Bluetooth_4.3 BLE蓝牙通信

【实例截图】

用处不大

/*
 * 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 com.example.bluetooth.le;

import android.annotation.SuppressLint;
import android.app.ActionBar;
import android.app.Activity;
import android.app.ListActivity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothManager;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.os.Handler;
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.UUID;

/**
 * Activity for scanning and displaying available Bluetooth LE devices.
 */
@SuppressLint("NewApi")
public class DeviceScanActivity extends ListActivity {
	
    private LeDeviceListAdapter mLeDeviceListAdapter;
    private BluetoothAdapter mBluetoothAdapter;
    private boolean mScanning;
    private Handler mHandler;
    private ActionBar mActionBar = null;

    private static final int REQUEST_ENABLE_BT = 1;
    // 10秒后停止查找搜索.
    private static final long SCAN_PERIOD = 10000;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        
        mActionBar = getActionBar();
        mActionBar.setTitle("Ken Ble Scan");
        //mActionBar.setTitle(R.string.title_devices);
        mHandler = new Handler();

        // 检查当前手机是否支持ble 蓝牙,如果不支持退出程序
        if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
            Toast.makeText(this, R.string.ble_not_supported, Toast.LENGTH_SHORT).show();
            finish();
        }

        // 初始化 Bluetooth adapter, 通过蓝牙管理器得到一个参考蓝牙适配器(API必须在以上android4.3或以上和版本)
        final BluetoothManager bluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
        mBluetoothAdapter = bluetoothManager.getAdapter();

        // 检查设备上是否支持蓝牙
        if (mBluetoothAdapter == null) {
            Toast.makeText(this, R.string.error_bluetooth_not_supported, Toast.LENGTH_SHORT).show();
            finish();
            return;
        }
    }
    //======================end of oncreate 
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);
        if (!mScanning) {
        	System.out.println(" Didnot Scan ===");
            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 {
        	System.out.println(" Scaning ==== ");
            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 onResume() {
        super.onResume();
        //其实这个是 每次回到这个界面 或刚启动的时候都会执行到的一句话
        System.out.println("ON Resume ");
        
        // 为了确保设备上蓝牙能使用, 如果当前蓝牙设备没启用,弹出对话框向用户要求授予权限来启用
        if (!mBluetoothAdapter.isEnabled()) {
            if (!mBluetoothAdapter.isEnabled()) {
                Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
                startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
            }
        }

        // Initializes list view adapter. 蓝牙列表适配器  很专业的样子 继承的是 listactivity 所以可以直接设置 适配器 之后开启蓝牙搜索
        mLeDeviceListAdapter = new LeDeviceListAdapter();
        setListAdapter(mLeDeviceListAdapter);
        scanLeDevice(true);
    }//end of onresume

    @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);
    }//end of onactivityresult 
 
    @Override
    protected void onPause() {
        super.onPause();
        scanLeDevice(false);
        mLeDeviceListAdapter.clear();
    }
    //到这里 还没有连接设备 只是 开启了另一个activity 并将地址还有设备名传过去了。
    @Override
    protected void onListItemClick(ListView l, View v, int position, long id) {
    	//扫描到的是一个蓝牙列表 通过位置得到 要连接的是哪一个。
        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);
            mScanning = false;
        }
        startActivity(intent);
    }
    //这个函数可以启动 蓝牙搜索 十秒之后结束
    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;
                    mBluetoothAdapter.stopLeScan(mLeScanCallback);
                    invalidateOptionsMenu();
                }
            }, SCAN_PERIOD);

            mScanning = true;
            mBluetoothAdapter.startLeScan(mLeScanCallback);
        } else {
            mScanning = false;
            mBluetoothAdapter.stopLeScan(mLeScanCallback);
        }
        invalidateOptionsMenu();
    }

    // Adapter for holding devices found through scanning.
    //蓝牙列表  这个列表是从baseadapter继承来的，继承这个类需要实现4个 方法，
    private class LeDeviceListAdapter extends BaseAdapter {
        private ArrayList<BluetoothDevice> mLeDevices;
        private LayoutInflater mInflator;

        //构造方法  创建这个类的时候就 创建一个蓝牙列表  还有创建  一个XML====================== 
        public LeDeviceListAdapter() {
            super();
            mLeDevices = new ArrayList<BluetoothDevice>();
            mInflator = DeviceScanActivity.this.getLayoutInflater();
        }

        //================蓝牙设备列表 添加 蓝牙  这个方法被scancallback调用 添加设备
        public void addDevice(BluetoothDevice device) {
            if(!mLeDevices.contains(device)) {
                mLeDevices.add(device);
            }
        }
        //得到蓝牙设备 传入的是listadepter的position 返回的是设备列表中的第 position个设备
        public BluetoothDevice getDevice(int position) {
            return mLeDevices.get(position);
        }
        //clear 蓝牙列表===================
        public void clear() {
            mLeDevices.clear();
        }
        //得到蓝牙列表的数量
        @Override
        public int getCount() {
            return mLeDevices.size();
        }
        //返回第I个device
        @Override
        public Object getItem(int i) {
            return mLeDevices.get(i);
        }
        //这个函数是得到点击的 是第几个item
        @Override
        public long getItemId(int i) {
            return i;
        }
        //这个getview 里面的内容就是将设备的名字以及地址写入了text中
        @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();
         
            }
            //这里就是关键的地方了，可以得到蓝牙list中的某个设备  
            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;
        }
    }//end of ledevicelistadapter

    // Device scan callback.
    private BluetoothAdapter.LeScanCallback mLeScanCallback = new BluetoothAdapter.LeScanCallback() {

        @Override
        public void onLeScan(final BluetoothDevice device, int rssi, byte[] scanRecord) {
            runOnUiThread(new Runnable() {
                @Override
                public void run() {                	
                    mLeDeviceListAdapter.addDevice(device);
                    mLeDeviceListAdapter.notifyDataSetChanged();
                }
            });
        }
    };//===============end of lescancallback 这个callback 函数 会将device 传过来 这里可以添加设备  

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