sojinkim / calculator Goto Github PK

Yet

and .gitignore is missing

and it is annoying a lot
will change the outlet event type to "touch down" .. someday..

.. getting super lazy

also, will investigate little bit more gradient layer on button ... sometime soon..

enter digit + sign + enter more digits
will revert sign

damn. why every simple change introduces bugs -_-

unsupported configuration
unknown pattern color for the highlighted title color attribute

xcode.. not cute anymore

반성

• design rather driven by ui, than by function ..
• state pattern not really open to change, unless each states / state transitions carefully defined in the first place. didn't foresee memory function would change the state, nor some inputs would cause multiple state transitions. the reason i call it multiple state transitions is that one state can not access another state property, so it had to pass through.. means that, probably i should have defined all the properties in brain, so that every state can modify the values. omg. yes maybe, states work on behalf of the brain. may not make much sense to hide/abstract data from each other.. one supporting evidence of this is after exiting a state, that state's property is still alive, e.g., left operand is valid and accessed until the calculation is performed.
• it would be better that each state more focuses on its own error handling, and examining exit criteria, rather than trying to pass verified data to other state. in other words, mind your own business. unless, it becomes untraceable as more reqs are revealed.
• if something happens in a state which was not supposed to happen, do not workaround by if-else's .. time to new start -_-

core properties..

1. left operand
2. operator
3. right operand
4. result
5. memory
6. user input string (number)
7. display string

user input string becomes either left operand, right operand, or memory
-> should convert and store before leaving the operand state

result becomes left operand
-> wait, do not push the value to left operand, until exiting the operand state.

memory becomes left operand, or right operand
-> again, wait until user finally decide to accept that value by exiting the operand state.

display string : ui dependent. coming from user input, memory or result.
-> let controller compose the presentation using 1-6

😿

Press
12.3
M+
Mr
0.345

-> Displays 12.30.345

Because isDecimalPressed == No

Simplest fix might be scan for dot in mr value, and turn the decimal flag on.
But as in ios, i will prohibit altering mr value on the display. Any attemp to entering digit will discard the mr value.. sign change will be allowed.

-_-

on iphone cal.
these buttons have toggle state

decimal - not implemented
sign - signed number, followed by digit input

need to redesign the way getting user input

state transition and exceptional case handling became so dirty, requires extensive manual tests on every code change, so now it makes perfect sense to generate unit tests .. dammit

I was curious if there was "C++ friend" equivalent in Objective C. Stack overflow says Category is one way to mimic it.

So, let's try it.