如何從android中其他應用的其他應用的共享偏好中獲取價值？

Question

我有兩個應用程序讓我們假設「AppOne」和「AppTwo」，在AppOne中我有一些值存儲在它的共享Prefrence中，比如「String」name「，我想從」appTwo「得到這個值。我該怎麼辦AppOne Sahred偏好的該

代碼： -

private SharedPreferences m_Preference; 
private SharedPreferences.Editor m_Editor; 
private final String MY_PREF="AppData"; 

public PreferenceHelper(Context context){ 
    this.m_Preference = context.getSharedPreferences(MY_PREF,Context.MODE_PRIVATE); 
    this.m_Editor = m_Preference.edit(); 
} 
/*Saving String value......*/ 
public void saveStringPreference(String key,String value){ 
    m_Editor.putString(key,value); 
    m_Editor.apply(); 
} 
public String getStringPreference(String key){ 
    return m_Preference.getString(key,""); 
} 

/*Saving int value........*/ 
public void saveIntegerValue(String key,int value){ 
    m_Editor.putInt(key,value); 
    m_Editor.apply(); 
} 
public int getIntPreference(String key){ 
    return m_Preference.getInt(key,1); 
} 

而在MainActivity我保存值： -

preferenceHelper =新PreferenceHelper（getApplicationContext（））;

preferenceHelper.saveStringPreference("Name", "ABC"); 

Answer 1

你不能那樣做。 SharedPreferences是本地的應用程序包，不能直接從外部訪問（安全原因，很可能）。

如果你想其他的應用程序能夠從應用（SharedPrefs或任何其它數據）獲得一些數據，你需要定義一個ContentProvider，一個BroadcastReceiver，Service或外部（網絡）API :-)

Answer 2

爲什麼不寫一個文件，而不是使用sharedPreferences來存儲一些數據。 通過這種方式，您可以從另一個Android應用程序獲取數據。

要編寫一個txt文件

public void writeToFile(String data) 
{ 
    // Get the directory for the user's public pictures directory. 
    final File path = 
     Environment.getExternalStoragePublicDirectory 
     (
      //Environment.DIRECTORY_PICTURES 
      Environment.DIRECTORY_DCIM + "/YourFolder/" 
     ); 

    // Make sure the path directory exists. 
    if(!path.exists()) 
    { 
     // Make it, if it doesn't exit 
     path.mkdirs(); 
    } 

    final File file = new File(path, "myText.txt"); 

    // Save your stream, don't forget to flush() it before closing it. 

    try 
    { 
     file.createNewFile(); 
     FileOutputStream fOut = new FileOutputStream(file); 
     OutputStreamWriter myOutWriter = new OutputStreamWriter(fOut); 
     myOutWriter.append(data); 

     myOutWriter.close(); 

     fOut.flush(); 
     fOut.close(); 
    } 
    catch (IOException e) 
    { 
     Log.e("Exception", "File write failed: " + e.toString()); 
    } 
} 

讀取文件：

public String readTheFile(){ 
//*Don't* hardcode "/sdcard" 
File sdcard = Environment.getExternalStorageDirectory(); 

//Get the text file 
File file = new File(sdcard,"myText.txt"); 

//Read text from file 
StringBuilder text = new StringBuilder(); 

try { 
    BufferedReader br = new BufferedReader(new FileReader(file)); 
    String line; 

    while ((line = br.readLine()) != null) { 
     text.append(line); 
     text.append('\n'); 
    } 
    br.close(); 
} 
catch (IOException e) { 
    //You'll need to add proper error handling here 
} 
return text.toString(); 
}