Get all tags associated with a tkinter text widget

Tkinter, a popular GUI toolkit for Python, provides a versatile Text widget that allows developers to display and edit text in their applications. One powerful feature of the Tkinter Text widget is its ability to apply tags to specific ranges of text. Tags in Tkinter provide a way to associate metadata or formatting information with a portion of the text, allowing for dynamic and interactive user interfaces. In this article, we will highlight the concept of tagging in Tkinter Text widgets.

Understanding Tags in Tkinter

In Tkinter, a tag is essentially a named entity that can be associated with a range of text within the Text widget. Tags enable developers to apply formatting, define behavior, or categorize specific portions of text. While the Text widget itself doesn't have inherent tags, you can create and manage them dynamically during runtime.

Adding Tags to Text

To add a tag to a range of text, the tag_add method is used. This method requires the tag name and the starting and ending indices of the text range to be tagged. Let's consider an example −

Example

# importing necessary libraries
import tkinter as tk

def add_tag(text_widget, start_index, end_index, tag_name):
   text_widget.tag_add(tag_name, start_index, end_index)

# Create a Tkinter window
root = tk.Tk()
root.title("Adding Tags to Text")
root.geometry("720x250")


# Create a Text widget
text_widget = tk.Text(root)
text_widget.pack()

# Insert some text into the Text widget
text_widget.insert(tk.END, "This is some text. Click here to highlight.")

# Add a tag to a specific range of text
add_tag(text_widget, "1.0", "1.4", "tag1")

# Start the Tkinter event loop
root.mainloop()

In this example, the add_tag function is used to add a tag named "tag1" to the range of text from index "1.0" to "1.4". The tag is then associated with this specific portion of text.

Output

On executing the code, you will get the following output window −

Retrieving Tags

To retrieve all tags associated with the Text widget, the tag_names method is employed. This method returns a tuple containing the names of all tags present in the widget. Here's an example −

Example

# importing necessary libraries
import tkinter as tk

def get_all_tags(text_widget):
   all_tags = text_widget.tag_names()
   return all_tags

# Create a Tkinter window
root = tk.Tk()
root.title("Retreiving Tags")
root.geometry("720x250")

# Create a Text widget
text_widget = tk.Text(root)
text_widget.pack()

# Insert some text into the Text widget
text_widget.insert(tk.END, "This is some text. Click here to highlight.")

# Add a tag to a specific range of text
text_widget.tag_add("tag1", "1.0", "1.4")

# Get all tags associated with the Text widget
all_tags = get_all_tags(text_widget)
print("All tags:", all_tags)

# Start the Tkinter event loop
root.mainloop()

Output

In this example, the get_all_tags function retrieves and prints all tags associated with the Text widget.

Applying Multiple Tags

Developers often need to apply multiple tags to different ranges of text within the same Text widget. This can be achieved by using the tag_add method multiple times with different tag names and text ranges.

Consider the following example −

Example

# importing necessary libraries
import tkinter as tk

def get_all_tags(text_widget):
   # Get all tags in the Text widget
   all_tags = text_widget.tag_names()
   return all_tags

def add_tag(text_widget, start_index, end_index, tag_name):
   # Add a tag to a specified range of text in the Text widget
   text_widget.tag_add(tag_name, start_index, end_index)

# Create a Tkinter window
root = tk.Tk()
root.title("Adding Multiple Tags")
root.geometry("720x250")

# Create a Text widget
text_widget = tk.Text(root)
text_widget.pack()

# Insert some text into the Text widget
text_widget.insert(tk.END, "This is TutorialsPoint.com.")

# Add tags to different ranges of text
add_tag(text_widget, "1.0", "1.4", "tag1")
add_tag(text_widget, "1.20", "1.25", "tag2")
add_tag(text_widget, "1.30", "1.37", "tag3")

# Get all tags associated with the Text widget
all_tags = get_all_tags(text_widget)
print("All tags:", all_tags)

# Start the Tkinter event loop
root.mainloop()

In this example, three different tags (tag1, tag2, and tag3) are added to specific ranges of text within the Text widget. The get_all_tags function then retrieves and prints all the tags associated with the Text widget. You can customize the ranges and tags based on your specific use case.

Output

Upon running the code, you will get to see the following output window −

Conclusion

Tkinter's Text widget, with its tagging system, can help developers create dynamic and interactive user interfaces. Tags offer flexibility for formatting, categorizing content, and responding to user interactions. By mastering the addition and retrieval of tags, developers can unlock the full potential of Tkinter, enhancing the functionality of their text-based applications.