Scroll View

New in version 1.0.4.

The ScrollView widget provides a scrollable/pannable viewport that is clipped at the scrollview’s bounding box.

Scrolling Behavior

ScrollView accepts only one child, and applies a viewport/window to it according to the scroll_x and scroll_y properties. Touches are analyzed to determine if the user wants to scroll or control the child in some other manner - you cannot do both at the same time. To determine if interaction is a scrolling gesture, these properties are used:

If a touch travels scroll_distance pixels within the scroll_timeout period, it is recognized as a scrolling gesture and translatation (scroll/pan) will begin. If the timeout occurs, the touch down event is dispatched to the child instead (no translation).

New in version 1.1.1.

Limiting to X or Y Axis

By default, ScrollView allows scrolling in both the X and Y axes. You can explicitly disable scrolling on an axis by setting ScrollView.do_scroll_x or ScrollView.do_scroll_y to False.

Managing the Content Size

ScrollView manages the position of the child content, not the size. You must carefully specify the size_hint of your content to get the desired scroll/pan effect.

By default, size_hint is (1, 1), so the content size will fit your ScrollView exactly (you will have nothing to scroll). You must deactivate at least one of the size_hint instructions (x or y) of the child to enable scrolling.

To scroll a GridLayout on Y-axis/vertically, set the child’s width identical to that of the ScrollView (size_hint_x=1, default), and set the size_hint_y property to None:

layout = GridLayout(cols=1, spacing=10, size_hint_y=None)
#Make sure the height is such that there is something to scroll.
layout.bind(minimum_height=layout.setter('height'))
for i in range(30):
    btn = Button(text=str(i), size_hint_y=None, height=40)
    layout.add_widget(btn)
root = ScrollView(size_hint=(None, None), size=(400, 400))
root.add_widget(layout)

Controlling Timeout, Distance and Trigger

New in version 1.0.8.

In your configuration file, you can some default values for this widget:

[widgets]
scroll_timeout = 250
scroll_distance = 20
scroll_friction = 1.

If you want to reduce the default timeout, you can set:

[widgets]
scroll_timeout = 150
class kivy.uix.scrollview.ScrollView(**kwargs)

Bases: kivy.uix.stencilview.StencilView

ScrollView class. See module documentation for more information.

auto_scroll

Automatic scrolling is the movement activated after a swipe. When you release a touch, it will start to move the list, according to the lastest touch movement. If you don’t want that behavior, just set the auto_scroll to False.

auto_scroll is a BooleanProperty, default to True

bar_color

Color of horizontal / vertical scroll bar, in RGBA format.

New in version 1.2.0.

bar_color is a ListProperty, default to [.7, .7, .7, .9].

bar_margin

Margin between the bottom / right side of the scrollview when drawing the horizontal / vertical scroll bar.

New in version 1.2.0.

bar_margin is a NumericProperty, default to 0

bar_width

Width of the horizontal / vertical scroll bar. The width is interpreted as a height for the horizontal bar.

New in version 1.2.0.

bar_width is a NumericProperty, default to 2

convert_distance_to_scroll(dx, dy)

Convert a distance in pixels to a scroll distance, depending on the content size and the scrollview size.

The result will be a tuple of scroll distance that can be added to scroll_x and scroll_y

do_scroll

Allow scroll on X or Y axis.

do_scroll is a AliasProperty of (do_scroll_x + do_scroll_y)

do_scroll_x

Allow scroll on X axis.

do_scroll_x is a BooleanProperty, default to True.

do_scroll_y

Allow scroll on Y axis.

do_scroll_y is a BooleanProperty, default to True.

hbar

Return a tuple of (position, size) of the horizontal scrolling bar.

New in version 1.2.0.

The position and size are normalized between 0-1, and represent a percentage of the current scrollview height. This property is used internally for drawing the little horizontal bar when you’re scrolling.

vbar is a AliasProperty, readonly.

scroll_distance

Distance to move before scrolling the ScrollView, in pixels. As soon as the distance has been traveled, the ScrollView will start to scroll, and no touch event will go to children. It is advisable that you base this value on the dpi of your target device’s screen.

scroll_distance is a NumericProperty, default to 20 (pixels), according to the default value in user configuration.

scroll_friction

Friction is a factor for reducing the scrolling when the list is not moved by a touch. When you do a swipe, the movement speed is calculated, and is used to move the list automatically when touch up happens. The speed is reducing from this equation:

2 ^ (t * f)
# t is the time from the touch up
# f is the friction

By default, the friction factor is 1. It will reduce the speed by a factor of 2 each second. If you set the friction to 0, the list speed will never stop. If you set to a bigger value, the list movement will stop faster.

scroll_friction is a NumericProperty, default to 1, according to the default value in user configuration.

scroll_moves

The speed of automatic scrolling is based on previous touch moves. This is to prevent accidental slowing down by the user at the end of the swipe to slow down the automatic scrolling. The moves property specifies the amount of previous scrollmoves that should be taken into consideration when calculating the automatic scrolling speed.

scroll_moves is a NumericProperty, default to 5.

New in version 1.5.0.

scroll_stoptime

Time after which user input not moving will disable autoscroll for that move. If the user has not moved within the stoptime, autoscroll will not start. This is to prevent autoscroll to trigger while the user has slowed down on purpose to prevent this.

scroll_stoptime is a NumericProperty, default to 300 (milliseconds)

New in version 1.5.0.

scroll_timeout

Timeout allowed to trigger the scroll_distance, in milliseconds. If the user has not moved scroll_distance within the timeout, the scrolling will be disabled, and the touch event will go to the children.

scroll_timeout is a NumericProperty, default to 55 (milliseconds), according to the default value in user configuration.

Changed in version 1.5.0: Default value changed from 250 to 55.

scroll_x

X scrolling value, between 0 and 1. If 0, the content’s left side will touch the left side of the ScrollView. If 1, the content’s right side will touch the right side.

This property is controled by ScrollView only if do_scroll_x is True.

scroll_x is a NumericProperty, default to 0.

scroll_y

Y scrolling value, between 0 and 1. If 0, the content’s bottom side will touch the bottom side of the ScrollView. If 1, the content’s top side will touch the top side.

This property is controled by ScrollView only if do_scroll_y is True.

scroll_y is a NumericProperty, default to 1.

update_from_scroll(*largs)

Force the reposition of the content, according to current value of scroll_x and scroll_y.

This method is automatically called when one of the scroll_x, scroll_y, pos or size properties change, or if the size of the content changes.

vbar

Return a tuple of (position, size) of the vertical scrolling bar.

New in version 1.2.0.

The position and size are normalized between 0-1, and represent a percentage of the current scrollview height. This property is used internally for drawing the little vertical bar when you’re scrolling.

vbar is a AliasProperty, readonly.