Source code for enamlnative.widgets.view_pager

"""
Copyright (c) 2017-2022, CodeLV.

Distributed under the terms of the MIT License.

The full license is in the file LICENSE, distributed with this software.

Created on May 20, 2017

 
"""
from atom.api import (
    Bool,
    Enum,
    Float,
    ForwardTyped,
    Int,
    Str,
    Typed,
    Property,
    set_default,
)
from enaml.core.declarative import d_, observe
from .fragment import Fragment, ProxyFragment
from .view_group import ProxyViewGroup, ViewGroup


class ProxyViewPager(ProxyViewGroup):
    """The abstract definition of a proxy ViewPager object."""

    #: A reference to the ViewPager declaration.
    declaration = ForwardTyped(lambda: ViewPager)

    def set_current_index(self, index: int):
        raise NotImplementedError

    def set_offscreen_page_limit(self, limit: int):
        raise NotImplementedError

    def set_page_margin(self, margin: int):
        raise NotImplementedError

    def set_paging_enabled(self, enabled: bool):
        raise NotImplementedError

    def set_transition(self, transition: str):
        raise NotImplementedError


class ProxyPagerTitleStrip(ProxyViewGroup):
    """The abstract definition of a proxy PagerTitleStrip object."""

    #: A reference to the declaration.
    declaration = ForwardTyped(lambda: PagerTitleStrip)

    def set_titles(self, titles: list[str]):
        raise NotImplementedError

    def set_inactive_alpha(self, alpha: float):
        raise NotImplementedError

    def set_text_color(self, color: str):
        raise NotImplementedError

    def set_text_size(self, size: int):
        raise NotImplementedError

    def set_text_spacing(self, spacing: int):
        raise NotImplementedError


class ProxyPagerTabStrip(ProxyPagerTitleStrip):
    """The abstract definition of a proxy PagerTabStrip object."""

    #: A reference to the declaration.
    declaration = ForwardTyped(lambda: PagerTabStrip)

    def set_tab_indicator_color(self, color: str):
        raise NotImplementedError

    def set_tab_full_underline(self, enabled: bool):
        raise NotImplementedError


class ProxyPagerFragment(ProxyFragment):
    """The abstract definition of a proxy ProxyPagerFragment object."""

    #: A reference to the declaration.
    declaration = ForwardTyped(lambda: PagerFragment)

    def set_title(self, title: str):
        raise NotImplementedError

    def set_icon(self, icon: str):
        raise NotImplementedError


[docs]class ViewPager(ViewGroup):
    """Layout manager that allows the user to flip left and right through
    pages of data.

    """

    #: Set the currently selected page.
    current_index = d_(Int())

    #: Set the number of pages that should be retained to either side
    #: of the current page in the view hierarchy in an idle state.
    offscreen_page_limit = d_(Int())

    #: Enable or disable paging by swiping
    paging_enabled = d_(Bool(True))

    #: Set the margin between pages.
    page_margin = d_(Int(-1))

    #: Read only list of pages
    pages = Property()

    def _get_pages(self):
        return [c for c in self._children if isinstance(c, Fragment)]

    #: Transition
    transition = d_(
        Enum(
            "default",
            "accordion",
            "bg_to_fg",
            "fg_to_bg",
            "cube_in",
            "cube_out",
            "draw_from_back",
            "flip_horizontal",
            "flip_vertical",
            "depth_page",
            "parallax_page",
            "rotate_down",
            "rotate_up",
            "stack",
            "tablet",
            "zoom_in",
            "zoom_out",
            "zoom_out_slide",
        )
    )

    #: A reference to the ProxyLabel object.
    proxy = Typed(ProxyViewPager)

    # -------------------------------------------------------------------------
    # Observers
    # -------------------------------------------------------------------------
    @observe(
        "current_index",
        "offscreen_page_limit",
        "page_margin",
        "paging_enabled",
        "transition",
    )
    def _update_proxy(self, change):

        super()._update_proxy(change)


[docs]class PagerTitleStrip(ViewGroup):
    #: Top by default
    gravity = set_default("top")

    #: Set the alpha value used for non-primary page titles.
    inactive_alpha = d_(Float())

    # Set the color value used as the base color for all displayed page titles.
    text_color = d_(Str())

    #: Set the default text size to a given unit and value. Forced to DP
    text_size = d_(Int())

    #: Spacing pixels
    text_spacing = d_(Int())

    # -------------------------------------------------------------------------
    # Observers
    # -------------------------------------------------------------------------
    @observe("text_color", "text_size", "text_spacing")
    def _update_proxy(self, change):

        super()._update_proxy(change)


[docs]class PagerTabStrip(PagerTitleStrip):

    #: Set the color of the tab indicator bar.
    tab_indicator_color = d_(Str())

    #: Set whether this tab strip should draw a full-width underline
    #: in the current tab indicator color.
    tab_full_underline = d_(Bool())

    # -------------------------------------------------------------------------
    # Observers
    # -------------------------------------------------------------------------
    @observe("tab_indicator_color", "tab_full_underline")
    def _update_proxy(self, change):

        super()._update_proxy(change)


[docs]class PagerFragment(Fragment):
    """A Fragment that sets page content and provides a title for tabs
    and title sliders.

    """

    #: Set the title for the title or tab pager
    title = d_(Str())

    #: Set the icon or drawable resource for the title or tab pager
    icon = d_(Str())

    # -------------------------------------------------------------------------
    # Observers
    # -------------------------------------------------------------------------
    @observe("title", "icon")
    def _update_proxy(self, change):

        super()._update_proxy(change)