不明白哪里出了问题，第二天脑袋都碎了...
我想将 TabLayout 与 2 个选项卡一起使用，其中第一个 RecyclerView 与 ArtistModel， 但是当我用 RecyclerView 给 Fragment 充气时，会出现这个错误。
这是我的代码。 fragment
package com.shagi.yandex.lookart.fragment;
import android.app.Fragment;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.shagi.yandex.lookart.JsonHelper;
import com.shagi.yandex.lookart.MainActivity;
import com.shagi.yandex.lookart.R;
import com.shagi.yandex.lookart.adaptor.ArtistsAdapter;
import com.shagi.yandex.lookart.pojo.Artist;
import java.util.List;
import java.util.concurrent.ExecutionException;
/**
* A simple {@link Fragment} subclass.
*/
public class ArtistsFragment extends Fragment {
private RecyclerView rvArtists;
private RecyclerView.LayoutManager layoutManager;
private ArtistsAdapter adapter;
private List<Artist> artists;
public MainActivity activity;
public ArtistsFragment() {
// Required empty public constructor
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
if (getActivity() != null) {
activity = (MainActivity) getActivity();
}
loadArtistModels();
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_artists, container, false);
rvArtists = (RecyclerView) rootView.findViewById(R.id.rvArtists);
layoutManager = new LinearLayoutManager(getActivity());
rvArtists.setLayoutManager(layoutManager);
artists = loadArtistModels();
adapter = new ArtistsAdapter(artists);
rvArtists.setAdapter(adapter);
// Inflate the layout for this fragment
return rootView;
}
private List<Artist> loadArtistModels() {
try {
return new JsonHelper().execute().get();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
return null;
}
}
适配器
package com.shagi.yandex.lookart.adaptor;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import com.shagi.yandex.lookart.DownloadImageTask;
import com.shagi.yandex.lookart.R;
import com.shagi.yandex.lookart.pojo.Artist;
import java.util.List;
/**
* Created by Shagi on 06.04.2016.
*/
public class ArtistsAdapter extends RecyclerView.Adapter<ArtistsAdapter.ViewHolder> {
List<Artist> artists;
public ArtistsAdapter(List<Artist> artists) {
this.artists = artists;
}
@Override
public ArtistsAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.model_artist, parent, false);
ImageView smallCover = (ImageView) v.findViewById(R.id.small_cover);
TextView name = (TextView) v.findViewById(R.id.tvArtistName);
TextView style = (TextView) v.findViewById(R.id.tvStyle);
TextView albums = (TextView) v.findViewById(R.id.tvAlbums);
return new ViewHolder(parent, smallCover, name, style, albums);
}
@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
Artist artist = artists.get(position);
new DownloadImageTask(holder.smallCover).execute(artist.getCover().getSmall());
holder.artistName.setText(artist.getName());
String style = "";
for (String string : artist.getGenres()) {
style += string + " ";
}
holder.artistStyle.setText(style);
String albums = "альбомов " + artist.getAlbums() + ", треков " + artist.getTracks();
holder.artistAlbums.setText(albums);
}
@Override
public int getItemCount() {
return artists.size();
}
public static class ViewHolder extends RecyclerView.ViewHolder {
// each data item is just a string in this case
public ImageView smallCover;
public TextView artistName;
public TextView artistStyle;
public TextView artistAlbums;
public ViewHolder(View v, ImageView img, TextView artistName, TextView artistStyle, TextView artistAlbums) {
super(v);
smallCover = img;
this.artistName = artistName;
this.artistStyle = artistStyle;
this.artistAlbums = artistAlbums;
}
}
}
和MainActivity
package com.shagi.yandex.lookart;
import android.app.FragmentManager;
import android.os.Bundle;
import android.support.design.widget.TabLayout;
import android.support.v4.content.ContextCompat;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import com.shagi.yandex.lookart.adaptor.TabAdaptor;
import com.shagi.yandex.lookart.fragment.SplashFragment;
public class MainActivity extends AppCompatActivity {
FragmentManager fragmentManager;
PreferenceHelper preferenceHelper;
TabAdaptor tabAdaptor;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
PreferenceHelper.getInstance().init(getApplicationContext());
preferenceHelper = PreferenceHelper.getInstance();
fragmentManager = getFragmentManager();
//runSplash();
setUI();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
MenuItem splashItem = menu.findItem(R.id.action_splash);
splashItem.setChecked(preferenceHelper.getBoolean(PreferenceHelper.SPLASH_IS_INVISIBLE));
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_splash) {
item.setChecked(!item.isChecked());
preferenceHelper.putBoolean(PreferenceHelper.SPLASH_IS_INVISIBLE, item.isChecked());
return true;
}
return super.onOptionsItemSelected(item);
}
public void runSplash() {
if (!preferenceHelper.getBoolean(PreferenceHelper.SPLASH_IS_INVISIBLE)) {
SplashFragment splashFragment = new SplashFragment();
fragmentManager.beginTransaction()
.replace(R.id.content_frame, splashFragment).addToBackStack(null).commit();
}
}
public void setUI() {
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
if (toolbar != null) {
toolbar.setTitleTextColor(ContextCompat.getColor(getApplicationContext(), R.color.white));
setSupportActionBar(toolbar);
}
TabLayout tabLayout = (TabLayout) findViewById(R.id.tab_layout);
tabLayout.addTab(tabLayout.newTab().setText(R.string.artists_tab));
tabLayout.addTab(tabLayout.newTab().setText(R.string.selected_artist_tab));
final ViewPager viewPager = (ViewPager) findViewById(R.id.pager);
tabAdaptor = new TabAdaptor(fragmentManager, 2);
viewPager.setAdapter(tabAdaptor);
viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
@Override
public void onTabSelected(TabLayout.Tab tab) {
viewPager.setCurrentItem(tab.getPosition());
}
@Override
public void onTabUnselected(TabLayout.Tab tab) {
}
@Override
public void onTabReselected(TabLayout.Tab tab) {
}
});
}
}
堆栈跟踪按要求
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:4066)
at android.view.ViewGroup.addView(ViewGroup.java:3916)
at android.view.ViewGroup.addView(ViewGroup.java:3857)
at android.support.v7.widget.RecyclerView$5.addView(RecyclerView.java:585)
at android.support.v7.widget.ChildHelper.addView(ChildHelper.java:107)
at android.support.v7.widget.RecyclerView$LayoutManager.addViewInt(RecyclerView.java:6249)
at android.support.v7.widget.RecyclerView$LayoutManager.addView(RecyclerView.java:6207)
at android.support.v7.widget.RecyclerView$LayoutManager.addView(RecyclerView.java:6195)
at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1384)
at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1333)
at android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:562)
at android.support.v7.widget.RecyclerView.dispatchLayout(RecyclerView.java:2900)
at android.support.v7.widget.RecyclerView.onLayout(RecyclerView.java:3071)
at android.view.View.layout(View.java:16001)
at android.view.ViewGroup.layout(ViewGroup.java:5181)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:639)
at android.widget.FrameLayout.onLayout(FrameLayout.java:574)
at android.view.View.layout(View.java:16001)
at android.view.ViewGroup.layout(ViewGroup.java:5181)
at android.support.v4.view.ViewPager.onLayout(ViewPager.java:1627)
at android.view.View.layout(View.java:16001)
at android.view.ViewGroup.layout(ViewGroup.java:5181)
at android.support.design.widget.CoordinatorLayout.layoutChild(CoordinatorLayout.java:1037)
at android.support.design.widget.CoordinatorLayout.onLayoutChild(CoordinatorLayout.java:747)
at android.support.design.widget.ViewOffsetBehavior.onLayoutChild(ViewOffsetBehavior.java:42)
at android.support.design.widget.AppBarLayout$ScrollingViewBehavior.onLayoutChild(AppBarLayout.java:1133)
at android.support.design.widget.CoordinatorLayout.onLayout(CoordinatorLayout.java:760)
at android.view.View.layout(View.java:16001)
at android.view.ViewGroup.layout(ViewGroup.java:5181)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:639)
at android.widget.FrameLayout.onLayout(FrameLayout.java:574)
at android.view.View.layout(View.java:16001)
at android.view.ViewGroup.layout(ViewGroup.java:5181)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:639)
at android.widget.FrameLayout.onLayout(FrameLayout.java:574)
at android.view.View.layout(View.java:16001)
at android.view.ViewGroup.layout(ViewGroup.java:5181)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1959)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1813)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1722)
at android.view.View.layout(View.java:16001)
at android.view.ViewGroup.layout(ViewGroup.java:5181)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:639)
at android.widget.FrameLayout.onLayout(FrameLayout.java:574)
at android.view.View.layout(View.java:16001)
at android.view.ViewGroup.layout(ViewGroup.java:5181)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1959)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1813)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1722)
at android.view.View.layout(View.java:16001)
at android.view.ViewGroup.layout(ViewGroup.java:5181)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:639)
at android.widget.FrameLayout.onLayout(FrameLayout.java:574)
at android.view.View.layout(View.java:16001)
at android.view.ViewGroup.layout(ViewGroup.java:5181)
at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2467)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2164)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1282)
at android.
如有不明白之处，请追问。看来我自己解决不了。
最佳答案
您应该在 onCreateView() 方法中将 View v 而不是 parent 传递给 ViewHolder。此外，最好使用 initialise Views 在 Viewholder 中，而不是在 onCreateView()
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.model_artist, parent, false);
更新这一行
return new ViewHolder(parent, smallCover, name, style, albums);
到
return new ViewHolder(v, smallCover, name, style, albums);
关于android - 错误 : The specified child already has a parent. 您必须先在 child 的 parent 上调用 removeView()，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/36485135/
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