![]() ![]() I don’t like this pattern, for several reasons: Reuse (and cast) the holder object for reused row views. ![]() Set the instance of the holder as the top-level view’s tag with setTag(Object). ![]() One implementation you see described all over the Internet is called “the holder pattern.” In a nutshell, it entails these steps:Ĭreate a “holder” class with fields to store child views of the row.įor each new inflated row, create a holder instance and assign its fields to the results of calling findViewById(int) for each child view. Since this is such a common problem, patterns have emerged. Take advantage of view recycling when scrolling.Įfficiently identify and populate child views with data. Use a custom layout to define the arrangement of child views. When creating custom views for a ListView or other AdapterView, we have a few requirements: You can find the code for this example project on GitHub. You can see what it looks like in the screen shot below. The Goalįor demonstration purposes, we’ll create a typical simple custom ListView row with an ImageView and two TextViews arranged inside a RelativeLayout parent. In this post, we explore an alternative that uses a subclass of RelativeLayoutto encapsulate the customization work. But the Holder pattern is clumsy and full of boilerplate, and we can do better. When that happens, you’ll probably reach for the Holder pattern. Every Android programmer will at some point customize a ListView row by creating their own layout and populating it with data. ![]()
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