CursorLoader是否使Intents停止工作？

FAB的onClickListener内部的Intent在实施LoaderManager.LoaderCallbacks<Cursor>及其方法后使应用崩溃，但在实施这些方法之前，应用工作得很好。为什么onCreateLoader，onLoadFinished和onLoaderReset方法会使FAB停止工作？CursorLoader是否使Intents停止工作？

注意：并非该应用程序的所有功能目前都在运行，即：删除我仍在使用更新方法。

//The intent in the CatalogActivity "The main activity"  
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab); 
     fab.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View view) { 
       Intent newIntent = new Intent(CatalogActivity.this, EditorActivity.class); 
       startActivity(newIntent); 
      } 



//After implementing these methods the EditorActivity, the FAB in the first activity makes the app crash 
    @Override 
    public Loader<Cursor> onCreateLoader(int id, Bundle args) { 
     String[] projection = { 
       PetEntry._ID, 
       PetEntry.COLUMN_PET_NAME, 
       PetEntry.COLUMN_PET_BREED, 
       PetEntry.COLUMN_PET_GENDER, 
       PetEntry.COLUMN_PET_WEIGHT 
     }; 

     return new CursorLoader(this, mCurrentPetUri, projection, null, null, null); 
    } 

    @Override 
    public void onLoadFinished(Loader<Cursor> loader, Cursor data) { 

     if (data == null || data.getCount() < 1) { 
      return; 
     } 

     if (data.moveToNext()) { 
      String name = data.getString(data.getColumnIndex(PetEntry.COLUMN_PET_NAME)); 
      mNameEditText.setText(name); 

      String breed = data.getString(data.getColumnIndex(PetEntry.COLUMN_PET_BREED)); 
      mBreedEditText.setText(breed); 

      int weight = data.getInt(data.getColumnIndex(PetEntry.COLUMN_PET_WEIGHT)); 
      mWeightEditText.setText(Integer.toString(weight)); 

      int gender = data.getInt(data.getColumnIndex(PetEntry.COLUMN_PET_GENDER)); 

      if (gender == PetEntry.GENDER_MALE){ 
       mGenderSpinner.setSelection(1); 
      } else if (gender == PetEntry.GENDER_FEMALE) { 
       mGenderSpinner.setSelection(2); 
      } else { 
       mGenderSpinner.setSelection(0); 
      } 

     } 

    } 



    @Override 
    public void onLoaderReset(Loader<Cursor> loader) { 
     mNameEditText.setText(""); 
     mBreedEditText.setText(""); 
     mWeightEditText.setText(""); 
     mGenderSpinner.setSelection(0); 
    }

来源

2017-04-24 Yahia Hassan

请不要只需链接到您的代码异地。您需要在问题本身中包含[mcve]，以及崩溃中的堆栈跟踪。 –

将编辑该问题 –

的问题是，我初始化loader当URI为null

//The old code 
Intent intent = getIntent(); 

mCurrentPetUri = intent.getData(); 

     if (mCurrentPetUri == null) { 
      setTitle(getString(R.string.editor_activity_title_new_pet)); 

     } else { 
      setTitle(getString(R.string.editor_activity_title_edit_pet)); 
     } 
getLoaderManager().initLoader(1, null, this);

但是我应该初始化loader只有URI不为空

//The new code 
Intent intent = getIntent(); 

     mCurrentPetUri = intent.getData(); 

     if (mCurrentPetUri == null) { 
      setTitle(getString(R.string.editor_activity_title_new_pet)); 

     } else { 
      setTitle(getString(R.string.editor_activity_title_edit_pet)); 
      getLoaderManager().initLoader(1, null, this); 
     }

来源

2017-04-24 12:51:22

CursorLoader是否使Intents停止工作？

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