Write values from Pandas DataFrame columns into tkinter TreeView/Table Columns - python-3.x

Question

I want to write values from a dataframe into a tkinter treeview/Table, I am not able to do this.
my code:
#Setting up tkinter window.
root = Tk()
tree = ttk.Treeview(root)
#taking file input through a dialog box from the user.
file = filedialog.askopenfile(parent=root,mode='rb',title='Choose a xlsx file')
#readinf the excel file selected by the user and then creating a dataframe of that file.
xls = pd.read_excel(file)
df = pd.DataFrame(xls)
#taking all the columns heading in a variable"df_col".
df_col = df.columns.values
#all the column name are generated dynamically.
tree["columns"]=(df_col)
counter = len(df)
#generating for loop to create columns and give heading to them through df_col var.
for x in range(len(df_col)):
tree.column(x, width=100 )
tree.heading(x, text=df_col[x])
#generating for loop to print values of dataframe in treeview column.
for i in range(counter):
tree.insert('', 0, values=(df[df_col[x]]][i]))
It is not printing the columns and showing the KeyError:0.
Output Required:

Answer 1

The first argument of tree.column() should be the column name, which you assigned with:
tree["columns"]=(df_col)
The problem is that you have named the columns using a string, but you are attempting to access them using integers in:
for x in range(len(df_col)):
tree.column(x, width=100 )
tree.heading(x, text=df_col[x])
Above, you are attempting to access tree.columns(0), instead of tree.columns('Company'), hence the key error.
Try instead:
for x in range(len(df_col)):
tree.column(df_col[x], width=100)
tree.heading(df_col[x], text=df_col[x])
Note that df_col is an ndarray, not a dataframe, which is why df_col[x] works correctly (df[x] would give a key error). This is because df.columns.values returns an ndarray. As a side note, it may be a bit confusing to name an ndarray df_col.
There are also a few issues with your insert. The second argument should correspond to the index of the entry you wish to address. One solution is then to use a row index as the second argument, followed by a row label as text="rowLabel", followed by a list of values for the row:
tree.insert('', i, text=rowLabels[i], values=df.iloc[i,:].tolist())
Where rowLabels should be defined as whatever you want to use in the first column of the table. I would suggest using an index column from the spreadsheet here, if possible. It could be defined by:
rowLabels = df.iloc[:,indexColumn].tolist()
or:
rowLabels = df.index.tolist()
The latter is viable if df has named indices defined by a column during the spreadsheet import. In the former, indexColumn is an int referring to a column number in df that contains unique identifiers.
The option values=df.iloc[i,:].tolist() converts all columns of the ith row into a list, and, since we have passed an index value (the second argument) that gets larger, the call will insert a new row every loop (from the python tkinter docs entry on Treeview --> insert: "if index is greater than or equal to the current number of children, it is inserted at the end").
Finally, I am not sure if you did not post the end of your code, but, in order for the tree to show up, you will also need to use pack, grid, etc.
tree.pack()
or
tree.grid(row=0, column=0)
References:
https://docs.python.org/3/library/tkinter.ttk.html#tkinter.ttk.Treeview
This helpful example makes a few of the steps clear:
https://knowpapa.com/ttk-treeview/

Answer 2

As I was reading over your code. I noticed at the end line you have an extra bracket #:
df[df_col[x]]]
for i in range(counter):
tree.insert('', 0, values=(df[df_col[x]]][i]))
I would assume that would explain the KeyError.