Chapter 17 UI Assistant Overview

This chapter introduces you to VA Assist Pro’s UI Assistant. In this chapter you will

•	become familiar with the UI Assistant environment

•	quickly boost your VA Smalltalk productivity using the UI Assistant’s special features

Starting the UI Assistant

You will notice that the installation procedure has added a new menu item, VA Assist Pro, to the Transcript’s Tools menu.

To start the UI Assistant:

•

Start the VAST Composition Editor in the normal manner. If embedded mode is turned on (the default), the UI Assistant will replace the standard Composition Editor toolbar with its own. If embedded mode is turned off, the UI Assistant window will initially appear as a small floating window in the upper right corner of your screen (you can customize where the UI Assistant should initially appear via the Setup page). The UI Assistant window will interact with the active Composition Editor.

The UI Assistant screen appears, as shown on the next page:

Standard Page	Replicates the Composition Editor’s standard toolbar. It has been augmented with standard Cut, Copy and Paste functions as well as Undo and Redo.
Tools Page	Includes common commands like Test, New, Open, Save, Cut, Copy, Paste, Undo, Redo, Select All, Inspect, etc.
Settings Page	Contains commands for modifying the characteristics of the selected parts such as Color, Font, Settings, Morphing, etc.
Layout Page	Includes almost two dozen common attachment styles that can be applied to one or more widgets with a single mouse click.
Size & Position Page	Includes commands for setting sizes and positions of widgets and for aligning them relative to one another.
Links Page	Gives you a dozen options for displaying and filtering displays of links.
Parts Page	Gives you quick access to all of the parts found on the Composition Editor’s palette.
Setup Page	Contains commands for customizing VA Assist Pro itself.
Help Button	Provides help for the UI Assistant.
About Button	Displays the VA Assist Pro About Dialog.
New Assist Button	Opens a new copy of the UI Assistant.

Enabling and Disabling VA Assist Pro

If you would like to disable VA Assist Pro for any reason (so that it does not appear), execute the following in a workspace:

VisualAgeAssist disable

To re-enable VA Assist Pro, execute:

VisualAgeAssist enable

You may also use the Enable/Disable options off of the VA Assist Pro sub menu of the Transcript’s Tools menu.

Using the UI Assistant

In order to quickly familiarize yourself with some of the UI Assistant’s most useful features, we will go through a number of simple examples of how the UI Assistant can save you a great deal of time. For each example, we will specify a task, describe how you would accomplish the task using the Composition Editor and then show you how to do the same task quicker and easier with the UI Assistant.

Setting Attachments

One of the hardest and most time consuming procedures in the Composition Editor is the setting of attachments. Attachments specify how a widget will re-size itself when its parent form or window re-sizes. It is quite common, for example, to want to lock a group of buttons to the lower right corner of the screen or to lock the top and bottom of a listbox to the top and bottom of the screen so that it grows to fill the extra space as the window is made larger.

As an example, we will explore the steps necessary to lock a group of buttons (e.g., OK, Cancel and Apply) to the lower right corner of the window:

Setting Attachments without the UI Assistant

1.	Select a button.

2.	Open the settings view on the button.

3.	Switch to the Layout Page.

4.	Set the Top Edge to “Parent Bottom”.

5.	Click on “Left”.

6.	Set the Left Edge to “Parent Right”.

7.	Click on OK.

8.	Repeat for each button. For many attachment styles, you might need to set the bottom and right sides of the widget as well.

For a group of five widgets, it would take at least 35 mouse clicks to complete this task. For a window composed of several dozen widgets, it could take several hundred mouse clicks to set all of the attachments correctly.

Setting Attachments with the UI Assistant

1.	Shift-select each button

2.	Switch to the the UI Assistant Layout page

3.	Click the Lock to Bottom-Right Corner button (shown below)

For a group of five widgets, it would take no more than seven mouse clicks - a clear five to one savings of effort. The more widgets on the page, the more dramatic the time-savings.

Setting Styles

Another common operation when laying out a window is the setting of styles for the various widgets. Using the Composition Editor, all style settings are accomplished via the Settings View for the widget. For setting the styles of one widget, this isn’t too bad. If you need to change the style for a number of widgets, this can be very time consuming and repetitive.

A common example is the need to left or right align labels on the screen. By default, the Composition Editor creates all new labels center aligned - which is almost never the appropriate choice. We will explore the steps required to right align a large number of labels in a single window:

Setting Label Alignment without the UI Assistant

1.	Select a label.

2.	Open the settings view on the label.

3.	Switch to the second page.

4.	Change the alignment to Left or Right

5.	Click on OK.

6.	Repeat for each label.

For a screen full of dozens of labels and text fields, the above process would take many dozens of mouse clicks.

Setting Label Alignment with the UI Assistant

1.	Select one label.

2.	Click the Select All In Same Class button (this selects all the other labels for you).

3.

4.	Switch to the UI Assistant Settings page.

5.	Select Left or Right from the context sensitive style combobox labeled Alignment (shown below).

For a window that contained just twenty-five labels, it would take well over a hundred mouse clicks without the UI Assistant. With the UI Assistant, it takes only four (or three if you happened to have the UI Assistant already open to the Settings page).

Setting Colors

As you can see, the UI Assistant makes it easy to change styles for a collection of widgets all at once. Changing styles need not be limited to homogeneous collections of widgets either. Another common problem is the need to change the background color for a number of widgets (or all of the widgets on the screen). The UI Assistant’s style settings tools can make this easier as well:

Setting Background Color without the UI Assistant

1.	Click on the Sticky checkbox to enable sticky mode

2.	Open the Color selection window via the “Options | Color...” menu.

3.	Choose a color. The cursor now changes into a spray can.

4.	Click on a widget.

5.	Select Foreground or Background to set the desired color.

6.	Repeat the previous two steps for each widget.

7.	Click on the Selection Tool button to clear sticky mode.

For a large number of buttons, this can be a time consuming and repetitive operation.

Setting Background Color with the UI Assistant

1.	Shift select each widget or click on the Select All button to select all of the widgets.

2.	Switch to the UI Assistant Settings page

3.	Select a color from the context sensitive style combobox labeled Background Color (shown below).

As you can see, the style comboboxes can be used with a heterogeneous collection of widgets. As you select a widget or collection of widgets, the UI Assistant will display the two most common attributes that the selected widgets all have in common. You can switch either combobox to display a different attribute by Right-clicking on it and selecting a new attribute type. The UI Assistant will automatically remember any attribute changes you make for the selected widget type.

The UI Assistant provides a number of ways to change widget colors in addition to the technique outlined above. In addition to the style comboboxes, you can also click the Color button on the UI Assistant Settings page to launch the standard Color selection window.

Right-clicking on the Color button will give you a popup list of common colors and allow you to bypass the Color selection window all together.

Setting Fonts

The UI Assistant makes setting fonts easier as well. With the Composition Editor, you are forced to select a font and then “paint” it onto each widget that should have that font. For a window full of widgets, this can be very time consuming.

The UI Assistant augments this process by allowing you to apply font changes to multiple widgets simultaneously. For example:

Setting Fonts the UI Assistant

1.	Shift select each widget or click on the Select All button to select all of the widgets.

2.	Switch to the UI Assistant Settings page.

3.	Click the Font button (shown below) to open the Font selection dialog.

4.	Select a font and click OK. The font selection will be applied to all of the selected widgets.

Note that shift-clicking on the font button opens the Font selection dialog in the same manner as the Composition Editor “Options | Fonts...” command. Selecting a font will then allow you to paint the selected font onto one or more widgets.

Morphing

As a window design matures, additional space and functionality constraints may make it necessary to replace one widget type with another. If a widget participates in a number of connections and has lots of custom attribute settings, switching to a new widget type (either a similar type of widget or a subclass of the existing widget) can be a very painful and error prone task. You would need to delete the existing widget, create a new one in its place, and then re-create every connection and attribute setting. Not fun!

The UI Assistant provides a morphing function that makes it easy to swap one widget type for another. In general, any primitive widget (e.g., button, label, list, etc.) can be morphed into any other primitive type. Likewise, any composite widget (e.g., form, groupbox, etc.) can be morphed into any other composite type. Clicking on the Morph button (shown below) on the Settings page pops up a list of widget types similar to the source widget. Selecting a new widget type will then morph the selected widget (or widgets) into the new type.

Each connection and attribute is semantically validated during the morphing process to ensure that the parts remain valid. Connections that become invalid because the event, action or attribute does not exist in the target widget type are automatically removed. Attributes that the source and target widget types have in common are automatically migrated over. Attributes that no longer exist are dropped while new attributes are appropriately defaulted. The entire morphing process is logged to the Transcript so that you can note any attributes or connections that are lost. If you are unhappy with the morph, you can always undo the operation and be right back where you started.

Link Filtering

Visual programming is a very powerful technique for rapidly building user interfaces. It is also a technique for rapidly building interfaces that no one except the original developer can understand. The term “spaghetti code“ takes on new significance when staring at a screen covered by dozens if not hundreds of crisscrossing green and blue lines. The UI Assistant’s Links page dramatically improves this situation by allowing you to peel away layers of connections and focus in on just the ones you are interested in.

The UI Assistant gives you tools that allow you to look at any combination of event to action or attribute connections that you want. For an individual part, you can look at just the links that are associated with that part. As you click on different parts, the displayed connections are hidden and shown dynamically. You can further filter the displayed links by concentrating on just the event connections (incoming, outgoing or both), or just the attribute connections (using the buttons shown below).

You can even filter down to specific kinds of events (e.g., just clicked events or object attribute connections) using the link filter combobox shown below. After selecting the Event, Action, or Attribute radiobutton, you can select an event, action or attribute filter that will be applied to all toolbar button commands. The filter list is derived dynamically from the parts present in the Composition Editor. For example, you could select a clicked event filter. Clicking the Show All Connections button will then show all the clicked event links for all the parts. If the Dynamic Links setting is enabled, the Filter combobox can be used to quickly hide/show different combinations of connections. The last toolbar selection will be automatically applied as the filter is updated.