Chapter 5 Notes

Title: Dealing with Sizes

Summary

This chapter covers the consequences of different sized pixels and how we treat them.

Oh that screen drivers were built report screen size and to take unchanging units like inches and translate them based on the hardware. This would be a non-issue as we would always specify things in inches. BUT of course we would be discussing the exponential scaling curve that dictates how much you can scale down... (think dpi as a scaling factor). Then the curve might be $$Scale~Factor = B e^{-x}$$

Programming Concepts Summary

Concept

Page

Consequences of different sized pixels

87-89

Orientation changes are supported by default, but can be turned off.

95

Font Sizes

97

Programs

WhatSizePage

Page 91.

Concepts:

  1. Demonstrates the different sizes on different screens. Note: THIS PROGRAM DOES NOT USE DUIs! Instead it uses
  2. Demonstrates the event pattern by responding to size changes.
  3. Demonstrates how to use a timer to fire events.
  4. Dealing with Accessibility configuration changes.

Classes:

No new classes.

MetricalBoxViewPage

Page 96

Concepts:

  1. Demonstrates the differences in platforms when setting the same value for the DUI unit on different platforms using a BoxView.

No new classes.

FontSizesPage

Page 97

Concepts:

  1. Demonstrates the named font sizes compared to point font sizes.

No new classes.

EstimatedFontSizePage

Page 100

Concepts:

  1. Demonstrates sizing fonts based on view size.

No new classes.

FitToSizeClockPage

Page 103

Concepts:

  1. Lambda expressions
  2. Device.StartTimer demonstrated.

Classes:

  1. Device.StartTimer - Allows you to fire and event on a timer.

AccessibilityTestPage

Skip in class

Page 106

Concepts:

  1. What happens when an accessibility setting has changed? Larger Text.

No new classes.

EmpiricalFontSizePage

Page 109

Concepts:

  1. Divide and conquer method Log(n)... See notes on PDF.

ManagingAndProgrammingMobileApplications/Xamarin/Chapter 5 (last edited 2020-01-26 17:22:07 by scot)