Delete and Edit items in TreeView Tkinter

You are not deleting the whole tree you are just deleting all children from the root item, because you use delete for each item in your iteration. You can use a ifstatement to determine which item you want, or you can get the selected item with selected_item = tree.selection()[0] and delete it. With the .item()method you can full access to the item for modification. Example:

from Tkinter import Tk, Button
import ttk


root = Tk()

tree = ttk.Treeview(root)

tree["columns"]=("one","two")
tree.column("one", width=100 )
tree.column("two", width=100)
tree.heading("one", text="coulmn A")
tree.heading("two", text="column B")

tree.insert("" , 0,    text="Line 1", values=("1A","1b"))

id2 = tree.insert("", 1, "dir2", text="Dir 2")
tree.insert(id2, "end", "dir 2", text="sub dir 2", values=("2A","2B"))

##alternatively:
tree.insert("", 3, "dir3", text="Dir 3")
tree.insert("dir3", 3, text=" sub dir 3",values=("3A"," 3B"))

def edit():
    x = tree.get_children()
    for item in x: ## Changing all children from root item
        tree.item(item, text="blub", values=("foo", "bar"))

def delete():
    selected_item = tree.selection()[0] ## get selected item
    tree.delete(selected_item)

tree.pack()
button_del = Button(root, text="del", command=delete)
button_del.pack()
button_del = Button(root, text="edit", command=edit)
button_del.pack()

root.mainloop()