在android中处理设备启动时的连接状态

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

private BroadcastReceiver mNetworkReceiver = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {
        // 网络连接状态变化的处理逻辑
        ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
        if (networkInfo != null && networkInfo.isConnected()) {
            // 网络已连接
        } else {
            // 网络未连接
        }
    }
};

@Override
protected void onResume() {
    super.onResume();
    IntentFilter filter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
    registerReceiver(mNetworkReceiver, filter);
}

@Override
protected void onPause() {
    super.onPause();
    unregisterReceiver(mNetworkReceiver);
}

<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.INTERNET"/>

private BroadcastReceiver mUsbReceiver = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {
        String action = intent.getAction();
        if (UsbManager.ACTION_USB_DEVICE_ATTACHED.equals(action)) {
            // USB设备已连接
            UsbDevice device = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
            // 处理USB设备连接逻辑
        } else if (UsbManager.ACTION_USB_DEVICE_DETACHED.equals(action)) {
            // USB设备已断开连接
            UsbDevice device = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
            // 处理USB设备断开连接逻辑
        }
    }
};

@Override
protected void onResume() {
    super.onResume();
    IntentFilter filter = new IntentFilter();
    filter.addAction(UsbManager.ACTION_USB_DEVICE_ATTACHED);
    filter.addAction(UsbManager.ACTION_USB_DEVICE_DETACHED);
    registerReceiver(mUsbReceiver, filter);
}

@Override
protected void onPause() {
    super.onPause();
    unregisterReceiver(mUsbReceiver);
}

private BroadcastReceiver mBluetoothReceiver = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {
        String action = intent.getAction();
        if (BluetoothAdapter.ACTION_STATE_CHANGED.equals(action)) {
            // 蓝牙设备状态发生变化
            int state = intent.getIntExtra(BluetoothAdapter.EXTRA_STATE, BluetoothAdapter.ERROR);
            if (state == BluetoothAdapter.STATE_ON) {
                // 蓝牙已打开
            } else if (state == BluetoothAdapter.STATE_OFF) {
                // 蓝牙已关闭
            }
        } else if (BluetoothDevice.ACTION_ACL_CONNECTED.equals(action)) {
            // 蓝牙设备已连接
            BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
            // 处理蓝牙设备连接逻辑
        } else if (BluetoothDevice.ACTION_ACL_DISCONNECTED.equals(action)) {
            // 蓝牙设备已断开连接
            BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
            // 处理蓝牙设备断开连接逻辑
        }
    }
};

@Override
protected void onResume() {
    super.onResume();
    IntentFilter filter = new IntentFilter();
    filter.addAction(BluetoothAdapter.ACTION_STATE_CHANGED);
    filter.addAction(BluetoothDevice.ACTION_ACL_CONNECTED);
    filter.addAction(BluetoothDevice.ACTION_ACL_DISCONNECTED);
    registerReceiver(mBluetoothReceiver, filter);
}

@Override
protected void onPause() {
    super.onPause();
    unregisterReceiver(mBluetoothReceiver);
}