Tuesday, August 21, 2012

Custom Callouts in the SharePoint 2013 Metro UI, Part 3: the CalloutManager

Previous: Custom Callouts in the SharePoint 2013 Metro UI, Part 2: Actions
Back to contents.


CalloutManager allows to get or create an instance of the callout and manage its state.


How to Get a Callout

If you need to manage already created callout you have to get a reference to the desired instance. The CalloutManager has several methods to do it.


getFromLaunchPoint

This method allows to get an instance of the callout from its launch point. The only argument is the DOM element that is used as a launch point for the desired callout:
// choose the launch point HTML element
var launchPoint = document.getElementById('calloutDiv');
// get the callout
var callout = CalloutManager.getFromLaunchPoint(launchPoint);

If there's no defined callout for the specified launch point the error will be raised.


getFromLaunchPointIfExists

It's the variation of the getFromLaunchPoint (see above) method. The only difference is that there will be no error if the callout isn't founded. In that case the method simply returns null. it allows to check for the existence of the callout instance silently.

// get the callout
var callout = CalloutManager.getFromLaunchPointIfExists(launchPoint);
if (callout == null)
{
   // create
}

getFromCalloutDescendant

This method allows to get a callout instance from the DOM element located inside it's structure. It allows for example to get the callout from its content. The only argument is the DOM element. If the chosen DOM element is not inside the callout or the callout is not found for the some reason the error will be raised.

// choose the descendant HTML element
var descendant = document.getElementById('descendantDiv');

// get the callount
var callout = CalloutManager.getFromCalloutDescendant(descendant);

How to Create a Callout

There are two methods to create a callout. Both methods accept a callout creation options object and return the created callout instance. For the details of the creation see the first article of the series.


createNew

The method createNew which allows to create a callout is described in the first part of this series.


createNewIfNecessary

The method createNewIfNecessary is almost identical to the createNew but creates the callout only if there's no callout for the target launch point already. If there's a callout it will be returned instead of the creation of the new one.

var callout = CalloutManager.createNewIfNecessary(calloutOptions);

How to Remove a Callout

If you need to remove the callout you need to pass it to the remove method of the CalloutManager:

// get the callout
var launchPoint = document.getElementById('calloutDiv');
var callout = CalloutManager.getFromLaunchPoint(launchPoint);
// remove
CalloutManager.remove(callout);

How to Enumerate All Callouts

If you need to get all the defined callouts you can use the forEach method of the CalloutManager:

// close all the callouts on the page
CalloutManager.forEach(function(callout) {
   // close the current callout
   callout.close();
   }
});

You have to specify a function to apply for each callout. The only argument of this function is the callout instance currently being processed.


How to Close All Opened Callouts

The previous section shows how you can close all the callouts enumerating them by forEach method. But for this particular task the CalloutManager has the helper shortcut function - closeAll:

// close all the callouts;
var isAtLeastOneCalloutClosed = CalloutManager.closeAll();

This function return true if at least one callout was closed.


Previous: Custom Callouts in the SharePoint 2013 Metro UI, Part 2: Actions
Back to contents.

Thursday, August 2, 2012

Custom Callouts in the SharePoint 2013 Metro UI, Part 2: Actions

Previous: Custom Callouts in the SharePoint 2013 Metro UI, Part 1: Basics

Back to contents.

Next: Custom Callouts in the SharePoint 2013 Metro UI, Part 3: CalloutManager


As we can see from the previous part of this series, you can define a set of menu items in your custom callout. These items are called actions.

To define a simple action, you need to:

  1. Configure action creation options
  2. Create an action instance
  3. Add the created instance to the callout

Configure action creation options

Action creation options are being configured via CalloutActionOptions object.

// configure callout action options
var actionOptions = new CalloutActionOptions();
actionOptions.text = 'Action 1';
actionOptions.onClickCallback = function(event, action)
{ 
    // do some work
};

And here’s the result (for the callout creation see the previous article):

Here we’ve defined the required minimum of options – the text and the click event handler.

text

The text is required option. It’s a string.

onClickCallback

It’s the function that handles the action click event. It is required if your action is simple and it doesn’t have any menu items (see below for the menu action details). This function receives two arguments. First argument is the standard HTML DOM event caused by the click on the action. The second parameter is the action itself:

actionOptions.onClickCallback = function(evt, action)
{ 
    // get the event data
    alert(evt.clientX + ' ' + evt.clientY);

    // get the action text
    alert(action.getText());
};

Create an action instance

To create an action instance you need to pass the prepared action options to the Action instance constructor:

// create an action
var calloutAction = new CalloutAction(actionOptions);

Add the action to the callout

The last requirement is to add the created action to the callout’s actions collection:

// add the action to the callout
callout.addAction(calloutAction);

Additional action options

In addition to the required options for the action you can configure some additional but not required details.

tooltip

It defines the standard browser tooltip for the action which shows on the mouse over.

actionOptions.tooltip= 'Action 1 tooltip';

disabledTooltip

It’s the tooltip for the disabled state – it allows providing the information concerning the inaccessibility of your option.

actionOptions.disabledTooltip = 'Action 1 disabled tooltip';

isEnabledCallback

And here’s the way to rule the availability of your option:

actionOptions.isEnabledCallback = function (action) 
{
    // get the action text
    alert(action.getText());

    // set our action as enabled
    return true;
};
The only argument of this function is the action instance itself. The function must return a Boolean value indicating the availability of the action. If the action is disabled it will be grayed out:
If the isEnabledCallback function is not defined the action will be always available. The availability is being evaluated on each opening of the callout.

isVisibleCallback

This function helps to define the visibility of the action. It work exactly the same as the isEnabledCallback (see above) in any detail:

actionOptions.isVisibleCallback = function (action) 
{
    // get the action text
    alert(action.getText());

    // set our action as visible
    return true;
};

Actions with the dropdown menu

The last but not least option for the action configuration is the menuEntries property of the CalloutActionOptions object. It helps to define a special kind of the action – the one with the dropdown menu of options instead of a simple text. It allows combining several actions in the related and compact groups in order to save space, providing some logical structure for the actions list and adhering to the SharePoint Metro UI design principles.

If there are any items in the menuEntries, the action becomes a dropdown menu. In that case you can’t set the action’s onClickCallback handler because the action no more responsible for any real work and only expands its dropdown menu on click event.

menuEntries is just a standard JavaScript array containing CalloutActionMenuEntry instances. Each element corrensponds to a single menu item. Here’s the initialization example:

var menuEntries = new Array();
var menuEntry1 = new CalloutActionMenuEntry('Subaction 1', function (action, selectedEntryIndex)
{
    // Get the selected menu entry from the parent action
    var selectedEntry = action.getMenuEntries()[selectedEntryIndex];
    alert(selectedEntry.text);
});
menuEntries.push(menuEntry1);
var menuEntry2 = new CalloutActionMenuEntry('Subaction 2', function (action, selectedEntryIndex)
{
});
menuEntries.push(menuEntry2);
var menuActionOptions = new CalloutActionOptions();
menuActionOptions.text = 'Menu action';
menuActionOptions.menuEntries = menuEntries;
var menuAction = new CalloutAction(menuActionOptions);
callout.addAction(menuAction);

It’s the result:

If you click this action the dropdown will be opened:

The minimal parameters for each action menu entry are the text and the onClickCallback function. It’s not practical anyway but if you don’t provide them the whole action will not be shown and the error will be raised.

text

It’s the text of the menu entry.

onClickCallback

It’s the handler function for the menu entry click event. This function receives two arguments. First argument is the parent action of the clicked menu entry and the second one is the zero based index of the entry itself inside menuEntries array. The combination of these parameters allows getting the clicked entry:

var menuEntry1 = new CalloutActionMenuEntry('Subaction 1', function (action, selectedEntryIndex)
{
    // Get the selected menu entry from the parent action
    var selectedEntry = action.getMenuEntries()[selectedEntryIndex];
    alert(selectedEntry.text);
});

For the menu action the text option of the CalloutActionOptions is not required. If it doesn’t defined there will be ellipsis image drawn instead of the text:

The common design is to have a single menu at the end of the row but there are no restrictions on the menu position and quantity of menus inside the actions row. You can create multiple menus but I think it doesn’t adhere to the SharePoint Metro UI design.

Unresolved questions

There are some questions that need to be resolved still.

The CalloutActionMenuEntry class accepts four additional parameters: image url, image alt text, “sequence” and “description”. They all results in some HTML markup inside the generated menu item but it is unclear how they are used. For example, if you provide the image url correspondinf image will be rendered in menu item HTML but will be hidden.

There are some out-of-the-box callouts with additional customizations of action dropdown menu. For example, here are the separators:

It appears that the separators generation is implemented outside the “core” callouts UI framework. Can it be reused?



Previous: Custom Callouts in the SharePoint 2013 Metro UI, Part 1: Basics

Back to contents.

Next: Custom Callouts in the SharePoint 2013 Metro UI, Part 3: CalloutManager