Android状态栏高度、虚拟操作栏高度

public class ScreenUtils {

    private ScreenUtils() {
        throw new AssertionError();
    }

    /**
     * dp单位转成px
     *
     * @param context context
     * @param dp      dp值
     * @return px值
     */
    public static int dp2px(Context context, int dp) {
        return (int) (dp * context.getResources().getDisplayMetrics().density);
    }

    /**
     * 获取屏幕宽度
     */
    public static int getScreenWidth(Context context) {
        DisplayMetrics dm = context.getResources().getDisplayMetrics();
        return dm.widthPixels;
    }

    /**
     * 获取屏幕高度
     */
    public static int getScreenHeight(Context context) {
        DisplayMetrics dm = context.getResources().getDisplayMetrics();
        return dm.heightPixels;
    }

    /**
     * 获取状态栏高度
     */
    public static int getStatusBarHeight(Context context) {
        // 一般是25dp
        int height = dp2px(context, 20);
        LogUtil.i("common statusBar height:" + height);
        //获取status_bar_height资源的ID
        int resourceId = context.getResources().getIdentifier("status_bar_height", "dimen", "android");
        if (resourceId > 0) {
            height = context.getResources().getDimensionPixelSize(resourceId);
            LogUtil.i("real statusBar height:" + height);
        }
        LogUtil.i("finally statusBar height:" + height);
        return height;
    }

    /**
     * 虚拟操作拦（home等）是否显示
     */
    public static boolean isNavigationBarShow(Activity activity) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) {
            Display display = activity.getWindowManager().getDefaultDisplay();
            Point size = new Point();
            Point realSize = new Point();
            display.getSize(size);
            display.getRealSize(realSize);
            return realSize.y != size.y;
        } else {
            boolean menu = ViewConfiguration.get(activity).hasPermanentMenuKey();
            boolean back = KeyCharacterMap.deviceHasKey(KeyEvent.KEYCODE_BACK);
            if (menu || back) {
                return false;
            } else {
                return true;
            }
        }
    }

    /**
     * 获取虚拟操作拦（home等）高度
     */
    public static int getNavigationBarHeight(Activity activity) {
        if (!isNavigationBarShow(activity))
            return 0;
        int height = 0;
        Resources resources = activity.getResources();
        //获取NavigationBar的高度
        int resourceId = resources.getIdentifier("navigation_bar_height", "dimen", "android");
        if (resourceId > 0)
            height = resources.getDimensionPixelSize(resourceId);
        LogUtil.i("NavigationBar的高度:" + height);
        return height;
    }
}