Package com.vaadin.flow.component.page

Class Page

java.lang.Object
com.vaadin.flow.component.page.Page
All Implemented Interfaces:
Serializable
public class Page extends Object implements Serializable
Represents the web page open in the browser, containing the UI it is connected to.
Since:
1.0
Author:
Vaadin Ltd
See Also:

  • Constructor Details

    • Page

      public Page(UI ui)
      Creates a page instance for the given UI.
      Parameters:
      ui - the UI that this page instance is connected to

  • Method Details

    • setTitle

      public void setTitle(String title)
      Sets the page title. The title is displayed by the browser e.g. as the title of the browser window or tab.

      To clear the page title, use an empty string.

      Parameters:
      title - the page title to set, not null

    • addStyleSheet

      public Registration addStyleSheet(String url)
      Adds the given style sheet to the page and ensures that it is loaded successfully.

      Relative URLs are interpreted as relative to the static web resources directory. So if the url value is "some.js" and src/main/webapp is used as a location for static web resources (which is the default location) then the file system path for the resource should be src/main/webapp/some.js.

      You can prefix the URL with context:// to make it relative to the context path or use an absolute URL to refer to files outside the frontend directory.

      For component related style sheet dependencies, you should use the @StyleSheet annotation.

      Is is guaranteed that style sheet will be loaded before the first page load. For more options, refer to addStyleSheet(String, LoadMode)

      Parameters:
      url - the URL to load the style sheet from, not null
      Returns:
      a registration object that can be used to remove the style sheet

    • addStyleSheet

      public Registration addStyleSheet(String url, LoadMode loadMode)
      Adds the given style sheet to the page and ensures that it is loaded successfully.

      Relative URLs are interpreted as relative to the static web resources directory. So if the url value is "some.js" and src/main/webapp is used as a location for static web resources (which is the default location) then the file system path for the resource should be src/main/webapp/some.js.

      You can prefix the URL with context:// to make it relative to the context path or use an absolute URL to refer to files outside the frontend directory.

      For component related style sheet dependencies, you should use the @StyleSheet annotation.

      Parameters:
      url - the URL to load the style sheet from, not null
      loadMode - determines dependency load mode, refer to LoadMode for details
      Returns:
      a registration object that can be used to remove the style sheet

    • addJavaScript

      public void addJavaScript(String url)
      Adds the given JavaScript to the page and ensures that it is loaded successfully.

      Relative URLs are interpreted as relative to the static web resources directory. So if the url value is "some.js" and src/main/webapp is used as a location for static web resources (which is the default location) then the file system path for the resource should be src/main/webapp/some.js.

      You can prefix the URL with context:// to make it relative to the context path or use an absolute URL to refer to files outside the frontend directory.

      For component related JavaScript dependencies, you should use the @JavaScript annotation.

      Is is guaranteed that script will be loaded before the first page load. For more options, refer to addJavaScript(String, LoadMode)

      Parameters:
      url - the URL to load the JavaScript from, not null

    • addJavaScript

      public void addJavaScript(String url, LoadMode loadMode)
      Adds the given JavaScript to the page and ensures that it is loaded successfully.

      Relative URLs are interpreted as relative to the static web resources directory. So if the url value is "some.js" and src/main/webapp is used as a location for static web resources (which is the default location) then the file system path for the resource should be src/main/webapp/some.js.

      You can prefix the URL with context:// to make it relative to the context path or use an absolute URL to refer to files outside the frontend directory.

      For component related JavaScript dependencies, you should use the @JavaScript annotation.

      Parameters:
      url - the URL to load the JavaScript from, not null
      loadMode - determines dependency load mode, refer to LoadMode for details

    • addJsModule

      public void addJsModule(String url)
      Adds the given external JavaScript module to the page and ensures that it is loaded successfully.

      If the JavaScript modules do not need to be added dynamically, you should use the @JsModule annotation instead.

      Parameters:
      url - the URL to load the JavaScript module from, not null

    • addDynamicImport

      public void addDynamicImport(String expression)
      Adds a dynamic import using a JavaScript expression which is supposed to return a JavaScript Promise.

      No change will be applied on the client side until resulting Promise of the expression is completed. It behaves like other dependencies (addJavaScript(String), addJsModule(String), etc.)

      Parameters:
      expression - the JavaScript expression which return a Promise

    • executeJs

      public PendingJavaScriptResult executeJs(String expression, Object... parameters)
      Asynchronously runs the given JavaScript expression in the browser.

      The expression is executed in an async JavaScript method, so you can utilize await syntax when consuming JavaScript API returning a Promise. The returned PendingJavaScriptResult can be used to retrieve the return value from the JavaScript expression. If a Promise is returned in the JavaScript expression, PendingJavaScriptResult will report the resolved value once it becomes available. If no return value handler is registered, the return value will be ignored.

      Return values from JavaScript can be automatically deserialized into Java objects. All types supported by Jackson for JSON deserialization are supported as return values, including custom bean classes.

      The given parameters will be available to the expression as variables named $0, $1, and so on. All types supported by Jackson for JSON serialization are supported as parameters. Special cases:

      • Element (will be sent as a DOM element reference to the browser if the server-side element instance is attached when the invocation is sent to the client, or as null if not attached)
      • BaseJsonNode (sent as-is without additional wrapping)
      Note that the parameter variables can only be used in contexts where a JavaScript variable can be used. You should for instance do 'prefix' + $0 instead of 'prefix$0' and value[$0] instead of value.$0 since JavaScript variables aren't evaluated inside strings or property names.
      Parameters:
      expression - the JavaScript expression to invoke
      parameters - parameters to pass to the expression
      Returns:
      a pending result that can be used to get a value returned from the expression

    • executeJs

      @Deprecated public PendingJavaScriptResult executeJs(String expression, Serializable[] parameters)
      Deprecated.
      Use executeJs(String, Object...) instead. This method exists only for binary compatibility.
      Executes the given JavaScript expression in the browser.
      Parameters:
      expression - the JavaScript expression to execute
      parameters - parameters to pass to the expression
      Returns:
      a pending result that can be used to get a value returned from the expression

    • getHistory

      public History getHistory()
      Gets a representation of window.history for this page.
      Returns:
      the history representation

    • reload

      public void reload()
      Reloads the page in the browser.

    • addBrowserWindowResizeListener

      public Registration addBrowserWindowResizeListener(BrowserWindowResizeListener resizeListener)
      Adds a new BrowserWindowResizeListener to this UI. The listener will be notified whenever the browser window within which this UI resides is resized.
      Parameters:
      resizeListener - the listener to add, not null
      Returns:
      a registration object for removing the listener
      See Also:

    • open

      public void open(String url)
      Opens the given url in a new tab.
      Parameters:
      url - the URL to open.

    • open

      public void open(String url, String windowName)
      Opens the given URL in a window with the given name.

      The supplied windowName is used as the target name in a window.open call in the client. This means that special values such as "_blank", "_self", "_top", "_parent" have special meaning. An empty or null window name is also a special case.

      "", null and "_self" as windowName all causes the URL to be opened in the current window, replacing any old contents. For downloadable content you should avoid "_self" as "_self" causes the client to skip rendering of any other changes as it considers them irrelevant (the page will be replaced by the response from the URL). This can speed up the opening of a URL, but it might also put the client side into an inconsistent state if the window content is not completely replaced e.g., if the URL is downloaded instead of displayed in the browser.

      "_blank" as windowName causes the URL to always be opened in a new window or tab (depends on the browser and browser settings).

      "_top" and "_parent" as windowName works as specified by the HTML standard.

      Any other windowName will open the URL in a window with that name, either by opening a new window/tab in the browser or by replacing the contents of an existing window with that name.

      Parameters:
      url - the URL to open.
      windowName - the name of the window.

    • setLocation

      public void setLocation(String uri)
      Navigates this page to the given URI. The contents of this page in the browser is replaced with whatever is returned for the given URI.
      Parameters:
      uri - the URI to show

    • setLocation

      public void setLocation(URI uri)
      Navigates this page to the given URI. The contents of this page in the browser is replaced with whatever is returned for the given URI.
      Parameters:
      uri - the URI to show

    • retrieveExtendedClientDetails

      public void retrieveExtendedClientDetails(Page.ExtendedClientDetailsReceiver receiver)
      Obtain extended client side details, such as time screen and time zone information, via callback. If already obtained, the callback is called directly. Otherwise, a client-side roundtrip will be carried out.
      Parameters:
      receiver - the callback to which the details are provided

    • fetchCurrentURL

      public void fetchCurrentURL(SerializableConsumer<URL> callback)
      Retrieves the current url from the browser. The URL is fetched from the browser in another request asynchronously and passed to the callback. The URL is the full URL that the user sees in the browser (including hash #) and works even when client side routing is used or there is a reverse proxy between the client and the server.

      In case you need more control over the execution you can use executeJs(String, Object...) by passing return window.location.href.

      NOTE: the URL is not escaped, use URL.toURI() to escape it.

      Parameters:
      callback - to be notified when the url is resolved.

    • fetchPageDirection

      public void fetchPageDirection(SerializableConsumer<Direction> callback)
      Retrieves document.dir of the current UI from the browser and passes it to the callback parameter. If the document.dir has not been set explicitly, then Direction.LEFT_TO_RIGHT will be the fallback value.

      Note that direction is fetched from the browser in an asynchronous request and passed to the callback.

      In case you need more control over the execution you can use executeJs(String, Object...) by passing return document.dir.

      Parameters:
      callback - to be notified when the direction is resolved.