안녕하세요 webview의 goback사용시 페이지 로드가 안돼서 질문 드립니다.

Question

cose_webview = (WebView) findViewById(R.id.cosewebview);
        cose_webview.getSettings().setJavaScriptEnabled(true);
        cose_webview.setWebViewClient(new WebViewClient());
        cose_webview.setWebChromeClient(new WebChromeClient(){});
        final Intent intent = getIntent();
        Bundle push_url = intent.getExtras();
        if( push_url != null){
            if(push_url.getString("url") != null && !push_url.getString("url").equalsIgnoreCase("")) {
                uri = push_url.getString("url");
            }
        }
        try{
            String accountINFO = "user_PN="+ URLEncoder.encode(PHONENUM,"UTF-8")+"&user_SN="+URLEncoder.encode(sn,"UTF-8")
                    +"&user_imei="+URLEncoder.encode(imei,"UTF-8")+"&user_token="+URLEncoder.encode(user_Token,"UTF-8")+"&user_push="+URLEncoder.encode(user_push,"UTF-8")
                    +"&user_sdk="+URLEncoder.encode(SDK, "UTF-8");
            cose_webview.postUrl(uri, accountINFO.getBytes());
        }catch (Exception e) {
        }

이게 웹뷰쪽 코드구요

@Override
    public boolean onKeyDown(int keyCode, KeyEvent event){
        if((keyCode == KeyEvent.KEYCODE_BACK) && cose_webview.canGoBack() ){
            cose_webview.goBack();
            return true;
        }
        if ((keyCode == KeyEvent.KEYCODE_BACK) && (cose_webview.canGoBack() == false)){
            if (!cose_Flag){
                Toast.makeText(this,"'뒤로'버튼을 한번더 누르시면 종료됩니다.",Toast.LENGTH_SHORT).show();
                cose_Flag = true;
                cose_Handler.sendEmptyMessageDelayed(0,2000);
                return true;
            }else {
                moveTaskToBack(true);
                android.os.Process.killProcess(Process.myPid());
            }
        }
        return super.onKeyDown(keyCode, event);
    }

이게 goback쪽 코드입니다

back을 했을때 뜨는 디바이스 화면입니다.