1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.settings.nfc;
18
19import android.content.BroadcastReceiver;
20import android.content.Context;
21import android.content.Intent;
22import android.content.IntentFilter;
23import android.nfc.NfcAdapter;
24import android.os.UserManager;
25import android.preference.Preference;
26import android.preference.PreferenceScreen;
27import android.preference.SwitchPreference;
28
29import com.android.settings.R;
30
31/**
32 * NfcEnabler is a helper to manage the Nfc on/off checkbox preference. It is
33 * turns on/off Nfc and ensures the summary of the preference reflects the
34 * current state.
35 */
36public class NfcEnabler implements Preference.OnPreferenceChangeListener {
37    private final Context mContext;
38    private final SwitchPreference mSwitch;
39    private final PreferenceScreen mAndroidBeam;
40    private final NfcAdapter mNfcAdapter;
41    private final IntentFilter mIntentFilter;
42    private boolean mBeamDisallowed;
43
44    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
45        @Override
46        public void onReceive(Context context, Intent intent) {
47            String action = intent.getAction();
48            if (NfcAdapter.ACTION_ADAPTER_STATE_CHANGED.equals(action)) {
49                handleNfcStateChanged(intent.getIntExtra(NfcAdapter.EXTRA_ADAPTER_STATE,
50                        NfcAdapter.STATE_OFF));
51            }
52        }
53    };
54
55    public NfcEnabler(Context context, SwitchPreference switchPreference,
56            PreferenceScreen androidBeam) {
57        mContext = context;
58        mSwitch = switchPreference;
59        mAndroidBeam = androidBeam;
60        mNfcAdapter = NfcAdapter.getDefaultAdapter(context);
61        mBeamDisallowed = ((UserManager) mContext.getSystemService(Context.USER_SERVICE))
62                .hasUserRestriction(UserManager.DISALLOW_OUTGOING_BEAM);
63
64        if (mNfcAdapter == null) {
65            // NFC is not supported
66            mSwitch.setEnabled(false);
67            mAndroidBeam.setEnabled(false);
68            mIntentFilter = null;
69            return;
70        }
71        if (mBeamDisallowed) {
72            mAndroidBeam.setEnabled(false);
73        }
74        mIntentFilter = new IntentFilter(NfcAdapter.ACTION_ADAPTER_STATE_CHANGED);
75    }
76
77    public void resume() {
78        if (mNfcAdapter == null) {
79            return;
80        }
81        handleNfcStateChanged(mNfcAdapter.getAdapterState());
82        mContext.registerReceiver(mReceiver, mIntentFilter);
83        mSwitch.setOnPreferenceChangeListener(this);
84    }
85
86    public void pause() {
87        if (mNfcAdapter == null) {
88            return;
89        }
90        mContext.unregisterReceiver(mReceiver);
91        mSwitch.setOnPreferenceChangeListener(null);
92    }
93
94    public boolean onPreferenceChange(Preference preference, Object value) {
95        // Turn NFC on/off
96
97        final boolean desiredState = (Boolean) value;
98        mSwitch.setEnabled(false);
99
100        if (desiredState) {
101            mNfcAdapter.enable();
102        } else {
103            mNfcAdapter.disable();
104        }
105
106        return false;
107    }
108
109    private void handleNfcStateChanged(int newState) {
110        switch (newState) {
111        case NfcAdapter.STATE_OFF:
112            mSwitch.setChecked(false);
113            mSwitch.setEnabled(true);
114            mAndroidBeam.setEnabled(false);
115            mAndroidBeam.setSummary(R.string.android_beam_disabled_summary);
116            break;
117        case NfcAdapter.STATE_ON:
118            mSwitch.setChecked(true);
119            mSwitch.setEnabled(true);
120            mAndroidBeam.setEnabled(!mBeamDisallowed);
121            if (mNfcAdapter.isNdefPushEnabled() && !mBeamDisallowed) {
122                mAndroidBeam.setSummary(R.string.android_beam_on_summary);
123            } else {
124                mAndroidBeam.setSummary(R.string.android_beam_off_summary);
125            }
126            break;
127        case NfcAdapter.STATE_TURNING_ON:
128            mSwitch.setChecked(true);
129            mSwitch.setEnabled(false);
130            mAndroidBeam.setEnabled(false);
131            break;
132        case NfcAdapter.STATE_TURNING_OFF:
133            mSwitch.setChecked(false);
134            mSwitch.setEnabled(false);
135            mAndroidBeam.setEnabled(false);
136            break;
137        }
138    }
139}
140