使用SimpleAdapter有微调 [英] Using SimpleAdapter with Spinner

问题描述

我是新的Andr​​oid开发。我试图通过使用SimpleAdapter来填充微调。但微调的名单显示空白元素。当我点击任何一个元素，它的文本正确显示在吐司。请告诉我什么是我下面的code中的问题。

 公共无效的onCreate（包savedInstanceState）{

  私人名单，其中，地图＆LT;字符串，字符串＆GT;＆GT;数据=新的ArrayList＆LT;地图＆LT;字符串，字符串＆GT;＆GT;（）;

  的String []从=新的String [] {colorsData};
  INT []到=新INT [] {R.id.spinner};

  。的String []颜色= getResources（）getStringArray（R.array.colorsData）;

  的for（int i = 0; I＆LT; colors.length;我++）{
   data.add（addData（颜色[I]））;
  }

  微调微调=（微调）findViewById（R.id.spinner）;

  SimpleAdapter simpleAdapter =新SimpleAdapter（这一点，数据，android.R.layout.simple_spinner_item，从，到）;
  simpleAdapter.setDropDownViewResource（android.R.layout.simple_spinner_dropdown_item）;
  spinner.setAdapter（simpleAdapter）;

  spinner.setOnItemSelectedListener（新OnItemSelectedListener（）{
   @覆盖
   公共无效onItemSelected（适配器视图＆LT;＆GT;母公司视图中查看，
     INT位置，长的id）{
    Toast.makeText（
      parent.getContext（），
      选定颜色： - 
        + parent.getItemAtPosition（位置），
      Toast.LENGTH_LONG）.show（）;
   }
  }）;
 }

 私人地图＆LT;字符串，字符串＆GT; addData（字符串colorName）{
  地图＆LT;字符串，字符串＆GT; MAPLIST =新的HashMap＆LT;字符串，字符串＆GT;（）;
  mapList.put（colorsData，colorName）;
  返回MAPLIST;
 }
 

解决方案

我是约95％确保您的到数组应该被声明为：

  INT []到=新INT [] {android.R.id.text1};
 

给一个尝试。

---

修改（根据下面的评论）：

好像有哪些原因造成的IllegalStateException异常在旧版本的Andr​​oidOS的错误。 （我没有看到异常的2.2，但我没有看到它在仿真器1.5）的错误可以通过添加ViewBinder到SimpleAdapter被合作周围。 ViewBinder并不难实现;这里有一个例子：

  SimpleAdapter.ViewBinder viewBinder =新SimpleAdapter.ViewBinder（）{

        公共布尔setViewValue（查看视图，对象数据，
                字符串textRe presentation）{
            //我们配置SimpleAdapter创建TextViews（见
            //了'到'数组），所以这个转换应该是安全的：
            TextView中的TextView =（TextView的）观点;
            textView.setText（textRe presentation）;
            返回true;
        }
    };
    simpleAdapter.setViewBinder（viewBinder）;
 

我的博客上讲述这个<一href="http://www.outofwhatbox.com/blog/2010/12/android-spinners-simpleadapter-and-maybe-viewbinder/">here.

I am new to Android development. I am trying to populate a spinner by using the SimpleAdapter. But spinner's list is showing blank element. When I click any element, its text is shown properly in Toast. Please tell me what is the problem in my code below.

 public void onCreate(Bundle savedInstanceState) {

  private List<Map<String, String>> data = new ArrayList<Map<String, String>>();

  String[] from = new String[] { "colorsData" };
  int[] to = new int[] { R.id.spinner };

  String[] colors = getResources().getStringArray(R.array.colorsData);

  for (int i = 0; i < colors.length; i++) {
   data.add(addData(colors[i]));
  }

  Spinner spinner = (Spinner) findViewById(R.id.spinner);

  SimpleAdapter simpleAdapter = new SimpleAdapter(this, data, android.R.layout.simple_spinner_item, from, to);
  simpleAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
  spinner.setAdapter(simpleAdapter);

  spinner.setOnItemSelectedListener(new OnItemSelectedListener() {
   @Override
   public void onItemSelected(AdapterView<?> parent, View view,
     int position, long id) {
    Toast.makeText(
      parent.getContext(),
      "Selected Color:-  "
        + parent.getItemAtPosition(position),
      Toast.LENGTH_LONG).show();
   }
  });
 }

 private Map<String, String> addData(String colorName) {
  Map<String, String> mapList = new HashMap<String, String>();
  mapList.put("colorsData", colorName);
  return mapList;
 }

解决方案

I'm about 95% sure that your to array should be declared as:

  int[] to = new int[] { android.R.id.text1 };

Give that a try.

---

EDIT (based on comments below):

It seems there was a bug in older versions of AndroidOS which caused that IllegalStateException. (I didn't see the exception in 2.2, but I did see it in 1.5 in the emulator.) The bug can be worked around by adding a ViewBinder to the SimpleAdapter. ViewBinder isn't hard to implement; here's an example:

    SimpleAdapter.ViewBinder viewBinder = new SimpleAdapter.ViewBinder() {

        public boolean setViewValue(View view, Object data,
                String textRepresentation) {
            // We configured the SimpleAdapter to create TextViews (see
            // the 'to' array), so this cast should be safe:
            TextView textView = (TextView) view;
            textView.setText(textRepresentation);
            return true;
        }
    };
    simpleAdapter.setViewBinder(viewBinder);

I blogged about this here.

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