NetBeans JFrame GUI运行时所有JLabel都显示为灰色

I'm having a problem with the GUI of a java project. I construct the GUI using the Netbeans GUI-builder. In the construction field, more specifically, Netbeans all the JLabels appear deep black but when I run the file (shift-F6) all the JLabels appear grayed out. Here are some screens to clarify the problem:I'm having a problem with the GUI of a java pro