from tkinter import *
from time import time, localtime, strftime


class ToolTip( Toplevel ):
    """
    Provides a ToolTip widget for Tkinter.
    To apply a ToolTip to any Tkinter widget, simply pass the widget to the
    ToolTip constructor
    """ 
    def __init__( self, wdgt, msg=None, msgFunc=None, delay=1, follow=True ):
        """
        Initialize the ToolTip
        
        Arguments:
          wdgt: The widget this ToolTip is assigned to
          msg:  A static string message assigned to the ToolTip
          msgFunc: A function that retrieves a string to use as the ToolTip text
          delay:   The delay in seconds before the ToolTip appears(may be float)
          follow:  If True, the ToolTip follows motion, otherwise hides
        """
        self.wdgt = wdgt
        self.parent = self.wdgt.master                                          # The parent of the ToolTip is the parent of the ToolTips widget
        Toplevel.__init__( self, self.parent, bg='black', padx=1, pady=1 )      # Initalise the Toplevel
        self.withdraw()                                                         # Hide initially
        self.overrideredirect( True )                                           # The ToolTip Toplevel should have no frame or title bar
        
        self.msgVar = StringVar()                                               # The msgVar will contain the text displayed by the ToolTip        
        if msg == None:                                                         
            self.msgVar.set( 'No message provided' )
        else:
            self.msgVar.set( msg )
        self.msgFunc = msgFunc
        self.delay = delay
        self.follow = follow
        self.visible = 0
        self.lastMotion = 0
        Message( self, textvariable=self.msgVar, bg='#FFFFDD',
                 aspect=1000 ).grid()                                           # The test of the ToolTip is displayed in a Message widget
        self.wdgt.bind( '<Enter>', self.spawn, '+' )                            # Add bindings to the widget.  This will NOT override bindings that the widget already has
        self.wdgt.bind( '<Leave>', self.hide, '+' )
        self.wdgt.bind( '<Motion>', self.move, '+' )
        
    def spawn( self, event=None ):
        """
        Spawn the ToolTip.  This simply makes the ToolTip eligible for display.
        Usually this is caused by entering the widget
        
        Arguments:
          event: The event that called this funciton
        """
        self.visible = 1
        self.after( int( self.delay * 1000 ), self.show )                       # The after function takes a time argument in miliseconds
        
    def show( self ):
        """
        Displays the ToolTip if the time delay has been long enough
        """
        if self.visible == 1 and time() - self.lastMotion > self.delay:
            self.visible = 2
        if self.visible == 2:
            self.deiconify()
            
    def move( self, event ):
        """
        Processes motion within the widget.
        
        Arguments:
          event: The event that called this function
        """
        self.lastMotion = time()
        if self.follow == False:                                                # If the follow flag is not set, motion within the widget will make the ToolTip dissapear
            self.withdraw()
            self.visible = 1
        self.geometry( '+%i+%i' % ( event.x_root+10, event.y_root+10 ) )        # Offset the ToolTip 10x10 pixes southwest of the pointer
        try:
            self.msgVar.set( self.msgFunc() )                                   # Try to call the message function.  Will not change the message if the message function is None or the message function fails
        except:
            pass
        self.after( int( self.delay * 1000 ), self.show )
            
    def hide( self, event=None ):
        """
        Hides the ToolTip.  Usually this is caused by leaving the widget
        
        Arguments:
          event: The event that called this function
        """
        self.visible = 0
        self.withdraw()


def xrange2d( n,m ):
    """
    Returns a generator of values in a 2d range
    
    Arguments:
      n: The number of rows in the 2d range
      m: The number of columns in the 2d range
    Returns:
      A generator of values in a 2d range
    """
    return ( (i,j) for i in xrange(n) for j in xrange(m) )


def range2d( n,m ):
    """
    Returns a list of values in a 2d range
    
    Arguments:
      n: The number of rows in the 2d range
      m: The number of columns in the 2d range
    Returns:
      A list of values in a 2d range
    """
    return [(i,j) for i in range(n) for j in range(m) ]


def print_time():
    """
    Prints the current time in the following format:
    HH:MM:SS.00
    """
    t = time()
    timeString = 'time='
    timeString += strftime( '%H:%M:', localtime(t) )
    timeString += '%.2f' % ( t%60, )
    return timeString
    
def main():
    root = Tk()
    btnList = []
    for (i,j) in range2d( 6, 4 ):
        text = 'delay=%i\n' % i
        delay = i
        if j >= 2:
            follow=True
            text += '+follow\n'
        else:
            follow = False
            text += '-follow\n'
        if j % 2 == 0:
            msg = None
            msgFunc = print_time
            text += 'Message Function'
        else:
            msg = 'Button at %s' % str( (i,j) )
            msgFunc = None
            text += 'Static Message'
        btnList.append( Button( root, text=text ) )
        ToolTip( btnList[-1], msg=msg, msgFunc=msgFunc, follow=follow, delay=delay)
        btnList[-1].grid( row=i, column=j, sticky=N+S+E+W )
    root.mainloop()
    
if __name__ == '__main__':
    main()