kasgoku kasgoku - 6 months ago 33
Android Question

Call removeView() on the child's parent first

First a little background:

I have a layout inside a scrollview. At first, when the user scrolls on the screen, the scrollview scrolls. However, after a certain amount of scroll, I was to disable the scroll on the scroll view the move the "scroll focus" onto a webview inside the child layout. This way, the scrollview sticks and all the scroll events go to the webview inside it.

So, for a solution, when the scroll threshold is reached, I remove the child layout from the scrollview and put it in scrollview's parent.(And make the scrollview invisible).

// Remove the child view from the scroll view
scrollView.removeView(scrollChildLayout);

// Get scroll view out of the way
scrollView.setVisibility(View.GONE);

// Put the child view into scrollview's parent view
parentLayout.addView(scrollChildLayout);


General Idea: (-> means contains)

Before: parentlayout -> scrollview -> scrollChildLayout

After : parentLayout -> scrollChildLayout

The above code is giving me this exception:

java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
at android.view.ViewGroup.addViewInner(ViewGroup.java:1976)
at android.view.ViewGroup.addView(ViewGroup.java:1871)
at android.view.ViewGroup.addView(ViewGroup.java:1828)
at android.view.ViewGroup.addView(ViewGroup.java:1808)


Do you know what's going on? I am clearly calling removeView on the parent.

Answer

Solution:

((ViewGroup)scrollChildLayout.getParent()).removeView(scrollChildLayout);
//scrollView.removeView(scrollChildLayout);

Use the child element to get a reference to the parent. Cast the parent to a ViewGroup so that you get access to the removeView method and use that.

Thanks to @Dongshengcn for the solution