Docs Help

Terms, Icons, and Labels

Many classes have shortcut names used when creating (instantiating) a class with a configuration object. The shortcut name is referred to as an alias (or xtype if the class extends Ext.Component). The alias/xtype is listed next to the class name of applicable classes for quick reference.

Access Levels

Framework classes or their members may be specified as private or protected. Else, the class / member is public. Public, protected, and private are access descriptors used to convey how and when the class or class member should be used.

Member Types

Member Syntax

Below is an example class member that we can disect to show the syntax of a class member (the lookupComponent method as viewed from the Ext.button.Button class in this case).

lookupComponent ( item ) : Ext.Component
protected

Called when a raw config object is added to this container either during initialization of the items config, or when new items are added), or {@link #insert inserted.

This method converts the passed object into an instanced child component.

This may be overridden in subclasses when special processing needs to be applied to child creation.

Parameters

item :  Object

The config object being added.

Returns
Ext.Component

The component to be added.

Let's look at each part of the member row:

Member Flags

The API documentation uses a number of flags to further commnicate the class member's function and intent. The label may be represented by a text label, an abbreviation, or an icon.

Class Icons

- Indicates a framework class

- A singleton framework class. *See the singleton flag for more information

- A component-type framework class (any class within the Ext JS framework that extends Ext.Component)

- Indicates that the class, member, or guide is new in the currently viewed version

Member Icons

- Indicates a class member of type config

- Indicates a class member of type property

- Indicates a class member of type method

- Indicates a class member of type event

- Indicates a class member of type theme variable

- Indicates a class member of type theme mixin

- Indicates that the class, member, or guide is new in the currently viewed version

Class Member Quick-Nav Menu

Just below the class name on an API doc page is a row of buttons corresponding to the types of members owned by the current class. Each button shows a count of members by type (this count is updated as filters are applied). Clicking the button will navigate you to that member section. Hovering over the member-type button will reveal a popup menu of all members of that type for quick navigation.

Getter and Setter Methods

Getting and setter methods that correlate to a class config option will show up in the methods section as well as in the configs section of both the API doc and the member-type menus just beneath the config they work with. The getter and setter method documentation will be found in the config row for easy reference.

History Bar

Your page history is kept in localstorage and displayed (using the available real estate) just below the top title bar. By default, the only search results shown are the pages matching the product / version you're currently viewing. You can expand what is displayed by clicking on the button on the right-hand side of the history bar and choosing the "All" radio option. This will show all recent pages in the history bar for all products / versions.

Within the history config menu you will also see a listing of your recent page visits. The results are filtered by the "Current Product / Version" and "All" radio options. Clicking on the button will clear the history bar as well as the history kept in local storage.

If "All" is selected in the history config menu the checkbox option for "Show product details in the history bar" will be enabled. When checked, the product/version for each historic page will show alongside the page name in the history bar. Hovering the cursor over the page names in the history bar will also show the product/version as a tooltip.

Search and Filters

Both API docs and guides can be searched for using the search field at the top of the page.

On API doc pages there is also a filter input field that filters the member rows using the filter string. In addition to filtering by string you can filter the class members by access level, inheritance, and read only. This is done using the checkboxes at the top of the page.

The checkbox at the bottom of the API class navigation tree filters the class list to include or exclude private classes.

Clicking on an empty search field will show your last 10 searches for quick navigation.

API Doc Class Metadata

Each API doc page (with the exception of Javascript primitives pages) has a menu view of metadata relating to that class. This metadata view will have one or more of the following:

Expanding and Collapsing Examples and Class Members

Runnable examples (Fiddles) are expanded on a page by default. You can collapse and expand example code blocks individually using the arrow on the top-left of the code block. You can also toggle the collapse state of all examples using the toggle button on the top-right of the page. The toggle-all state will be remembered between page loads.

Class members are collapsed on a page by default. You can expand and collapse members using the arrow icon on the left of the member row or globally using the expand / collapse all toggle button top-right.

Desktop -vs- Mobile View

Viewing the docs on narrower screens or browsers will result in a view optimized for a smaller form factor. The primary differences between the desktop and "mobile" view are:

Viewing the Class Source

The class source can be viewed by clicking on the class name at the top of an API doc page. The source for class members can be viewed by clicking on the "view source" link on the right-hand side of the member row.

GXT 4.x


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Dom Manipulation

Working with the HTML Document Object Model. Finding and working with elements in the DOM.

Reference

Finding widgets elements

Find the widgets element

  • Using GWT

      Element element = gwtWidget.getElement();
    
  • Using GXT

      XElement element = gxtWidget.getElement();
    
      Element element = gxtWidget.getElement();
    

Casting the widgets element

Casting

  • Using GWT

      Element element = gwtWidget.getElement().cast();
    
  • Using GXT

      XElement element = gxtWidget.getElement().cast();
    
      // Other options
      Element element = gwtWidget.getElement();
      // as factory
      XElement xelement1 = XElement.as(element);
      // casting
      XElement xelement2 = element.cast();
    

Finding Elements in the DOM

Find elements in the DOM using com.sencha.gxt.core.client.dom.DomQuery.

Find element by id

  • Using GWT

      DOM.getElementById("main");
    
  • Using GXT

      DomQuery.select("#main").getItem(0);
    
      gxtWidget.getElement().select("#main").getItem(0);
    

Find element by class

  • Using GXT

      DomQuery.select(".visible").getItem(0);
    
      gxtWidget.getElement().select(".visible").getItem(0);
    

Find elements by class

  • Using GXT

      DomQuery.select(".visible");
    
      gxtWidget.getElement().select(".visible");
    

Find element by tag

  • Using GWT

      Document.get().getElementsByTagName("div").getItem(0);
    
  • Using GXT

      DomQuery.select("div").getItem(0);
    
      gxtWidget.getElement().select("div").getItem(0);
    

Find elements by tag

  • Using GWT

      Document.get().getElementsByTagName("div").getItem(0);
    
  • Using GXT

      DomQuery.select("div");
    
      gxtWidget.getElement().select("div");
    

Find element by name

  • Using GXT

      DomQuery.select("[name='form']");
    
      gxtWidget.getElement().select("[name='form']");
    

Find elements by combination of above

  • Using GWT with GXT

      DomQuery.select("#main div:first .visible");
    
      gxtWidget.getElement().select("#main div:first .visible");
    

Iterate over a list of elements

  • Using GXT

      NodeList<Element> elements = DomQuery.select(".visible");
      for (int i=0; i < elements.getLength(); i++) {
        Element element = elements.getItem(i);
      }
    
      NodeList<Element> elements = gxtWidget.getElement().select(".visible");
      for (int i=0; i < elements.getLength(); i++) {
        Element element = elements.getItem(i);
      }
    

Access the first child

  • Using GWT with GXT

      elements.getItem(0);
    

Find out whether an element has children elements

  • Using GWT with GXT

      elements.getLength() == 0
    

Manipulating DOM

Create an element

  • Using GWT

      DivElement element = Document.get().createDivElement();
    

Create an element and set its contents

  • Using GWT

      DivElement element = Document.get().createDivElement();
      element.setInnerHTML("<p>A quick brown <em>fox</em>.</p>");
    

Add an element to a parent

  • Using GWT

      Document.get().getBody().appendChild(element);
    

Remove an element from its parent

  • Using GWT

      DivElement element = Document.get().createDivElement();
      Document.get().getBody().appendChild(element);
      element.removeFromParent();
    

Regular Expressions

com.google.gwt.regexp.shared.RegExp Javadoc

RegExp

  • Using GWT

      String email = "no-reply@[email protected]";
      Pattern pattern = Pattern.compile("(@)");
      Matcher matcher = pattern.matcher(email);
    

RegExp Iterating

  • Using GWT

      String email = "no-reply@[email protected]";
      RegExp regExp = RegExp.compile("(@)");
      MatchResult matcher = regExp.exec(email);
    

Exceptions

Throw an exception

  • Using Java and GWT

      throw new Exception("Intruder Alert!!");    
    

Catch an exception

  • Using Java and GWT

      try {
        Integer.parseInt("three");
      } catch (NumberFormatException e) {
        e.printStackTrace();
      }
    

Catch Uncaught Exceptions

  • Using GWT

      GWT.setUncaughtExceptionHandler(new UncaughtExceptionHandler() {
        @Override
        public void onUncaughtException(Throwable e) {
          e.printStackTrace();
        }
      });
    

DOM Event handling

Attach an event handler

It is recommended to use the widget framework to avoid memory leaks.

  • Using GWT

      // Use the widget framework, this can cause memory leaks
      Element element = DOM.getElementById("main");
      Event.sinkEvents(element, Event.ONCLICK);
      DOM.setEventListener(element, new EventListener() {          
        @Override
        public void onBrowserEvent(Event event) {
              if (Event.ONCLICK == event.getTypeInt()) {
                System.out.println("clicked");
              }
        }
      });
    

Remove an event handler

It is recommended to use the widget framework to avoid memory leaks.

  • Using GWT

      DOM.setEventListener(getElement(), null);
    

Listen to all events

Use a Native Prevew Hander to listen for all the DOM events.

  • Using GWT

      Event.addNativePreviewHandler(new NativePreviewHandler() {
        public void onPreviewNativeEvent(final NativePreviewEvent event) {
          final int eventType = event.getTypeInt();
          switch (eventType) {
            case Event.ONMOUSEMOVE:
              break;
            case Event.ONCLICK:
              break;
            default:
              break;
          }
        }
      });
    

Timing

Schedule a future event

Consider using Scheduler.get() to schedule a future execution.

  • Using GWT

      Timer timer = new Timer() {
        @Override
        public void run() {
              System.out.print("the future is here");
        }
      };
      timer.schedule(1000);
    

Schedule on the next event loop

com.google.gwt.core.client.Scheduler Javadoc - see more scheduler options

  • Using GWT

      // This will schedule before scheduleFinally commands.
      Scheduler.get().scheduleDeferred(new ScheduledCommand() {
        @Override
        public void execute() {
              System.out.println("I'm next");
        }
      });
    

Schedule at the end of the event loop

com.google.gwt.core.client.Scheduler Javadoc - see more scheduler options

  • Using GWT

      // This will schedule after other scheduled deferred commands.
      Scheduler.get().scheduleFinally(new ScheduledCommand() {
        @Override
        public void execute() {
              System.out.print("the future is here");
        }
      });
    

Measure the execution time of a function

  • Using GWT

      long watch = System.currentTimeMillis();
      method();
      long elapsed = System.currentTimeMillis() - watch;
      System.out.println(elapsed);
    

HTML attributes

Get HTML attribute

  • Using GWT

      element.getAttribute("href");
    

Set HTML attribute

  • Using GWT

      element.setAttribute("playable", "true");
    

Remove HTML attribute

  • Using GWT

      element.removeAttribute("playable");
    

Check if HTML attribute exists

  • Using GWT

      element.hasAttribute("playable");
    

CSS classes

Add CSS class

  • Using GWT

      element.setClassName("new-class");        
    

Remove CSS class

  • Using GWT

      element.removeClassName("new-class");
    

Ajax

Request data via XMLHttpRequest

  • Using GWT

      RequestBuilder request = new RequestBuilder(RequestBuilder.GET, "/data.json");
      request.setCallback(new RequestCallback() {
        @Override
        public void onResponseReceived(Request request, Response response) {
              System.out.println(response.getText());
        }
    
        @Override
        public void onError(Request request, Throwable exception) {
              exception.printStackTrace();
        }
      });    
    

JQuery like

React to document finishing loading

  • Using GWT

      public class ProjectEntryPoint implements EntryPoint {
        @Override
        public void onModuleLoad() {
              System.out.println("loaded");
        }
      }        
    

Node lookup

com.sencha.gxt.core.client.dom.DomQuery Javadoc - See more options

  • Using GXT

      NodeList<Element> elements = DomQuery.select("input");
    
      NodeList<Element> elements = gxtWidget.getElement().select("input");
    

Node creation

  • Using GWT

      ImageElement pic = Document.get().createImageElement();
      pic.addClassName("avatar");
      pic.setSrc("myPic.jpg");
      Document.get().getBody().appendChild(pic);            
    

Event handling

It is recommended to use the widget framework to avoid memory leaks.

  • Using GWT

      // Use the widget framework, this can cause memory leaks
      Element element = DOM.getElementById("main");
      Event.sinkEvents(element, Event.ONCLICK);
      DOM.setEventListener(element, new EventListener() {          
        @Override
        public void onBrowserEvent(Event event) {
              if (Event.ONCLICK == event.getTypeInt()) {
                System.out.println("clicked");
              }
        }
      });    
    

Relative nodes

  • Using GWT

      Element element = DOM.getElementById("main");
      Node parent = element.getParentNode();
      Node child = parent.getChild(0);
      // Or getting the parent Element
          Element parentElement = element.getParentElement();
          // Or getting the first child element
          Element childElement = parentElement.getFirstChildElement();        
    

Children

  • Using GWT

      Element element = DOM.getElementById("main");
      NodeList<Node> children = element.getChildNodes();
    

Clone

  • Using GWT

      Element element = DOM.getElementById("main");
      Node clonedElement = element.cloneNode(true);
    

GXT 4.x