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Thread: signal when QList is not empty

  1. #1
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    Default signal when QList is not empty

    How can I create a signal, when a QList is not empty?
    So when I append an item, the signal should be emitted.

  2. #2
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    Default Re: signal when QList is not empty

    where are you stuck? It should be very easy. Check QList::isEmpty() and emit the signal.

  3. #3
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    Default Re: signal when QList is not empty

    So you tell me I manually have to check, if my QList is empty. In other words: every append should then emit the signal.
    But is there no automatic way to connect this append to a signal?

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    Default Re: signal when QList is not empty

    there is no automatic way to have a qlist emit a signal. It isnt even a QObject so has no ability to 'emit'.

    And why would every append have to emit a signal? Check for size()==1, then signal. It's a trivial problem...
    Last edited by amleto; 2nd November 2011 at 19:38. Reason: empty -> size == 1
    If you have a problem, CUT and PASTE your code. Do not retype or simplify it. Give a COMPLETE and COMPILABLE example of your problem. Otherwise we are all guessing the problem from a fabrication where relevant details are often missing.

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