how to highlight text in tkinter? , do you know what i am doing wrong ?

[moroccanplaya]

hi i have text in a tkinter text widget, how would i highlight specific letters?

 
  Text.tag_config("s", background="yellow")
  Text.insert(END,("s"))
 
 
 

the code above just adds s to the end of the text, do you know what i am doing wrong ?

[bvdet]

You are telling Tkinter to insert text "s" at the end. The following will highlight a sequence of characters:

....snip....
        self.Btn1 = Tkinter.Button(self.mainFrame,
                                        text="Highlight 's'",
                                        command=lambda: self.highlight("s"))
        self.Btn1.grid(row=3, column=0, sticky="ns")
 
    def highlight(self, seq):
        if "highlight" in self.textWidget.tag_names():
            self.textWidget.tag_delete("highlight")
        i = len(seq)
        idx = "1.0"
        while True:
            idx = self.textWidget.search(seq, idx, nocase=1, stopindex='end')
            if idx:
                idx2 = self.textWidget.index("%s+%dc" % (idx, i))
                self.textWidget.tag_add("highlight", idx, idx2)
                self.textWidget.tag_config("highlight", background="yellow")
                idx = idx2
            else: return
....snip....

Maybe there's a better way?

[moroccanplaya]

is there any tutorial, or documentation on using tags and doing highlights in python 3 ?

i have tried this but its not working

def highlight(seq):
    if "highlight" in Text.tag_names():
        Text.tag_delete("highlight")
 
        i = len(seq)
        index = "1.0"
        while True:
            index = Text.search(seq, index, nocase=1, stopindex='end')
            if index:
                index2 = Text.index("%s+%d" % (index, i))
                Text.tag_add("highlight", index, index2)
                Text.tag_config("highlight", background="yellow")
                index = index2
            else: return
 

[moroccanplaya]

as im trying to highlight white spaces, is there away of highlighting in a for loop, for example for " " in ttk.Text, highlight in yellow ??

[bvdet]

You can highlight any sequence of text, including a space character, with the code I posted.

[moroccanplaya]

i tried to modify the code, but something went wrong it is not highlighting anything

def highlight(seq):
 
    if "highlight" in Text.tag_names():
        Text.tag_delete("highlight")
 
        i = len(seq)
        index = "1.0"
        while True:
            index = Text.search(seq, index, nocase=1, stopindex='end')
            if index:
                index2 = Text.index("%s+%d" % (index, i))
                Text.tag_add("highlight", index, index2)
                Text.tag_config("highlight", background="yellow")
                index = index2
            else: return 
 
 
 

[bvdet]

It's possible the ttk.Text widget doesn't work like a Tkinter.Text widget. Following is the complete code for a Tkinter Text widget with a button to highlight the text "bolt". It works in Python 2.7.2.

import Tkinter
"""
Edit a file and save the text.
"""
 
textFont1 = ("Courier New", 16, "normal")
 
class ScrollbarX(Tkinter.Scrollbar):
    def set(self, low, high):
        if float(low) <= 0.0 and float(high) >= 1.0:
            self.grid_remove()
        else:
            self.grid()
        Tkinter.Scrollbar.set(self, low, high)
 
class App(Tkinter.Tk):
    def __init__(self, fn, fnout):
        Tkinter.Tk.__init__(self)
        self.title("Text Widget")
        self.fin = open(fn, 'r')
        self.fnout = fnout
        self.mainFrame = Tkinter.Frame(self)
 
        top=self.winfo_toplevel()
        top.columnconfigure(0, weight=1)
        top.rowconfigure(0, weight=1)
 
        self.mainFrame.grid(row=0, column=0, sticky="nsew")
        self.exit = Tkinter.Button(self.mainFrame,
                                   text="Save and Exit",
                                   command=self.finish)
        self.exit.grid(row=0, column=0, sticky="ns")
 
 
        self.mainFrame.columnconfigure(0, weight=1)
        self.mainFrame.rowconfigure(1, weight=1)
 
        vscrollbar = ScrollbarX(self.mainFrame)
        vscrollbar.grid(row=1, column=1, sticky="ns")
        hscrollbar = ScrollbarX(self.mainFrame, orient=Tkinter.HORIZONTAL)
        hscrollbar.grid(row=2, column=0, sticky="ew")
 
        self.textWidget = Tkinter.Text(self.mainFrame,
                                       yscrollcommand=vscrollbar.set,
                                       xscrollcommand=hscrollbar.set,
                                       wrap=Tkinter.NONE,
                                       height=24,
                                       width=60,
                                       font=textFont1)
        self.textWidget.insert("1.0", self.fin.read())
        self.textWidget.grid(row=1, column=0, sticky="nsew")
 
        hscrollbar["command"] = self.textWidget.xview
        vscrollbar["command"] = self.textWidget.yview
 
        self.Btn1 = Tkinter.Button(self.mainFrame,
                                        text="Highlight 'bolt'",
                                        command=lambda: self.highlight("bolt"))
        self.Btn1.grid(row=3, column=0, sticky="ns")
 
    def finish(self):
        fout = open(self.fnout, 'w')
        fout.write(self.textWidget.get("1.0", "end"))
        fout.close()
        self.fin.close()
        app.destroy()
 
    def highlight(self, seq):
        if "highlight" in self.textWidget.tag_names():
            self.textWidget.tag_delete("highlight")
        i = len(seq)
        idx = "1.0"
        while True:
            idx = self.textWidget.search(seq, idx, nocase=1, stopindex='end')
            if idx:
                idx2 = self.textWidget.index("%s+%dc" % (idx, i))
                self.textWidget.tag_add("highlight", idx, idx2)
                self.textWidget.tag_config("highlight", background="yellow")
                idx = idx2
            else: return
 
if __name__ == "__main__":
    fn = "text1.txt"
    fnout = "text2.txt"
    app = App(fn, fnout)
    app.mainloop()

[moroccanplaya]

im using tkinter.Text widget ?, im confused, so the example wont work in python 3

[bvdet]

Since I don't have Python 3 installed, there is no way for me to test it. I believe it can easily be converted though. Replace every occurrence of "Tkinter" with "tkinter". That should take care of most if not all of it.

[moroccanplaya]

yeah i replaced it and the program does work in python 3, i'm struggling to understand how the highlighting is done in that program, still cant get the highlighting to work in my program

[bvdet]

Function highlight() basically works like this:

1. If the Text widget has a tag named "highlight", delete all occurrences
2. Save the length of the text string "seq"
3. Set the starting index of the widget to "1.0"
4. Start a loop
5. Use Text widget method "search" to find the next occurrence of "seq"
6. If no occurrence of "seq", return
7. If there is an occurrence, calculate the next index from the old index and the length of "seq"
8. Add a tag named "highlight" from idx to idx2
9. Configure the tag "yellow"
10. Reassign idx to idx2

[moroccanplaya]

so basically i think the highlight function is not working with my button

[moroccanplaya]

button4 = ttk.Button(content,text="highlight", command=lambda: highlight(" "))

[bvdet]

moroccanplaya - That should work. If it doesn't, there is something else wrong.

[moroccanplaya]

i have used the same highlight function as in the example you gave me i just removed the self and tried using both tkinter.text and textWidget to see if they work, i used

if "highlight" in tkinter.Text.tag_names():

and i revived an error stating that tag_names takes at least 1 argument

then i changed it back just to :

 if "highlight" in Text.tag_names():

i get no error