java.lang.NoSuchFieldException: FLAG_NEEDS_MENU_KEY

原因解析：

	/**
     * Returns a {@code Field} object that reflects the specified public member
     * field of the class or interface represented by this {@code Class}
     * object. The {@code name} parameter is a {@code String} specifying the
     * simple name of the desired field.
     *
     * 
 The field to be reflected is determined by the algorithm that
     * follows.  Let C be the class or interface represented by this object:
     *
     * 

     * 
 If C declares a public field with the name specified, that is the
     *      field to be reflected.
     * 
 If no field was found in step 1 above, this algorithm is applied
     *      recursively to each direct superinterface of C. The direct
     *      superinterfaces are searched in the order they were declared.
     * 
 If no field was found in steps 1 and 2 above, and C has a
     *      superclass S, then this algorithm is invoked recursively upon S.
     *      If C has no superclass, then a {@code NoSuchFieldException}
     *      is thrown.
     * 
     *
     * 
 If this {@code Class} object represents an array type, then this
     * method does not find the {@code length} field of the array type.
     *
     * @param name the field name
     * @return the {@code Field} object of this class specified by
     *         {@code name}
     * @throws NoSuchFieldException if a field with the specified name is
     *         not found.
     * @throws NullPointerException if {@code name} is {@code null}
     * @throws SecurityException
     *         If a security manager, s, is present and
     *         the caller's class loader is not the same as or an
     *         ancestor of the class loader for the current class and
     *         invocation of {@link SecurityManager#checkPackageAccess
     *         s.checkPackageAccess()} denies access to the package
     *         of this class.
     *
     * @since JDK1.1
     * @jls 8.2 Class Members
     * @jls 8.3 Field Declarations
     */
    // Android-changed: Removed SecurityException
    public Field getField(String name)
        throws NoSuchFieldException {
        if (name == null) {
            throw new NullPointerException("name == null");
        }
        Field result = getPublicFieldRecursive(name);
        if (result == null) {
            throw new NoSuchFieldException(name);
        }
        return result;
    }

在 getField(String name) 的源码中可以看出

如果具有指定名称的字段为未找到就会报NoSuchFieldException。

解决办法，把代码放入 try{}catch(){} 中，抛出 NoSuchFieldException 异常。

解决方案：

		// 设置没有实体菜单键的机器显示虚拟菜单键
        try {
            window.addFlags(WindowManager.LayoutParams.class.getField("FLAG_NEEDS_MENU_KEY").getInt(null));
        } catch (NoSuchFieldException e) {
            // Ignore since this field won't exist in most versions of Android
        } catch (Exception e) {
            e.printStackTrace();
        }