我有一个应用程序,它将MainActivity中明星的总收入显示为textview . 如果应用程序第一次运行,我想做的是输入0 . 然后,当我完成一个级别并获得一些星级(如currentScore 50 = newScore)后,它将使用newScore textView重定向到MainActivity .
这是我的MainActivity,textview显示分数
public class MainActivity extends Activity {
private static TextView txt_stars;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
updateStars();
}
public void updateStars() {
SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putInt("Stars", 0);
editor.commit();
txt_stars = (TextView) findViewById(R.id.txtStars);
sharedPreferences = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
//the key is "Stars" don't forget to type it as you created the Sp
String stars = String.valueOf(sharedPreferences.getInt("Stars", 0));
txt_stars.setText(stars);
}
}
对于我阅读当前分数的活动,然后添加50,然后更新
public void onClick(DialogInterface dialog, int whichButton) {
SharedPreferences sharedPreferences =
PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
Integer newstars = sharedPreferences.getInt("Stars", 0);
Integer totalStars = newstars + 50;
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putInt("Stars", totalStars);
editor.commit();
//please help me improve my code here
Intent nextForm = new Intent(.MainActivity");
startActivity(nextForm);
}
还可以在不同的活动中使用SharedPreferences吗?就像我只是从ActivityOne保存一个分数,可以在ActivityTwo中读取?
非常感谢!
2 回答
好吧,你应该首先阅读the SharedPreferences documentation,然后按照我的步骤保存值
SharedPreferences
您的
UpdateStars()
方法应如下所示:每次你想要保持用户
Stars
,你将不得不使用putInt()
:我曾经写过一个有用的SharedPreferences类来轻松编写/检索数据,你可以从这里复制/粘贴:
https://github.com/asystat/bus_locator/blob/master/benasque2014/Autobus/src/com/example/com/benasque2014/mercurio/KeyStoreController.java
然后你这样写:
yourValue可以是int,boolean,long或string
并检索:
您还可以在MainApplication或Launcher Activity的onCreate方法中调用KeyStoreController.getKeyStore() . appOpened(),然后您可以将getTimesOpened()和isFirstLaunch()用于您要添加到应用程序的任何功能 .
我希望它对某人有用 .