Java tutorial
// Copyright 2015 The Vanadium Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. package io.v.android.debug; import android.content.SharedPreferences; import android.os.Bundle; import android.preference.Preference; import android.preference.PreferenceFragment; import android.preference.PreferenceManager; import android.support.v4.content.ContextCompat; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import io.v.android.VAndroidContext; import io.v.android.VOptionPreferenceUtils; import io.v.v23.OptionDefs; import io.v.v23.android.R; /** * A {@link PreferenceFragment} surfacing logging options. * <ul> * <li>VLEVEL - verbosity for vlog</li> * <li>VMODULE - per-module log verbosities</li> * </ul> */ public class DebugLogPreferenceFragment extends PreferenceFragment implements SharedPreferences.OnSharedPreferenceChangeListener { @Override public void onCreate(final Bundle savedInstanceState) { super.onCreate(savedInstanceState); final PreferenceManager pm = getPreferenceManager(); pm.setSharedPreferencesName(VAndroidContext.VANADIUM_OPTIONS_SHARED_PREFS); pm.getSharedPreferences().registerOnSharedPreferenceChangeListener(this); createPreferences(); } private void createPreferences() { addPreferencesFromResource(R.xml.pref_logging); final SharedPreferences sharedPreferences = getPreferenceManager().getSharedPreferences(); updateVLevelSummary(sharedPreferences, findPreference(OptionDefs.LOG_VLEVEL)); updateVModuleSummary(sharedPreferences, findPreference(OptionDefs.LOG_VMODULE)); } @Override public View onCreateView(final LayoutInflater inflater, final ViewGroup container, final Bundle savedInstanceState) { final View view = super.onCreateView(inflater, container, savedInstanceState); view.setBackgroundColor(ContextCompat.getColor(getActivity(), android.R.color.background_light)); return view; } private static void updateVLevelSummary(final SharedPreferences sharedPreferences, final Preference pref) { pref.setSummary(VOptionPreferenceUtils.readVLevel(sharedPreferences).map(Object::toString).orElse(null)); } private static void updateVModuleSummary(final SharedPreferences sharedPreferences, final Preference pref) { pref.setSummary(VOptionPreferenceUtils.readVModule(sharedPreferences).orElse(null)); } @Override public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) { final Preference pref = findPreference(key); if (pref == null) { return; } if (OptionDefs.LOG_VLEVEL.equals(key)) { updateVLevelSummary(sharedPreferences, pref); } else if (OptionDefs.LOG_VMODULE.equals(key)) { updateVModuleSummary(sharedPreferences, pref); } } public void reset() { getPreferenceManager().getSharedPreferences().edit().clear().commit(); // The easiest way to resync the preferences seems to be: getPreferenceScreen().removeAll(); createPreferences(); } }