Obtenir la valeur entière de edittext

Lorsque j'essaie d'exécuter le code ci-dessous, mon programme s'arrête. Je veux que ce code pour obtenir la valeur de edittext mais sa ne fonctionne pas comme je m'y attendais. Ce que je fais mal?

public class MainActivity extends Activity {

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

    Button sum = (Button) findViewById(R.id.button1);
    Button cancel = (Button) findViewById(R.id.button2);

    final EditText from = (EditText) findViewById(R.id.editText1);
    final EditText upto = (EditText) findViewById(R.id.editText2);
    final EditText runsum = (EditText) findViewById(R.id.editText3);

    final int f = Integer.parseInt(from.getText().toString());
    final int u = Integer.parseInt(upto.getText().toString());

}

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
}

Voici mon LogCat désolé pour le désordre :/

08-28 19:34:44.241: E/Trace(3346): error opening trace file: No such file or directory (2)
08-28 19:34:44.780: D/AndroidRuntime(3346): Shutting down VM
08-28 19:34:44.780: W/dalvikvm(3346): threadid=1: thread exiting with uncaught exception(group=0x40a13300)
08-28 19:34:44.790: E/AndroidRuntime(3346): FATAL EXCEPTION: main
08-28 19:34:44.790: E/AndroidRuntime(3346): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.project/com.example.project.MainActivity}: java.lang.NumberFormatException: Invalid int: ""
08-28 19:34:44.790: E/AndroidRuntime(3346):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at android.app.ActivityThread.access$600(ActivityThread.java:130)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at android.os.Handler.dispatchMessage(Handler.java:99)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at android.os.Looper.loop(Looper.java:137)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at android.app.ActivityThread.main(ActivityThread.java:4745)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at java.lang.reflect.Method.invokeNative(Native Method)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at java.lang.reflect.Method.invoke(Method.java:511)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at dalvik.system.NativeStart.main(Native Method)
08-28 19:34:44.790: E/AndroidRuntime(3346): Caused by: java.lang.NumberFormatException: Invalid int: ""
08-28 19:34:44.790: E/AndroidRuntime(3346):     at java.lang.Integer.invalidInt(Integer.java:138)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at java.lang.Integer.parseInt(Integer.java:359)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at java.lang.Integer.parseInt(Integer.java:332)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at com.example.project.MainActivity.onCreate(MainActivity.java:25)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at android.app.Activity.performCreate(Activity.java:5008)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
08-28 19:34:44.790: E/AndroidRuntime(3346):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)
08-28 19:34:44.790: E/AndroidRuntime(3346):     ... 11 more
08-28 19:35:10.560: E/Trace(3394): error opening trace file: No such file or directory (2)
08-28 19:35:11.629: D/gralloc_goldfish(3394): Emulator without GPU emulation detected.
08-28 19:48:19.295: I/Choreographer(3394): Skipped 41 frames!  The application may be doing too much work on its main thread.
  • est-il de lancer une erreur, qu'est-ce à dire que "je ne pouvais pas le faire"? Si vous rencontrez des erreurs, vous devez poster votre logcat
  • Où êtes-vous essayer d'obtenir de l'editText à partir de? De quel type d'objet est R? il semble beaucoup d'autres codes ou atleast quelques explenations sont manquants.
InformationsquelleAutor theduman | 2012-10-14