安卓获取设备蓝牙连接状态

获取已绑定设备的蓝牙信息与连接状态（注：获取连接状态方法被隐藏，必须通过反射调用），以下为示例代码：

package com.example.bluetoothtest;

import androidx.appcompat.app.AppCompatActivity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.os.Bundle;
import android.util.Log;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Set;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

		//获取BluetoothAdapter
        BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        showBondedDevice(bluetoothAdapter);
    }

    //获取已绑定设备信息和连接状态
    private void showBondedDevice(BluetoothAdapter bluetoothAdapter) {
        Set<BluetoothDevice> deviceList = bluetoothAdapter.getBondedDevices();
        for (BluetoothDevice device : deviceList) {
            Log.d("Jason", "Name:" + device.getName() + "   Mac:" + device.getAddress());

            try {
                //使用反射调用获取设备连接状态方法
                Method isConnectedMethod = BluetoothDevice.class.getDeclaredMethod("isConnected", (Class[]) null);
                isConnectedMethod.setAccessible(true);
                boolean isConnected = (boolean) isConnectedMethod.invoke(device, (Object[]) null);
                Log.d("Jason", "isConnected：" + isConnected);
            } catch (NoSuchMethodException e) {
                e.printStackTrace();
            } catch (IllegalAccessException e) {
                e.printStackTrace();
            } catch (InvocationTargetException e) {
                e.printStackTrace();
            }
        }
    }
}