다음 에러에 대한 질문입니다. [closed]

Question

다음 에러에 대한 질문입니다.

java.lang.RuntimeException: Unable to start activity ComponentInfo{com.tzutalin.dlibtest/com.tzutalin.dlibtest.Activity_Bluetooth}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2957)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3032)
        at android.app.ActivityThread.-wrap11(Unknown Source:0)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1696)
        at android.os.Handler.dispatchMessage(Handler.java:105)
        at android.os.Looper.loop(Looper.java:164)
        at android.app.ActivityThread.main(ActivityThread.java:6944)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)
     Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
        at com.tzutalin.dlibtest.Activity_Bluetooth.setUIControl(Activity_Bluetooth.java:85)
        at com.tzutalin.dlibtest.Activity_Bluetooth.onCreate(Activity_Bluetooth.java:47)
        at android.app.Activity.performCreate(Activity.java:7183)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1220)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2910)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3032) 
        at android.app.ActivityThread.-wrap11(Unknown Source:0) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1696) 
        at android.os.Handler.dispatchMessage(Handler.java:105) 
        at android.os.Looper.loop(Looper.java:164) 
        at android.app.ActivityThread.main(ActivityThread.java:6944) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374) 

 

문제는 java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference 

이거 같은데 구글링을 해도 답이 안보여서 이렇게 질문드립니다.

붉은색으로 표시된데가 java:85, java:47입니다

 

setUIControl();


    // Ask for location permission if not already allowed
    if(ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED)
        ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_COARSE_LOCATION}, 1);


    if (mBTArrayAdapter == null) {
        // Device does not support Bluetooth
        mBluetoothStatus.setText("Status: Bluetooth not found");
        Toast.makeText(getApplicationContext(),"Bluetooth device not found!", Toast.LENGTH_SHORT).show();
    }
    else {

        mListPairedDevicesBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v){
                listPairedDevices(v);
            }
        });
    }
}


/**
 * UI 생성 및 세팅
 */
private void setUIControl(){

    mBluetoothStatus = (TextView)findViewById(R.id.bluetoothStatus);
    mReadBuffer = (TextView) findViewById(R.id.readBuffer);
    mListPairedDevicesBtn = (Button)findViewById(R.id.PairedBtn);

    mBTArrayAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1);
    mBTAdapter = BluetoothAdapter.getDefaultAdapter(); // get a handle on the bluetooth radio

    mDevicesListView = (ListView)findViewById(R.id.devicesListView);
    mDevicesListView.setAdapter(mBTArrayAdapter);// assign model to view
    mDevicesListView.setOnItemClickListener(mDeviceClickListener);
}