FileOutputStream을 사용하여 간단한 프로그램을 실행하려고합니다. 이 프로그램을 실행하면 응용 프로그램이 "Application stoppped an unfortunately"라는 메시지를 표시합니다. Logcat에 NullPointerException이 표시됩니다. 내 코드에 무슨 문제가 있습니까 ??FileOutputStream의 Null 포인터 예외
package com.example.storageinternal;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
public class MainActivity extends Activity {
private EditText editname,editemail;
private Button save;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
editname = (EditText)findViewById(R.id.editname);
editemail = (EditText)findViewById(R.id.editemail);
save.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v)
// TODO Auto-generated method stub
String namestring = editname.getText().toString();
String emailstring = editemail.getText().toString();
FileOutputStream fos = null;
try {
fos = openFileOutput("Mystorage",Context.MODE_PRIVATE);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
fos.write(namestring.getBytes());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
fos.write(emailstring.getBytes());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally {
if (fos != null) {
try {
fos.close();
}
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
});
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
'save = (Button) findViewById (R.id.yoursavebtn);' – Mobi