firstcalc.py

#!/usr/bin/env python3
"""Example tab showing the common TraitsUI widgets wired to a live plot.

Each trait below maps to a control in :attr:`FirstCalc.view`; the
``_<name>_changed`` and ``_<name>_fired`` methods are the notifications Traits
calls automatically when a value changes or a button is pressed.
"""

import os
import random

import numpy as np
from traits.api import (
    Bool,
    Button,
    Directory,
    Enum,
    Float,
    HasTraits,
    Int,
    Range,
    Str,
)
from traitsui.api import Group, Item, View


class FirstCalc(HasTraits):
    """Demonstration panel driving the shared figure owned by the main window."""

    # Add Traits objects
    option = Bool(True)
    rangex = Range(1, 10, 5)
    yval = Float()
    listoptions = Enum("Option 1", "Option 2", "Option 3")
    stringopt = Str("Default string which can also be empty.")
    stringoptread = Str("Default string which can also be empty [read-only version].")
    masterpath = Directory()
    button1 = Button("Button 1 Name")
    floatval = Float()
    changedcount = Int()
    plotbutton = Button("Plot Me!")
    yintcept = Range(0.0, 5.0, 0.0)
    gradient = Range(0.0, 5.0, 1.0)

    # Construct the view

    view = View(
        Item(name="rangex", label="X-Value"),
        Item(name="yval", style="readonly", label="1/x", format_str="%.2e"),
        Item(name="listoptions", label="list of options"),
        Item(name="stringopt"),
        Item(name="stringoptread", style="readonly"),
        Item(name="masterpath", label="Directory"),
        Group(Item(name="button1", show_label=False)),
        Group(
            Item(name="option", label="Boolean Option"),
            enabled_when="floatval < 0.5",
            label="Enabled Area Upon Random Value < 0.5",
            show_border=True,
        ),
        Item(name="changedcount", style="readonly", label="Attempts"),
        Item(name="floatval", label="random generated"),
        Group(
            Item(name="gradient", label="gradient"),
            Item(name="yintcept", label="y-intercept"),
            Item(name="plotbutton", show_label=False),
            show_border=True,
            label="Plotting Area",
        ),
    )

    def __init__(self, main, **kwargs):
        super().__init__(**kwargs)
        self.main = main
        self.yval = 1.0 / self.rangex

    def _masterpath_default(self):
        return os.getcwd()

    def _line(self):
        """Return the (x, y) of the straight line described by the sliders."""
        x = np.arange(10)
        return x, self.gradient * x + self.yintcept

    def _replot(self):
        self.main.plot_xy(*self._line())

    # Both sliders describe the same line, so they share one handler.
    def _gradient_changed(self):
        self._replot()

    def _yintcept_changed(self):
        self._replot()

    def _plotbutton_fired(self):
        self._replot()

    def _rangex_changed(self):
        self.yval = 1.0 / self.rangex

    def _button1_fired(self):
        self.changedcount += 1
        self.floatval = random.random()

    def _floatval_changed(self):
        self.stringopt = "Hey, you changed the value!"