ERROR: java.lang.NumberFormatException in tp Rechner App

Question

Mein Java-Programm ist:

package slidingmenu.androidhive.info.myapplication; 

import android.os.Bundle; 
import android.app.Activity; 
import android.view.Menu; 
import android.view.View; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.TextView; 

public class MainActivity extends Activity { 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 
     final EditText amt = (EditText) findViewById(R.id.bill_amt); 
     final EditText tip = (EditText) findViewById(R.id.bill_per); 
     final TextView result = (TextView) findViewById(R.id.res); 

     Button calc = (Button) findViewById(R.id.button1); 
     calc.setOnClickListener(new View.OnClickListener() { 

      @Override 
      public void onClick(View v) { 
       // TODO Auto-generated method stub 
       double amount = Double.parseDouble(amt.toString()); 
       double tip_per = Double.parseDouble(tip.toString()); 
       double tip_cal = (amount/tip_per); 
       result.setText("Result : " + Double.toString(tip_cal)); 
      } 
     }); 
    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     // Inflate the menu; this adds items to the action bar if it is present. 
     getMenuInflater().inflate(R.menu.menu_main, menu); 
     return true; 
    } 
} 

und meine logcat ist:

04-12 19:27:24.372 1203-  1203/slidingmenu.androidhive.info.myapplication 
E/AndroidRuntime: FATAL EXCEPTION: main 
java.lang.NumberFormatException: Invalid double: "android.widget.EditText{5320176c VFED..CL ........ 32,257-736,336 #7f0c006d app:id/bill_amt}" 

Wie kann ich diese error..Thanks im Voraus lösen.

Answer 1

Eine Vermutung, aber Sie können nicht die richtige Methode für das richtige Objekt implementieren. Vielleicht, da amt Variable vom Typ TextEdit ist, versuchen Sie es zu ändern:

Double.parseDouble(amt.getText().toString()); 
Double.parseDouble(tip.getText().toString()); 

Lassen Sie mich wissen, wenn dies hilft.