Bug 250604 [FieldAssist] API - ContentProposalAdapter needs isShowing() method
Please implement a method ContentProposalAdapter.isShwoing(). The method should return a boolean whether the content assistant proposal popup is open or not.
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/ContentProposalAdapter.java
}
			if (labelProvider == null) {
				return proposal.getLabel() == null ? proposal.getContent()
						: proposal.getLabel();
			}
			return labelProvider.getText(proposal);
		}
		/*
		 * Get the image for the specified proposal. If there is no image
		 * available, return null.
		 */
		private Image getImage(IContentProposal proposal) {
			if (proposal == null || labelProvider == null) {
				return null;
			}
			return labelProvider.getImage(proposal);
		}
		/*
		 * Return an empty array. Used so that something always shows in the
		 * proposal popup, even if no proposal provider was specified.
		 */
		private IContentProposal[] getEmptyProposalArray() {
			return new IContentProposal[0];
		}
		/*
		 * Answer true if the popup is valid, which means the table has been
		 * created and not disposed.
		 */
		private boolean isValid() {
			return proposalTable != null && !proposalTable.isDisposed();