关于oncreate：Android：在应用关闭时保存实例状态

Android: Save an instance state when app is closed

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Possible Duplicate:
How do I save an Android application's state?

我是Java和Android的新手，需要学习一些小项目。我制作了一个货币追踪应用程序，允许用户输入值，然后继续减去它。一切正常，但我希望在应用程序关闭并重新打开时保存或缓存这些值。阅读时，我发现也许暂停一下就可以了，但仍然不能100%理解。

有人能推荐如何做以及如何应用到我的代码吗？

非常感谢你的帮助！！

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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 +"
" + tracker.getText().toString());

}
}
});
}
}

请使用SharedPreferences将数据存储在专用应用程序存储中。在onpause方法中实现SharedPrefernces，如下：

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@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();
}