Warning: main(/www/www/htdocs/style/globals.php) [function.main]: failed to open stream: No such file or directory in /www/www/docs/6.4.1/photon/prog_guide/widgets.html on line 1

Warning: main() [function.include]: Failed opening '/www/www/htdocs/style/globals.php' for inclusion (include_path='.:/www/www/common:/www/www/php/lib/php') in /www/www/docs/6.4.1/photon/prog_guide/widgets.html on line 1

Warning: main(/www/www/htdocs/style/header.php) [function.main]: failed to open stream: No such file or directory in /www/www/docs/6.4.1/photon/prog_guide/widgets.html on line 8

Warning: main() [function.include]: Failed opening '/www/www/htdocs/style/header.php' for inclusion (include_path='.:/www/www/common:/www/www/php/lib/php') in /www/www/docs/6.4.1/photon/prog_guide/widgets.html on line 8

Creating Widgets in PhAB

Once you've created or opened an application, you'll probably want to add, delete, and modify widgets. This chapter describes how to work with widgets.

It includes:

Note: For information on using specific widget classes, see:

Since widgets inherit a lot of behavior from their parent classes, you should make yourself familiar with the fundamental classes: PtWidget, PtBasic, PtContainer, and so on.


Types of widgets

There are two major types of widgets:

Container-class widgets can contain other widgets—including other containers. Widgets placed inside a container are known as child widgets; the hierarchy resulting from this nesting is called the widget family. Container widgets can look after sizing and positioning their children, as described in the Geometry Management chapter.

When working with container-class widgets in PhAB, remember the following:

Instance names

If your program has to interact with a widget, that widget must have a unique instance name. Using this name, PhAB generates a global variable and a manifest that let you easily access the widget from within your code.

To view or edit a widget's instance name, use the Widget Instance Name field at the top of the Resources or Callbacks control panel:


Instance name


Editing a widget's instance name.


Note:
  • A widget's instance name is used to make several C variables, so it can include only letters, digits and underscores. PhAB doesn't let you use any other characters. An instance name can be no longer than 64 characters.
  • You should develop a naming convention for all the widgets in your application — it will make large applications more manageable.

You can optionally include the instance name in the widget's memory. See Other Generate options in the Working with Applications chapter.

Default instance name

When you create a widget, PhAB automatically gives it a default instance name. Typically, this default name is the widget's class name. For example, if you create a PtButton-class widget, the Resources and Callbacks control panels display PtButton as the instance name.

If a widget simply serves as a label or window decoration, it doesn't have to be accessed from within your application code. So you should tell PhAB to ignore the widget's instance name during code generation. To do this:

When to assign a unique name

You should give a widget a unique name if:


Note: To keep the number of global variables to a minimum, don't give a widget a unique name unless you really need to access the widget from within your application. If you've given a widget a name and later decide you don't need the name, just change it back to the widget's class name or blank it out.

Instance names and translations

As described in the chapter on International Language Support, you'll need an instance name for every text string in your application's user interface. These instance names aren't needed in your code.

To indicate that an instance name isn't required for code generation, start the name with the @ character. PhAB recognizes such a name when generating the text language database, but skips over it when generating code.

If you don't want to create a unique instance name for a string that's to be translated, specify a single @ character for the instance name; PhAB appends an internal sequence number to the end.

If you don't want to create unique instance names, but you want to organize the text for translation (say by modules), you can give the strings the same instance name, and PhAB will append a sequence number to it. For example, if you assign an instance name of @label to several strings, PhAB generates @label, @label0, @label1, ... as instance names.

Duplicate names

PhAB resets the instance name of a widget back to the widget class name if it detects a duplicate name when you:

Creating a widget

To create a widget:

  1. Click on widget-palette icon for the type of widget you want to create (see the Widgets at a Glance appendix to identify the widget-palette icons).
  2. Move the pointer to where you want to create the widget. The pointer changes to show you what to do next:

Note: Widgets snap to the grid if it's enabled. See Grid preferences in the chapter on PhAB's environment.

To improve your application's performance, avoid overlapping widgets that are frequently updated.


You can also create a widget by dragging its icon from the widget palette to the Module Tree control panel. Where you drop the icon determines the widget's place in the family hierarchy.

Creating several widgets

Once you've created a widget, you're returned to select mode. To stay in create mode so you can create several widgets of the same type:

  1. Press and hold down Ctrl.
  2. Create as many widgets as you want.
  3. Release Ctrl.

Canceling create mode

To cancel create mode without creating a widget:

Selecting widgets

In this section we look at:

When PhAB is in select mode, the pointer appears as an arrow. To put PhAB into select mode:

A single widget

To select a single widget, you can:

These methods are described below.

Point-and-click method

To select a single widget using point and click:

  1. Make sure you're in select mode.
  2. Click on the widget, using the left mouse button. Resize handles appear around the widget.

To select the parent of a widget, hold down Shift-Alt and click on the widget. This is a handy way to select a PtDivider or PtToolbar.


Note: You must press Shift and then Alt for this method to work.

Control-panel methods

The Next and Previous buttons in the Resources and Callbacks control panels let you select any widget in the current module.

To select the: Click on: Or press:
Previous widget in the current module

Previous arrow

F9
Next widget in the current module

Next arrow

F10

The Module Tree control panel displays a tree of all the widgets in the module. Using this tree, you can:

To select a widget from the tree, click on the widget's name.

Multiple widgets

To select multiple widgets, you can:


Note: When you select two or more widgets, the Resources control panel displays only the resources that those widgets have in common. Editing any of these resources affects all the selected widgets.

PhAB uses two colors to show selected items if the Show Selection option is selected in the View menu. The colors can be customized in the Preferences dialog.


Multiple Selection


Multiple selected widgets.

In the example above, the toggle widget is not selected, it just happens to be in the same area as the selected widgets. The widget highlighted by red is the first widget in the selection. The widgets highlighted by blue are the rest of the widgets in the selection. If you use an align or match command, the first selected widget is the source widget.

Using a bounding box

A bounding box lets you select several widgets all at once:

  1. Position the pointer above and to the left of the widgets you want to select.
  2. If the widgets belong to a container such as PtBkgd, make sure the pointer is within the container, then hold down the Alt key.
  3. Hold down the left mouse button, then drag the pointer down to the right. You'll see an outline “grow” on the screen.
  4. When all the widgets are within the outline, release the mouse button. You'll see resize handles appear around the area defined by the selected widgets.

Using Shift and click”

To add or remove a widget from the current list of selected widgets, hold down Shift and click on the widget. This is also known as the extended selection method.

If the widget isn't already selected, it's added to the list. If the widget is already selected, it's removed from the list.


Note: The above methods for selecting multiple widgets work only for widgets at the same hierarchical level. For example, let's say you've just selected two buttons inside a window. You can't extend that selection to include a button that's inside a pane.

Using the control panels

To select multiple widgets, using the Resources or Callbacks control panel's Next and Previous buttons:

  1. Hold down Shift.
  2. Click on the Next button.

    Every time you click, PhAB adds the next widget in the current module to your selection.

To remove the last widget from the current list of selected widgets:

  1. Hold down Shift.
  2. Click on the Previous button.

    Every time you click, PhAB removes another widget.

Widgets within a group

To select a widget inside a group, you can use the next and previous buttons in the Resources or Callbacks control panel, or use the Module Tree control panel.

Using the Module Tree panel

To select a single widget within a group, using the Module Tree control panel:

  1. Switch to the Module Tree control panel.
  2. Find the group in the tree and click on the widget's name.
  3. Shift-click to select additional widgets, if you want.
  4. To edit the widget, switch to the Resources or Callbacks control panel.

Using the Next and Previous buttons

To select one or more widgets within a group, using the Next and Previous buttons:

  1. Click on any widget within the group to select the entire group.
  2. Click on the Resources or Callbacks control panel's Next button (or press F10) until the widget you want is selected.
  3. To select additional widgets, press Shift, then click again on the Next button.
  4. You can now edit the widgets' resources or callbacks.

Hidden widgets

If you can't find a widget (it may be hidden behind another widget or is outside the boundaries of its container), do the following:

  1. Use the Next and Previous buttons in the Resources or Callbacks control panel.
  2. Select the widget from the Module Tree control panel.
  3. Use the Search dialog. Select Edit-->Find to open this dialog.
  4. If the widget seems to be outside the current boundaries of its container, bring it back into view by using the X and Y fields in PhAB's toolbars.

For more information on the toolbars and control panels, see the chapter on PhAB's environment.

Aligning widgets

You can align several widgets to another widget or to their parent container.

For simple alignments, select the Align icon from PhAB's toolbar:

Alignment Icon

and then choose the alignment from the pop-up menu.

For more complicated alignment options, bring up the Align Widgets dialog by:

To another widget

When you use this method to align widgets, the widgets are aligned to the first widget you select, which is highlighted differently from the other widgets in the selection if the Show Selection option is set in the View menu. To align to another widget:

  1. Select the first widget.
  2. Using the Shift and click” selection method, select the remaining widgets. (This method is described in Selecting widgets.)
  3. For simple alignments, select the Align icon from PhAB's toolbar and make a choice from the menu.
  4. For more complicated alignment options, bring up the Align Widgets dialog. Choose one or more alignment options, then click on the Align button. Don't click on an Align to Container button.

To a parent container

To align widgets to their parent container:

  1. Select one or more widgets in any order.
  2. Bring up the Align Widgets dialog, choose your alignment options, then click on the appropriate Align to Container button.

    Note: If you choose both vertical and horizontal options, be sure to click on both Align to Container buttons.

  3. Click on the Align button.

When aligning widgets to a container you may want the widgets to retain their relative positions to each other. To do this:

  1. Group the widgets together (see the section Aligning widgets using groups in the Geometry Management chapter).
  2. Align the widgets.
  3. Optionally, break the group apart.

Distributing widgets

You can quickly and easily distribute widgets horizontally or vertically, to evenly space them out on the GUI. To do this:

  1. Select the widgets you want to distribute.
  2. From the Widget menu, select Distribute-->Horizontally or Distribute-->Vertically.

In the following example, several buttons have been distributed horizontally and aligned to the top edge:


Distributed widgets


Distributed widgets.

Common User Access (CUA) and handling focus

Common User Access (CUA) is a standard that defines how a user can change the keyboard focus. A widget is focusable if it can be given focus by pressing CUA keys or by calling a focus function.

Changing focus with the keyboard

The following keys move focus only to focusable widgets:

To go to the: Press:
Next widget Tab
Previous widget Shift-Tab
First widget in the next container Ctrl-Tab
Last widget in the previous container Ctrl-Shift-Tab

For information on specifying the order in which the widgets are traversed, see the section “Ordering widgets” in this chapter.

Controlling focus

Use the following Pt_ARG_FLAGS flags to control focus for a widget:

Pt_GETS_FOCUS
Make the widget focusable.
Pt_FOCUS_RENDER
Make the widget give a visual indication that it has focus.

In addition, use the following Pt_ARG_CONTAINER_FLAGS flags to control focus for a container:

Pt_BLOCK_CUA_FOCUS
Prevent the CUA keys from being used to enter the container. However, if the user clicks inside the container, or a focus function gives it focus, the CUA keys can then be used.
Pt_ENABLE_CUA
Give the parent widget the chance to control whether or not a child container handles the CUA keys:
Pt_ENABLE_CUA_ARROWS
The same as Pt_ENABLE_CUA, but it applies only to the arrow keys.

Focus callbacks

All descendants of the PtBasic widget have the following callback resources:


Note: PtMultiText and PtText have special versions of these callbacks.

For more information, see the Widget Reference.

Focus-handling functions

The functions listed below deal with focus. They're described in the Photon Library Reference.

These functions don't actually change which widget has focus; they tell you where focus can go:

PtFindFocusChild()
Find the closest focusable child widget
PtFindFocusNextFrom()
Find the next widget that can get focus
PtFindFocusPrevFrom()
Find the previous widget that can get focus

You can use these routines to determine which widget has focus:

PtContainerFindFocus()
Find the currently focused widget in the same family hierarchy as a widget
PtIsFocused()
Determine to what degree a widget is focused

You can use these routines to give focus to a widget:

PtContainerFocusNext()
Give focus to the next Pt_GETS_FOCUS widget
PtContainerFocusPrev()
Give focus to the previous Pt_GETS_FOCUS widget
PtContainerGiveFocus() or PtGiveFocus()
Give focus to a widget — these routines are identical.
PtContainerNullFocus()
Nullify the focus of a widget
PtGlobalFocusNext()
Give focus to next widget
PtGlobalFocusNextContainer()
Give focus to another container's widget
PtGlobalFocusNextFrom()
Give focus to the next widget behind the specified widget
PtGlobalFocusPrev()
Give focus to the previous widget
PtGlobalFocusPrevContainer()
Give focus to a widget in the previous container
PtGlobalFocusPrevFrom()
Give focus to widget previous to the specified widget

Ordering widgets

In PhAB, each widget exists in front of or behind other widgets. This is known as the widget order, and you can see it when you overlap several widgets. The order of the widgets dictates how you can use the CUA keys to move between widgets.


Note: If you're not using PhAB, the widget order is the order in which the widgets are created. To change the order, see Ordering widgets in the Managing Widgets in Application Code chapter.

To view the widget order, do one of the following:

The easiest way to reorder the widgets is to use the Module Tree control panel — just drag the widgets around until they're in the order you want.

You can also use the Shift-select method to reorder the widgets:

  1. Using the extended (Shift and click”) selection method, select the widgets in the order you want. (This selection method is described in “Selecting widgets.”)
  2. Do one of the following:

You can also select one or more widgets and then use the Raise and Lower icons to change the widget order:

Raise/Lower icons

Dragging widgets

Dragging a widget is the easiest way to move a widget in most situations since it's quick and fairly accurate:

  1. Select the widgets.
  2. Point to one of the selected widgets, press down the mouse button, then drag the widgets to the new position.

    If you want to drag the widgets horizontally, vertically, or diagonally, hold down the Alt while dragging.


    Note: To drag a container horizontally, vertically, or diagonally, press Alt after pressing the mouse button. (Pressing Alt before the mouse button selects widgets within the container.)

  3. Release the mouse button. Widgets snap to the grid if it's enabled — see Grid preferences in the chapter on PhAB's environment.

To cancel a drag operation, press Esc before releasing the mouse button.

To move the parent container of a widget, hold down Shift-Alt and drag the child.

Another way to drag a widget is to hold down Shift while selecting and draging one of the widget's resize handles. This method may help when you're moving smaller widgets that are harder to select.

Widgets may “disappear” if you move them beyond the boundaries of their container. If this happens, use the Previous and Next buttons in the Resources or Callbacks control panel to select the widgets, then use the X and Y fields in PhAB's toolbar to bring the widgets back into view.

If you find that you're unintentionally dragging widgets when you're just trying to select them, consider:

Dragging preferences

There are several preferences that you can set for dragging (see the Customizing your PhAB environment section in the chapter on PhAB's environment):

Setting a widget's x and y coordinates

To place one or more widgets at specific coordinates:

  1. Select the widgets.
  2. Type the coordinates in the x and y fields in PhAB's toolbars, then press Enter. For more information, see the chapter on PhAB's environment.

Transferring widgets between containers

To move one or more widgets directly from one container or module to another:

  1. Select the widgets.
  2. Do one of the following:
  3. Move the pointer into the other container and click the mouse button.

Resizing widgets and modules

When you select a widget or module, you'll see its height and width—including any borders and margins—displayed in the toolbar's H and W fields. (These values are maintained by the Pt_ARG_DIM resource; see the description of PtWidget in the Widget Reference.)

To resize a selected widget, do one of the following:


Note: If a module is in Test mode, you can't resize it or its widgets.

If you have trouble seeing a widget's resize handles because of the background color you've chosen, you can change the resize-handle color. For more info, see Customizing your PhAB environment in the PhAB Environment chapter.


Clipboard

PhAB's clipboard lets you cut, copy, and paste widgets and modules between PhAB instances. You can't use this clipboard with other applications. To use the clipboard, open two PhAB instances, copy or cut something into clipboard in one instance, and then paste it into the other instance.

You'll find the clipboard helpful for these reasons:

Cutting and copying

A cut operation removes the currently selected widgets from their module and places them in the clipboard. A copy operation copies the currently selected widgets to the clipboard without removing them from their module.


Note: Whenever you cut or copy, PhAB deletes any widgets already in the clipboard.

To cut or copy one or more widgets:

  1. Select the widgets.
  2. To cut, do one of the following:
  3. To copy, do one of the following:

Note:
  • If you want to move a widget to another container but retain its callbacks, you need to set the Save/Restore Callbacks option on the General tab of the Preferences dialog. See Transferring widgets between containers in this chapter.
  • The Edit menu also contains a Delete command. This command permanently removes widgets without copying them to the clipboard.

Pasting

A paste operation copies widgets from the clipboard into a module.

To paste the contents of the clipboard:

  1. Make sure you're in Select mode.
  2. Do one of the following:
  3. Point to where you'd like the clipboard objects to appear, then click the mouse.

Note:
  • Instance names are normally maintained when you paste. But if PhAB detects a duplicate name, it ensures that the instance name is unique.
  • Because the clipboard state is saved between PhAB applications, you can cut widgets from one PhAB application and paste them into another.

Duplicating widgets and containers

Here's a quick and easy way to duplicate a widget or container (it's much simpler than using the clipboard):

  1. Press and hold down Ctrl.
  2. Point to the widget or container, hold down the left mouse button, then drag the pointer to where you'd like the new widget to appear.
  3. Release Ctrl and the mouse button.

If you want to duplicate many widgets at once:

  1. Select the widgets you want to duplicate.
  2. Press and hold down Ctrl.
  3. Point to one of the widgets in the selection and drag to a new position.
  4. Release Ctrl and the mouse button.


Note: If you duplicate a container, all its children are duplicated as well.

Duplicating is achieved using a copy to clipboard operation and paste from clipboard, that are done internally. Therefore the rules for clipboard operations about instance names and callback are also valid for duplicating widgets.


Note:
  • You can duplicate only one container or widget at a time. If you duplicate a container, all its children are duplicated as well.
  • The instance names of the new widgets are reset to be the widget class name.
  • Callbacks aren't duplicated.

Deleting widgets or modules

To permanently remove one or more selected widgets, or to delete a module:

  1. Select the widgets or module.
  2. Choose Delete from the Edit menu or press Delete.

If you want put the widgets or module somewhere else, you should cut them, not delete them. For more information, see the section on the clipboard in this chapter.

Matching widget resources and callbacks

You can copy the resources or callbacks from one widget to one or more other widgets by using the Matching feature. This features lets you quickly and easily create several widgets with similar appearances and behavior.

To use the matching feature:

  1. Select the widget that is the source for the resources or callbacks.
  2. Select one or more destination widgets.

    Note: If you enable the Show Selection option in the View menu, the widget selected first highlighted with a different color than other selected widgets.

  3. Select a match command from the Widget menu:


Match resources and callbacks dialog


Match resources and callbacks dialog.

Importing graphic files

PhAB lets you import several kinds of graphic files into your application. For more information, see Importing files in the Working with Applications chapter.


Note: PhAB doesn't export graphic files directly. That's because any imported file is saved with the module in a PhAB-specific format.

The Pixmap editor (described in the Editing Resources and Callbacks in PhAB chapter) also lets you import graphics: select the widget you want to add the image to, edit its image, and choose the pixmap editor's Import button.

Changing a widget's class

You can change the class of a widget by selecting it and then choosing Change Class from the Widget menu. Choose the new class from the pop-up list, and then click the Change class button.

The resources and callbacks that are compatible with the new widget class are kept, along with their values. For example, if you decide that a PtMultitext better suits your needs than a PtButton, you can select the button, open the Change class dialog by right-clicking on the widget, or right-clicking in the Module tree or by choosing Change Class from the Widget menu. The widget's position, size, Pt_ARG_TEXT_STRING, and all the other resources common to the old and new classes are kept.


Note: When you change a widget's class, some resources and callbacks might be deleted. Before proceeding, a dialog displays the number of resources and callbacks that will be removed. You have a chance to cancel the operation.

A container that has children (such as a PtPanel with some widgets inside it) can be converted this way, but the list of possible new classes you can choose from is restricted to compatible container classes. For instance a PtPane with a button inside can be changed into a PtBkgd, but not into a PtList or PtTree. An empty PtTree or any other empty container can be changed into anything, including into non-container widgets. A PtTree that has a child (a PtDivider) can be changed into a container widget.

Templates

A template is a customized widget, group or hierarchy of widgets that you want to use as the basis for other widgets. Templates are useful when you want to create many widgets that look and behave alike. PhAB automatically loads your templates, so you can easily create instances of your widgets in any application.

You can build and save your own collection of template widgets. Templates can be customized buttons, labels, sliders, backgrounds, standard dialogs and windows. You can include callbacks in templates.

Customized templates are not any different from the standard templates in the Widgets palette. In fact, when you create a template, you save it as a personal template (visible only to you) or as a global PhAB template (visible in all PhAB instances).


Note: For an example of creating a template, see Editing Resources in the Tutorials chapter.

This section includes:

Creating templates

To create a template:

  1. Create and edit the widget or widgets as required.
  2. With the widget(s) selected, choose Define Template from the Widget menu or from the menu that appears when you right-click on the Module Tree control panel or on the module.
  3. The Define template dialog appears.

    Save as template dialog


    The dialog for creating new templates.

  4. Select the folder in which to place the new template. To replace an existing template, select the template instead of a folder.

    To create a new folder, click on Add Folder. The Setup folders dialog appears:

    Setup folders dialog

    Enter a folder name and select its type: User folder or PhAB folder. A User folder is visible only to you and cannot be shared with other PhAB users. A PhAB folder can be shared by several PhAB users. The predefined Widgets folder is a PhAB folder.


    Note: You need to have special permissions in order to create or to change a PhAB folder.

    Each folder pops up as a palette, beside the widget palette. You can view or hide them using Window-->Show Templates; this menu contains a list of all defined templates. When you launch PhAB, all the palettes pop up by default.

  5. You must provide a name and an icon for the template.

    Note: You can create an icon by clicking Icon Edit.

  6. Optionally, set the background color for the icon in the widget palette, and the resizing method (use original dimension or resize by dragging).
  7. If the widgets that you're saving as a template have callbacks attached, you can click on the Edit Callbacks button and set the callbacks to be saved in the template. By default, all the callbacks are saved. If the widgets you are saving don't have any callbacks attached, the Edit Callbacks button is disabled.

    You can specify whether PhAB prompts you with a list of included callbacks when you instantiate a template widget that contains callbacks. This setting is set on the General tab of the Preferences dialog under the When created widgets contain callbacks option. If you select Automatically add callbacks, all callbacks are added. If you select Ask me, PhAB prompts you with a list of callbacks that you can select from.

Adding a widget class

You can create a new widget template from scratch, without starting from an existing template. If there is no template available for a widget class (for example, if you just created a brand new widget class), then you must instantiate the widget, then create the a template from the widget instance. See the Building Custom Widgets guide for information about building a widget and creating a widget description table.

To instantiate a widget class and then create a template:

  1. Select Edit-->Add Widget Class. The following dialog appears:

    Add widget class step 1

  2. Enter the name of the new widget class and click Continue.

    PhAB scans the palette definition files for the widget's description table. Palette definition files (*.pal are listed in palette.def. If you have written a new *.pal file containing your widget's description table, you should add it to palette.def.

    If no widget definition is found, this dialog appears:

    Add widget class - no widget   definition found

  3. Once the new widget class's description table is found in one of the palette files, the following dialog is displayed:

    Add widget class step 2

  4. Customize the newly created widget, customize it, and use the Save Template to save the template.

Editing templates

You can change a template definition at any time by editing the templates. To edit an existing template:

  1. Choose Templates from the Edit menu.
  2. The Edit Templates dialog appears.
  3. Edit the template as desired and then save the results.

    You can change the template's name, the template's folder name, and the template's icon. Using drag and drop, you can move the templates between folders, and you can reorder the templates inside the same folder. Note that you can only move a template between folders of the same type (e.g. from a User folder to a User folder).

Deleting templates

To delete a template:

  1. Choose Edit Templates from the Edit menu.
  2. A dialog similar to that used to create a template is displayed.
  3. Choose the template folder, and click Delete.

Warning: main(/www/www/htdocs/style/footer.php) [function.main]: failed to open stream: No such file or directory in /www/www/docs/6.4.1/photon/prog_guide/widgets.html on line 2271

Warning: main() [function.include]: Failed opening '/www/www/htdocs/style/footer.php' for inclusion (include_path='.:/www/www/common:/www/www/php/lib/php') in /www/www/docs/6.4.1/photon/prog_guide/widgets.html on line 2271