Running Canvas Screens

On the Canvas toolbar, click Run or debug selected screen (Run selected screen) to open a Canvas Viewer preview window for the currently selected screen, containing all saved user features. Screens will be automatically saved prior to previewing.

The Canvas Viewer window provides the screen developer a view of current work as it will appear to users. Use the preview feature to preview your screens in run mode, so you can test out usability, workflow, load time and help further refine your design. This will help you to understand the implications of editing decisions while the screen is still in progress. The Canvas Viewer window floats in front of the current application window by default.

Canvas Viewer Toolbar

The Canvas Viewer dialog box contains a navigational toolbar which allows you to refresh a screen, show the default chart, start the historical playback bar, and choose a different Facility tag or SiteService / Facility combination for the previewed screen. The toolbar also displays the Load time for the screen. The toolbar items are described below.

Canvas Viewer toolbar

Canvas Viewer — Navigation Toolbar options

Item

Tooltip

Description

Refresh button

Refresh screen

Click to restart the screen, for example, if you have script that runs at the start of a screen you can click refresh to initialize the screen.

Default chart button

Show default chart

Not supported by TWC Click to open a previously saved default chart. Choose the location where the default chart is saved in the Open dialog box, either in an APPS or BSS folder or a local or network file-system folder. See Default Chart for more information about the default chart feature.

Show historical playback

Not supported by TWC Click to open the historical playback bar. See Using Historical Playback for more information about the historical playback bar feature.

Facility tag or

SiteService / Facility radio buttons

Two selection modes are available to determine how the CygNet connection will be configured for the screen. This split configuration allows for the setting of these properties for the screen, or the manual configuration of the SiteService and the facility, while dynamically changing the other. Options include:

Facility tag — The Facility tag selector consists of a source chooser. Facility tag is the default option.
SiteService / Facility — The SiteService / Facility selector consists of separate SiteService and facility choosers.

Click the desired mode and the selectors will change.

Facility tag > Facility Tag selector

If your screen is configured to pick up data from a different facility tag, you can change the full facility tag identifier used. Click Open dialog box to select a different facility tag identifier using the Select Facility Tag dialog box.

SiteService / Facility > Service and Facility selectors

If your screen is configured to pick up data from a different service, you can change the service used. Click Open dialog box to select a different service using the Select Service dialog box.

If your screen is configured to pick up data from a different facility, you can change the facility used. Click Open dialog box to select a different facility using the Select Facility dialog box.

Load time: nn.nnnn ms

Load time tells you how long Canvas took to load the previewed screen in milliseconds (ms).

Click Load time: to access a small popup, which provides a more granular understanding of where time is being spent as the previewed screen is loaded. Load time is a summation of the time it took to process all the elements of the screen: initialize screen, parse xml, load controls, apply styles, run script, etc.

The screen load times are also available via the log file if Debug logging is enabled.

Canvas Viewer toolbar — load time popup

Canvas Viewer toolbar — Load time popup

The following list describes all metrics available:

Add controls — The time it takes to add controls to the screen.
Apply control styles — The time it takes to apply styles to all controls.
Average load time per control — The average time it takes to load each control (total load / number of controls)
Connect control delegates — The time it takes to connect controls to any delegates.
Controls start — The time it takes to start all controls.
Create controls — The time it takes to create all controls.
Deserialize control properties — The time it takes to load the saved properties into each control.
Jump start cache — The time it takes to jump start the cache.
Load controls — The time it takes to load the controls on the screen.
Parse xml — The time it takes to parse the xml for the screen.
Set proportional ratios — The time it takes to set the proportional resize values for the screen and controls.
Screen initialize — The time it takes to initialize the screen.
Screen start — The time it takes to start the screen.
Script compile — The time it takes to compile the script on the screen.
Script initialize — The time it takes to initialize the script on the screen.
Script start — The time it takes to start the script on the screen.

Note: This toolbar does not appear in a screen opened in Canvas.View.

Run Modes

In Canvas v9.4 and later a new run mode method was introduced to improve screen performance and reduce load time. This enhanced run mode is the default method when you hit F5. The new run mode also allows you to dynamically add controls via script.

Note: The new run mode implemented in Canvas v9.4 and later does not support panning and zooming. Thus, Canvas has retained the old method of running screens for backwards compatibility. If you need to pan and zoom on a specific screen (configured via the IsPanZoomEnabled property on a screen), you will not be able to take advantage of the performance improvements the new run mode supports. The legacy run mode is accessible from the Run icon on the Canvas toolbar: Run > Run current screen (Legacy).