我有一个 SWT 树(通过 JFace TreeViewer),它在列中显示项目,其中一些具有长字符串。字符串的结尾对用户来说是有意义的位,而不是开头,所以当文本被剪辑时,我希望剪辑发生在字符串的开头而不是结尾。例子:
包含以下内容的单元格的默认行为是:“这是一个非常长的字符串,完全超出了树列的边界”:
|This is a very l...|
我想要的地方:
|... the tree column|
编辑:
我使用自定义 PaintItem 侦听器解决了这个问题,如下所述:http: //www.eclipse.org/articles/article.php? file=Article-CustomDrawingTableAndTreeItems/index.html
想出了以下代码(不是很完美,有一些重复和幻数):
tree.addListener(SWT.EraseItem, new Listener()
{
public void handleEvent(Event event)
{
String text = ((TreeItem)event.item).getText(event.index);
Point size = event.gc.textExtent(text);
TreeColumn column = ((Tree)event.widget).getColumn(event.index);
int columnWidth = column.getWidth() - 10; /* magic number alert - the cells have some padding - must be a way of determining this... */
if(size.x > columnWidth)
{
event.detail &= ~SWT.FOREGROUND;
}
}
});
tree.addListener(SWT.PaintItem, new Listener()
{
@Override
public void handleEvent(Event event)
{
String text = ((TreeItem)event.item).getText(event.index);
Point size = event.gc.textExtent(text);
TreeColumn column = ((Tree)event.widget).getColumn(event.index);
int columnWidth = column.getWidth() - 10; /* magic number alert - the cells have some padding - must be a way of determining this... */
if(size.x > columnWidth)
{
drawTextTail(event, text, columnWidth);
}
}
private void drawTextTail(Event event, String text, int columnWidth)
{
String clippedText = "";
int offset = text.length() - 1;
String nextClippedText = text.charAt(offset) + clippedText;
while(fits(nextClippedText, columnWidth, event.gc))
{
clippedText = nextClippedText;
offset--;
nextClippedText = text.charAt(offset) + clippedText;
}
event.gc.drawText("..." + clippedText,
event.x + 5, /* magic number alert - the cells have some padding - must be a way of determining this... */
event.y, false);
}
private boolean fits(String clippedText, int columnWidth, GC gc)
{
Point size = gc.textExtent("..." + clippedText);
return size.x < columnWidth;
}
});