Android recyclerview未连接适配器;跳过布局

Android recyclerview未连接适配器;跳过布局,android,android-recyclerview,Android,Android Recyclerview,刚刚在我的代码中实现了RecyclerView,替换了ListView 一切正常。显示数据 但正在记录错误消息: 15:25:53.476 E/RecyclerView:未连接适配器;跳过布局 15:25:53.655 E/RecyclerView:未连接适配器;跳过布局 对于以下代码: ArtistArrayAdapter adapter = new ArtistArrayAdapter(this, artists); recyclerView = (RecyclerView) findVi

刚刚在我的代码中实现了
RecyclerView
,替换了
ListView

一切正常。显示数据

但正在记录错误消息:

15:25:53.476 E/RecyclerView:未连接适配器;跳过布局
15:25:53.655 E/RecyclerView:未连接适配器;跳过布局
对于以下代码:

ArtistArrayAdapter adapter = new ArtistArrayAdapter(this, artists);
recyclerView = (RecyclerView) findViewById(R.id.cardList);
recyclerView.setHasFixedSize(true);
recyclerView.setAdapter(adapter);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
如您所见,我已为
RecyclerView
附加了一个适配器。 那么,为什么我总是犯这个错误呢


我已经阅读了与同一问题相关的其他问题,但没有一个有帮助。

您是否可以确保从延迟异步回调之外的“主”线程调用这些语句(例如在
onCreate()
方法中)。 只要我从“延迟”方法调用相同的语句。在我的例子a
ResultCallback
中,我得到了相同的消息

在我的
Fragment
中,从
ResultCallback
方法内部调用下面的代码会产生相同的消息。将代码移动到我的应用程序中的
onConnected()
方法后,消息消失了

LinearLayoutManager llm = new LinearLayoutManager(this);
llm.setOrientation(LinearLayoutManager.VERTICAL);
list.setLayoutManager(llm);
list.setAdapter( adapter );

您是否可以确保从延迟异步回调之外的“主”线程调用这些语句(例如在
onCreate()
方法中)。 只要我从“延迟”方法调用相同的语句。在我的例子a
ResultCallback
中,我得到了相同的消息

在我的
Fragment
中,从
ResultCallback
方法内部调用下面的代码会产生相同的消息。将代码移动到我的应用程序中的
onConnected()
方法后,消息消失了

LinearLayoutManager llm = new LinearLayoutManager(this);
llm.setOrientation(LinearLayoutManager.VERTICAL);
list.setLayoutManager(llm);
list.setAdapter( adapter );

在我修复代码中的两个问题之前,我一直收到相同的两条错误消息:

(1) 默认情况下,当您在
RecyclerView.Adapter
中实现方法时,它会生成:

@Override
public int getItemCount() {
    return 0;
}
确保更新代码,使其显示:

@Override
public int getItemCount() {
    return artists.size();
}
显然,如果您的项目中没有项目,那么您将在屏幕上显示零个项目

(2) 我并没有像上面的答案那样做:

(3) 编辑:奖金: 还要确保您的
RecyclerView
设置如下:

<android.support.v7.widget.RecyclerView
    android:id="@+id/RecyclerView"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    />
<view
    android:id="@+id/RecyclerView"
    class="android.support.v7.widget.RecyclerView"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />
class SettingsFragment : PreferenceFragmentCompat() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        val inflater = LayoutInflater.from(context)
        inflater.inflate(R.layout.fragment_settings, null)
    }

    override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
        // Missing this line here:
        //   setPreferencesFromResource(R.xml.settings, rootKey)
    }
}

不是这样的:

<android.support.v7.widget.RecyclerView
    android:id="@+id/RecyclerView"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    />
<view
    android:id="@+id/RecyclerView"
    class="android.support.v7.widget.RecyclerView"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />
class SettingsFragment : PreferenceFragmentCompat() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        val inflater = LayoutInflater.from(context)
        inflater.inflate(R.layout.fragment_settings, null)
    }

    override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
        // Missing this line here:
        //   setPreferencesFromResource(R.xml.settings, rootKey)
    }
}


我看过一些使用后一种方法的教程。虽然它有效,但我认为它也会产生这种错误

在修复代码中的两个问题之前,我一直收到相同的两条错误消息:

(1) 默认情况下,当您在
RecyclerView.Adapter
中实现方法时,它会生成:

@Override
public int getItemCount() {
    return 0;
}
确保更新代码,使其显示:

@Override
public int getItemCount() {
    return artists.size();
}
显然,如果您的项目中没有项目,那么您将在屏幕上显示零个项目

(2) 我并没有像上面的答案那样做:

(3) 编辑:奖金: 还要确保您的
RecyclerView
设置如下:

<android.support.v7.widget.RecyclerView
    android:id="@+id/RecyclerView"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    />
<view
    android:id="@+id/RecyclerView"
    class="android.support.v7.widget.RecyclerView"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />
class SettingsFragment : PreferenceFragmentCompat() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        val inflater = LayoutInflater.from(context)
        inflater.inflate(R.layout.fragment_settings, null)
    }

    override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
        // Missing this line here:
        //   setPreferencesFromResource(R.xml.settings, rootKey)
    }
}

不是这样的:

<android.support.v7.widget.RecyclerView
    android:id="@+id/RecyclerView"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    />
<view
    android:id="@+id/RecyclerView"
    class="android.support.v7.widget.RecyclerView"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />
class SettingsFragment : PreferenceFragmentCompat() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        val inflater = LayoutInflater.from(context)
        inflater.inflate(R.layout.fragment_settings, null)
    }

    override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
        // Missing this line here:
        //   setPreferencesFromResource(R.xml.settings, rootKey)
    }
}


我看过一些使用后一种方法的教程。虽然它有效,但我认为它也会产生这种错误

如果在创建阶段未设置适配器,则会发生这种情况:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity);
    mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
    ....
}

public void onResume() {
    super.onResume();
    mRecyclerView.setAdapter(mAdapter);
    ....
}
只需将适配器设置移到onCreate中,并使用空数据,然后在进行数据调用时:

mAdapter.notifyDataSetChanged();

如果在创建阶段未设置适配器,则会发生这种情况:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity);
    mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
    ....
}

public void onResume() {
    super.onResume();
    mRecyclerView.setAdapter(mAdapter);
    ....
}
只需将适配器设置移到onCreate中,并使用空数据,然后在进行数据调用时:

mAdapter.notifyDataSetChanged();

我和你有同样的情况,显示是正常的,但错误出现在locat。 这就是我的解决方案: (1) 在CREATE()上初始化RecyclerView&bind适配器

(2) 获取数据时调用notifyDataStateChanged

adapter.notifyDataStateChanged();
在recyclerView的源代码中,还有其他线程来检查数据的状态

public RecyclerView(Context context, @Nullable AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    this.mObserver = new RecyclerView.RecyclerViewDataObserver(null);
    this.mRecycler = new RecyclerView.Recycler();
    this.mUpdateChildViewsRunnable = new Runnable() {
        public void run() {
            if(RecyclerView.this.mFirstLayoutComplete) {
                if(RecyclerView.this.mDataSetHasChangedAfterLayout) {
                    TraceCompat.beginSection("RV FullInvalidate");
                    RecyclerView.this.dispatchLayout();
                    TraceCompat.endSection();
                } else if(RecyclerView.this.mAdapterHelper.hasPendingUpdates()) {
                    TraceCompat.beginSection("RV PartialInvalidate");
                    RecyclerView.this.eatRequestLayout();
                    RecyclerView.this.mAdapterHelper.preProcess();
                    if(!RecyclerView.this.mLayoutRequestEaten) {
                        RecyclerView.this.rebindUpdatedViewHolders();
                    }

                    RecyclerView.this.resumeRequestLayout(true);
                    TraceCompat.endSection();
                }

            }
        }
    };
在dispatchLayout()中,我们可以发现其中存在错误:

void dispatchLayout() {
    if(this.mAdapter == null) {
        Log.e("RecyclerView", "No adapter attached; skipping layout");
    } else if(this.mLayout == null) {
        Log.e("RecyclerView", "No layout manager attached; skipping layout");
    } else {

我和你有同样的情况,显示是正常的,但错误出现在locat。 这就是我的解决方案: (1) 在CREATE()上初始化RecyclerView&bind适配器

(2) 获取数据时调用notifyDataStateChanged

adapter.notifyDataStateChanged();
在recyclerView的源代码中,还有其他线程来检查数据的状态

public RecyclerView(Context context, @Nullable AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    this.mObserver = new RecyclerView.RecyclerViewDataObserver(null);
    this.mRecycler = new RecyclerView.Recycler();
    this.mUpdateChildViewsRunnable = new Runnable() {
        public void run() {
            if(RecyclerView.this.mFirstLayoutComplete) {
                if(RecyclerView.this.mDataSetHasChangedAfterLayout) {
                    TraceCompat.beginSection("RV FullInvalidate");
                    RecyclerView.this.dispatchLayout();
                    TraceCompat.endSection();
                } else if(RecyclerView.this.mAdapterHelper.hasPendingUpdates()) {
                    TraceCompat.beginSection("RV PartialInvalidate");
                    RecyclerView.this.eatRequestLayout();
                    RecyclerView.this.mAdapterHelper.preProcess();
                    if(!RecyclerView.this.mLayoutRequestEaten) {
                        RecyclerView.this.rebindUpdatedViewHolders();
                    }

                    RecyclerView.this.resumeRequestLayout(true);
                    TraceCompat.endSection();
                }

            }
        }
    };
在dispatchLayout()中,我们可以发现其中存在错误:

void dispatchLayout() {
    if(this.mAdapter == null) {
        Log.e("RecyclerView", "No adapter attached; skipping layout");
    } else if(this.mLayout == null) {
        Log.e("RecyclerView", "No layout manager attached; skipping layout");
    } else {
只要用这个替换上面的代码就可以了。错误的是在调用布局管理器之前调用了setAdapter(adapter)

只要用这个替换上面的代码就可以了。您所做的错误是在调用布局管理器之前调用了setAdapter(adapter)。

1)创建不执行任何操作的对象:)


2) 再次创建不执行任何操作的:)


虽然这不是最好的解决方案,但它确实有效!希望这有帮助。

1)创建一个什么都不做的:)


2) 再次创建不执行任何操作的:)



虽然这不是最好的解决方案,但它确实有效!希望这是有帮助的。

我有这个问题,一些时间问题是回收视图放入ScrollView对象

检查实现后,原因似乎如下。如果将RecyclerView放入ScrollView,那么在测量步骤中,它的高度是未指定的(因为ScrollView允许任何高度),因此,它等于最小高度(根据实现),这显然是零

您有两个选项可以修复此问题:

  • 将某个高度设置为RecyclerView
  • 将ScrollView.fillViewport设置为true
  • 或者将RecyclerView置于ScrollView之外。在我看来,这是迄今为止最好的选择。如果RecyclerView高度不受限制(将其放入ScrollView时就是这种情况),那么所有适配器的视图都有足够的垂直位置,可以一次创建所有视图。再也没有视图回收了,这有点违背了RecyclerView的目的

  • (android.support.v4.widget.NestedScrollView也可以使用

    在检查实现后,reaso
    MyRecyclerViewAdapter(Context context, List<String> data) {
        this.mInflater = LayoutInflater.from(context); // <-- This is the line most people include me miss
        this.mData = data;
    }
    
    MyRecyclerViewAdapter recyclerAdapter;
    OurDataStuff mData;
    
        ....
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
    
            //Like this:
    
            RecyclerView recyclerView = findViewById(R.id.recyclerView);
            recyclerView.setLayoutManager(new LinearLayoutManager(this));
            recyclerAdapter = new RecyclerAdapter(this, mData); //this, is the context. mData is the data you want to pass if you have any
            recyclerView.setAdapter(recyclerAdapter);
        }
       ....
    
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getContext());
        recyclerviewItems.setLayoutManager(linearLayoutManager);
        someAdapter = new SomeAdapter(getContext(),feedList);
        recyclerviewItems.setAdapter(someAdapter);
    
    public void initializeComments(){
        comments = new ArrayList<>();
    
        comments_myRecyclerView = (RecyclerView) findViewById(R.id.comments_recycler);
        comments_mLayoutManager = new LinearLayoutManager(myContext);
        comments_myRecyclerView.setLayoutManager(comments_mLayoutManager);
    
        updateComments();
        getCommentsData();
    
    }
    
    public void updateComments(){
    
        comments_mAdapter = new CommentsAdapter(comments, myContext);
        comments_myRecyclerView.setAdapter(comments_mAdapter);
    }
    
        override fun onCreateView(inflater: LayoutInflater?, container: ViewGroup?, savedInstanceState: Bundle?): View? {
    
        val rootView =  inflater?.inflate(R.layout.fragment_layout, container, false)
        recyclerView = rootView?.findViewById(R.id.recycler_view_id)
        // rest of my stuff
        recyclerView?.setHasFixedSize(true)
        recyclerView?.layoutManager = viewManager
        recyclerView?.adapter = viewAdapter
        // return the root view
        return rootView
    }
    
      @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    
        View rootView= inflater.inflate(R.layout.fragment_layout,container,false);
        recyclerview= rootView.findViewById(R.id.recycler_view_id);
        return rootView;
    }
    
    @BindView(R.id.recycler_view)
    RecyclerView recyclerView;
    
        @Override
    public View onCreateView(......) {
        View v = ...;
        ButterKnife.bind(this, v);
        setUpRecycler()
     }
    
    public void setUpRecycler(Data data)
       if (recyclerView == null) {
     /*very silly because this will never happen*/
           LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getActivity());
           //more setup
           //...
        }
        recyclerView.setAdapter(new XAdapter(data));
    }
    
    @Override
    public int getItemCount() {
        return list.size();
    }
    
    <?xml version="1.0" encoding="utf-8"?>
    <android.support.v7.widget.RecyclerView
        android:id="@+id/list"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:listitem="@layout/fragment_products"
    
        android:name="Products.ProductsFragment"
        app:layoutManager="LinearLayoutManager"
        tools:context=".Products.ProductsFragment"
    
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"/>
    
    app:layoutManager="android.support.v7.widget.LinearLayoutManager"
    
       <android.support.v7.widget.RecyclerView xmlns:android="http://schemas.android.com/apk/res/android"
            xmlns:app="http://schemas.android.com/apk/res-auto"
            android:id="@+id/recyclerView"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:scrollbars="vertical"
            app:layoutManager="android.support.v7.widget.LinearLayoutManager"
            app:layout_constraintBottom_toTopOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent">
    
        </android.support.v7.widget.RecyclerView>
    
    class SettingsFragment : PreferenceFragmentCompat() {
        override fun onCreate(savedInstanceState: Bundle?) {
            super.onCreate(savedInstanceState)
    
            val inflater = LayoutInflater.from(context)
            inflater.inflate(R.layout.fragment_settings, null)
        }
    
        override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
            // Missing this line here:
            //   setPreferencesFromResource(R.xml.settings, rootKey)
        }
    }
    
     mBinding.serviceProviderCertificates.apply {
                adapter = adapter
                layoutManager =  LinearLayoutManager(activity)
            }
    
    mBinding.serviceProviderCertificates.adapter = adapter
    mBinding.serviceProviderCertificates.layoutManager = LinearLayoutManager(activity)
    
    private void buildRecyclerView(View v) {
            mRecyclerView = v.findViewById(R.id.recycler_view_loan);
            mLayoutManager = new LinearLayoutManager(getActivity());
            ((LinearLayoutManager) mLayoutManager).setOrientation(LinearLayoutManager.VERTICAL);
            mRecyclerView.setLayoutManager(mLayoutManager);
            mAdapter = new LoanAdapter(mExampleList);
            mRecyclerView.setLayoutManager(mLayoutManager);
            mRecyclerView.setAdapter(mAdapter);
    }
    
    @Override
        public int getItemCount() {
            try {
                return mLoanList.size();
            } catch (Exception ex){return 0;}
    
        }
    
       <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recycler_view_chat"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        app:layoutManager="LinearLayoutManager"/>