avengers

package com.example.ucvle.app70518; import android.content.Context; import android.content.Intent; import android.content.SharedPreferences; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.text.TextUtils; import android.view.View; import android.widget.EditText; import android.widget.TextView; import android.widget.Toast; public class MainActivity extends AppCompatActivity { EditText edtn1,edtn2,edtn3; TextView result; SharedPreferences pref; String prefe,msj; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); edtn1=(EditText)findViewById(R.id.edtN1); edtn2=(EditText)findViewById(R.id.edtN2); edtn3=(EditText)findViewById(R.id.edtN3); result=(TextView)findViewById(R.id.lblResultado); pref=getSharedPreferences("Preferencias",this.MODE_PRIVATE); prefe=pref.getString("promedio","null"); msj=pref.getString("mensaje","NO HAY REGISTRO"); if(prefe=="null") { result.setText(msj); } else { result.setText(msj+" PROM:"+prefe); } } public void Procesar(View view) { double n1,n2,n3,prom; String msj="",promedio=""; if(!TextUtils.isEmpty(edtn1.getText()) && !TextUtils.isEmpty(edtn2.getText()) && !TextUtils.isEmpty(edtn3.getText())) { n1 = Double.parseDouble(edtn1.getText().toString()); n2 = Double.parseDouble(edtn2.getText().toString()); n3 = Double.parseDouble(edtn3.getText().toString()); prom = (n1 + n2 + n3) / 3; if(prom>=0 && prom=10) { msj+="APROBADO"; } else { msj += "DESAPROBADO"; } promedio=String.format("%.2f",prom); SharedPreferences.Editor editor=pref.edit(); editor.putString("promedio",promedio); editor.putString("mensaje",msj); editor.commit(); result.setText(msj+" PROM:"+promedio); limpiar(); Intent miintent =new Intent(getApplicationContext(),MainActivity.class); miintent.putExtra("supreferencia","promedio"); } else { Toast.makeText(this,"RANGO DE 0-20",Toast.LENGTH_SHORT).show(); limpiar(); } } else { Toast.makeText(this,"Faltan Datos",Toast.LENGTH_SHORT).show(); } } private void limpiar() { edtn1.setText(""); edtn2.setText(""); edtn3.setText(""); } } package com.example.ucvle.app70518; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; public class Main2Activity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main2); } }