如何为微调器设置“提示文本”？

数据库中的微调器的值。 我很困惑为Spinner添加提示，我在SO中关注了一些post，但我对这个地方很震惊，我试过这个

Spinner sp = (Spinner)findViewById(R.id.spinner); sp.setSelection(pos); 

该位置具有整数值，所以我将其作为位置的整数值，我也尝试使用setSeletction（）方法中的getCount（）

main.java

  //spinner for customer sp=(Spinner)findViewById(R.id.spinner); adapter=new ArrayAdapter(this,R.layout.spinner_layout,R.id.txt,listItems); sp.setAdapter(adapter); public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.sales_order); cus_name = (Spinner) findViewById(R.id.spinner);//customer spinner // Permission StrictMode if (android.os.Build.VERSION.SDK_INT > 9) { StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build(); StrictMode.setThreadPolicy(policy); } //spinner for customer sp=(Spinner)findViewById(R.id.spinner); adapter=new ArrayAdapter(this,R.layout.spinner_layout,R.id.txt,listItems); sp.setAdapter(adapter); } private class BackTask extends AsyncTask { ArrayList list; protected void onPreExecute(){ super.onPreExecute(); list=new ArrayList(); } protected Void doInBackground(Void...params){ InputStream is=null; String result=""; try{ HttpClient httpclient=new DefaultHttpClient(); HttpPost httppost= new HttpPost("http://IP/web_services/customer_spinner.php"); HttpResponse response=httpclient.execute(httppost); HttpEntity entity = response.getEntity(); // Get our response as a String. is = entity.getContent(); }catch(IOException e){ e.printStackTrace(); } //convert response to string try{ BufferedReader reader = new BufferedReader(new InputStreamReader(is,"utf-8")); String line = null; while ((line = reader.readLine()) != null) { result+=line; } is.close(); //result=sb.toString(); }catch(Exception e){ e.printStackTrace(); } // parse json data try{ JSONObject object = new JSONObject(result); JSONArray jArray = object.getJSONArray("cus_Name"); //JSONArray jArray =new JSONArray(result); for(int i=0;i<jArray.length();i++){ JSONObject jsonObject=jArray.getJSONObject(i); // add interviewee name to arraylist list.add(jsonObject.getString("cus_Name")); } } catch(JSONException e){ e.printStackTrace(); } return null; } protected void onPostExecute(Void result){ listItems.addAll(list); adapter.notifyDataSetChanged(); } } 

Answer 1

有很多方法：

1.） Android Hint Spinner

在build.gradle文件中使用此依赖项。

 dependencies { compile 'me.srodrigo:androidhintspinner:1.0.0' } 

输出：

有关更多详细信息，请访问： https ： //github.com/srodrigo/Android-Hint-Spinner

2.）第二种方式

访问这里： https ： //github.com/ravivyas84/AndroidSpinnerHint