Package org.zkoss.zk.ui

Class Components

java.lang.Object
org.zkoss.zk.ui.Components
public class Components extends Object
Utilities to access Component.
Author:
tomyeh

  • Field Details

    • EXECUTION_PROXY

      public static final org.zkoss.zk.ui.Components.Exec EXECUTION_PROXY
      Execution Proxy

    • REQUEST_SCOPE_PROXY

      public static final org.zkoss.zk.ui.Components.RequestScope REQUEST_SCOPE_PROXY
      Request Scope Proxy

  • Constructor Details

    • Components

      protected Components()

  • Method Details

    • getParentIdSpace

      public static IdSpace getParentIdSpace(IdSpace idspace)
      Returns the parent of the ID space, or null if not found.
      Since:
      5.0.0

    • sort

      public static void sort(List<? extends Component> list, Comparator<? super Component> cpr)
      Sorts the components in the list.

      Note: you cannot use Collections.sort(java.util.List<T>) to sort Component.getChildren() because Collections.sort might cause some replicated item in the list.

      See Also:

    • sort

      public static void sort(List<? extends Component> list, int from, int to, Comparator<? super Component> cpr)
      Sorts the components in the list.
      Parameters:
      list - the list to be sorted
      from - the index of the first element (inclusive) to be sorted
      to - the index of the last element (exclusive) to be sorted
      cpr - the comparator to determine the order of the list.
      Since:
      3.5.0

    • replace

      public static void replace(Component oldc, Component newc)
      Replaces a component with another.
      Parameters:
      oldc - the component to remove.
      newc - the component to add
      Throws:
      IllegalArgumentException - if oldc's parent and page are both null.
      Since:
      3.5.2

    • replaceChildren

      public static void replaceChildren(Component parent, Collection<Component> newChildren)
      Replaces all children of the specified component. It is the same as 
      parent.getChildren().clear();
parent.getChildren().addAll(newChildren);
      Since:
      3.5.2

    • getRoot

      public static Component getRoot(Component comp)
      Returns the root component of the specified one. Notice that it could return comp, if it is already a root component (or it is null).
      Since:
      3.6.3

    • isAncestor

      public static boolean isAncestor(Component node1, Component node2)
      Tests whether node1 is an ancestor of node 2. If node1 and node2 is the same, true is returned.

    • removeAllChildren

      public static void removeAllChildren(Component comp)
      Removes all children of the specified component. It is the same as comp.getChildren().clear().

    • getDefinitionByDeviceType

      public static final ComponentDefinition getDefinitionByDeviceType(String deviceType, Class cls)
      Returns the component definition of the specified class in all language of the specified device, or null if not found
      Parameters:
      deviceType - the device type (Device), such as ajax. It cannot be null.
      cls - the implementation class of the component.
      Since:
      5.0.0

    • isRealVisible

      public static boolean isRealVisible(Component comp)
      Returns whether this component is real visible (all its parents are visible).

      Note: true is returned if comp is null. In other words, it can be used to examine parent's real visibility even if it is a root component, such as Components.isRealVisible(getParent()).

      See Also:

    • getVisibleChildren

      public static Collection<Component> getVisibleChildren(Component comp)
      Returns a collection of visible children.

      The performance of the returned collection's size() is NO GOOD.

    • getScope

      public static final int getScope(String scope)
      Converts a string to an integer that can be used to access Component.getAttribute(String, int)

    • scopeToString

      public static final String scopeToString(int scope)
      Converts an integer to the string representing the scope.
      Parameters:
      scope - one of Component.COMPONENT_SCOPE, Component.SPACE_SCOPE, Component.PAGE_SCOPE, Component.DESKTOP_SCOPE, Component.SESSION_SCOPE, Component.REQUEST_SCOPE, and Component.APPLICATION_SCOPE.

    • componentToPath

      public static final String componentToPath(Component comp, Component ref)
      Converts a component to a path (relevant to another component). It is usefully to implement a serializable component that contains a reference to another component. In this case, we can not serializes the reference directly (otherwise, another component will be created, when deserialized).

      Rather, it is better to store the path related, and then restore it back to a component by calling pathToComponent(java.lang.String, org.zkoss.zk.ui.Component).

      Parameters:
      comp - the component to be converted to path. It cannot be null.
      ref - the component used to generated the path from. It cannot be null.
      Returns:
      the path. Notice that you have to use pathToComponent(java.lang.String, org.zkoss.zk.ui.Component) to convert it back.
      Throws:
      UnsupportedOperationException - if we cannot find a path to the component to write.
      Since:
      3.0.0

    • pathToComponent

      public static final Component pathToComponent(String path, Component ref)
      Converts a path, generated by componentToPath(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component), to a component.
      Parameters:
      ref - the component used to generated the path from. It cannot be null. It is the same as the one when calling componentToPath(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component).
      Since:
      3.0.0

    • isImplicit

      public static boolean isImplicit(String id)
      Returns whether the given id is an implicit ZK object id.
      Parameters:
      id - Component id
      Returns:
      whether the given name is a implicit object.
      Since:
      3.5.2

    • getImplicitNames

      public static Collection<String> getImplicitNames()
      Returns a readonly collection of the names of the implicit objects.
      Since:
      6.0.0

    • getImplicit

      public static Object getImplicit(Page page, Component comp, String name)
      Returns the implicit object of the specified name, or null if not found.

      Notice that it does check for the current scope (Scopes.getCurrent(org.zkoss.zk.ui.Page)). Rather, Scopes.getImplicit(java.lang.String, java.lang.Object) depends on this method.

      Parameters:
      page - the page. If page is null and comp is not, comp.getPage() is assumed
      Since:
      5.0.0
      See Also:

    • getImplicit

      public static Object getImplicit(Component comp, String name)
      Returns the implicit object of the specified name, or null if not found.

      It is the same as getImplicit(null, comp, name).

      Since:
      3.6.0

    • getImplicit

      public static Object getImplicit(Page page, String name)
      Returns the implicit object of the specified name, or null if not found.

      It is the same as getImplicit(page, null, name).

      Since:
      3.6.0

    • getComposer

      public static Composer getComposer(Component comp)
      Returns the composer object, or null if not found.
      Since:
      7.0.3

    • smartUpdate

      public static void smartUpdate(Component comp, String key, Object value, boolean append)
      Adds the smartUpdate command to the specific component.
      Since:
      7.0.3

    • getCurrentPage

      public static Page getCurrentPage(Component comp)
      Returns the page of the give component, or the current page if the component is null or it doesn't belong to any page. The current page is retrieved by ExecutionCtrl.getCurrentPage() or the current execution. This method returns null if no execution or no current page at all.
      Parameters:
      comp - the component to retrieve the page. Ignored if null.
      Since:
      6.0.0