグインでグラフィックコンテキストを利用する

<?xml version="1.0" encoding="UTF-8"?>
<?eclipse version="3.2"?>
<plugin>

   <extension
         point="org.eclipse.ui.views">
      <category
            name="Eyes Category"
            id="Eyes">
      </category>
      <view
            name="Eyes"
            allowMultiple="true"
            icon="icons/sample.gif"
            category="Eyes"
            class="eyes.views.EyesView"
            id="eyes.views.EyesView">
      </view>
   </extension>
   
   <extension
         point="com.ibm.rcp.ui.shelfViews">
      <shelfView
            id="eyes.views.EyesView"
            region="TOP"
            showTitle="true"
            view="eyes.views.EyesView"/>
   </extension>
   
   <extension
         point="org.eclipse.ui.perspectiveExtensions">
   :
   :

package eyes.views;


import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.part.ViewPart;


public class EyesView extends ViewPart {
	//. Canvasオブジェクトと、GCオブジェクトを定義①
	private Canvas canvas = null;
	private GC gc = null;

	public EyesView() {
	}

	public void createPartControl(Composite parent) {
		//. 画面いっぱいに拡大②
		parent.setLayout( new FillLayout() );

		//. Canvas の取得③
		canvas = new Canvas( parent, SWT.NONE );
		canvas.setLayout( new FillLayout() );
		canvas.setBackground( new Color( canvas.getDisplay()
				, new RGB( 0, 0, 0 ) ) );
		
		//. GC の取得④
		gc = new GC( canvas );
	}

	public void setFocus() {
	}
}

package eyes.views;


import org.eclipse.swt.SWT;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.events.MouseMoveListener;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.part.ViewPart;


public class EyesView extends ViewPart {
	//. Canvasオブジェクトと、GCオブジェクトを定義①
	private Canvas canvas = null;
	private GC gc = null;
	
	//. 直前のマウス座標を記憶しておくための変数⑤
	private int mx = -1, my = -1;

	public EyesView() {
	}

	public void createPartControl(Composite parent) {
		//. 画面いっぱいに拡大②
		parent.setLayout( new FillLayout() );

		//. Canvas の取得③
		canvas = new Canvas( parent, SWT.NONE );
		canvas.setLayout( new FillLayout() );
		canvas.setBackground( new Color( canvas.getDisplay()
				, new RGB( 0, 0, 0 ) ) );
		
		//. GC の取得④
		gc = new GC( canvas );
		

		//. Canvas 上のマウス移動イベントをハンドリング⑥
		canvas.addMouseMoveListener( new MouseMoveListener(){
			public void mouseMove(MouseEvent e){
				//. マウス座標を保存
				mx = e.x;
				my = e.y;
				
				//. Canvas を再描画
				updateCanvas();
			}
		});
	}

	public void setFocus() {
	}
	
	
	
	//. GC を利用して Canvas を再描画する⑦
	private void updateCanvas(){
		//. マウス位置の方を向く両目玉を描画
		if( gc != null ){
		    int lx, ly, rx, ry;

		    //. キャンバスのサイズを取得
		    int sw = canvas.getSize().x;
		    int sh = canvas.getSize().y;

		    //. 計算用変数
		    int a = ( int )( sw / 2 * 0.35 );
		    int b = ( int )( sh * 0.35 );

		    //. 両目の白目部分を描画
		    gc.setForeground( new Color( null, 255, 255, 255 ) );
		    gc.setBackground( new Color( null, 255, 255, 255 ) );
		    gc.fillOval( ( int )( sw / 2 * 0.05 ), ( int )( sh * 0.05 ),
		        ( int )( sw / 2 * 0.9 ), ( int )( sh * 0.9 ) );
		    gc.fillOval( ( int )( sw / 2 * 1.05 ), ( int )( sh * 0.05 ),
		        ( int )( sw / 2 * 0.9 ), ( int )( sh * 0.9 ) );

			//. （以下略、詳細はサンプルファイルを参照）
		}
	}

}