


Child View Attachment Error in Android
When switching between layouts頻繁, an exception may arise: "The specified child already has a parent. You must call removeView() on the child's parent first."
Cause:
This error occurs when the view, in this case a TextView ("tv"), is already attached to a parent view group (LinearLayout "layout") when attempting to add it again to the new layout.
Context:
The provided code snippet demonstrates a layout-switching mechanism in Android. When the "ConsoleWindow()" method is executed initially, it sets the layout and adds "tv" to the "layout" without issue. However, when the layout is switched to a blank one and then back to the original layout, the error is thrown.
Solution:
The error message suggests the appropriate solution: removing the view from its current parent before adding it to the new parent. To accomplish this:
<code class="java">// TEXTVIEW if(tv.getParent() != null) { ((ViewGroup)tv.getParent()).removeView(tv); // <p>This check ensures that if "tv" is already attached to another parent view group, it is first removed before being added to the new layout, resolving the attachment issue.</p></code>
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