Merge pull request kivy#1238 from kivy/pagelayout

Create PageLayout layout

Author: akshayaurora

examples/widgets/pagelayout.py

@@ -0,0 +1,64 @@
+from kivy.base import runTouchApp
+from kivy.lang import Builder
+
+kv = '''
+PageLayout:
+    BoxLayout:
+        canvas:
+            Color:
+                rgba: 216/255., 195/255., 88/255., 1
+            Rectangle:
+                pos: self.pos
+                size: self.size
+
+        orientation: 'vertical'
+        Label:
+            size_hint_y: None
+            height: 1.5 * self.texture_size[1]
+            text: 'page 1'
+
+        Button:
+            text: 'test'
+            on_press: print "test"
+
+    BoxLayout:
+        orientation: 'vertical'
+        canvas:
+            Color:
+                rgba: 109/255., 8/255., 57/255., 1
+            Rectangle:
+                pos: self.pos
+                size: self.size
+
+        Label:
+            text: 'page 2'
+
+        AsyncImage:
+            source: 'http://kivy.org/logos/kivy-logo-black-64.png'
+
+    GridLayout:
+        canvas:
+            Color:
+                rgba: 37/255., 39/255., 30/255., 1
+            Rectangle:
+                pos: self.pos
+                size: self.size
+
+        cols: 2
+        Label:
+            text: 'page 3'
+        AsyncImage:
+            source: 'http://kivy.org/slides/kivyandroid-thumb.jpg'
+        Button:
+            text: 'test'
+            on_press: print "test last page"
+        AsyncImage:
+            source: 'http://kivy.org/slides/kivypictures-thumb.jpg'
+        Widget
+        AsyncImage:
+            source: 'http://kivy.org/slides/particlepanda-thumb.jpg'
+'''
+
+
+if __name__ == '__main__':
+    runTouchApp(Builder.load_string(kv))

kivy/factory_registers.py

@@ -92,6 +92,7 @@
 r('AnchorLayout', module='kivy.uix.anchorlayout')
 r('BoxLayout', module='kivy.uix.boxlayout')
 r('GridLayout', module='kivy.uix.gridlayout')
+r('PageLayout', module='kivy.uix.pagelayout')
 r('Accordion', module='kivy.uix.accordion')
 r('AccordionItem', module='kivy.uix.accordion')
 r('Button', module='kivy.uix.button')

kivy/uix/pagelayout.py

@@ -0,0 +1,182 @@
+"""
+PageLayout
+==========
+
+The :class:`PageLayout` class allow to create a simple multiple page
+layout, in a way that allows easy flipping of one page to another using
+borders.
+
+:class:`PageLayout` doesn't honor size_hint or pos_hint in any way currently.
+
+.. versionadded:: 1.8.1
+
+example::
+
+    PageLayout:
+        Button:
+            text: 'page1'
+
+        Button:
+            text: 'page2'
+
+        Button:
+            text: 'page3'
+"""
+
+__all__ = ('PageLayout', )
+
+from kivy.uix.layout import Layout
+from kivy.properties import NumericProperty
+from kivy.animation import Animation
+
+
+class PageLayout(Layout):
+    '''PageLayout class. See module documentation for more information
+    '''
+
+    '''Currently displayed page.
+
+    :data:`page` is a :class:`~kivy.properties.NumericProperty`, default to 0.
+    '''
+    page = NumericProperty(0)
+
+    '''Width of the border used around current page to display previous/next
+    page when needed.
+
+    :data:`border` is a :class:`~kivy.properties.NumericProperty`,
+    default to 0.
+    '''
+    border = NumericProperty('50dp')
+
+    '''Thresold to the swipe action triggering, as percentage of the widget
+    size.
+
+    :data:`swipe_threshold` is a :class:`~kivy.properties.NumericProperty`,
+    default to .5.
+    '''
+    swipe_threshold = NumericProperty(.5)
+
+    def __init__(self, **kwargs):
+        super(PageLayout, self).__init__(**kwargs)
+
+        self.bind(
+            border=self._trigger_layout,
+            page=self._trigger_layout,
+            parent=self._trigger_layout,
+            children=self._trigger_layout,
+            size=self._trigger_layout,
+            pos=self._trigger_layout)
+
+    def do_layout(self, *largs):
+        l_children = len(self.children)
+        for i, c in enumerate(reversed(self.children)):
+            if i < l_children:
+                width = self.width - self.border
+            else:
+                width = self.width - 2 * self.border
+
+            if i == 0:
+                x = self.x
+
+            elif i < self.page:
+                x = self.x
+
+            elif i == self.page:
+                x = self.x + self.border
+
+            elif i == self.page + 1:
+                x = self.right - self.border
+
+            else:
+                x = self.right
+
+            c.height = self.height
+            c.width = width
+
+            Animation(
+                x=x,
+                y=self.y,
+                d=.5, t='in_quad').start(c)
+
+    def on_touch_down(self, touch):
+        if self.y < touch.y < self.top:
+            if self.page > 0 and self.x < touch.x < (self.x + self.border):
+                touch.ud['page'] = 'previous'
+                touch.grab(self)
+                return True
+
+            elif (
+                self.page < len(self.children) - 1 and
+                self.right > touch.x > (self.right - self.border)
+            ):
+                touch.ud['page'] = 'next'
+                touch.grab(self)
+                return True
+
+        return self.children[-self.page - 1].on_touch_down(touch)
+
+    def on_touch_move(self, touch):
+        if touch.grab_current == self:
+            if touch.ud['page'] == 'previous':
+                self.children[-self.page - 1].x = max(min(
+                    self.x + self.border + (touch.x - touch.ox),
+                    self.right - self.border),
+                    self.x + self.border)
+
+                if self.page > 1:
+                    self.children[-self.page].x = min(
+                        self.x + self.border * (touch.sx - touch.osx),
+                        self.x + self.border)
+
+                if self.page < len(self.children) - 1:
+                    self.children[-self.page + 1].x = min(
+                        self.right - self.border * (1 - (touch.sx - touch.osx)),
+                        self.right)
+
+            elif touch.ud['page'] == 'next':
+                self.children[-self.page + 1].x = min(max(
+                    self.right - self.border + (touch.x - touch.ox),
+                    self.x + self.border),
+                    self.right - self.border)
+
+                if self.page >= 1:
+                    self.children[-self.page - 1].x = max(
+                        self.x + self.border * (1 - (touch.osx - touch.sx)),
+                        self.x)
+
+                if self.page < len(self.children) - 2:
+                    self.children[-self.page].x = max(
+                        self.right + self.border * (touch.sx - touch.osx),
+                        self.right - self.border)
+
+        return self.children[-self.page - 1].on_touch_move(touch)
+
+    def on_touch_up(self, touch):
+        if touch.grab_current == self:
+            if (
+                touch.ud['page'] == 'previous' and
+                abs(touch.sx - touch.osx) > self.swipe_threshold
+            ):
+                self.page -= 1
+            elif (
+                touch.ud['page'] == 'next' and
+                abs(touch.sx - touch.osx) > self.swipe_threshold
+            ):
+                self.page += 1
+            else:
+                self._trigger_layout()
+
+            touch.ungrab(self)
+        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)