ch.ethz.inf.vs.a1.fabischn.ble.MainActivity.java Source code

Java tutorial

Introduction

Here is the source code for ch.ethz.inf.vs.a1.fabischn.ble.MainActivity.java

Source

/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package ch.ethz.inf.vs.a1.fabischn.ble;

import android.app.Activity;
import android.app.ListActivity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothManager;
import android.bluetooth.le.BluetoothLeScanner;
import android.bluetooth.le.ScanCallback;
import android.bluetooth.le.ScanFilter;
import android.bluetooth.le.ScanResult;
import android.bluetooth.le.ScanSettings;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.os.Handler;
import android.support.v4.app.ActivityCompat;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends ListActivity {

    private BluetoothAdapter mBluetoothAdapter;
    private BluetoothLeScanner mBluetoothLeScanner;
    private ScanFilter mScanFilter;
    private ArrayList<ScanFilter> mScanFilters;
    private ScanSettings mScanSettings;
    private final static int REQUEST_ENABLE_BT = 1;
    private static final long SCAN_PERIOD = 10000;

    private LeDeviceListAdapter mLeDeviceListAdapter;
    private boolean mScanning;
    private Handler mHandler;

    // Stops scanning after 10 seconds.

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getActionBar().setTitle(R.string.title_devices);
        mHandler = new Handler();

        // TODO when bluetooth is off, concurrently the onCreate keeps running.
        if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
            Toast.makeText(this, R.string.ble_not_supported, Toast.LENGTH_LONG).show();
            finish();
            return;
        }

        final BluetoothManager bluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
        mBluetoothAdapter = bluetoothManager.getAdapter();

        // TODO onActivityResult, check if Cancelled or not, then continue or leave
        if (mBluetoothAdapter == null || !mBluetoothAdapter.isEnabled()) {
            Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
            // REQUEST_ENABLE_BT will be returned as requestCode from onActivityResult
            startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
        }

        // TODO change this if onActivity Result is used
        // Continues scanning if enabled, else toast and finish
        if (mBluetoothAdapter == null || !mBluetoothAdapter.isEnabled()) {
            Toast.makeText(this, R.string.ble_not_supported, Toast.LENGTH_LONG).show();
            finish();
            return;
        }

        // TODO lookup the correct idiom for this, look at onRequestPermissionsResult
        // We need this for Android 6.0+
        if (checkLocationPermission()) {

        } else {
            ActivityCompat.requestPermissions(this,
                    new String[] { android.Manifest.permission.ACCESS_FINE_LOCATION }, 1);
        }

        if (mBluetoothAdapter != null) {
            mBluetoothLeScanner = mBluetoothAdapter.getBluetoothLeScanner();
        }
        ScanFilter.Builder filterBuilder = new ScanFilter.Builder();
        mScanFilter = filterBuilder.setDeviceName("Smart Humigadget").build();
        ScanSettings.Builder settingsBuilder = new ScanSettings.Builder();
        mScanSettings = settingsBuilder.setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY)
                //                .setMatchMode(ScanSettings.CALLBACK_TYPE_ALL_MATCHES)
                //                .setCallbackType(ScanSettings.CALLBACK_TYPE_ALL_MATCHES)
                .build();
        mScanFilters = new ArrayList<ScanFilter>();
        mScanFilters.add(mScanFilter);

    }

    public boolean checkLocationPermission() {
        String permission = "android.permission.ACCESS_FINE_LOCATION";
        int res = this.checkCallingOrSelfPermission(permission);
        return (res == PackageManager.PERMISSION_GRANTED);
    }

    // TODO clean this up
    public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
        switch (requestCode) {
        case 1: {
            // If request is cancelled, the result arrays are empty.
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

            } else {
                // permission denied, boo! Disable the
                // functionality that depends on this permission.
            }
            return;
        }
        // other 'case' lines to check for other
        // permissions this app might request
        }
    }

    protected void onResume() {
        super.onResume();

        // Ensures Bluetooth is enabled on the device.  If Bluetooth is not currently enabled,
        // fire an intent to display a dialog asking the user to grant permission to enable it.
        if (!mBluetoothAdapter.isEnabled()) {
            if (!mBluetoothAdapter.isEnabled()) {
                Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
                startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
            }
        }
        // We need this for Android 6.0+
        if (checkLocationPermission()) {
            // TODO hooray
        } else {
            ActivityCompat.requestPermissions(this,
                    new String[] { android.Manifest.permission.ACCESS_FINE_LOCATION }, 1);
        }

        // Initializes list view adapter.
        mLeDeviceListAdapter = new LeDeviceListAdapter();
        setListAdapter(mLeDeviceListAdapter);
        scanLeDevice(true);
    }

    // TODO this is were we get from the Enable Permission Intent
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        // User chose not to enable Bluetooth.
        if (requestCode == REQUEST_ENABLE_BT && resultCode == Activity.RESULT_CANCELED) {
            finish();
            return;
        }
        super.onActivityResult(requestCode, resultCode, data);
    }

    @Override
    protected void onPause() {
        super.onPause();
        scanLeDevice(false);
        mLeDeviceListAdapter.clear();
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
    }

    @Override
    protected void onStop() {
        super.onStop();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        Log.v("Menu Created:", "onCreateOptionsMenu");
        getMenuInflater().inflate(R.menu.main, menu);
        if (!mScanning) {
            menu.findItem(R.id.menu_stop).setVisible(false);
            menu.findItem(R.id.menu_scan).setVisible(true);
            menu.findItem(R.id.menu_refresh).setActionView(null);
        } else {
            menu.findItem(R.id.menu_stop).setVisible(true);
            menu.findItem(R.id.menu_scan).setVisible(false);
            menu.findItem(R.id.menu_refresh).setActionView(R.layout.actionbar_indeterminate_progress);
        }
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
        case R.id.menu_scan:
            mLeDeviceListAdapter.clear();
            scanLeDevice(true);
            break;
        case R.id.menu_stop:
            scanLeDevice(false);
            break;
        }
        return true;
    }

    @Override
    protected void onListItemClick(ListView l, View v, int position, long id) {
        final BluetoothDevice device = mLeDeviceListAdapter.getDevice(position);
        if (device == null)
            return;
        final Intent intent = new Intent(this, DeviceControlActivity.class);
        intent.putExtra(DeviceControlActivity.EXTRAS_DEVICE_NAME, device.getName());
        intent.putExtra(DeviceControlActivity.EXTRAS_DEVICE_ADDRESS, device.getAddress());
        if (mScanning) {
            // mBluetoothAdapter.stopLeScan(mLeScanCallback);
            mBluetoothLeScanner.stopScan(mScanCallback);
            mScanning = false;
        }
        startActivity(intent);
    }

    private void scanLeDevice(final boolean enable) {
        if (enable) {
            // Stops scanning after a pre-defined scan period.
            mHandler.postDelayed(new Runnable() {
                @Override
                public void run() {
                    mScanning = false;
                    mBluetoothLeScanner.stopScan(mScanCallback);
                    invalidateOptionsMenu();
                }
            }, SCAN_PERIOD);

            mScanning = true;
            mBluetoothLeScanner.startScan(mScanFilters, mScanSettings, mScanCallback);
        } else {
            mScanning = false;
            mBluetoothLeScanner.stopScan(mScanCallback);
        }
        invalidateOptionsMenu();
    }

    private class LeDeviceListAdapter extends BaseAdapter {
        private ArrayList<BluetoothDevice> mLeDevices;
        private LayoutInflater mInflator;

        public LeDeviceListAdapter() {
            super();
            mLeDevices = new ArrayList<BluetoothDevice>();
            mInflator = MainActivity.this.getLayoutInflater();
        }

        public void addDevice(BluetoothDevice device) {
            if (!mLeDevices.contains(device)) {
                mLeDevices.add(device);
            }
        }

        public BluetoothDevice getDevice(int position) {
            return mLeDevices.get(position);
        }

        public void clear() {
            mLeDevices.clear();
        }

        @Override
        public int getCount() {
            return mLeDevices.size();
        }

        @Override
        public Object getItem(int i) {
            return mLeDevices.get(i);
        }

        @Override
        public long getItemId(int i) {
            return i;
        }

        @Override
        public View getView(int i, View view, ViewGroup viewGroup) {
            ViewHolder viewHolder;
            // General ListView optimization code.
            if (view == null) {
                view = mInflator.inflate(R.layout.listitem_device, null);
                viewHolder = new ViewHolder();
                viewHolder.deviceAddress = (TextView) view.findViewById(R.id.device_address);
                viewHolder.deviceName = (TextView) view.findViewById(R.id.device_name);
                view.setTag(viewHolder);
            } else {
                viewHolder = (ViewHolder) view.getTag();
            }

            BluetoothDevice device = mLeDevices.get(i);
            final String deviceName = device.getName();
            if (deviceName != null && deviceName.length() > 0)
                viewHolder.deviceName.setText(deviceName);
            else
                viewHolder.deviceName.setText(R.string.unknown_device);
            viewHolder.deviceAddress.setText(device.getAddress());

            return view;
        }
    }

    private ScanCallback mScanCallback = new ScanCallback() {
        @Override
        public void onScanResult(int callbackType, final ScanResult result) {
            super.onScanResult(callbackType, result);
            runOnUiThread(new Runnable() {
                @Override
                public void run() {
                    mLeDeviceListAdapter.addDevice(result.getDevice());
                    mLeDeviceListAdapter.notifyDataSetChanged();
                }
            });
        }

        @Override
        public void onBatchScanResults(List<ScanResult> results) {
            super.onBatchScanResults(results);
        }

        @Override
        public void onScanFailed(int errorCode) {
            super.onScanFailed(errorCode);
            Toast.makeText(getParent(), R.string.ble_not_supported, Toast.LENGTH_LONG).show();
        }
    };

    static class ViewHolder {
        TextView deviceName;
        TextView deviceAddress;
    }
}