New vertical layout demo program

DemoPrograms/Demo_Layout_Vertical.py

@@ -0,0 +1,75 @@
+import PySimpleGUI as sg
+
+"""
+    Demo of using the vertical layout parameters and layout helper functions.
+    Three methods of vertical alignment are shown:
+    1. Using Column element to align a single element
+    2. Using vtop layout helper function to align a single element
+    3. Using vtop layout helper function to align an entire row
+
+    There is also a funciton provided that will convert an entire layout into 
+    a top aligned layout.
+    
+    Copyright 2020 PySimpleGUI.org    
+"""
+
+def top_align_layout(layout):
+    """
+    Given a layout, return a layout with all rows vertically adjusted to the top
+
+    :param layout: List[List[sg.Element]] The layout to justify
+    :return: List[List[sg.Element]]  The new layout that is all top justified
+    """
+    new_layout = []
+    for row in layout:
+        new_layout.append(sg.vtop(row))
+    return new_layout
+
+
+def main():
+    # -------------------- Example 1 - No alignment --------------------
+    layout = [ [sg.T('This layout uses no vertical alignment. The default is "center"')],
+               [sg.Text('On row 1'), sg.Listbox(list(range(10)), size=(5,4)), sg.Text('On row 1')],
+               [sg.Button('OK')]  ]
+
+    sg.Window('Window Title', layout).read(close=True)
+
+    # -------------------- Example 2 - Top aligned Text element using Column --------------------
+    layout = [ [sg.T('This uses a Column Element to align 1 element')],
+               [sg.Col([[sg.Text('On row 1')]], vertical_alignment='top', pad=(0,0)), sg.Listbox(list(range(10)), size=(5,4)), sg.Text('On row 1')],
+               [sg.Button('OK')]  ]
+
+    sg.Window('Window Title', layout).read(close=True)
+
+
+    # -------------------- Example 3 - Top aligned Text element using Column --------------------
+    layout = [ [sg.T('This layout uses the "vtop" layout helper function on 1 element')],
+               [sg.vtop(sg.Text('On row 1')), sg.Listbox(list(range(10)), size=(5,4)), sg.Text('On row 1')],
+               [sg.Button('OK')]  ]
+
+    sg.Window('Window Title', layout).read(close=True)
+
+    # -------------------- Example 4 - Top align an entire row --------------------
+    # Note that the vtop function takes a row as input and returns a row.  DO NOT place [ ] around vtop
+    # because it is a row already.
+    layout = [ [sg.T('This layout uses the "vtop" layout helper function on 1 row')],
+               sg.vtop([sg.Text('On row 1'), sg.Listbox(list(range(10)), size=(5,4)), sg.Text('On row 1')]),
+               [sg.Button('OK')]  ]
+
+    sg.Window('Window Title', layout).read(close=True)
+
+
+    # -------------------- Example 5 - Use function to align all rows in layout --------------------
+    layout = [ [sg.T('This layout has all rows top aligned using function')],
+               [sg.Text('On row 1'), sg.Listbox(list(range(10)), size=(5,4)), sg.Text('On row 1')],
+               [sg.Text('On row 2'), sg.Listbox(list(range(10)), size=(5,4)), sg.Text('On row 2')],
+               [sg.Button('OK')]  ]
+
+    layout = top_align_layout(layout)       # pass in a layout, get a loyout back
+
+    sg.Window('Window Title', layout).read(close=True)
+
+
+
+if __name__ == '__main__':
+    main()