AndroidDev：股票应用程序的AsyncTask - 什么都没有发生

Question

我正在研究一个简单的应用程序来收集股票的当前信息。我正在应用AsyncTask，并且我已经构建了我的GUI，但是在我的EditText中输入股票代码后，似乎没有发生任何事情。任何援助非常感谢。我试着用Google搜索这些主题，看看文档和教程，但不知道我缺少什么。我约2个月学习Android开发。

这里是我的代码：

package cornez.com.stockquotes; 

import android.content.Context; 
import android.graphics.Bitmap; 
import android.os.AsyncTask; 
import android.support.v7.app.AppCompatActivity; 
import android.os.Bundle; 
import android.view.KeyEvent; 
import android.view.WindowManager; 
import android.view.inputmethod.EditorInfo; 
import android.view.inputmethod.InputMethodManager; 
import android.widget.EditText; 
import android.widget.TextView; 

import java.io.IOException; 

public class MainActivity extends AppCompatActivity { 

    EditText editText; 
    String symbol; 
    TextView symbolText; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 

     TextView nameText, tradePriceText, tradeTimeText, changeText, rangeText; 

     symbolText = (TextView) findViewById(R.id.symbolText); 
     nameText = (TextView) findViewById(R.id.nameText); 
     tradePriceText = (TextView) findViewById(R.id.tradePriceText); 
     tradeTimeText = (TextView) findViewById(R.id.tradeTimeText); 
     changeText= (TextView) findViewById(R.id.changeText); 
     rangeText = (TextView) findViewById(R.id.rangeText); 


     editText = (EditText) findViewById(R.id.editText); 
     editText.setOnEditorActionListener(new TextView.OnEditorActionListener() 
     { 
      @Override 
      public boolean onEditorAction(TextView v, int actionId, 
              KeyEvent event) 
      { 
       if (actionId == EditorInfo.IME_ACTION_DONE) 
       { 
        // actions when "Done" key is pressed 

        InputMethodManager imm = (InputMethodManager)v.getContext().getSystemService(Context.INPUT_METHOD_SERVICE); 
        imm.hideSoftInputFromWindow(v.getWindowToken(), 0); 
        return true; 

       } 
       return false; 
      } 
     }); 



     editText.requestFocus(); 
     getWindow().setSoftInputMode(WindowManager.LayoutParams. 
       SOFT_INPUT_STATE_VISIBLE); 

     getStockInfoTask stockTask = new getStockInfoTask(); 
     symbol = editText.getText().toString(); 
     stockTask.execute(symbol); 


    } 

    //AsyncTask 
    private class getStockInfoTask extends AsyncTask<String, Void, Stock> 
    { 

     protected Stock doInBackground(String... params) 
     { 
      Stock stock = new Stock(symbol); 
      try { 
       stock.load(); 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } 

      return stock; 
     } 

     protected void onPostExecute(Stock stock) 
     { 
      symbolText.setText(stock.getSymbol()); 
     } 
    } 



} 

Answer 1

1. 里面的代码

   onEditorAction 
   

运行在一个新的线程时TextView的接收动作。

代码

symbol = editText.getText().toString(); 

听者被初始化后运行同步。

所以：

editText.setOnEditorActionListener(new TextView.OnEditorActionListener() 
    { 
     @Override 
     public boolean onEditorAction(TextView v, int actionId, 
             KeyEvent event) 
     { 
      if (actionId == EditorInfo.IME_ACTION_DONE) 
      { 
       // actions when "Done" key is pressed 

       InputMethodManager imm = (InputMethodManager)v.getContext().getSystemService(Context.INPUT_METHOD_SERVICE); 
       imm.hideSoftInputFromWindow(v.getWindowToken(), 0); 

       getStockInfoTask stockTask = new getStockInfoTask(); 
       symbol = editText.getText().toString(); 
       stockTask.execute(symbol); 

       return true; 
      } 
      return false; 
     } 
    }); 



    editText.requestFocus(); 
    getWindow().setSoftInputMode(WindowManager.LayoutParams. 
      SOFT_INPUT_STATE_VISIBLE);