1 /*
2  * Copyright (C) 2015 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 
17 package com.example.android.bluetoothadvertisements;
18 
19 import android.bluetooth.le.ScanResult;
20 import android.content.Context;
21 import android.os.SystemClock;
22 import android.view.LayoutInflater;
23 import android.view.View;
24 import android.view.ViewGroup;
25 import android.widget.BaseAdapter;
26 import android.widget.TextView;
27 
28 import java.util.ArrayList;
29 import java.util.concurrent.TimeUnit;
30 
31 /**
32  * Holds and displays {@link ScanResult}s, used by {@link ScannerFragment}.
33  */
34 public class ScanResultAdapter extends BaseAdapter {
35 
36     private ArrayList<ScanResult> mArrayList;
37 
38     private Context mContext;
39 
40     private LayoutInflater mInflater;
41 
ScanResultAdapter(Context context, LayoutInflater inflater)42     ScanResultAdapter(Context context, LayoutInflater inflater) {
43         super();
44         mContext = context;
45         mInflater = inflater;
46         mArrayList = new ArrayList<>();
47     }
48 
49     @Override
getCount()50     public int getCount() {
51         return mArrayList.size();
52     }
53 
54     @Override
getItem(int position)55     public Object getItem(int position) {
56         return mArrayList.get(position);
57     }
58 
59     @Override
getItemId(int position)60     public long getItemId(int position) {
61         return mArrayList.get(position).getDevice().getAddress().hashCode();
62     }
63 
64     @Override
getView(int position, View view, ViewGroup parent)65     public View getView(int position, View view, ViewGroup parent) {
66 
67         // Reuse an old view if we can, otherwise create a new one.
68         if (view == null) {
69             view = mInflater.inflate(R.layout.listitem_scanresult, null);
70         }
71 
72         TextView deviceNameView = (TextView) view.findViewById(R.id.device_name);
73         TextView deviceAddressView = (TextView) view.findViewById(R.id.device_address);
74         TextView lastSeenView = (TextView) view.findViewById(R.id.last_seen);
75 
76         ScanResult scanResult = mArrayList.get(position);
77 
78         String name = scanResult.getDevice().getName();
79         if (name == null) {
80             name = mContext.getResources().getString(R.string.no_name);
81         }
82         deviceNameView.setText(name);
83         deviceAddressView.setText(scanResult.getDevice().getAddress());
84         lastSeenView.setText(getTimeSinceString(mContext, scanResult.getTimestampNanos()));
85 
86         return view;
87     }
88 
89     /**
90      * Search the adapter for an existing device address and return it, otherwise return -1.
91      */
getPosition(String address)92     private int getPosition(String address) {
93         int position = -1;
94         for (int i = 0; i < mArrayList.size(); i++) {
95             if (mArrayList.get(i).getDevice().getAddress().equals(address)) {
96                 position = i;
97                 break;
98             }
99         }
100         return position;
101     }
102 
103 
104     /**
105      * Add a ScanResult item to the adapter if a result from that device isn't already present.
106      * Otherwise updates the existing position with the new ScanResult.
107      */
add(ScanResult scanResult)108     public void add(ScanResult scanResult) {
109 
110         int existingPosition = getPosition(scanResult.getDevice().getAddress());
111 
112         if (existingPosition >= 0) {
113             // Device is already in list, update its record.
114             mArrayList.set(existingPosition, scanResult);
115         } else {
116             // Add new Device's ScanResult to list.
117             mArrayList.add(scanResult);
118         }
119     }
120 
121     /**
122      * Clear out the adapter.
123      */
clear()124     public void clear() {
125         mArrayList.clear();
126     }
127 
128     /**
129      * Takes in a number of nanoseconds and returns a human-readable string giving a vague
130      * description of how long ago that was.
131      */
getTimeSinceString(Context context, long timeNanoseconds)132     public static String getTimeSinceString(Context context, long timeNanoseconds) {
133         String lastSeenText = context.getResources().getString(R.string.last_seen) + " ";
134 
135         long timeSince = SystemClock.elapsedRealtimeNanos() - timeNanoseconds;
136         long secondsSince = TimeUnit.SECONDS.convert(timeSince, TimeUnit.NANOSECONDS);
137 
138         if (secondsSince < 5) {
139             lastSeenText += context.getResources().getString(R.string.just_now);
140         } else if (secondsSince < 60) {
141             lastSeenText += secondsSince + " " + context.getResources()
142                     .getString(R.string.seconds_ago);
143         } else {
144             long minutesSince = TimeUnit.MINUTES.convert(secondsSince, TimeUnit.SECONDS);
145             if (minutesSince < 60) {
146                 if (minutesSince == 1) {
147                     lastSeenText += minutesSince + " " + context.getResources()
148                             .getString(R.string.minute_ago);
149                 } else {
150                     lastSeenText += minutesSince + " " + context.getResources()
151                             .getString(R.string.minutes_ago);
152                 }
153             } else {
154                 long hoursSince = TimeUnit.HOURS.convert(minutesSince, TimeUnit.MINUTES);
155                 if (hoursSince == 1) {
156                     lastSeenText += hoursSince + " " + context.getResources()
157                             .getString(R.string.hour_ago);
158                 } else {
159                     lastSeenText += hoursSince + " " + context.getResources()
160                             .getString(R.string.hours_ago);
161                 }
162             }
163         }
164 
165         return lastSeenText;
166     }
167 }
168