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Question

我有两个问题。我想连接我的服务。我可以连接，但我不能断开服务时{i}我的应用程序将崩溃。其他问题是我不能发送值到RXchar .... .. 所有问题都是显而易见的mService.disconnect(); 这是断开连接错误

RxChar错误

我的代码_ble_fragment

on a null object reference

DeviceList＆amp; UartService代码：

 switch1.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
            try {
                //send data to service
                if (isChecked) {
                    message = "1";
                } else {
                    message = "0";
                }
                value = message.getBytes("UTF-8");
                sendText.setText(message);
                mService.writeRXCharacteristic(value);
            } catch (UnsupportedEncodingException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    });
 scanButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Log.i("click", "按下去了");
            if (!mBtAdapter.isEnabled()) {
                Log.i(TAG, "onClick - BT not enabled yet");
                Intent enableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
                startActivityForResult(enableIntent, REQUEST_ENABLE_BT);
            } else {
                if (scanButton.getText().equals("Connect")) {
                    Log.i("scan", "open device");
                    switch1.setEnabled(true);
                    //Connect button pressed, open DeviceListActivity class, with popup windows that scan for devices
                    Intent newIntent = new Intent(getActivity(), DeviceListActivity.class);
                    startActivity(newIntent);
                } else {
                    //Disconnect button pressed

                       mService.disconnect();
                        Log.i("Diconnect", "Disconnect Ble");
                        // mHandler.removeCallbacks(runnable);

                }
            }
        }
    });

我能做什么？

Answer 1

你可以试试这个：

BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if(bluetoothAdapter.isEnabled()){
     bluetoothAdapter.disable();
}

你需要在下面添加两个权限：

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