Android ble简单使用（初始化）

网上已经有很多优秀的开源框架了，为了熟悉ble的整个流程还是要自己写一下的。

蓝牙权限

动态申请权限

因为这里只有一个权限需要动态申请，所以用下面的代码

//检查权限是否打开
private void checkPermission() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (ContextCompat.checkSelfPermission(activity,
                    Manifest.permission.ACCESS_COARSE_LOCATION) !=
                    PackageManager.PERMISSION_GRANTED) {
                if (ActivityCompat.shouldShowRequestPermissionRationale(activity,
                        Manifest.permission.ACCESS_COARSE_LOCATION)) {
                    //彻底拒绝
                    toSelfSetting(activity);
                } else {
                    //未彻底拒绝
                    ActivityCompat.requestPermissions(activity,
                            new String[]{Manifest.permission.ACCESS_COARSE_LOCATION},
                            1);
                }
            }
        }
    }
//用户操作回调
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (requestCode == 1) {
            for (int i = 0; i < permissions.length; i++) {
                if (grantResults[i] == PackageManager.PERMISSION_GRANTED){
                    //申请成功
                }else {
                    toSelfSetting(activity);
                }
            }
        }
    }
//跳转到应用设置页面
private void toSelfSetting(Context context) {
        Intent mIntent = new Intent();
        mIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        mIntent.setAction("android.settings.APPLICATION_DETAILS_SETTINGS");
        mIntent.setData(Uri.fromParts("package", context.getPackageName(), null));
        context.startActivity(mIntent);
    }

获取蓝牙适配器

bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

判断设备是否支持蓝牙

if (bluetoothAdapter == null) {//为空不支持
return;
}

注册蓝牙广播监听蓝牙状态

private void register() {
        if (receiver == null) {
            receiver = new BTStateReceiver();
        }
        receiver.setCallback(this);
        IntentFilter intentFilter = new IntentFilter();
        intentFilter.addAction(BluetoothAdapter.ACTION_STATE_CHANGED);
        intentFilter.addAction(BluetoothDevice.ACTION_ACL_CONNECTED);
        intentFilter.addAction(BluetoothDevice.ACTION_ACL_DISCONNECTED);
        intentFilter.addAction("android.bluetooth.BluetoothAdapter.STATE_OFF");
        intentFilter.addAction("android.bluetooth.BluetoothAdapter.STATE_ON");
        activity.registerReceiver(receiver, intentFilter);
    }
    private void unregister() {
        if (receiver != null) {
            activity.unregisterReceiver(receiver);
            receiver = null;
        }
    }

BTStateReceiver 的代码

public class BTStateReceiver extends BroadcastReceiver {
    private BTStateCallback callback;
    @Override
    public void onReceive(Context context, Intent intent) {
        String action = intent.getAction();
        BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
        if (action == null) {
            return;
        }
        switch (action) {
            case BluetoothDevice.ACTION_ACL_CONNECTED:
                break;
            case BluetoothDevice.ACTION_ACL_DISCONNECTED:
                break;
            case BluetoothAdapter.ACTION_STATE_CHANGED:
                int blueState = intent.getIntExtra(BluetoothAdapter.EXTRA_STATE, 0);
                switch (blueState) {
                    case BluetoothAdapter.STATE_OFF:
                        callback.onBTOff();
                        break;
                    case BluetoothAdapter.STATE_ON:
                        Toast.makeText(context, "蓝牙已开启", Toast.LENGTH_SHORT).show();
                        break;
                }
                break;
        }
    }
    public void setCallback(BTStateCallback callback) {
        this.callback = callback;
    }
    public interface BTStateCallback {
        void onBTOff();
    }
}

当前只实现蓝牙被关闭时候的操作

实现回调

前面注册广播的时候调用了setCallback的方法，所以当前类需要 implements BTStateCallback 实现这个里面的接口

@Override
    public void onBTOff() {
        openBT();
    }
    private void openBT() {
        Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
        startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
    }

注册完广播之后 判断是否打开蓝牙

if (!bluetoothAdapter.isEnabled()) {
openBT();
}

当前初始化已经完成

下一篇说一下扫描吧，堆在一起很乱！链接

作者：qq313629058