fix: we did not have a good chain of height: 100% divs

this did not enable users to add their own height: 100% elements
with scrollbars.

solara/autorouting.py

@@ -205,11 +205,12 @@ def get_args(f):
                 content = solara.Markdown(path.read_text(), unsafe_solara_execute=True)
 
             main = solara.Div(
+                classes=["solara-autorouter-content"],
                 children=[
                     solara.Title(route_current.label or "No title"),
                     content,
                     navigation,
-                ]
+                ],
             )
             main = wrap_in_layouts(main, layouts)
         else:
@@ -261,10 +262,11 @@ def get_args(f):
                     Page = getattr(modules[route_current.path], "app", None)
                     Page = getattr(modules[route_current.path], "page", Page)
             main = solara.Div(
+                classes=["solara-autorouter-content"],
                 children=[
                     title_element,
                     Page,
-                ]
+                ],
             )
             main = wrap_in_layouts(main, layouts)
         elif Page is not None:
@@ -276,10 +278,11 @@ def get_args(f):
             else:
                 page = solara.Error(f"{Page} is not a component or element, but {type(Page)}")
             main = solara.Div(
+                classes=["solara-autorouter-content"],
                 children=[
                     title_element,
                     page,
-                ]
+                ],
             )
             main = wrap_in_layouts(main, layouts)
         else:

solara/components/applayout.py

@@ -306,7 +306,12 @@ def set_path(index):
             with v.Row(no_gutters=False, class_="solara-content-main"):
                 v.Col(cols=12, children=children_content)
     else:
-        with v.Html(tag="div", style_="min-height: 100vh") as main:
+        # this limits the height of the app to the height of the screen
+        # and further down we use overflow: auto to add scrollbars to the main content
+        # the navigation drawer adds it own scrollbars
+        # NOTE: while developing this we added overflow: hidden, but this does not seem
+        # to be necessary anymore
+        with v.Html(tag="div", style_="height: 100vh") as main:
             with solara.HBox():
                 if use_drawer:
                     with v.NavigationDrawer(
@@ -340,8 +345,13 @@ def set_path(index):
                     if fullscreen:
                         solara.Button(icon_name="mdi-fullscreen-exit", on_click=lambda: set_fullscreen(False), icon=True, dark=False)
 
-            with v.Content(class_="solara-content-main"):
-                v.Col(cols=12, children=children_content)
+            with v.Content(class_="solara-content-main", style_="height: 100%;"):
+                # make sure the scrollbar does no go under the appbar by adding overflow: auto
+                # to a child of content, because content has padding-top: 64px (set by vuetify)
+                # the padding: 12px is needed for backward compatibility with the previously used
+                # v.Col which has this by default. If we do not use this, a solara.Column will
+                # use a margin: -12px which will make a horizontal scrollbar appear
+                solara.Div(style_="height: 100%; overflow: auto; padding: 12px;", children=children_content)
         if fullscreen:
             with v.Dialog(v_model=True, children=[], fullscreen=True, hide_overlay=True, persistent=True, no_click_animation=True) as dialog:
                 v.Sheet(class_="overflow-y-auto overflow-x-auto", children=[main])

solara/components/columns.py

@@ -74,7 +74,10 @@ def Page():
     style_flat = solara.util._flatten_style(style)
     with rv.Row(class_=class_, no_gutters=not gutters, dense=gutters_dense, style_=style_flat) as main:
         for child, width in zip(children, cycle(widths)):
-            with rv.Col(children=[child], style_=f"flex-grow: {width}; overflow: auto" if width != 0 else "flex-grow: 0;"):
+            # we add height: 100% because this will trigger a chain of height set if it is set on the parent
+            # via the style. If we do not set the height, it will have no effect. Furthermore, we only have
+            # a single child, so this cannot interfere with other siblings.
+            with rv.Col(children=[child], style_=f"height: 100%; flex-grow: {width}; overflow: auto" if width != 0 else "flex-grow: 0"):
                 pass
     return main
 

solara/server/assets/style.css

@@ -109,3 +109,7 @@ div.highlight {
 .solara-content-main {
     animation: solara-fade-in 0.5s ease;
 }
+
+.solara-autorouter-content {
+    height: 100%;
+}

solara/website/pages/apps/scrolling.py

@@ -0,0 +1,63 @@
+import solara
+
+github_url = solara.util.github_url(__file__)
+
+# list of nice soft colors
+colors = [
+    "#e6194b",
+    "#3cb44b",
+    "#ffe119",
+    "#4363d8",
+    "#f58231",
+    "#911eb4",
+]
+
+
+@solara.component
+def Page1():
+    with solara.Sidebar():
+        solara.Button(label="View source", icon_name="mdi-github-circle", attributes={"href": github_url, "target": "_blank"}, text=True, outlined=True)
+        solara.Markdown("The sidebar will get scrollbars automatically, independently of the main content.")
+        for i in range(10):
+            with solara.Card(f"Card {i}"):
+                solara.Info(f"Text {i}", color=colors[i % len(colors)])
+
+    solara.Markdown("The main content will get scrollbars automatically, independently of the sidebar.")
+    for i in range(10):
+        with solara.Card(f"Card {i}"):
+            solara.Info(f"Text {i}", color=colors[i % len(colors)])
+
+
+@solara.component
+def Page2():
+    # it is important we do not interrupt the height 100% chain
+    limit_content_height = solara.use_reactive(True)
+    # warning: if we add "margin": "10px" to the style, we will trigger
+    # scrollbars in the parent div, if you really need to add margins,
+    # you should correct for that in the height using "calc(100% - 20px)"
+    with solara.Column(style={"height": "100%"}):
+        with solara.Sidebar():
+            solara.Button(label="View source", icon_name="mdi-github-circle", attributes={"href": github_url, "target": "_blank"}, text=True, outlined=True)
+            solara.Markdown("Main content columns will scroll together, or independently if we limit height to 100%")
+            solara.Checkbox(label="Limit content height", value=limit_content_height)
+
+        # if we do not limit height to 100%, solara's AppLayout will add a scroll bar
+        # to the main content, which will be independent of the sidebar's scroll bar
+        # but both columns will scroll together
+        with solara.Columns([2, 4], style={"height": "100%"} if limit_content_height.value else {}):
+            with solara.Card("I have my own scroll bar"):
+                solara.Markdown("")
+                for i in range(10):
+                    with solara.Card(f"Card {i}"):
+                        solara.Info(f"Text {i}", color=colors[i % len(colors)])
+            with solara.Card("I also have my own scroll bar"):
+                solara.Markdown("")
+                for i in range(20):
+                    with solara.Card(f"Card {i}"):
+                        solara.Info(f"Text {i}", color=colors[i % len(colors)])
+
+
+routes = [
+    solara.Route(path="/", component=Page1, label="Scrolling"),
+    solara.Route(path="custom", component=Page2, label="Custom scrolling"),
+]

solara/website/pages/examples/fullscreen/scrolling.py

@@ -0,0 +1,3 @@
+redirect = "/apps/scrolling"
+
+Page = True