Android: Save an instance state when app is closed
Possible Duplicate:
How do I save an Android application's state?
I am new to Java and Android and building some small projects to learn. I made a money tracking app which allows the user to input values and it simply continues to subtract it. Everything works fine but I wanted the values to save or cache when the app is closed and reopened. Reading, I found maybe a OnPause would do the trick, but still not 100% understanding it.
Can anyone recommend how to do this and how to apply to my code?
Thank you so much for your help!!
package ps.age.sl;
import java.text.NumberFormat;
import java.util.Locale;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.TextView;
public class MoneyTrackerActivity extends Activity {
/** Called when the activity is first created. */
ImageButton subtract;
EditText startingmoney,submoney, endmoney, tracker;
Locale currentLocale = Locale.getDefault();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// startingmoney = (EditText) findViewById (R.id.firstmoney);
// submoney = (EditText) findViewById (R.id.submoney);
// subtract = (ImageButton) findViewById (R.id.subbutton);
// endmoney = (EditText) findViewById (R.id.endtv);
// tracker = (EditText) findViewById (R.id.trackertv);
startingmoney.setText("");
submoney.setText("");
endmoney.setText("");
subtract.setOnClickListener(new View.OnClickListener() {
double currentValue=0;
double startValue=0;
public void onClick(View v) throws NumberFormatException {
if (v == subtract)
{
NumberFormat currencyFormatter;
currencyFormatter = NumberFormat.getCurrencyInstance(currentLocale);
String totalString;
String x = startingmoney.getText().toString();
String y = submoney.getText().toString ();
double total;
double xm = 0.00;
double ym =0.00;
try
{
xm = Double.parseDouble(x);
}
catch(NumberFormatException n)
{
xm = 0.00;
}
try
{
ym = Double.parseDouble(y);
}
catch(NumberFormatException n)
{
ym = 0.00;
}
if(startValue!=xm){
startValue=xm;
currentValue=xm;
}
currentValue = currentValue -ym;
totalString = currencyFormatter.format(currentValue);
endmoney.setText(totalString);
tracker.setText("you have entered " + totalString +"n" + tracker.getText().toString());
}
}
});
}
}
Please use SharedPreferences
to store the data in Private application Storage. Implementing SharedPrefernces
in onPause method like below :
@Override
protected void onPause()
{
super.onPause();
// Store values between instances here
SharedPreferences preferences = getSharedPreferences("sharedPrefs", 0);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("CLASSLABEL", this.getLocalClassName()); // value to store
editor.putString("STRINGLABEL",String1 );
editor.putString("STRINGLABEL1",String2);
// Commit to storage
editor.commit();
}
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