java 将少量信息保存为 android 中的设置（例如第一次运行该应用程序）
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原文地址: http://stackoverflow.com/questions/15385117/
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Save little information as setting in android (like first time that app is run)
提问by Fcoder
I want to save a flag for recognizing that my app is run for the first time or not. For this simple job I don't want to create database..
我想保存一个标志来识别我的应用程序是否第一次运行。对于这个简单的工作，我不想创建数据库..
Is there a simple option to do this? I want to save and read little pieces of information only.
有没有一个简单的选择来做到这一点？我只想保存和阅读少量信息。
回答by Ajay S
Use sharedPreferenceor filesto save the data but better option is sharedPreference.
使用sharedPreference或files来保存数据，但更好的选择是sharedPreference。
For Retrieving
用于检索
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
boolean silent = settings.getBoolean("silentMode", false);
For Saving
为了节省
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = settings.edit();
editor.putBoolean("silentMode", true);
editor.commit();
回答by Rajitha Siriwardena
Use SharedPreferences.
使用SharedPreferences.
SharedPreferences preferences = getSharedPreferences("prefName", MODE_PRIVATE);
SharedPreferences.Editor edit= preferences.edit();
edit.putBoolean("isFirstRun", false);
edit.commit();
回答by Joop
A proper way to do this is by using the Android class SharedPreferenceswhich is used for things like this.
执行此操作的正确方法SharedPreferences是使用用于此类操作的 Android 类。
Storing Settings
存储设置
SharedPreferences settings = getSharedPreferences(NAME_OF_PREFERENCES, MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
editor.putBoolean("appPreviouslyStarted", true);
editor.apply();
Don't forget to apply or your mutations to the settings won't be saved!
不要忘记应用，否则您对设置的更改将不会被保存！
You can create multiple settings by using different NAME_OF_PREFERENCES. The settings are stored on the device so will be available after closing the application.
您可以使用不同的NAME_OF_PREFERENCES. 设置存储在设备上，因此在关闭应用程序后即可使用。
When you try to retrieve NAME_OF_PREFERENCESthat is not already created, you create a new one. See more behavior like this here.
当您尝试检索NAME_OF_PREFERENCES尚未创建的内容时，您会创建一个新内容。在此处查看更多此类行为。
apply() versus commit()
apply() 与 commit()
You can use editor.apply()as well as editor.commit(), the only difference is that apply() does not return a booleanvalue with if the edit was successful or not. editor.apply() is therefor faster and more commonly used.
您可以使用editor.apply()as well editor.commit()，唯一的区别是boolean如果编辑成功与否， apply() 不会返回值。因此 editor.apply() 更快，更常用。
What is MODE_PRIVATE
什么是 MODE_PRIVATE
You can see all about the different modes here. For your case MODE_PRIVATEis fine.
您可以在此处查看有关不同模式的所有信息。因为你的情况MODE_PRIVATE很好。
Retrieving settings
检索设置
SharedPreferences settings = getSharedPreferences(NAME_OF_PREFERENCES, MODE_PRIVATE);
boolean silent = settings.getBoolean("silentMode", false);
When retrieving a settings from a SharedPreferencesobject you always have to specify a default value which will be returned when the setting was not found. In this case that's false.
从SharedPreferences对象中检索设置时，您始终必须指定一个默认值，该值将在未找到该设置时返回。在这种情况下，就是false.
回答by Raynold
I suggest you to go for SharedPreferencepersistent storage. Its very easy and fast storing/retrival for small amount of information.
我建议您使用SharedPreference持久存储。它非常容易和快速地存储/检索少量信息。
See the code to get the value from SharedPreference
查看代码以从 SharedPreference 获取值
// Restore preferences
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
boolean silent = settings.getBoolean("silentMode", false);
setSilent(silent);
and to Store value in SharedPreference
并在 SharedPreference 中存储值
// We need an Editor object to make preference changes.
// All objects are from android.context.Context
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = settings.edit();
editor.putBoolean("silentMode", mSilentMode);
回答by Alex Zaraos
You can do one class for example: (like a object for instance)
例如，您可以执行一个类：（例如一个对象）
import android.content.Context;
import android.content.SharedPreferences;
public class SettingsMain {
Context context;
SharedPreferences preferences;
SharedPreferences.Editor editor;
private static final String PREFER_NAME = "settingsMain";
public static final String KEY_VIBRATE = "switchVibrate";
public SettingsMain(Context context) {
this.context = context;
setPreferences();
}
private void setPreferences(){
preferences = context.getSharedPreferences(PREFER_NAME, context.MODE_PRIVATE);
editor = preferences.edit();
}
public void cleanPreferences(){
editor.clear();
editor.commit();
}
public void setStatusVibrate(Boolean status){
editor.putBoolean(KEY_VIBRATE, status);
editor.commit();
}
public Boolean getstatusVibrate(){
return preferences.getBoolean(KEY_VIBRATE, true);
}
}
On your activity call:
在您的活动电话中：
public class Home extends AppCompatActivity {
private SettingsMain settings;
private SwitchCompat switchVibrate;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.master);
setResources();
getSettings();
}
private void setResources(){
switchVibrate = (SwitchCompat) findViewById(R.id.master_main_body_vibrate_switch);
switchVibrate.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
settings.setStatusVibrate(isChecked);
}
});
}
private void getSettings(){
settings = new SettingsMain(this);
switchVibrate.setChecked(settings.getstatusVibrate());
}
}
回答by Jay Mayu
What about using staticvariables globally?
static全局使用变量怎么样？
You can do this as given in this tutorial. I know handling Content providers are unnecessary just to keep some flags.
您可以按照本教程中的说明执行此操作。我知道处理内容提供程序是不必要的，只是为了保留一些标志。
Else you can check out Shared Preferencesprovided by Android. Here's a good exampleto get started.
否则，您可以查看Android 提供的共享首选项。这是一个很好的入门示例。
This would be my recommendation.
这将是我的建议。
