Question

I am creating dynamic buttons and dynamic button handlers inside of a JPanel, and thus am selecting them again using the “Panel.getComponentAt(x, y)” method.

This method can obviously select from an area that has nothing in it, and this would return a null pointer exception as expected.

I need a way to check whether or not it is selecting an actual component so it does not throw the error, should I just use a try and catch block here? or is there something more elegant? I have tried “isValid()” on a whim, and this doesn’t not seem to be what I’m looking for.

Many Thanks

Answer 1

From javadoc for Container#getComponentAt()

null if the component does not contain the position. If there is no
child component at the requested point and the point is within the
bounds of the container the container itself is returned; otherwise
the top-most child is returned.

so you can do

Component c = Panel1.getComponentAt(x, y);

if ( c!= null && c != Panel1)
{
   // a child component was found
   ...
}