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RecyclerViewの使用エラー:指定された子には既に親があります

新しいRecyvlerView Adapterを使用してlistViewを作成しようとしています。 Android開発者リソースにある正確なガイドに従いました。しかし、これは奇妙なエラーを与えています:指定された子はすでに親を持っています最初に、子の親でremoveView()を呼び出す必要があります。最新のSDKがあり、gradleで依存関係も定義しています。

MyActivity(メインアクティビティ):

public class MyActivity extends Activity {

    private RecyclerView mRecyclerView;
    private RecyclerView.Adapter mAdapter;
    private RecyclerView.LayoutManager mLayoutManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_my);
        mRecyclerView = (RecyclerView) findViewById(R.id.my_recycler_view);

        // use this setting to improve performance if you know that changes
        // in content do not change the layout size of the RecyclerView
        mRecyclerView.setHasFixedSize(true);

        // use a linear layout manager
        mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
        mRecyclerView.setItemAnimator(new DefaultItemAnimator());

        // specify an adapter (see also next example)
        mAdapter = new MyAdapter(new String[]{"Zain", "Nadeem"});

        mRecyclerView.setAdapter(mAdapter);
    }
}

MyAdapter:

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
    private String[] mDataset;    
    // Provide a reference to the views for each data item
    // Complex data items may need more than one view per item, and
    // you provide access to all the views for a data item in a view holder
    // Provide a suitable constructor (depends on the kind of dataset)
    public MyAdapter(String[] myDataset) {
        mDataset = myDataset;
    }

    // Create new views (invoked by the layout manager)
    @Override
    public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        // create a new view
        LayoutInflater inflater = LayoutInflater.from(parent.getContext());  

        View v = inflater.inflate(R.layout.my_text_view, parent, true);
        ViewHolder vh = new ViewHolder(v);
        return vh;
    }

    // Replace the contents of a view (invoked by the layout manager)
    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        // - get element from your dataset at this position
        // - replace the contents of the view with that element    
        holder.mTextView.setText(mDataset[position]);
    }

    // Return the size of your dataset (invoked by the layout manager)
    @Override
    public int getItemCount() {
        return mDataset.length;
    }

    public static class ViewHolder extends RecyclerView.ViewHolder {
        // each data item is just a string in this case
        public TextView mTextView;
        public ViewHolder(View v) {
            super(v);
            mTextView = (TextView) v.findViewById(R.id.item_title);
        }
    }
}

my_text_view.xml(リストアイテムのレイアウト):

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:Android="http://schemas.Android.com/apk/res/Android"
    Android:layout_width="fill_parent"
    Android:layout_height="80dp"

    >
    <!-- title -->
    <TextView
        Android:id="@+id/item_title"
        Android:layout_width="fill_parent"
        Android:layout_height="wrap_content"
        Android:textColor="@Android:color/darker_gray"
        Android:layout_marginLeft="8dp"
        Android:layout_marginRight="8dp"
        Android:layout_marginTop="8dp"
        Android:textSize="22dp" />

</RelativeLayout>

activity_my.xml(メインアクティビティ):

<LinearLayout xmlns:Android="http://schemas.Android.com/apk/res/Android"
    xmlns:tools="http://schemas.Android.com/tools"
    xmlns:card_view="http://schemas.Android.com/apk/res-auto"
    Android:layout_height="fill_parent"
    Android:layout_width="fill_parent"
    Android:background="@Android:color/holo_orange_light"
    >
    <!-- A CardView that contains a TextView -->
    <Android.support.v7.widget.RecyclerView
        Android:id="@+id/my_recycler_view"
        Android:scrollbars="vertical"
        Android:layout_width="match_parent"
        Android:layout_height="match_parent"
        tools:context=".MyActivity"/>
    </LinearLayout>

次に、logcatの出力を示します。

10-28 01:20:30.287  22729-22729/osman.zaingz.com.Lollipop E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: osman.zaingz.com.Lollipop, PID: 22729
    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:3562)
            at Android.view.ViewGroup.addView(ViewGroup.Java:3415)
            at Android.view.ViewGroup.addView(ViewGroup.Java:3360)
            at Android.support.v7.widget.RecyclerView$4.addView(RecyclerView.Java:322)
            at Android.support.v7.widget.ChildHelper.addView(ChildHelper.Java:79)
            at Android.support.v7.widget.RecyclerView$LayoutManager.addViewInt(RecyclerView.Java:4845)
            at Android.support.v7.widget.RecyclerView$LayoutManager.addView(RecyclerView.Java:4803)
            at Android.support.v7.widget.RecyclerView$LayoutManager.addView(RecyclerView.Java:4791)
            at Android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.Java:1316)
            at Android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.Java:1265)
            at Android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.Java:522)
            at Android.support.v7.widget.RecyclerView.dispatchLayout(RecyclerView.Java:1918)
            at Android.support.v7.widget.RecyclerView.onLayout(RecyclerView.Java:2155)
            at Android.view.View.layout(View.Java:14817)
            at Android.view.ViewGroup.layout(ViewGroup.Java:4631)
            at Android.widget.LinearLayout.setChildFrame(LinearLayout.Java:1671)
            at Android.widget.LinearLayout.layoutHorizontal(LinearLayout.Java:1660)
            at Android.widget.LinearLayout.onLayout(LinearLayout.Java:1436)
            at Android.view.View.layout(View.Java:14817)
            at Android.view.ViewGroup.layout(ViewGroup.Java:4631)
            at Android.widget.FrameLayout.layoutChildren(FrameLayout.Java:453)
            at Android.widget.FrameLayout.onLayout(FrameLayout.Java:388)
            at Android.view.View.layout(View.Java:14817)
            at Android.view.ViewGroup.layout(ViewGroup.Java:4631)
            at com.Android.internal.widget.ActionBarOverlayLayout.onLayout(ActionBarOverlayLayout.Java:374)
            at Android.view.View.layout(View.Java:14817)
            at Android.view.ViewGroup.layout(ViewGroup.Java:4631)
            at Android.widget.FrameLayout.layoutChildren(FrameLayout.Java:453)
            at Android.widget.FrameLayout.onLayout(FrameLayout.Java:388)
            at Android.view.View.layout(View.Java:14817)
            at Android.view.ViewGroup.layout(ViewGroup.Java:4631)
            at Android.view.ViewRootImpl.performLayout(ViewRootImpl.Java:1983)
            at Android.view.ViewRootImpl.performTraversals(ViewRootImpl.Java:1740)
            at Android.view.ViewRootImpl.doTraversal(ViewRootImpl.Java:996)
            at Android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.Java:5600)
            at Android.view.Choreographer$CallbackRecord.run(Choreographer.Java:761)
            at Android.view.Choreographer.doCallbacks(Choreographer.Java:574)
            at Android.view.Choreographer.doFrame(Choreographer.Java:544)
            at Android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.Java:747)
            at Android.os.Handler.handleCallback(Handler.Java:733)
            at Android.os.Handler.dispatchMessage(Handler.Java:95)
            at Android.os.Looper.loop(Looper.Java:136)
            at Android.app.ActivityThread.main(ActivityThread.Java:5001)
            at Java.lang.reflect.Method.invoke(Native Method)
            at com.Android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.Java:785)
            at com.Android.internal.os.ZygoteInit.main(ZygoteInit.Java:601)
52
zaingz

膨張させるとき、ビューをその親にアタッチしないでください。あなたが書いた:

View v = inflater.inflate(R.layout.my_text_view, parent, true);

どちらにする必要があります:

View v = inflater.inflate(R.layout.my_text_view, parent, false);
112
EC84B4
<RelativeLayout xmlns:Android="http://schemas.Android.com/apk/res/Android"
Android:layout_width="fill_parent"
Android:layout_height="80dp">

<TextView
    Android:id="@+id/item_title"
    Android:layout_width="fill_parent"
    Android:layout_height="wrap_content"
    Android:textColor="@Android:color/darker_gray"
    Android:layout_marginLeft="8dp"
    Android:layout_marginRight="8dp"
    Android:layout_marginTop="8dp"
    Android:textSize="22dp" />

</RelativeLayout>

RelativeLayoutこれはID item_titleのTextViewの親です。次に、RecyclerViewが親を持つTextViewを追加しようとすると、例外がスローされます。

このコードを試してください:

public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent,
                                                   int viewType) {
        // create a new view
        Log.d(TAG, "onCreateViewHolder");
        RelativeLayout v = (RelativeLayout)LayoutInflater.from(parent.getContext())
                .inflate(R.layout.list_item, parent, false);
        // set the view's size, margins, paddings and layout parameters
        View view = v.findViewById(R.id.text1);
        v.removeView(view);
        ViewHolder vh = new ViewHolder(view);
        return vh;
    }
17
Magadan Artem

リサイクラービューを非常に速くスクロールした場合も同様です。私の場合は、DiffUtilsを使用してアイテムを挿入/移動/ ...し、recyclerviewアニメーションの終了前にコードのどこかにルートレイアウト(および、recyclerview)でTransitionManager.beginDelayedTransition(view)を呼び出しました。

14
Victor

`TransitionManager.beginDelayedTransition();を削除することで解決しました。

1
Shivam Yadav

少し遅いかもしれませんが、同じ問題(recyclerview-v7:26.1.0)があり、その理由は、現在表示されている位置でリストを(scrollToPosition()メソッドで)スクロールしようとしたためです。スクロールする前に位置のチェックを追加した後(非表示の位置でのみスクロール)、問題は解決しました

0
Denis