Home | History | Annotate | Download | only in com.example.android.bluetoothadvertisements 
      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 
     42     ScanResultAdapter(Context context, LayoutInflater inflater) {
     43         super();
     44         mContext = context;
     45         mInflater = inflater;
     46         mArrayList = new ArrayList<>();
     47     }
     48 
     49     @Override
     50     public int getCount() {
     51         return mArrayList.size();
     52     }
     53 
     54     @Override
     55     public Object getItem(int position) {
     56         return mArrayList.get(position);
     57     }
     58 
     59     @Override
     60     public long getItemId(int position) {
     61         return mArrayList.get(position).getDevice().getAddress().hashCode();
     62     }
     63 
     64     @Override
     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      */
     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      */
    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      */
    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      */
    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