操作栏标题返回null

Question

我使用下面的代码来对齐操作栏标题中心。

  try {
                int titleId = 0;
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
                    titleId = getResources().getIdentifier("action_bar_title",
                            "id", "android");
                } else {
                    // This is the id is from your app's generated R class when
                    // ActionBarActivity is used
                    // for SupportActionBar
                    titleId = R.id.action_bar_title;
                }

                // Final check for non-zero invalid id
                if (titleId > 0) {
                    TextView titleTextView = (TextView) findViewById(titleId);

                    DisplayMetrics metrics = getResources().getDisplayMetrics();

                    // Fetch layout parameters of titleTextView
                    // (LinearLayout.LayoutParams : Info from HierarchyViewer)
                    LinearLayout.LayoutParams txvPars = (android.widget.LinearLayout.LayoutParams)titleTextView
                            .getLayoutParams();
                    txvPars.gravity = Gravity.CENTER_HORIZONTAL;
                    txvPars.width = metrics.widthPixels;
                    titleTextView.setLayoutParams(txvPars);
                    titleTextView.setSingleLine(false);
                    titleTextView.setMaxLines(2);
                    titleTextView.setPadding(5, 5, 5, 5);
                    titleTextView.setTextSize(17);
                    titleTextView.setGravity(Gravity.CENTER);
                }

            } catch (Exception e) {
                Utility.printException(e);
            }

此titleTextView TextView返回null。

 TextView titleTextView = (TextView) findViewById(titleId);

我正在使用ActionBarActivity。 app compact support library v7。

Theme.AppCompact.light

 <style name="AppBaseTheme" parent="Theme.AppCompat.Light">
        <item name="windowActionBar">false</item>
    </style>

    <style name="AppTheme" parent="AppBaseTheme">
        <item name="actionOverflowMenuStyle">@style/OverflowMenu</item>
        <!-- <item name="actionBarStyle">@style/Theme.MyApp.ActionBar</item> -->
    </style>


    <style name="OverflowMenu" parent="Widget.AppCompat.PopupMenu.Overflow">

        <!-- Required for pre-Lollipop. -->
        <item name="overlapAnchor">false</item>

        <!-- Required for Lollipop. -->
        <!-- <item name="android:overlapAnchor">false</item> -->
    </style>