On a JLayeredPane with and without layout manager I have a repeated unpredictable problem.

The preview display is fine but when I run it swing components do not appear to be there.

Here is one example.

Every thing worked fine in preview and when run. Then I changed a jLabel  text in the properties window from Jlabel10 
to "".    Looked at it in preview it was fine, then hit the run icon and all of the swing components could not be seen.

I found the cause to be in the generated code section. setbounds height and width were change to -1 ,-1.


Before
        tempSR.setBounds(530, 265, 51, 14);
        tempOut.setBounds(50, 10, 51, 14);
        tempPS.setBounds(250, 80, 45, 14);
        tempPR.setBounds(250, 215, 48, 14);
        ConnectButton.setBounds(690, 20, 90, 23);
        exitButton.setBounds(690, 60, 90, 23);
        hostReset.setBounds(690, 200, 90, 23);
        injectLED.setBounds(454, 140, 10, 11);
        targetTemp.setBounds(570, 50, 80, 17);
       refreshButton.setBounds(690, 160, 90, 23);
 
After

        tempSR.setBounds(530, 265, -1, -1);
        tempOut.setBounds(50, 10, -1, -1);
        tempPS.setBounds(250, 80, -1, -1);
        tempPR.setBounds(250, 215, -1, -1);
        ConnectButton.setBounds(690, 20, 90, -1);
        exitButton.setBounds(690, 60, 90, -1);
        hostReset.setBounds(690, 200, 90, -1);
        injectLED.setBounds(454, 140, 10, -1);
        targetTemp.setBounds(570, 50, 80, -1);
        refreshButton.setBounds(690, 160, 90, -1);

I created a testThis method and pasted the Before code into it, then called it at startup and everything looked ok 
again.

It does not specifically  happen when the text of a label is changed.  Maybe when a component is added or resized or a 
new variable is added to the project. As I said it is not predictable but the result is always the same setBounds 
height and width set to -1 in the generated code section. Everything  may work fine four hours then it happens.

thanks