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POWhat's the quickest way to add several views to a LinearLayout?
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copied!<p>I have a <code>LinearLayout</code> view that already contains several elements. I want to add a lot more Views to it, programmatically. And because this is inside a <code>ScrollView</code>, everything will be scrolled.</p> <p>So what I do is go through my list, and add new instances of my custom View to it. That custom view inflates a XML layout and adds a few methods.</p> <p>This approach works well. The problem is that it's super slow, even without any crazy code... a list with 10 items takes around 500ms to instantiate. As an user experience standpoint, this is hard to swallow.</p> <p>My question is, is this the correct/best approach? Android seems to take a lot of time inflating the layout, even though "R.layout.my_list_item" is super simple. I wonder if there's a way to maybe to reuse "inflated" layouts for additional views, kinda caching the more complex parsing?</p> <p>I've tried doing this with a <code>ListView</code> (and adapter and a wrapper) and it seems to be much faster. The problem is that I can't use a simple <code>ListView</code>; my layout is more complex than a simple list (the <code>LinearLayout</code> itself contains additional custom icons, and it has another parent with even more Views before it's wrapped by the <code>ScrollView</code>).</p> <p>But is there a way to use an adapter for a LinearLayout? Would that be faster than trying to add the views myself?</p> <p>Any help is appreciated. I'd love to make this faster.</p> <p>Code follows.</p> <p><strong>Main Activity:</strong></p> <pre><code>// The LinearLayout that will contain everything lineList = (LinearLayout) findViewById(R.id.lineList); // Add a lot of items for testing for (int i = 0; i < 10; i++) { addListItem("Item number " + i); } protected void addListItem(String __title) { MyListItem li; li = new MyListItem(this); li.setTitle(__title); lineList.addView(li); } </code></pre> <p><strong>MyListItem:</strong></p> <pre><code>public class MyListItem extends RelativeLayout { protected TextView textTitle; public MyListItem(Context __context) { super(__context); init(); } public MyListItem(Context __context, AttributeSet __attrs) { super(__context, __attrs); init(); } public MyListItem(Context __context, AttributeSet __attrs, int __attrsdefStyle) { super(__context, __attrs, __attrsdefStyle); init(); } protected void init() { // Inflate the XML layout LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE); inflater.inflate(R.layout.my_list_item, this); // Create references textTitle = (TextView)findViewById(R.id.textTitle); } public void setTitle(String __text) { textTitle.setText(__text); } } </code></pre> <p>What I'm trying to accomplish is this. Consider this layout:</p> <p><img src="https://i.stack.imgur.com/5eNcu.png" alt="Basic layout"></p> <p>This layout is a <code>FrameLayout</code> (outer box) containing a <code>ImageView</code> (in gray), a <code>TextView</code> (inner rectangle, on top) and a <code>LinearLayout</code> (inner rectangle, on bottom). This <code>LinearLayout</code> rectangle is the one I'm dynamically populating with a few items.</p> <p>After I populate it, I want the final result to be this (where every new rectangle is a new <code>MyListItem</code> instance):</p> <p><img src="https://i.stack.imgur.com/9IVz1.png" alt="Populated layout"></p> <p>That is, everything is scrollable (the background image, for example, is aligned on top). The <code>LinearLayout</code> isn't scrollable by itself (everything else follows) hence why a <code>ListView</code>, from what I know, wouldn't work very well in my case.</p>

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