Elizabeth Smith wrote a very interesting blog article on October 6, 2008 titled "Treeviews and Cell Renderer Properties - Practical PHP-GTK". I only saw it today, and found this very interesting and useful.

Although she has only showed an example of how to change the background color of a single cell in a treeview, the method can be applied to a lot of situations in treeview. Instead of using a custom dispay function, you can actually do it right inside a tree store or list store.

However, this does not mean that you can now throw the custom display function out of the window. You will find that in many situations, you will still need to use the custom display function.

In order to understand when to use the custom display function, and when you can use Elizabeth's method, I think the best way is to let you see how the two methods are used in practice.

In the next couple of sample codes, you will see how I transform some of the treeview sample codes I've written in the past and achieve the same result using Elizabeth's method. I would strongly encourage you to compare the two sample codes so that you understand the differences and similarities between the two methods.

The first example I'll show is the display of a list view in alternate row colors.

First take a look at the sample code using the custom display function: How to display a 2D array in GtkTreeView - Part 3 - with alternate row colors?

Then study the sample code below that uses Elizabeth's method. Both will produce the sample output as shown below:

This is another PHP-GTK/Glade trick contributed by Dysmas de Lassus of France.

When you're using PHP-GTK with Glade, normally we use the following to load the pointer to the widget 'entry1' defined in the glade file:

$glade->get_widget('entry1');

Dysmas found it "bored" to have to load each widget one by one.

So he found a way that allows him to load all the widgets defined in a glade file all at once into an array using just two lines as shown below:

This is another undocumented PHP-GTK2 feature discovered by Dysmas de Lassus of France.

In the article How to setup combobox with multi level options - Part 1 - display as tree structure? Dysmas showed us how to display a multi-level options in a combobox using a GtkTreeStore as shown below:

Dysmas found out by adding just one more line, you can display the same multi-level options in the form of a hierarchical sub-menus as shown below:

This is contributed by Dysmas de Lassus of France.

In the article How to setup and process GtkComboBox? we use a GtkListStore to store the options.

Dysmas found out that if you use a GtkTreeStore instead of a GtkListStore, you can actually display a multi-level options as shown below. Interesting, huh!

I've showed you how to dispay a tree structure from an array in the article How to display a tree structure from array? In that example, defining the tree and each node is quite troublesome.

Suppose you would like to be able to define a tree as simple as the following:

Level 1
+ level 1.1
++ level 1.1.1
++ level 1.1.2
++ level 1.1.3
+++ level 1.1.3.1
+ level 1.2
++ level 1.2.1
++ level 1.2.2
+ level 1.3

This example shows you how to process such a tree definition and populate them into a GtkTreeView as shown below.

Note: For a practical use of this tree definition, you may want to refer to How to setup combobox with multi level options - Part 1 - display as tree structure?

This is in response to Vacendak's post titled "Networking Questions".

He would like to see how a PING application is done using PHP-GTK2. So here it is.

This sample code also shows you how you can retrieve the "output" from a command window and pipe it into your php-gtk application as shown below:

This is in response to Peter's post titled "The opposite to GtkTable::attach()".

He would like to be able to unattach a cell content and replace the cell with some other widgets.

In particular, he has an original widget that spans from columns 14 to 20. He wants to replace this widget with one that spans columns 15 and 16 and a second one that spans columns 18-20. column 17 is to remain empty.

In Part 1, I've showed you how to replace a single cell widget with another single cell widget.

In this Part 2, I will show you how to handle Peter's case with widgets that span across multiple rows and columns. For this case, you cannot use the technique as described in Part 1 because each vbox may now span across different rows and columns.

When you first run the sample code, you will see some of the GtkLabel's spanning across some rows and columns.

When you click the button "Remove first two rows", the GtkLabel's of all the cells in the first two rows will be removed as shown below:

When you click the button "Replace first two rows", the GtkLabel's of the cells in the first two rows will be replaced with some other GtkLabel's that span across different rows and columns as shown below:

This is in response to Peter's post titled "The opposite to GtkTable::attach()".

He would like to be able to unattach a cell content and replace the cell with some other widgets.

In particular, he has an original widget that spans from columns 14 to 20. He wants to replace this widget with one that spans columns 15 and 16 and a second one that spans columns 18-20. column 17 is to remain empty.

In this Part 1, I will first show you how to replace a single cell widget with another single cell widget. We will deal specifically with Peter's case in Part 2.

When you first run the sample code, each cell of the GtkTable contains a GtkLabel.

When you click the button "Remove first two rows", the GtkLabel's of all the cells in the first two rows will be removed as shown below:

When you click the button "Replace first two rows", the GtkLabel's of all the cells in the first two rows will be replaced with GtkEtnry's as shown below:

This is in response to Peter's post titled "extending GtkSpinButton".

He would like to extend the GtkSpinButton class as shown below:

This is in response to Tropico's post titled "Finding first gtkentry widget into GtkNotebook page".

He would like to grab_focus on the first GtkEntry widget of one page of the notebook when the page becomes active as shown below:

This is in response to Vadi's post titled "How to make a popup menu on a GtkToolbar".

He would like to create a popup menu when a user right-click on a GtkToolbar as shown below:

This is in response to Neil's post titled "Get co-ordnates".

He would like to find the position (x,y co-ordinates) of an eventbox, or a label as shown below:

This is in response to Mote's post titled "2 questions about GtkImage".

He has set up an application that allows drag-and-drop of 12 different images. And he would like to be able to retrieve the URI (or filenames) of these 12 images at some later time for processing.

In Part 1, you can only drag and drop one image at a time.

In Part 2, you can drag and drop multiple images at one go.

In Part 3, you can delete unwanted images with right mouse click.

In Part 4, images will be automatically scaled to 100 by 100 pixels if the image is larger than 100 by 100 pixels.

In this Part 5, I'll show you how to display the image's URI in tooltip when the user hovers its mouse over an image as shown below:

This is in response to Mote's post titled "2 questions about GtkImage".

He has set up an application that allows drag-and-drop of 12 different images. And he would like to be able to retrieve the URI (or filenames) of these 12 images at some later time for processing.

In Part 1, you can only drag and drop one image at a time.

In Part 2, you can drag and drop multiple images at one go.

In Part 3, you can delete unwanted images with right mouse click.

In this Part 4, I'll show you how to automatically scale the image to size 100 by 100 pixels (when the width of height is greater than the 100 x 100) as shown below:

This is in response to Mote's post titled "2 questions about GtkImage".

He has set up an application that allows drag-and-drop of 12 different images. And he would like to be able to retrieve the URI (or filenames) of these 12 images at some later time for processing.

In Part 1, you can only drag and drop one image at a time.

In Part 2, you can drag and drop multiple images at one go.

In this Part 3, I'll show you how you can delete an image with right mouse click as shown below:

This is in response to Mote's post titled "2 questions about GtkImage".

He has set up an application that allows drag-and-drop of 12 different images. And he would like to be able to retrieve the URI (or filenames) of these 12 images at some later time for processing.

In Part 1, you can only drag and drop one image at a time.

In this Part 2, you can now drag and drop multiple files at one go as shown below:

This is in response to Mote's post titled "2 questions about GtkImage".

He has set up an application that allows drag-and-drop of 12 different images. And he would like to be able to retrieve the URI (or filenames) of these 12 images at some later time for processing.

In this Part 1, I will show you how to keep track of the filenames of the 12 images as shown below:

Setting the foreground or background color of a row in a treeview is easy.

The "more challenging" part is actually specifying the default foreground/background color for all the other rows that you do not want to highlight.

We have seen how to set the default foreground color in How to change the foreground color of some rows or columns in treeview?

In this example, I'll show you how to specify the "default background color" in a treeview as shown below:

In the article How to change the font of some rows or columns in treeview? I shared with you how specify "default font" in a treeview.

However, that method only works when you change the font to a different font, and want to change it back to the default font.

Suppose you only want to change the foreground color of some of the rows. You want the rest of the rows to use the default foreground color. You will find that the method described in How to change the font of some rows or columns in treeview? will not work in this case.

In this example, I'll show you how to specify the "default foreground color" in a treeview.

This is a recent "trick" that I've found with regards to treeview.

I've showed you how to change the font size of the row contents in a treeview in How to change the font size in GtkTreeView - Part 2?

Suppose you only want to change the font of some of the rows. You want the rest of the rows to use the default font.

In this example, I'll show you how to specify the "default font" in a treeview.