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Thread: Why isn't the MouseListener showing the X and Y cords like I want it to?

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    Default Re: Why isn't the MouseListener showing the X and Y cords like I want it to?

    It appears that animator.getMousePosition() is returning null so that's what's causing the exception.

    But what do I do then?

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    Default Re: Why isn't the MouseListener showing the X and Y cords like I want it to?

    Strange. I was able to get the earlier code to work without exceptions.

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    Default Re: Why isn't the MouseListener showing the X and Y cords like I want it to?

    Yes, the other code that involved the MouseInfo class did work, but I wasn't looking for the mouse position on my computer screen. Just the mouse position on the FountainAnimator object.

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    Default Re: Why isn't the MouseListener showing the X and Y cords like I want it to?

    If you have working code in one program, look at how it works and copy the technique to the other program.

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    Default Re: Why isn't the MouseListener showing the X and Y cords like I want it to?

    OK, if the mouse isn't actually in the component, that call will return null. For some reason, you're not checking the return value, you're just calling a method on it, so you get a NullPointerException when the mouse isn't over the component.

    Leaving aside, for a moment, better designs, you can fix the code you have by simply checking your return value and not using it if it's null:
    ...
    Point pos = animator.getMousePosition();
    if (pos != null) {
        xLocation = pos.getX();
        yLocation = pos.getY();
    }
    ...

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    Default Re: Why isn't the MouseListener showing the X and Y cords like I want it to?

    Yeah, but when I put it in the Component, it still says null.

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    Default Re: Why isn't the MouseListener showing the X and Y cords like I want it to?

    I tried the old code, but am not sure how to apply it to the animator object only.

    Right now it will just show the position of the mouse on my screen, even outside any components.

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    Default Re: Why isn't the MouseListener showing the X and Y cords like I want it to?

    Ok, this time it's relative to the animator object.

    Thanks.


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    Default Re: Why isn't the MouseListener showing the X and Y cords like I want it to?

    Where/when do you want the mouse location?
    If only over a component, use a mouse listener for that component.

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