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Data View Widget

The Data View Widget easily renders any dataset, which can be a JavaScript object, a JSON string, or an XML string. These are typically returned from database queries or REST API calls. The dataset could be as simple as a single set of properties, or a complicated nesting of arrays and objects. The Data View Widget enables a user to navigate through the dataset, and also to modify its contents.

The Data View Widget can optionally show a header if given a title option. As a user navigates into levels within a dataset, the Data View Widget will leave a breadcrumb trail near the header so the user can quickly jump back out to a higher level. The widget's control bar also has an egress button that navigates back to the previous level. The breadcrumb trail will also display a map marker icon when it detects that the currently viewed record is showing geographical location.

This document describes the Application Programming Interface (API) for the Data View Widget. There are two ways to invoke the Data View Widget: with a field drawn with fixed dimensions on a page, or as an event popup that is rendered full-screen.

Invoke as a ViziApps Field

To invoke the Data View Widget as a field drawn on a ViziApps page, first draw a field. An Image Field is convenient because you can see the full background, as in the following screenshot. If using an Image Field, set the image scaling to Scaled Fit.

In this example, the field is named editorField. The Data View Widget is invoked using the name of the ViziApps field, and would typically be created once, in the app's HTML Header, after the app has started. Note the jQuery convention to making reference to the ViziApps field by name: $('#editorField').

$( document ).on( "DOMContentLoaded", function() 
{
    $('#editorField').dataview();
});

Whenever a dataset is available at a later time, it can be passed to the Data View Widget as a value:

$('#editorField').dataview( "value", dataset );

Invoke as a Popup Event

It is not necessary to pre-define a field; the Data View Widget can be invoked as a full-screen popup. The dataset is passed as a parameter, and an optional title can be added.

$.viziapps.dataview({ value: dataset, title: "Important Information" });

Control Bar

When invoked as a popup, the Data View Widget will always incorporate a control bar at its bottom. When invoked as a ViziApps field, the control bar is included by default but may be removed as an option (see Options, below). The control bar includes:

  • An exit button, which closes the popup window
  • An egress button to navigate back up through a dataset
  • An edit button which enables editing of the dataset, but won't appear if options.editable is false
  • Array Up and Array Down buttons, which only appear when navigating through an array

Editing

When a user clicks the edit button in the control bar, the Data View Widget enters edit mode. The edit button will be highlighted, and all editable values will be marked with an edit (pencil) icon. Tapping on any editable field will popup an edit dialog which presents the user with the field name or key, the original field value, and a control to enter in a new value.

Options

Various options are available to change the appearance and behavior of the Data View Widget. Options may be included when the Data View Widget is created, as in the following:

$.viziapps.dataview({ value: dataset, editable: false });

Options may also be added any time after the Data View Widget has been created:

$('#editorField').dataview( "option", "editable", false );

The following options are available for the Data View Widget:

title string Title for the dataset, shown in a header
editable boolean Show the editing controls and allow the dataset to be edited
editMode boolean,string Enable or disable editing, or “toggle”
showControls boolean Show the built-in control bar with controls; ignored for popups
niceNames boolean Automatically convert dataset keys to text in a title style
arrayNames boolean, number, string Convert numeric array indices to a readable text property within each row's objects
nameMap string map A map object of key names with formal names to show the user
style list CSS style overrides to the default theme
icons list icon definition overrides to the default icons
strings list All text within the widget, including buttons
fadeDuration number Number of milliseconds for visual transitions. Set to zero to eliminate animations.

Event Callbacks

An app can monitor event callbacks to catch changes in the dataset.

change dataviewchange Whenever a user saves any change to the dataset
control dataviewcontrol Whenever a control bar button is pressed
close dataviewclose When the Data View Widget is closed

Callbacks may be defined when the Data View Widget is created:

$('#editorField').dataview( { 
    change: function( event, ui )
    {
        console.log( 'change: ' + ui.original + ' -> ' + ui.value );
    },
    close: function( event, ui )
    {
        console.log( 'close: ' + ui.changes + ' -> ' + JSON.stringify( ui.value, null, '  ' ) );
    }
});

Callbacks may also be defined as a jQuery event after the Data View Widget is created:

$('#editorField').bind( 'dataviewchange', function( event, ui )
{
    console.log( 'change: ' + ui.original + ' -> ' + ui.value );
});
$('#editorField').bind( 'dataviewclose', function( event, ui )
{
    console.log( 'close: ' + ui.changes + ' -> ' + JSON.stringify( ui.value, null, '  ' ) );
});

Some callbacks allow the handler to return false, which prevents the widget from processing its default action. All control events allow the app to hook the control buttons in this way.

Methods

value Get the current dataset being edited
value record Pass a new dataset to edit, replacing any current dataset
egress Have the Data View Widget navigate back one level
arrayUp Move to previous record in a dataset array.
arrayDn Move to next record in a dataset array.
close Close the Data View Widget, which generates a save/discard dialog

Methods may be called using the named field:

var currentRecord = $('#editorField').dataview( "value" );
$('#editorField').dataview( "egress" );

When invoked as a popup, you can store the widget's ID in the create callback:

var widgetID;
$.viziapps.dataview({
    value: dataSet,
    create: function( event, ui ) { widgetID = ui.id; }
});
function getWidgetValue() {
    return $( '#' + widgetID ).dataview( "value" );
}