Android - contentResolver.notifyChange（）放慢性能

Question

我有一個覆蓋bulkInsert()的MyContentProvider類。在此方法中，我使用SQLite事務向數據庫中插入大約4,000行，這在三星Galaxy S4設備上大約需要25秒。

然而，當我除去從我bulkInsert()方法這一行...

getContext().getContentResolver().notifyChange(insertedId, null);

...總插入時間降低到約1或2秒。

那麼，有沒有更好的方法可以撥打notifyChange()？

我曾嘗試調用它在另一個線程，這樣的...

    new Thread(new Runnable() { 
        public void run() { 
         getContext().getContentResolver().notifyChange(insertedId, null); 
        } 
       }).start(); 

...但它仍然緩慢，而由於某種原因，導致一個OutOfMemoryError。

爲了完整起見，這裏是我的bulkInsert()方法...

@Override 
public int bulkInsert(Uri uri, ContentValues[] valuesArray) { 

    /* 
    * Open a read/write database to support the transaction. 
    */ 
    SQLiteDatabase db = dbHelper.getWritableDatabase(); 

    String tableName; 

    switch (uriMatcher.match(uri)) { 
     case BRANDS_SEARCH: 
      tableName = BRAND_NAMES_TABLE; 
      break; 
     case PRODUCTS_SEARCH: 
      tableName = PRODUCTS_TABLE; 
      break; 
     case PARENT_COMPANIES_SEARCH: 
      tableName = PARENT_COMPANIES_TABLE; 
      break; 
     case PRODUCTS_DATA_SEARCH: 
      tableName = PRODUCTS_DATA_TABLE; 
      break; 
     default: 
      //break; 
      throw new IllegalArgumentException("Unsupported URI: " + uri); 
    } 

    /* 
    * Begin the transaction 
    */ 
    db.beginTransaction(); 

    int numSuccessfulInsertions = 0; 

    try { 

     for (int i = 0; i < valuesArray.length; i++) { 

      /* 
      * Insert the values into the table 
      */ 
      long rowId = db.insert(tableName, null, valuesArray[i]); 

      if (rowId > -1) { 

       /* 
       * Increment numSuccessfulInsertions 
       */ 
       numSuccessfulInsertions++; 

       /* 
       * Construct the URI of the newly inserted row. 
       */ 
       Uri insertedId = ContentUris.withAppendedId(uri, rowId); 

       /* 
       * Notify any observers of the change in the data set. 
       */ 
       getContext().getContentResolver().notifyChange(insertedId, null); 



      } 
      else { 

       /* 
       * Don't give up (as not all insert attempts need to succeed) 
       */ 
       //throw new Exception("Could not insert row"); 
      } 

     } 

     /* 
     * Return number of successful insertions 
     */ 
     return numSuccessfulInsertions; 
    } 
    catch(Exception e) { 

     Log.e(LOG_TAG, "bulkInsert exception", e); 

     /* 
     * Return number of successful insertions 
     */ 
     return numSuccessfulInsertions; 

    } 
    finally { 

     /* 
     * Some (or all) insertion attempts succeeded 
     */ 
     db.setTransactionSuccessful(); 

     /* 
     * Always end the transaction 
     */ 
     db.endTransaction(); 
    } 
} 

Answer 1

大頭操作插入每條記錄通知一次，一次也沒有。將您的呼叫轉移到notifyChange，使其跟隨for循環。