正如标题所提到的，我遇到了一个问题，其中一个视图有多个父级。是否有使用NavigationBar的特定协议，它会使NestedFragments onItemSelected（）膨胀？我在这个项目中缺少什么？任何指导都将不胜感激。
错误日志：
10-16 17:27:02.282: E/AndroidRuntime(18090): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.inviscidlabs.schooled/com.inviscidlabs.schooled.ActivityClassEdit}: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.app.ActivityThread.access$800(ActivityThread.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.app.ActivityThread$H.handleMessage(ActivityThread.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.os.Handler.dispatchMessage(Handler.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.os.Looper.loop(Looper.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.app.ActivityThread.main(ActivityThread.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at java.lang.reflect.Method.invokeNative(Native Method)
10-16 17:27:02.282: E/AndroidRuntime(18090): at java.lang.reflect.Method.invoke(Method.java:515)
10-16 17:27:02.282: E/AndroidRuntime(18090): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at dalvik.system.NativeStart.main(Native Method)
10-16 17:27:02.282: E/AndroidRuntime(18090): Caused by: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.view.ViewGroup.addViewInner(ViewGroup.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.view.ViewGroup.addView(ViewGroup.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.view.ViewGroup.addView(ViewGroup.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.view.ViewGroup.addView(ViewGroup.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.support.v4.app.NoSaveStateFrameLayout.wrap(NoSaveStateFrameLayout.java:40)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:946)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1121)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1484)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.support.v4.app.Fragment.performStart(Fragment.java:1525)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:972)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1121)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1103)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.support.v4.app.FragmentManagerImpl.dispatchStart(FragmentManager.java:1906)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:588)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.app.Instrumentation.callActivityOnStart(Instrumentation.java)
10-16 17:27:02.282: E/AndroidRuntime(18090): at android.app.Activity.performStart(Activity.
违规活动：
public class ActivityClassEdit extends FragmentActivity{
//Variables
//Fragments
private ContainerFragmentCriteria frag_Criteria;
private DrawerLayout mDrawerLayout;
private ListView mDrawerList;
private ActionBarDrawerToggle mDrawerToggle;
//used as the effective ArrayAdapter for the NavigationDrawer
private ClassEditDrawerAdapter mNavAdapter;
private CharSequence sDrawerTitle;
private CharSequence sTitle;
//Serves as List of Strings to populate Nav Drawer's ListView of options
List<ClassEditDrawerItem> navOptions;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_classedit);
//Initialize List
navOptions= new ArrayList<ClassEditDrawerItem>();
sTitle=sDrawerTitle=getTitle();
mDrawerLayout = (DrawerLayout) findViewById(R.id.ace_drawer);
mDrawerList=(ListView) findViewById(R.id.ace_drawer_list);
navOptions.add(new ClassEditDrawerItem("Criteria", R.drawable.ic_launcher));
mNavAdapter = new ClassEditDrawerAdapter(this, R.layout.item_navbar, navOptions);
mDrawerList.setAdapter(mNavAdapter);
//Set ListView onClickListener
mDrawerList.setOnItemClickListener(new DrawerItemClickListener());
//Set up the home button to open the nav drawer
getActionBar().setDisplayHomeAsUpEnabled(true);
getActionBar().setHomeButtonEnabled(true);
mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,
R.drawable.ic_launcher, R.string.hello_world,
R.string.name);
mDrawerLayout.setDrawerListener(mDrawerToggle);
//Select first item by default
if(savedInstanceState==null){
SelectItem(0);
}
//What to do when Item is Selected
public void SelectItem(int position){
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
switch(position){
//Class Edit
case 0:
if(frag_Criteria==null){
frag_Criteria = new ContainerFragmentCriteria();
}
transaction.replace(R.id.ace_frame, frag_Criteria);
transaction.commit();
break;
}
Toast.makeText(this, String.valueOf(position), Toast.LENGTH_LONG).show();
}
private class DrawerItemClickListener implements ListView.OnItemClickListener {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
SelectItem(position);
}
}
自动充气的第一个片段：
public class ContainerFragmentCriteria extends Fragment{
private FragmentManager fm;
private boolean insertMode;
//=====================ACTIVITY LIFECYCLE==============================
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.frag_container_criteria, container, false);
return v;
}
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
//Instantiate Fragments, set Arguments
FragmentCriteriaEdit fCrE= new FragmentCriteriaEdit();
FragmentCriteriaList fCrL = new FragmentCriteriaList();
Bundle fCritListArguments = new Bundle();
fCritListArguments.putBoolean(CM.BKEY_INSERTMODE, insertMode);
//Begin the Transaction
fm=getChildFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.add(R.id.fccr_rootLayout, fCrE, FragmentCriteriaEdit.sTag);
ft.add(R.id.fccr_rootLayout, fCrL, FragmentCriteriaList.sTag);
ft.commit();
}
@Override
public void onStart() {
super.onStart();
//Get our arguments
Bundle args = getArguments();
if(args!=null){
insertMode=args.getBoolean(CM.BKEY_INSERTMODE);
}
}
@Override
public void onDetach() {
super.onDetach();
try {
Field childFragmentManager = Fragment.class.getDeclaredField("mChildFragmentManager");
childFragmentManager.setAccessible(true);
childFragmentManager.set(this, null);
} catch (NoSuchFieldException e) {
throw new RuntimeException(e);
} catch (IllegalAccessException e) {
throw new RuntimeException(e);
}
}
}
自定义NavigationDrawer适配器：
public class ClassEditDrawerAdapter extends ArrayAdapter<ClassEditDrawerItem>{
Context ctx;
List<ClassEditDrawerItem> itemList;
int layoutResID;
public ClassEditDrawerAdapter(Context context, int layoutResourceID, List<ClassEditDrawerItem> items){
super(context, layoutResourceID, items);
ctx=context;
layoutResID=layoutResourceID;
itemList=items;
}
//An Effective ViewHolder, but for this Array!
private class DrawerItemHolderThing{
TextView itemName;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
DrawerItemHolderThing bobSagget;
View v = convertView;
if(v==null){
Log.d("adapter", "v was null");
LayoutInflater inflater = ((Activity) ctx).getLayoutInflater();
bobSagget= new DrawerItemHolderThing();
v=inflater.inflate(layoutResID, null);
bobSagget.itemName=((TextView) v.findViewById(R.id.item_navbar_title));
v.setTag(bobSagget);
} else {
bobSagget = (DrawerItemHolderThing) v.getTag();
}
ClassEditDrawerItem drawerItem = (ClassEditDrawerItem) this.itemList.get(position);
if(bobSagget.itemName==null){Log.e("Adapter", "no TextView");}
bobSagget.itemName.setText(drawerItem.getItemName());
return v;
}
}
答案 0 :(得分：0)
在第一个自动膨胀的片段中，不应该引用父ViewGroup。在这种情况下，错误位于下面片段的onCreateView部分
//=====================ACTIVITY LIFECYCLE==============================
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.frag_container_criteria, container, false);
return v;
}
应将inflater更改为：
View v = inflater.inflate(R.layout.frag_container_criteria, null, false);
注意容器的null参数。现在，当我尝试从NavigationDrawer中扩充它时，由于我们传递了null，因此View尚未注册到父级。