Colours
Because you are accessing a 3270 mainframe host using the TN3270 emulation standard from a PC you can change the default colours of text and backgrounds to suit your preferences. Instead of the EGA limit of eight colours on real 3270 terminals you can use a rich palette of colours on your PC’s display.
You may want to change the defaults to conform to a special perception (such as, seeing yellow as red and red as yellow). You may want to change to colours that improve readability or visibility of text for you (such as green on black). The process described here is only limited by the colour settings for your PC display. The changes only affect the currently selected colour scheme.
Colour schemes allow you to create, set and save all available colour options for a session at once. You can save colour schemes and easily share them between multiple computers.
The colour dialog
The mainframe application can control the appearance of the display through the use of field and character attributes and a set of default colours defined in the TN3270 protocol. The colour options dialog allows you to redefine these default colours.
The components of the colour dialog
Selection - The field and colour selection panel. Use this to select which field type for which you want to change the colour, or which 3279 colour you want displayed differently. Each of the available options is displayed in it's current text and background colour
Colour Scheme - The ‘Colour Scheme’ section allows you to create new colour schemes, delete unwanted colour schemes, and assign an existing colour scheme to the current session.
Text or background - For each of the selections except the screen background colour you have the choice of changing the foreground (text) or the background colour by selecting the corresponding option.
Available Colours - The 16 basic EGA colours available on any colour monitor
Reset Colour - Reset the currently selected field type or 3279 colour to the default
Reset All Colours - Resets all field types, 3279 colours and the background colour to the default values
Set All Field Backgrounds to Screen Backgrounds - Sets the background colour for all fields to the current screen background
Always enable Base Colour Mode - Set the program to always use Base Colour Mode regardless of host preference
Choose Custom Colour - Allows you to select a custom colour depending on the capabilities of your video card and monitor colour depth. The following dialog box appears:
On this screen you have a choice of selecting from pre-define colours in "Basic colours:", or "Custom colours:" based upon the 256 colour rainbow picture to the right.
Changing the background colour only changes the background for the parts of the screen which are not defined by field or character attributes. If you want to have a consistent
Basic Colour Process
Click on any colour box in the "Basic colours:" collection.
The selected colour appears in the "Colour|Solid" field.
The data summaries for the colour include Hue (the number of the basic colour out of 256), Saturation (the amount of the primary color out of 255), and luminance (the brightness of the colour). The colour summaries include the quantity of Red, Green and Blue in each colour value, out of a maximum of 255.
To implement the displayed colour in the custom color box as your choice for the selection on the previous screen, click on OK, and return to the main colour dialog. To return the main colour dialog without changes, click on Cancel.
If you clicked on OK, you are returned to the Colour selection screen, where your choice is displayed in the Sample window.
Click on the Apply button to accept this colour, and go on selecting more colours.
If you want to return to the 3279 default colour for the selection, click on Default.
If you want to reset all your changes to the 3279 default colours, click on the "Reset All" button.
Click OK to accept all colour changes that have been made, whether applied or not, and exit the colour dialog. Click Cancel to reject all colour changes that have not been applied, and exit the colour dialog. In order to change applied colours, they must be re-selected and applied.
Frequent Colour Questions
How do I change a text colour?
This is best shown with an example. Let us assume you want to change some text on your screen that is displayed in green, and you would like to have it shown in red instead.
If we change a colour and then select ‘Apply’ or ‘OK’, the currently selected colour scheme will be updated, which may not be what you want, so before we change any colours, we first save the current colour scheme under a different name. That way, we can easily go back to the previous or the default scheme. Click the ‘Save As…’ button, and type a distinctive name for your colour scheme, then click Ok. The new colour scheme will automatically be selected in the list. Any changes we make now will be applied to the new scheme, leaving the old one unchanged.
The next step is to identify which colour you need to change. A colour on the 3270 screen can be there because
a. the text is part of a field and displayed in the field colour, or
b. the colour is directly assigned to one or more characters (3279 colours)
If the colour is part of a field, find out if the field is protected. Can you type where the unwanted colour is? If yes, the field is unprotected, otherwise it is protected. Let’s assume for this example that the field is protected.
Each field type is again divided into ‘bright’ and ‘dim’, so we can have either a 'Protected Dim' or a 'Protected Bright' field. Take a look at these two options in the colour dialog. Is either one displayed with green text? If so, that is the field type we need to change. If both are, we select one of the two at random in the selection list. If neither one is, we probably need to change a 3279 colour.
On the right, click on ‘Foreground’ and then select one of the 16 pre-defined colours, or click on the ‘More Colours’ button to choose a custom colour. Now click ‘Apply’.
If at this point the colour of the text on your screen has changed, you are done (or can go on to changing the next colour).
If the text you wanted to change is still displayed in the old colour, it is probably displayed in one of the 3279 colours, which can be assigned by the mainframe application programmer directly (bypassing the field colours for all or part of the screen). Still in the colours dialog, select the 3279 colour in the list that is displayed in the colour you want to change. Make sure ‘Foreground’ is selected, click on the replacement colour, then ‘Apply’.
If the colour still did not change, you probably have multiple fields or multiple 3279 colours defined to use the same colour, so you will need to repeat the above steps for other fields that also use the ‘green’ you want to change.
How do I change a field or character background?
Changing a background colour follows the same process as described above for changing text colour. You can set the background colour for each of the field types, as well as the 3279 colours. Just select the field type or colour you want to change, and make sure the ‘Background’ choice is selected. When the screen background option is selected, the ‘Background’ option is disabled.
How can I create a colour scheme?
Select a colour scheme that is close to what you are looking for, so that you don’t have to change too many colours. Then click the ‘Save As…’ button in the colours dialog, and choose a name for your colour scheme. The new scheme will be selected automatically. Now when you start changing colours, your new colour scheme will be changed. When you are happy with the new scheme, click OK or Apply to save the new colour scheme.
Colour schemes are simple text files, stored in your QWS3270 folder. You can easily share them with friends and co-workers; simply copy one or more files to the QWS3270 folder on a different computer.
Why can’t I save my colours? What does that error message mean?
The colour for ‘xyz fields’ matches the background colour you selected.
When you see a message similar to this then it means that one or more foreground (text) colours match one or more background colours, so you have effectively made some of the screen text invisible. If you select a green foreground for one field, selecting the same green for the field background, or for the screen background, would make the text in those fields invisible. The first field or 3279 colour that caused the error message will be selected after you dismiss the message.
To avoid this message, it is probably a good idea to first set the screen background colour to your preference. Then start choosing fore- and background colours for fields and 3279 colours.
Please note that the application does not prevent you from selecting (very) similar colours for text and backgrounds; please use your own good sense when making those choices.
I've changed my screen colours, how can I restore the defaults?
If your screen looks nothing like you imagined when you’re done, simply select the offending colour scheme, and click the ‘Reset All’ button in the colours dialog. To restore one particular colour to it’s default, select the colour or field type and click ‘Reset Colour’. Both fore- and background colours will be set to the defaults.