mapToItem Returns (0,0) in Component.onCompleted Due to Incomplete Layout – How to Detect Layout Readiness?
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I have a public method that needs to be called when the page creation is complete. Its purpose is to identify the controls closest to the top-left corner and the bottom-right corner within the page. To achieve this, I'm using mapToItem. However, in one specific page, calling this method in the root component's Component.onCompleted handler fails, as mapToItem returns (0, 0).
I've determined that the issue occurs because the layout isn't fully complete even after the interface creation succeeds. How can I reliably detect the timing when the page layout is fully ready?
The layout of this problematic page consists of a Column inside a Flickable. As a workaround, I'm currently calling the method in response to the Column's positioningComplete signal (not positionCompleted—I believe that's a typo in the original), and mapToItem works correctly there.
That said, I have many other similar pages where I directly use mapToItem in the root component's onCompleted, and they all function normally without issues.
What factors could generally cause the layout completion to lag behind the component creation in some cases? Is the success in my other pages just a matter of "luck," or are there specific differences I should investigate?