SharedPreferences lesen

Question

Wie kann ich SharedPrefs lesen?

Mein SettingsActivity:

package com.deutz.obd2; 


import android.annotation.TargetApi; 
import android.content.Context; 
import android.content.Intent; 
import android.content.res.Configuration; 
import android.net.Uri; 
import android.os.Build; 
import android.os.Bundle; 
import android.preference.ListPreference; 
import android.preference.Preference; 
import android.preference.PreferenceActivity; 
import android.support.v7.app.ActionBar; 
import android.preference.PreferenceFragment; 
import android.preference.PreferenceManager; 
import android.preference.RingtonePreference; 
import android.text.TextUtils; 
import android.view.MenuItem; 

import java.util.List; 

/** 
* A {@link PreferenceActivity} that presents a set of application settings. On 
* handset devices, settings are presented as a single list. On tablets, 
* settings are split by category, with category headers shown to the left of 
* the list of settings. 
* <p> 
* See <a href="http://developer.android.com/design/patterns/settings.html"> 
* Android Design: Settings</a> for design guidelines and the <a 
* href="http://developer.android.com/guide/topics/ui/settings.html">Settings 
* API Guide</a> for more information on developing a Settings UI. 
*/ 
public class SettingsActivity extends AppCompatPreferenceActivity { 
    /** 
    * A preference value change listener that updates the preference's summary 
    * to reflect its new value. 
    */ 
    private static Preference.OnPreferenceChangeListener sBindPreferenceSummaryToValueListener = new Preference.OnPreferenceChangeListener() { 
     @Override 
     public boolean onPreferenceChange(Preference preference, Object value) { 
      String stringValue = value.toString(); 

      if (preference instanceof ListPreference) { 
       // For list preferences, look up the correct display value in 
       // the preference's 'entries' list. 
       ListPreference listPreference = (ListPreference) preference; 
       int index = listPreference.findIndexOfValue(stringValue); 

       // Set the summary to reflect the new value. 
       preference.setSummary(
         index >= 0 
           ? listPreference.getEntries()[index] 
           : null); 

      } else { 
       // For all other preferences, set the summary to the value's 
       // simple string representation. 
       preference.setSummary(stringValue); 
      } 
      return true; 
     } 
    }; 

    /** 
    * Helper method to determine if the device has an extra-large screen. For 
    * example, 10" tablets are extra-large. 
    */ 
    private static boolean isXLargeTablet(Context context) { 
     return (context.getResources().getConfiguration().screenLayout 
       & Configuration.SCREENLAYOUT_SIZE_MASK) >= Configuration.SCREENLAYOUT_SIZE_XLARGE; 
    } 

    /** 
    * Binds a preference's summary to its value. More specifically, when the 
    * preference's value is changed, its summary (line of text below the 
    * preference title) is updated to reflect the value. The summary is also 
    * immediately updated upon calling this method. The exact display format is 
    * dependent on the type of preference. 
    * 
    * @see #sBindPreferenceSummaryToValueListener 
    */ 
    private static void bindPreferenceSummaryToValue(Preference preference) { 
     // Set the listener to watch for value changes. 
     preference.setOnPreferenceChangeListener(sBindPreferenceSummaryToValueListener); 

     // Trigger the listener immediately with the preference's 
     // current value. 
     sBindPreferenceSummaryToValueListener.onPreferenceChange(preference, 
       PreferenceManager 
         .getDefaultSharedPreferences(preference.getContext()) 
         .getString(preference.getKey(), "")); 
    } 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setupActionBar(); 

     getFragmentManager().beginTransaction() 
       .replace(android.R.id.content, new SettingsPreferenceFragment()).commit(); 
    } 

    /** 
    * Set up the {@link android.app.ActionBar}, if the API is available. 
    */ 
    private void setupActionBar() { 
     ActionBar actionBar = getSupportActionBar(); 
     if (actionBar != null) { 
      // Show the Up button in the action bar. 
      actionBar.setDisplayHomeAsUpEnabled(true); 
     } 
    } 

    /** 
    * {@inheritDoc} 
    */ 
    @Override 
    public boolean onIsMultiPane() { 
     return isXLargeTablet(this); 
    } 

    /** 
    * {@inheritDoc} 
    */ 

    /** 
    * This method stops fragment injection in malicious applications. 
    * Make sure to deny any unknown fragments here. 
    */ 
    protected boolean isValidFragment(String fragmentName) { 
     return PreferenceFragment.class.getName().equals(fragmentName) 
       || SettingsPreferenceFragment.class.getName().equals(fragmentName); 
    } 

    /** 
    * This fragment shows general preferences only. It is used when the 
    * activity is showing a two-pane settings UI. 
    */ 
    @TargetApi(Build.VERSION_CODES.HONEYCOMB) 
    public static class SettingsPreferenceFragment extends PreferenceFragment { 
     @Override 
     public void onCreate(Bundle savedInstanceState) { 
      super.onCreate(savedInstanceState); 
      addPreferencesFromResource(R.xml.pref_settings); 
      setHasOptionsMenu(true); 

      // Bind the summaries of EditText/List/Dialog/Ringtone preferences 
      // to their values. When their values change, their summaries are 
      // updated to reflect the new value, per the Android Design 
      // guidelines. 
      bindPreferenceSummaryToValue(findPreference("key_connection_type")); 
      bindPreferenceSummaryToValue(findPreference("key_server_ip")); 
      bindPreferenceSummaryToValue(findPreference("key_server_port")); 
     } 

     @Override 
     public boolean onOptionsItemSelected(MenuItem item) { 
      int id = item.getItemId(); 
      if (id == android.R.id.home) { 
       startActivity(new Intent(getActivity(), MainActivity.class)); 
       return true; 
      } 
      return super.onOptionsItemSelected(item); 
     } 
    } 

} 

Meine pref XML:

<?xml version="1.0" encoding="utf-8"?> 
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"> 

    <ListPreference 
     android:defaultValue="1" 
     android:title="@string/pref_title_connection_type" 
     android:entries="@array/pref_sync_connection_type_titles" 
     android:entryValues="@array/pref_sync_connection_type_values" 
     android:key="key_connection_type" 
     android:negativeButtonText="@null" 
     android:positiveButtonText="@null" 
     android:summary="@string/pref_summary_connection_type" /> 
    <EditTextPreference 
     android:defaultValue="@string/pref_default_server_ip" 
     android:selectAllOnFocus="true" 
     android:singleLine="true" 
     android:title="@string/pref_title_server_ip" 
     android:key="key_server_ip" /> 
    <EditTextPreference 
     android:defaultValue="@string/pref_default_server_port" 
     android:selectAllOnFocus="true" 
     android:singleLine="true" 
     android:title="@string/pref_title_server_port" 
     android:key="key_server_port" /> 
</PreferenceScreen> 

Ich mag würde die beide EditTextPrefs und die ListPref in anderen Klassen lesen. Die Liste sollte definieren, wie eine Verbindung hergestellt werden soll und der EditText gibt die IP und den Port für Wifi an. Ich habe also zwei Klassen für TCP und Bluetooth und möchte die IP und den Port in der TCP-Klasse verwenden.

Wie kann ich die gespeicherten Einstellungen lesen? Pls help

Answer 1

verwenden

SharedPreference sharedPreference = PreferenceManager.getDefaultSharedPreferences(context); 
sharedPreference.getString("KEY_OF_WHAT_YOU_WANT","DEFAULT_VALUE");