This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
The attached screenshot consists of 2 JPanels. Each has 2 JLists. I want to allow drag and drop only inside one JPanel. For instance drops from TopPanel to ButtomPanel or complete outside to desktop or something else should NOT be allowed. My solution already works panel specific, but drops outside are still possible. How can I deactivate that? Here is the standalone example code: