I put the dialog display directly in onSubscribe and then hide it in onComplete or onError. But I wrote that no matter which interface the dialog interface occupies the full screen, how can it only be displayed in a specified area, such as the picture is a main interface, the following are four toggle buttons, want to display the dialog in the red area.

public abstract class HttpCallback<T> implements Observer<BaseResponse<T>> {
    public static final String TAG = HttpCallback.class.getCanonicalName();

    private WeakReference<Activity> mActivity;

    private boolean mShow;
    private boolean mCancelable = false;

    private boolean hasError = true;
    private AlertDialog mDialog;

    public HttpCallback(Activity activity) {
        mActivity = new WeakReference<>(activity);
    }

    @Override
    public void onSubscribe(Disposable d) {
        if (mShow) {
            showDialog();//,onSubscribe,showProgresstrue
            Log.d(TAG, "onSubscribe: 1103");
        }else{
            Log.d(TAG, "onSubscribe: 1103");
        }
    }

    @Override
    public void onNext(BaseResponse<T> t) {
        int code = t.getCode();  // 0 ,  1  ,  -1 token
//        int code=-1;
        if (code == RequestUrl.CODE_SUCCESS) {
            hasError = false;
            onSuccess(t.getData(), t.getMsg());
        } else if (code == RequestUrl.CODE_TOKEN_EXPIRE) {
            toLogin();//token,
        } else {
            ToastUtils.showMessage(t.getMsg());
            onFailure();
        }
    }

    @Override
    public void onError(Throwable e) {
        if (mDialog != null)
            mDialog.dismiss();
        if (e instanceof SocketTimeoutException) {
            // 
            onError(e, ErrorStatus.HTTP_TIMEOUT);
        } else if (e instanceof ConnectException || e instanceof UnknownHostException) {
            // 
            onError(e, ErrorStatus.HTTP_UNCONNECTED);
        } else if (e instanceof HttpException) {
            // 
//            onError(e, ErrorStatus.HTTP_EXCEPTION.setErrorCode(((HttpException) e).code()));
            onError(e, ErrorStatus.HTTP_EXCEPTION);
        } else if (e instanceof JsonSyntaxException || e instanceof JSONException) {
            // 
            onError(e, ErrorStatus.DATA_EXCEPTION);
        } else {
            // 
            onError(e, ErrorStatus.OTHER_EXCEPTION);
        }
        onFinish(hasError);
    }

    private void onError(Throwable e, final ErrorStatus otherException) {
        if (e != null) {
            e.printStackTrace();
        }

        mActivity.get().runOnUiThread(new Runnable() {
            @Override
            public void run() {
                ToastUtils.showMessage(otherException.getErrorMessage(), Toast.LENGTH_SHORT);
            }
        });
    }

    @Override
    public void onComplete() {
        if (mDialog != null)
            mDialog.dismiss();
        onFinish(hasError);
    }

    public abstract void onSuccess(T t, String msg);

    //token
    public void onFailure() {

    }

    //token
    public void onTokenExpired() {

    }

    public void onFinish(boolean hasError) {
    }

    protected void showProgress(boolean show) {
        mShow = show;
    }

    public void setCancelable(boolean cancelable) {
        mCancelable = cancelable;
    }
    
    private void showDialog() {
        mDialog = new AlertDialog.Builder(mActivity.get()).create();
        mDialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
        mDialog.setCancelable(false);
        mDialog.show();
        Window window = mDialog.getWindow();
        window.getDecorView().setPadding(0, 0, 0, 0);
        window.setGravity(Gravity.CENTER);
        window.setContentView(R.layout.loading);
        WindowManager.LayoutParams lp = window.getAttributes();
        lp.width = WindowManager.LayoutParams.FILL_PARENT;
        lp.height = WindowManager.LayoutParams.FILL_PARENT;
        window.setAttributes(lp);
    }

    private void toLogin() {
//        ToastUtils.showLongMessage(",");
        AlertDialog.Builder builder = new AlertDialog.Builder(mActivity.get());
        builder.setTitle("")
                .setMessage(",")
                .setCancelable(false)
                .setPositiveButton("", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        UserManager.getInstance().logout();//
                        Intent loginIntent = new Intent(mActivity.get(), ThirdLoginActivity.class);//token,
                        loginIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
//            loginIntent.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
                        mActivity.get().startActivity(loginIntent);
                    }
                }).show();
    }
}