java.lang.IllegalStateException：指定的子项已经有父项。您必须先调用子视图的父视图上的removeView（）

Question

我正在使用horizo​​ntalscrollview水平滑动屏幕，我想在当前视图上动态地添加视图，但它没有发生，我在代码中做了什么错误..这是我的代码

public class MainActivity extends Activity implements OnGestureListener { 

     private GestureDetector gDetector; 
      private MyHorizontalScrollView scrollView; 
      private View app; 

      @TargetApi(11)  
      @Override 
      public void onCreate(Bundle savedInstanceState) { 
       super.onCreate(savedInstanceState); 

       LayoutInflater inflater = LayoutInflater.from(this); 
       setContentView(inflater.inflate(R.layout.sample, null)); 
//here I edited.. 
    scrollView = (MyHorizontalScrollView) findViewById(R.id.myScrollView_); 
       LinearLayout layout = new LinearLayout(this); 
       scrollView.addView(layout); 

       ListView listView = new ListView(this); 
       initListView(this, listView, "Item ", 30, android.R.layout.simple_list_item_1); 
       layout.addView(listView); 

       //setContentView(R.layout.sample); 
       if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB){ 
        getActionBar().hide(); 
       } 
       findViewById(R.id.sample_button).setOnClickListener(
         new View.OnClickListener() { 
          @Override 
          public void onClick(View v) { 
           int width = (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 40, getResources().getDisplayMetrics()); 
           SlideoutActivity.prepare(MainActivity.this, R.id.inner_content, width); 
           startActivity(new Intent(MainActivity.this, 
             MenuActivity.class)); 
           overridePendingTransition(0, 0); 
          } 
         }); 
       gDetector = new GestureDetector(this); 
      } 
      public static void initListView(Context context, ListView listView,String prefix, int numItems, int layout){ 

       // By using setAdpater method in listview we an add string array in list. 
       String[] arr = new String[numItems]; 
       for(int i = 0; i< arr.length; i++){ 

        arr[i] = prefix + (i +1); 
       } 

       listView.setAdapter(new ArrayAdapter<String>(context, layout, arr)); 
       listView.setOnItemClickListener(new OnItemClickListener() { 

        @Override 
        public void onItemClick(AdapterView<?> parent, View view, int position, 
          long id) { 
         Context context = view.getContext(); 

         String msg = "item[" + position + "]= " + parent.getItemIdAtPosition(position); 

         Toast.makeText(context, msg, 1000).show(); 
         System.out.println(msg); 

        } 
       }); 
      } 
      @Override 
      public boolean onDown(MotionEvent arg0) { 
       // TODO Auto-generated method stub 
       return false; 
      } 

      @Override 
      public boolean onFling(MotionEvent start, MotionEvent finish, float xVelocity, 
        float yVelocity) { 
       if(start.getRawX() < finish.getRawX()){ 

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

        LayoutInflater inflater = LayoutInflater.from(this); 

        scrollView = (MyHorizontalScrollView) findViewById(R.id.myScrollView_); 
        app = inflater.inflate(R.layout.horz_scroll_app, null); 

        ListView listView = (ListView) app.findViewById(R.id.list); 
        initListView(this, listView, "Item ", 30, android.R.layout.simple_list_item_1); 
        setContentView(listView);*/ 

        TextView toolbartext = (TextView)findViewById(R.id.text); 
        toolbartext.setText("New text for samples from left to right"); 
        Toast.makeText(getApplicationContext(), "from left to right Swipe working", Toast.LENGTH_LONG).show(); 
       }else{ 
        TextView toolbartext = (TextView)findViewById(R.id.text); 
        toolbartext.setText("New text for samples from right to left"); 
        Toast.makeText(getApplicationContext(), "from right to left Swipe working", Toast.LENGTH_LONG).show(); 
       } 
       return true; 
      } 

      @Override 
      public void onLongPress(MotionEvent arg0) { 
       // TODO Auto-generated method stub 

      } 

      @Override 
      public boolean onScroll(MotionEvent arg0, MotionEvent arg1, float arg2, 
        float arg3) { 
       // TODO Auto-generated method stub 
       return false; 
      } 

      @Override 
      public void onShowPress(MotionEvent arg0) { 
       // TODO Auto-generated method stub 

      } 

      @Override 
      public boolean onSingleTapUp(MotionEvent arg0) { 
       // TODO Auto-generated method stub 
       return false; 
      } 

      @Override 
      public boolean onTouchEvent(MotionEvent event) { 
       // TODO Auto-generated method stub 
       return gDetector.onTouchEvent(event); 
      } 
     } 

她是我的logcat的内容..

03-29 11:00:22.732: E/AndroidRuntime(303): FATAL EXCEPTION: main 
03-29 11:00:22.732: E/AndroidRuntime(303): java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first. 
03-29 11:00:22.732: E/AndroidRuntime(303): at android.view.ViewGroup.addViewInner(ViewGroup.java:1970) 
03-29 11:00:22.732: E/AndroidRuntime(303): at android.view.ViewGroup.addView(ViewGroup.java:1865) 
03-29 11:00:22.732: E/AndroidRuntime(303): at android.view.ViewGroup.addView(ViewGroup.java:1845) 
03-29 11:00:22.732: E/AndroidRuntime(303): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:217) 
03-29 11:00:22.732: E/AndroidRuntime(303): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:207) 
03-29 11:00:22.732: E/AndroidRuntime(303): at android.app.Activity.setContentView(Activity.java:1658) 
03-29 11:00:22.732: E/AndroidRuntime(303): at com.example.sample.MainActivity.onFling(MainActivity.java:105) 
03-29 11:00:22.732: E/AndroidRuntime(303): at android.view.GestureDetector.onTouchEvent(GestureDetector.java:568) 
03-29 11:00:22.732: E/AndroidRuntime(303): at com.example.sample.MainActivity.onTouchEvent(MainActivity.java:146) 
03-29 11:00:22.732: E/AndroidRuntime(303): at android.app.Activity.dispatchTouchEvent(Activity.java:2089) 
03-29 11:00:22.732: E/AndroidRuntime(303): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1655) 
03-29 11:00:22.732: E/AndroidRuntime(303): at android.view.ViewRoot.handleMessage(ViewRoot.java:1785) 
03-29 11:00:22.732: E/AndroidRuntime(303): at android.os.Handler.dispatchMessage(Handler.java:99) 
03-29 11:00:22.732: E/AndroidRuntime(303): at android.os.Looper.loop(Looper.java:123) 
03-29 11:00:22.732: E/AndroidRuntime(303): at android.app.ActivityThread.main(ActivityThread.java:4627) 
03-29 11:00:22.732: E/AndroidRuntime(303): at java.lang.reflect.Method.invokeNative(Native Method) 
03-29 11:00:22.732: E/AndroidRuntime(303): at java.lang.reflect.Method.invoke(Method.java:521) 
03-29 11:00:22.732: E/AndroidRuntime(303): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868) 
03-29 11:00:22.732: E/AndroidRuntime(303): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626) 
03-29 11:00:22.732: E/AndroidRuntime(303): at dalvik.system.NativeStart.main(Native Method) 

Answer 1

我认为你试图addViews到HorizontalScrollView。

A ScrollView只能有一个孩子。

因此，您可以先将Linear/RelativeLayout添加到ScrollView，然后将其他views添加到此layout。

代码：

像这样的事情

HorizontalScrollView hsv = findViewById(R.id.mHSV); 
//add a linear layout to your scrollview 
LinearLayout layout = new LinearLayout (this); 
hsv.addView(layout); 
//add the remaining views to this linear layout 
TextView textView = new TextView(this); 
layout.addView(textView);