Android的viewBinder上simpleCursorAdapter显示图像 [英] Android viewBinder displaying images on simpleCursorAdapter

问题描述

我创建了一个工作ViewBinder我simpleCursorAdapter使用，一切都正常。所需要的图像显示为他们应该，等等。但是，当我在测试我的code，我把我的日志我的viewbinder显示的标准显示图像。当我看到logcat的，它显示如下图所示的结果两次迭代。 （只有五个条目）。这又将创造我的if语句和生成的图像显示的两次迭代。这不是显示器的问题，但它会创建一些冗余的，因为它会显示在ListView图像的两倍。

I have created a working ViewBinder to use with my simpleCursorAdapter, and all is functioning properly. The desired images display as they should,etc. But when I was testing my code, I put a log my in my viewbinder that displays the criteria for displaying the image. When I look at logCat, it shows two iterations of the results as shown below. (there are only five entries). Which would in turn create two iterations of my if statements and resulting image display. This isn't a problem with the display, but it would create some redundancy in that it would display the images in the listView twice.

日志文件：

columnIndex=1  categoryIdentifier = Supplier
columnIndex=1  categoryIdentifier = Customer
columnIndex=1  categoryIdentifier = Other
columnIndex=1  categoryIdentifier = Other
columnIndex=1  categoryIdentifier = Other
columnIndex=1  categoryIdentifier = Supplier
columnIndex=1  categoryIdentifier = Customer
columnIndex=1  categoryIdentifier = Other
columnIndex=1  categoryIdentifier = Other
columnIndex=1  categoryIdentifier = Other

在code运行viewBinder是这样的：

The code to run the viewBinder is this:

code：

private void fillData() {

    //The desired columns to be bound: 
    String[] from = new String[] { ContactsDB.COLUMN_CATEGORY, ContactsDB.COLUMN_LAST_NAME, ContactsDB.COLUMN_FIRST_NAME };
    //The XML views that the data will be bound to:
      int[] to = new int[] {R.id.contact_icon, R.id.label2, R.id.label};

   getLoaderManager().initLoader(0, null, this);
   adapter = new SimpleCursorAdapter(this, R.layout.contact_row, null, from, to, 0);
   // Set the ViewBinder to alternate the image in the listView
   adapter.setViewBinder(new SimpleCursorAdapter.ViewBinder() {
       public boolean setViewValue(View view, Cursor cursor, int columnIndex) {         
          // int viewId = view.getId();
           int categoryIndex = cursor.getColumnIndexOrThrow(ContactsDB.COLUMN_CATEGORY);

           if(columnIndex == categoryIndex)        
           {  
               String categoryIdentifier = cursor.getString(columnIndex);
               //switch categoryIdentifier
              if(categoryIdentifier.equalsIgnoreCase("Supplier")){
                  displayImage = (ImageView) view;
                  displayImage.setImageResource(R.drawable.supplier);
              }
              if(categoryIdentifier.equalsIgnoreCase("Other")){
                  displayImage = (ImageView) view;
                  displayImage.setImageResource(R.drawable.other);
              }    
               Log.v("TEST COMPARISON", "columnIndex=" + columnIndex + "  categoryIdentifier = " + categoryIdentifier);  

             return true;          
         } 
         return false;      
         } 
       });

    setListAdapter(adapter);
  } // end of fillData

  // Sort the names by last name, then by first name
  String orderBy = ContactsDB.COLUMN_LAST_NAME + " COLLATE NOCASE ASC"
  + "," + ContactsDB.COLUMN_FIRST_NAME + " COLLATE NOCASE ASC" ;

  // Creates a new loader after the initLoader () call
  @Override
  public Loader<Cursor> onCreateLoader(int id, Bundle args) {
    //String[] projection = { ContactsDB.ROW_ID, ContactsDB.COLUMN_LAST_NAME, ContactsDB.COLUMN_FIRST_NAME };
      String[] projection = { ContactsDB.ROW_ID, ContactsDB.COLUMN_CATEGORY, ContactsDB.COLUMN_LAST_NAME, ContactsDB.COLUMN_FIRST_NAME };
    CursorLoader cursorLoader = new CursorLoader(this,
    whateverContentProvider.CONTENT_URI, projection, null, null, orderBy);
    return cursorLoader;
  }

任何人都知道为什么会有这种冗余？

Anyone know why there would be this redundancy?

推荐答案

改变你的ListView 的android：layout_height 来match_parent

change your listview android:layout_height to match_parent

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