简单存储—— Shared Preferences 26 Caoverrie 27 public void on Start super on Start(; loadSharedPreferenceso 30 @override 32. public void on Stop(t Stop save SharedPreferenceso 36 37. private void loadSharedPreferencesoi 38 SharedPreferences sharedPreferences 3o getSharedPreferences(PREFERENCE NAME, MODE) String name= sharedPreferences get String("Name","Tom") 40. int age =sharedPreferences getint("Age", 20); float height= sharedPreferences getFloat("Height",)
25. 26. @Override 27. public void onStart(){ 28. super.onStart(); 29. loadSharedPreferences(); 30. } 31. @Override 32. public void onStop(){ 33. super.onStop(); 34. saveSharedPreferences(); 35. } 36. 37. private void loadSharedPreferences(){ 38. SharedPreferences sharedPreferences = getSharedPreferences(PREFERENCE_NAME, MODE); 39. String name = sharedPreferences.getString("Name","Tom"); 40. int age = sharedPreferences.getInt("Age", 20); 41. float height = sharedPreferences.getFloat("Height",); 简单存储——SharedPreferences
简单存储—— Shared Preferences 43 name Text. setText(name); 44 age Text set Text( String valueOf(age) 45 height Text set Text(String valueOf(height) 46 48. private void save SharedPreferencesot 49 SharedPreferences sharedPreferences getSharedPreferences(PREFERENCE NAME, mOde) 50 SharedPreferences Editor editor sharedPreferences edito 51 editor putString ("Name", name Text. get Texto toString) editor. putInt("Age", Integer parseInt( age Text. get Texto toString)) editor. put Float("Height Float parse Float(height Text. get Texto toString)) editor.commito 56
42. 43. nameText.setText(name); 44. ageText.setText(String.valueOf(age)); 45. heightText.setText(String.valueOf(height)); 46. } 47. 48. private void saveSharedPreferences(){ 49. SharedPreferences sharedPreferences = getSharedPreferences(PREFERENCE_NAME, MODE); 50. SharedPreferences.Editor editor = sharedPreferences.edit(); 51. 52. editor.putString("Name", nameText.getText().toString()); 53. editor.putInt("Age", Integer.parseInt(ageText.getText().toString())); 54. editor.putFloat("Height", Float.parseFloat(heightText.getText().toString())); 55. editor.commit(); 56. } 57. } 简单存储——SharedPreferences
简单存储—— Shared Preferences a示例 Share Preferencedemo 示例将读取 Simple Preference Dem示例保存的信息,并在程序 启动时显示在用户界面上 因9:40AM Share Demo 姓名:Tom 年龄:20 身高:1.81
❑ 示例SharePreferenceDemo ◼ 示例将读取SimplePreferenceDemo示例保存的信息，并在程序 启动时显示在用户界面上 简单存储——SharedPreferences
简单存储—— Shared Preferences 口下面给出 SharePreferenceDemo示例的核心代码 1. public static final String PREFERENCE PACKAGE edu. hrbeu. SimplePreferenceDemo 2. public static final String PREFERENCE NAME="Save Setting 3. public static int MODE =Context MODE WORLD READABLE Context MODE WORLD WRITEABLE 456789 5. public void on Create( Bundle savedInstance State) Context c= null try i 获取 Context c=this. createPackage Context(PREFERENCE PACKAGE Context CONTEXT IGNORE SECURITY) 3 catch(NameNotFoundException e) 10. e.printStackTraceO 12. SharedPreferences sharedPreferences c. getSharedPreferences(PREFERENCE NAME, mOde):
❑ 下面给出SharePreferenceDemo示例的核心代码 1. public static final String PREFERENCE_PACKAGE = "edu.hrbeu.SimplePreferenceDemo"; 2. public static final String PREFERENCE_NAME = "SaveSetting"; 3. public static int MODE = Context.MODE_WORLD_READABLE + Context.MODE_WORLD_WRITEABLE; 4. 5. public void onCreate(Bundle savedInstanceState) { 6. Context c = null; 7. try { 8. c = this.createPackageContext(PREFERENCE_PACKAGE, Context.CONTEXT_IGNORE_SECURITY); 9. } catch (NameNotFoundException e) { 10. e.printStackTrace(); 11. } 12. SharedPreferences sharedPreferences = c.getSharedPreferences(PREFERENCE_NAME, MODE); 简单存储——SharedPreferences 获取Context
简单存储—— Shared Preferences String name= sharedPreferences get String("Name", Tom") 3456 int age = sharedPreferences getInt("Age", 20); float height= sharedPreferences get Float("Height") 第8行代码调用了 createPackage Context(取到了 SimplePreference Demo示例的 Context 第8行代码第1个参数是 Simple Preference Demo的包名称 ,在代码第1行进行了定义 第2个参数 Context conteXt GNore SEcurit表示 忽略所有可能产生的安全问题。这段代码可能引发异常, 因此必须防止在 try/catch中
◼ 第8行代码调用了createPackageContext()获取到了 SimplePreferenceDemo示例的Context ◼ 第8行代码第1个参数是SimplePreferenceDemo的包名称 ，在代码第1行进行了定义 ◼ 第2个参数Context.CONTEXT_IGNORE_SECURIT表示 忽略所有可能产生的安全问题。这段代码可能引发异常， 因此必须防止在try/catch中 13. String name = sharedPreferences.getString("Name","Tom"); 14. int age = sharedPreferences.getInt("Age", 20); 15. float height = sharedPreferences.getFloat("Height",); 16. } 简单存储——SharedPreferences