""" PageLayout ========== .. image:: images/pagelayout.gif :align: right The :class:`PageLayout` class is used to create a simple multi-page layout, in a way that allows easy flipping from one page to another using borders. :class:`PageLayout` does not currently honor the :attr:`~kivy.uix.widget.Widget.size_hint`, :attr:`~kivy.uix.widget.Widget.size_hint_min`, :attr:`~kivy.uix.widget.Widget.size_hint_max`, or :attr:`~kivy.uix.widget.Widget.pos_hint` properties. .. versionadded:: 1.8.0 Example: .. code-block:: kv PageLayout: Button: text: 'page1' Button: text: 'page2' Button: text: 'page3' Transitions from one page to the next are made by swiping in from the border areas on the right or left hand side. If you wish to display multiple widgets in a page, we suggest you use a containing layout. Ideally, each page should consist of a single :mod:`~kivy.uix.layout` widget that contains the remaining widgets on that page. """ __all__ = ('PageLayout', ) from kivy.uix.layout import Layout from kivy.properties import NumericProperty, DictProperty from kivy.animation import Animation class PageLayout(Layout): '''PageLayout class. See module documentation for more information. ''' page = NumericProperty(0) '''The currently displayed page. :data:`page` is a :class:`~kivy.properties.NumericProperty` and defaults to 0. ''' border = NumericProperty('50dp') '''The width of the border around the current page used to display the previous/next page swipe areas when needed. :data:`border` is a :class:`~kivy.properties.NumericProperty` and defaults to 50dp. ''' swipe_threshold = NumericProperty(.5) '''The threshold used to trigger swipes as ratio of the widget size. :data:`swipe_threshold` is a :class:`~kivy.properties.NumericProperty` and defaults to .5. ''' anim_kwargs = DictProperty({'d': .5, 't': 'in_quad'}) '''The animation kwargs used to construct the animation :data:`anim_kwargs` is a :class:`~kivy.properties.DictProperty` and defaults to {'d': .5, 't': 'in_quad'}. .. versionadded:: 1.11.0 ''' def __init__(self, **kwargs): super(PageLayout, self).__init__(**kwargs) trigger = self._trigger_layout fbind = self.fbind fbind('border', trigger) fbind('page', trigger) fbind('parent', trigger) fbind('children', trigger) fbind('size', trigger) fbind('pos', trigger) def do_layout(self, *largs): l_children = len(self.children) - 1 h = self.height x_parent, y_parent = self.pos p = self.page border = self.border half_border = border / 2. right = self.right width = self.width - border for i, c in enumerate(reversed(self.children)): if i < p: x = x_parent elif i == p: if not p: # it's first page x = x_parent elif p != l_children: # not first, but there are post pages x = x_parent + half_border else: # not first and there are no post pages x = x_parent + border elif i == p + 1: if not p: # second page - no left margin x = right - border else: # there's already a left margin x = right - half_border else: x = right c.height = h c.width = width Animation( x=x, y=y_parent, **self.anim_kwargs).start(c) def on_touch_down(self, touch): if ( self.disabled or not self.collide_point(*touch.pos) or not self.children ): return page = self.children[-self.page - 1] if self.x <= touch.x < page.x: touch.ud['page'] = 'previous' touch.grab(self) return True elif page.right <= touch.x < self.right: touch.ud['page'] = 'next' touch.grab(self) return True return page.on_touch_down(touch) def on_touch_move(self, touch): if touch.grab_current != self: return p = self.page border = self.border half_border = border / 2. page = self.children[-p - 1] if touch.ud['page'] == 'previous': # move next page up to right edge if p < len(self.children) - 1: self.children[-p - 2].x = min( self.right - self.border * (1 - (touch.sx - touch.osx)), self.right) # move current page until edge hits the right border if p >= 1: b_right = half_border if p > 1 else border b_left = half_border if p < len(self.children) - 1 else border self.children[-p - 1].x = max(min( self.x + b_left + (touch.x - touch.ox), self.right - b_right), self.x + b_left) # move previous page left edge up to left border if p > 1: self.children[-p].x = min( self.x + half_border * (touch.sx - touch.osx), self.x + half_border) elif touch.ud['page'] == 'next': # move current page up to left edge if p >= 1: self.children[-p - 1].x = max( self.x + half_border * (1 - (touch.osx - touch.sx)), self.x) # move next page until its edge hit the left border if p < len(self.children) - 1: b_right = half_border if p >= 1 else border b_left = half_border if p < len(self.children) - 2 else border self.children[-p - 2].x = min(max( self.right - b_right + (touch.x - touch.ox), self.x + b_left), self.right - b_right) # move second next page up to right border if p < len(self.children) - 2: self.children[-p - 3].x = max( self.right + half_border * (touch.sx - touch.osx), self.right - half_border) return page.on_touch_move(touch) def on_touch_up(self, touch): if touch.grab_current == self: if ( touch.ud['page'] == 'previous' and abs(touch.x - touch.ox) / self.width > self.swipe_threshold ): self.page -= 1 elif ( touch.ud['page'] == 'next' and abs(touch.x - touch.ox) / self.width > self.swipe_threshold ): self.page += 1 else: self._trigger_layout() touch.ungrab(self) if len(self.children) > 1: return self.children[-self.page + 1].on_touch_up(touch) if __name__ == '__main__': from kivy.base import runTouchApp from kivy.uix.button import Button pl = PageLayout() for i in range(1, 4): b = Button(text='page%s' % i) pl.add_widget(b) runTouchApp(pl)