BlogJava-Hexise's Blog-随笔分类-Eclipse Plugin

GEF编辑器的区域及滚动条

Hexise — Fri, 29 Dec 2006 05:16:00 GMT

GEF编辑器是构架在Draw2D的FigureCanvas上的,而FigureCanvas是swt中Canvas的子类.

当得到FigureCanvas之后,就可以得到GEF编辑器的区域和GEF编辑器内部画布的大小:

编辑器区域大小:FigureCanvas.getBounds();
这是运用了FigureCanvas是Canvas子类的特点,调用SWT的Canvas的getBounds()方法,即调用Control的getBounds()方法.

画布大小:FigureCanvas.getContents.getBounds();
这是运用了IFigure的getBounds()方法, 这两个区域矩形不可混淆.

若要触发GEF编辑器的滚动条操作,仅需调用FigureCanvas的scrollToX(int hOffset)和scrollToY(int vOffset)即可.

获取FigureCanvas的方法也比较简单.通过EditPart.getViewer()获得EditPartViewer,一般情况下EditPartViewer的Control就是FigureCanvas.

列出代码如下:

FigureCanvas canvas = (FigureCanvas)EditPart.getViewer().getControl();
canvas.scrollToX( 500 );
canvas.scrollToY( 600 );
System.out.println(canvas.getBounds());
System.out.println(canvas.getContents().getBounds());

Hexise 2006-12-29 13:16 发表评论

eclipse创建Image方法

Hexise — Fri, 29 Dec 2006 04:43:00 GMT

通过图像的相对路径创建org.eclipse.swt.graphics.Image,我通常使用下面两种途径:

1.使用Image(Device device, InputStream stream)构造函数,示例代码如下, path为图像相对路径:

private Image getImage(String path){
return new Image(Display.getCurrent(), getClass().getResourceAsStream(path));
}

2.使用ImageDescriptor的createImage()方法,示例代码如下,path为图像相对路径:

private Image getImage(String path){
  URL url = null;
  try{
   url = new URL(Activator.getDefault().getDescriptor().getInstallURL(), path);
  }catch(MalformedURLException e){
   e.printStackTrace();
  }
  ImageDescriptor imageDescriptor = ImageDescriptor.createFromURL(url);
  return imageDescriptor.createImage();
}

或者:

private Image getImage(String path){
ImageDescriptor desc = AbstractUIPlugin.imageDescriptorFromPlugin(ID, path);
return desc.createImage();
}

Hexise 2006-12-29 12:43 发表评论

eclipse中的相对坐标和绝对坐标

Hexise — Fri, 29 Dec 2006 04:26:00 GMT

转换成相对坐标,要运用translateToRelative(Point point)方法.

例如,在Eclipse Editor视图中加入Figure,需要计算出相对于HostFigure的坐标,才能正确将figure放在鼠标点击的位置.可以如下这样做:

在getCreateCommand(CreateRequest request)方法中,加入如下语句:

Point location = request.getLocation().getCopy();
getHostFigure().translateToRelative(location);

如此获得的location就是相对于HostFigure的坐标.

能够获得当前光标绝对坐标的方法是:

Display.getDefault().getCursorLocation()

Hexise 2006-12-29 12:26 发表评论

Eclipse插件如何刷新资源管理器?

Hexise — Fri, 29 Dec 2006 04:19:00 GMT

最近项目中出现了一个bug,提示是Resource can not sync with file system.是文件系统不同步的问题,需要手动刷新一下资源管理器.

刷新资源管理器调用方法:

RefreshLocal

public void refreshLocal(int depth, IProgressMonitor monitor)
throws CoreException

Refreshes the resource hierarchy from this resource and its children (to the specified depth) relative to the local file system. Creations, deletions, and changes detected in the local file system will be reflected in the workspace's resource tree. This resource need not exist or be local.
This method may discover changes to resources; any such changes will be reported in a subsequent resource change event.

If a new file or directory is discovered in the local file system at or below the location of this resource, any parent folders required to contain the new resource in the workspace will also be created automatically as required.

This method is long-running; progress and cancellation are provided by the given progress monitor.

Parameters:
depth - valid values are DEPTH_ZERO, DEPTH_ONE, or DEPTH_INFINITE
monitor - a progress monitor, or null if progress reporting is not desired
Throws:
CoreException - if this method fails. Reasons include:
Resource changes are disallowed during certain types of resource change event notification. See IResourceChangeEvent for more details.
OperationCanceledException - if the operation is canceled. Cancelation can occur even if no progress monitor is provided.
See Also:
DEPTH_ZERO, DEPTH_ONE, DEPTH_INFINITE, IResourceRuleFactory.refreshRule(IResource)

该方法位于org.eclipse.core.resources.IResource

我的调用方法是:

ResourcesPlugin.getWorkspace().getRoot().refreshLocal(IResource.DEPTH_INFINITE, monitor);

Hexise 2006-12-29 12:19 发表评论

属于自己的Property View

Hexise — Fri, 29 Dec 2006 03:14:00 GMT

可以扩展属于自己的property view吗?换句话说,能否再扩展出一个property view出来,并对它进行定制?

答案是可以的.

如果你所写的Property View类继承自PropertySheet,那么它就是扩展出的新property view. 你同样可以对其进行定制,不会干扰到原有的property的正常显示.

例如,你可以让你的property view 不监听某个XYZView中的事件,只需要覆盖掉isImportant方法就可以了.

import org.eclipse.ui.IWorkbenchPart;
import org.eclipse.ui.views.properties.PropertySheet;

public class PropertyView extends PropertySheet {

   protected boolean isImportant(IWorkbenchPart part) {
         return part != this && ! (part instanceof XYZView);
    }
}

Hexise 2006-12-29 11:14 发表评论