无法正确显示 Tkinter Treeview 中的图像

Question

I want my method to pull images from a sqlite database and display them as an image for the particular row in a Treeview. Unfortunately, it's only displaying the image in the last row inserted. I defined a singular image outside of the loop and it displayed an image on each row as I wanted. This leads me to believe that when I dynamically define the image in the loop, the images are getting garbage collected. In order for me to pull images from the database and place them in the Treeview, I can't have a single image definition outside the loop, but I'm not sure how to prevent garbage collection otherwise.

Note: db.getdata() is a function from another file that returns.fetchall() from the database.

 def update_records(self):

        records = self.dbTree.get_children()

        for element in records:
            self.dbTree.delete(element)

        db_rows = db.get_data()

        #img = PhotoImage(file = 'earth.gif').subsample(30, 30)

        for row in db_rows:
            img = tk.PhotoImage(data=row[5]).subsample(20, 20)
            self.dbTree.insert('', 0, text = row[0], values = (row[1], row[2], row[3], row[4]), image 
                              = img)           
            self.dbTree.image = img

Image of window

Answer 1

Since you used same attribute self.dbTree.image to save the reference of images, only the last image will be kept and the others are garbage collected.

Use a dictionary to store the images:

self.dbTree.images = {}
for row in db_rows:
    img = tk.PhotoImage(data=row[5]).subsample(20, 20)
    self.dbTree.insert('', 0, text=row[0], values=(row[1], row[2], row[3], row[4]), image=img)           
    self.dbTree.images[row[0]] = img