MapInfo Pro

Happy #mapinfomonday 

In this post, I will show you how you can use an individual theme to apply styles to your layer based on an attribute. I'll also give a few hints about some other benefits this will give you. 

My post a few weeks back on setting styles for new features for a layer, raised some questions from @Mark McGovern around which is the best approach when styling features in a layer: object styles saved to the table potential using the new features, using a layer override style or applying a theme of some kind to the layer.

So let me start this article with a question: Do you have a favorite way of styling your layer? Are you using object styles saved to the table, layer overrides set at the layer level, or do you apply a theme to your layer for styling?

Styling a Layer via an Individual Theme

The first thing to know is that in order to use an individual theme to style your layer, you will need some attribute information. That can be based on the type of feature, "Highway", "Motorway", or "Major Road" as an example, or you can use a status field for this, "Planned", "Existing", or "To be renovated" and similar. Or you could use the year of construction or the material used for the feature. These are just a few examples.

In my example, I have a table of cables with an attribute for status that I want to use for my style. You can see the cable layer in the map below, shown with a thin dotted red line. Currently, the Status column holds two values: "Existing" and "Planned".

From the Map tab, I select Add Theme from the Content group. 

In the Create Thematic Map - Step 1 of 3 dialog, I select Individual as the thematic type and a template for lines and click on the button Next >. 

In the dialog Create Thematic Map - Step 2 of 3, I select the layer and the column to use.

In the final dialog, Create Thematic Map - Step 3 of 3, I modify the style to meet my requirements, and I also change the legend slightly.

Afterward, I click on the Legend button and modify the legend slightly.

As I could foresee the need to use this again thematic at a later stage, I decide to create a template with these settings. To do so, I click on the Save As button in the Template group at the lower right side of the dialog.

For individual themes, it often makes sense to also check the Save Individual Value Categories option. This will link the values to the styles in the template and ensure the same style is applied to the same value the next time you use this template.

If you forget to save the theme to a template, you can always go back and do this by modifying an existing thematic layer.

In the dialog Create Thematic Map - Step 3 of 3, I click the OK button to apply my theme to the layer. This results in a couple of changes.

1. The Individual Theme Layer has been added to the Layer List on top of the existing Cable layer resulting in a new style for the cables on the map.
2. Under the added individual layer, you can see the values found in the Status column shown as the legends I modified and with their style next to them. This acts as a simple legend.
3. A Legend window has also appeared holding the same legend details as I can see in the Layer List.

As I have a legend in my Layer List, I decide to close the additional legend window. I also right-click the individual thematic layer in the Layer List to rename it to a friendlier name, like Cable Status.

A few Benefits of the Indivdual Theme Worth Mentioning

Using an individual theme to style your layer comes with a few benefits.

First, you can use the Layer List to turn on and off individual elements of the layer. Say I wanted to only focus on the existing cable for a certain work I needed to do. From the Layer List, I can simply uncheck the Visible option for the Planned Cable value and they won't be displayed on the map.

Secondly, as the status of the cables changes, the style will automatically change too. If I change the status of a cable from Planned to Existing, the style for that feature will also change when a refresh is forced through by for example switching back to the map window from the Info window.

This works if I change the values one by one through the Info window, or if I perform a batch update through the dialog Update Column.

One Thing to Watch Out for

If you at some point add additional status values to your column, this will affect the display of the thematic layer too. First, it will show these as All Others as the layer hasn't been set up to handle these values. In the image below, I have added an additional value, To be Repaired, to a few records. Notice how they appear with a black thin line in the map and as "all others" in the Layer List.

In order to get this new value included, you will need to recreate your thematic map, potentially using your template as this already holds the style information for the existing values. If you didn't save the template when you created the thematic layer, now is the time to create a template from your thematic layer as it will make sure the existing styles are assigned to the existing values.

When you select your template, remember to check the options to Use Customized Legend Text and Use Individual Categories. This will use the style for the values you saved and apply your custom legends too.

In the last step, you just need to set the style and potentially the legend for the newly added value(s).

And now the new value is also shown in the legend and in the Layer List.

I hope you find this useful. It is a nice way to link the values from a column to the style shown on the map.

------------------------------
Peter Horsbøll Møller
Principal Presales Consultant | Distinguished Engineer
Precisely | Trust in Data
------------------------------

Hi Peter,

I wanted to ask a question about the way the Theme Templates are stored, particularly for the custom themes. I've recently gone through the process to update MI v2021 to build 33 (for the security update), and upon using the themes, a lot of my custom created ones are now only shown by an ID number e.g. 0089 etc rather than a named title.

Is there a way to be able to edit these within the AppData (.thm) location? I have attempted to copy over the backed up version of the ThemeTemplate.lst, which was automatically backed up during the update process, but each time I try to load MI, it reverts back.

Some of my templates are old but still very useful, so having the named title would be preferable.

Below is how they are displayed in application as well as the Theme lists from the current state (right) and the backed up version (left).

I don't mind tinkering behind the scenes, having done this with named views and Layout Templates, but having tried to use one of these and then save the template, it creates a new one rather than overwrite it, and there doesn't seem to be a "delete Theme" button or option.

Also, many of these themes are used in various workspaces, used on a regular basis, is the Theme Name used within the workspace or does it recall the individual value and style used?

As I can't find an option to edit these within the application, I've created this within the Ideas portal (https://ideas.precisely.com/ideas/MIPRO-I-1445). Maybe this could be something added to the future development of MapInfo.

------------------------------
James King
Essex County Council
CHELMSFORD

Original Message:
Sent: 02-27-2023 03:09
From: Peter Møller
Subject: MapInfo Monday: Styling a Layer through an Individual Theme

Happy #mapinfomonday 

In this post, I will show you how you can use an individual theme to apply styles to your layer based on an attribute. I'll also give a few hints about some other benefits this will give you. 

My post a few weeks back on setting styles for new features for a layer, raised some questions from @Mark McGovern around which is the best approach when styling features in a layer: object styles saved to the table potential using the new features, using a layer override style or applying a theme of some kind to the layer.

So let me start this article with a question: Do you have a favorite way of styling your layer? Are you using object styles saved to the table, layer overrides set at the layer level, or do you apply a theme to your layer for styling?

Styling a Layer via an Individual Theme

The first thing to know is that in order to use an individual theme to style your layer, you will need some attribute information. That can be based on the type of feature, "Highway", "Motorway", or "Major Road" as an example, or you can use a status field for this, "Planned", "Existing", or "To be renovated" and similar. Or you could use the year of construction or the material used for the feature. These are just a few examples.

In my example, I have a table of cables with an attribute for status that I want to use for my style. You can see the cable layer in the map below, shown with a thin dotted red line. Currently, the Status column holds two values: "Existing" and "Planned".

From the Map tab, I select Add Theme from the Content group. 

In the Create Thematic Map - Step 1 of 3 dialog, I select Individual as the thematic type and a template for lines and click on the button Next >. 

In the dialog Create Thematic Map - Step 2 of 3, I select the layer and the column to use.

In the final dialog, Create Thematic Map - Step 3 of 3, I modify the style to meet my requirements, and I also change the legend slightly.

Afterward, I click on the Legend button and modify the legend slightly.

As I could foresee the need to use this again thematic at a later stage, I decide to create a template with these settings. To do so, I click on the Save As button in the Template group at the lower right side of the dialog.

For individual themes, it often makes sense to also check the Save Individual Value Categories option. This will link the values to the styles in the template and ensure the same style is applied to the same value the next time you use this template.

If you forget to save the theme to a template, you can always go back and do this by modifying an existing thematic layer.

In the dialog Create Thematic Map - Step 3 of 3, I click the OK button to apply my theme to the layer. This results in a couple of changes.

1. The Individual Theme Layer has been added to the Layer List on top of the existing Cable layer resulting in a new style for the cables on the map.
2. Under the added individual layer, you can see the values found in the Status column shown as the legends I modified and with their style next to them. This acts as a simple legend.
3. A Legend window has also appeared holding the same legend details as I can see in the Layer List.

As I have a legend in my Layer List, I decide to close the additional legend window. I also right-click the individual thematic layer in the Layer List to rename it to a friendlier name, like Cable Status.

A few Benefits of the Indivdual Theme Worth Mentioning

Using an individual theme to style your layer comes with a few benefits.

First, you can use the Layer List to turn on and off individual elements of the layer. Say I wanted to only focus on the existing cable for a certain work I needed to do. From the Layer List, I can simply uncheck the Visible option for the Planned Cable value and they won't be displayed on the map.

Secondly, as the status of the cables changes, the style will automatically change too. If I change the status of a cable from Planned to Existing, the style for that feature will also change when a refresh is forced through by for example switching back to the map window from the Info window.

This works if I change the values one by one through the Info window, or if I perform a batch update through the dialog Update Column.

One Thing to Watch Out for

If you at some point add additional status values to your column, this will affect the display of the thematic layer too. First, it will show these as All Others as the layer hasn't been set up to handle these values. In the image below, I have added an additional value, To be Repaired, to a few records. Notice how they appear with a black thin line in the map and as "all others" in the Layer List.

In order to get this new value included, you will need to recreate your thematic map, potentially using your template as this already holds the style information for the existing values. If you didn't save the template when you created the thematic layer, now is the time to create a template from your thematic layer as it will make sure the existing styles are assigned to the existing values.

When you select your template, remember to check the options to Use Customized Legend Text and Use Individual Categories. This will use the style for the values you saved and apply your custom legends too.

In the last step, you just need to set the style and potentially the legend for the newly added value(s).

And now the new value is also shown in the legend and in the Layer List.

I hope you find this useful. It is a nice way to link the values from a column to the style shown on the map.

------------------------------
Peter Horsbøll Møller
Principal Presales Consultant | Distinguished Engineer
Precisely | Trust in Data
------------------------------

Hi Peter,

I wanted to ask a question about the way the Theme Templates are stored, particularly for the custom themes. I've recently gone through the process to update MI v2021 to build 33 (for the security update), and upon using the themes, a lot of my custom created ones are now only shown by an ID number e.g. 0089 etc rather than a named title.

Is there a way to be able to edit these within the AppData (.thm) location? I have attempted to copy over the backed up version of the ThemeTemplate.lst, which was automatically backed up during the update process, but each time I try to load MI, it reverts back.

Some of my templates are old but still very useful, so having the named title would be preferable.

Below is how they are displayed in application as well as the Theme lists from the current state (right) and the backed up version (left).

I don't mind tinkering behind the scenes, having done this with named views and Layout Templates, but having tried to use one of these and then save the template, it creates a new one rather than overwrite it, and there doesn't seem to be a "delete Theme" button or option.

Also, many of these themes are used in various workspaces, used on a regular basis, is the Theme Name used within the workspace or does it recall the individual value and style used?

As I can't find an option to edit these within the application, I've created this within the Ideas portal (https://ideas.precisely.com/ideas/MIPRO-I-1445). Maybe this could be something added to the future development of MapInfo.

------------------------------
James King
Essex County Council
CHELMSFORD

Original Message:
Sent: 02-27-2023 03:09
From: Peter Møller
Subject: MapInfo Monday: Styling a Layer through an Individual Theme

Happy #mapinfomonday 

In this post, I will show you how you can use an individual theme to apply styles to your layer based on an attribute. I'll also give a few hints about some other benefits this will give you. 

My post a few weeks back on setting styles for new features for a layer, raised some questions from @Mark McGovern around which is the best approach when styling features in a layer: object styles saved to the table potential using the new features, using a layer override style or applying a theme of some kind to the layer.

So let me start this article with a question: Do you have a favorite way of styling your layer? Are you using object styles saved to the table, layer overrides set at the layer level, or do you apply a theme to your layer for styling?

Styling a Layer via an Individual Theme

The first thing to know is that in order to use an individual theme to style your layer, you will need some attribute information. That can be based on the type of feature, "Highway", "Motorway", or "Major Road" as an example, or you can use a status field for this, "Planned", "Existing", or "To be renovated" and similar. Or you could use the year of construction or the material used for the feature. These are just a few examples.

In my example, I have a table of cables with an attribute for status that I want to use for my style. You can see the cable layer in the map below, shown with a thin dotted red line. Currently, the Status column holds two values: "Existing" and "Planned".

From the Map tab, I select Add Theme from the Content group. 

In the Create Thematic Map - Step 1 of 3 dialog, I select Individual as the thematic type and a template for lines and click on the button Next >. 

In the dialog Create Thematic Map - Step 2 of 3, I select the layer and the column to use.

In the final dialog, Create Thematic Map - Step 3 of 3, I modify the style to meet my requirements, and I also change the legend slightly.

Afterward, I click on the Legend button and modify the legend slightly.

As I could foresee the need to use this again thematic at a later stage, I decide to create a template with these settings. To do so, I click on the Save As button in the Template group at the lower right side of the dialog.

For individual themes, it often makes sense to also check the Save Individual Value Categories option. This will link the values to the styles in the template and ensure the same style is applied to the same value the next time you use this template.

If you forget to save the theme to a template, you can always go back and do this by modifying an existing thematic layer.

In the dialog Create Thematic Map - Step 3 of 3, I click the OK button to apply my theme to the layer. This results in a couple of changes.

1. The Individual Theme Layer has been added to the Layer List on top of the existing Cable layer resulting in a new style for the cables on the map.
2. Under the added individual layer, you can see the values found in the Status column shown as the legends I modified and with their style next to them. This acts as a simple legend.
3. A Legend window has also appeared holding the same legend details as I can see in the Layer List.

As I have a legend in my Layer List, I decide to close the additional legend window. I also right-click the individual thematic layer in the Layer List to rename it to a friendlier name, like Cable Status.

A few Benefits of the Indivdual Theme Worth Mentioning

Using an individual theme to style your layer comes with a few benefits.

First, you can use the Layer List to turn on and off individual elements of the layer. Say I wanted to only focus on the existing cable for a certain work I needed to do. From the Layer List, I can simply uncheck the Visible option for the Planned Cable value and they won't be displayed on the map.

Secondly, as the status of the cables changes, the style will automatically change too. If I change the status of a cable from Planned to Existing, the style for that feature will also change when a refresh is forced through by for example switching back to the map window from the Info window.

This works if I change the values one by one through the Info window, or if I perform a batch update through the dialog Update Column.

One Thing to Watch Out for

If you at some point add additional status values to your column, this will affect the display of the thematic layer too. First, it will show these as All Others as the layer hasn't been set up to handle these values. In the image below, I have added an additional value, To be Repaired, to a few records. Notice how they appear with a black thin line in the map and as "all others" in the Layer List.

In order to get this new value included, you will need to recreate your thematic map, potentially using your template as this already holds the style information for the existing values. If you didn't save the template when you created the thematic layer, now is the time to create a template from your thematic layer as it will make sure the existing styles are assigned to the existing values.

When you select your template, remember to check the options to Use Customized Legend Text and Use Individual Categories. This will use the style for the values you saved and apply your custom legends too.

In the last step, you just need to set the style and potentially the legend for the newly added value(s).

And now the new value is also shown in the legend and in the Layer List.

I hope you find this useful. It is a nice way to link the values from a column to the style shown on the map.

------------------------------
Peter Horsbøll Møller
Principal Presales Consultant | Distinguished Engineer
Precisely | Trust in Data
------------------------------