如何分别从文本小部件检索行

Question

I am trying to retrieve each new line in a text widget separately, I have 3 instances of Container class, the first instance prints data as expected but for second instance duplicates of first line are returned

I am using object.get('current linestart', 'current lineend') to return new lines separately

full code: https://pastebin.com/mLR3zbFg

class Container(tk.Frame):
    def __init__(self, parent = None, priority = 3, bg = 'bisque'):
        self.inpList = []
        self.b = tk.Button(self.f, text = 'add', command = lambda: self.add_task(priority))
    def add_task(self, priority): # refer 1.2_text for implementation
        finished = False
        self.t = tk.Text(self.f)
        self.t.configure(height = 10, wrap = 'word')
        self.t.bind("<Return>", self.save_task)
        self.t.pack(fill = tk.X)


def print_all(self):
    print(self.inpList)

def save_task(self, event):
    td = self.t.get('current linestart', 'current lineend')
    self.inpList.append(td)

if __name__ == '__main__':
    window = tk.Tk()
    window.minsize(300, 600)

    p1 = Container(window, priority = 1)
    p2 = Container(window, bg = 'blue', priority = 2)
    p3 = Container(window, bg = 'red', priority = 3)

    window.mainloop()

Answer 1

figbeam's answer could work, but it wouldn't be great if you had a lot of text inputted and it seems like you want to read each line individually. Here's a better solution in my opinion:

According to the docs , current doesn't seem to do what you expect; namely, current will give you to the character closest to your mouse (and only if you actually move your mouse). This could be a reason why you were noticing weird behavior for the widgets that were below but not the one on top.

A better solution is to move to the end of the text, then up one line, and then use the linestart and lineend selectors you had prior. Namely change

td = self.t.get('current linestart', 'current lineend')

to

td = self.t.get('end - 1 lines linestart', 'end - 1 lines lineend')

Things should work as expected after this change!

Answer 2

Is it necessary to read each line separately? Otherwise you could read the lines into a list and then work with the list items separately.

As far as I can tell the delimiter for lines is newline, which can make it look odd if you use wrap.

Here's an example of reading multiple lines into a list:

line_list = textbox.get('1.0', 'end').split('\n')
for line in line_list:
    # Process line

Just a thought.

Answer 3

The line td = self.t.get('current linestart', 'current lineend') doesn't work as expected. One solution is to read the whole content of the text box at each update (as suggested also in https://stackoverflow.com/a/55739714/2314737 ).

In the code substitute the function save_task() with:

def save_task(self, event):
    td = self.t.get("1.0",'end').rstrip()
    self.inpList = td.split('\n')

This also takes care of any deleted lines that otherwise will stay in td .

See also this similar question: How to read the input(line by line) from a multiline Tkinter Textbox in Python?