Swift (Rules and variable declaration, initialization)

-
Well for the programming language for an ios is swift either we can use an objective c or with well I prefer swift as I am comfortable it .


In previous post we had talked about what is development in ios lets brief up first of all in android app we needed two files a java file and an xml file one for code and other business logic here also storyboard for U.i. design and ViewController.swift for business also its configuration file is info.plist.

Now coming back to swift there are some rules for it as follows
  • Semi colon(;) is not required end of statement.
  • Do not require variable declaration with specific Data type.
  • narrow or broad conversion that is casting must be done by the user.
  • To display text we have print("text") or println("text").
  • for a variable to print we have to write \(var) or for example \(a+b).
Rules for declaring variables ....
  • var var_name
with type annotation ....
  • var var_name:datatype
initializing  a variable.....
  • var var_name=value
with data type
  • var var_name:datatype=value
declaring constant we can write

let Constant_name=value








 

Comments

Post a Comment

Popular posts from this blog

State space search / blocks world problem by heuristic approach /TIC TAC TOE

-
A lot of AI is about SEARCH. The "state space" is the set of states of the problem we can get to by applying operators to a state of the problem to get a new state. A  state  contains  all of the information necessary to predict the effects of an action and to determine if it is a goal state. State-space searching assumes that the agent has perfect knowledge of the state space and can observe what state it is in (i.e., there is full observability); the agent has a set of actions that have known deterministic effects;some states are goal states, the agent wants to reach one of these goal states, and the agent can recognize a goal state. a solution is a sequence of actions that will get the agent from its current state to a goal state. Define the Problem as State Space Search Consider the problem of “Playing Chess” . to build a program that could play chess, we have to specify the starting position of the chess board, the rules that define legal moves. And the
Read more

Navigation in Vaadin.

-
Plain Vaadin applications do not have normal web page navigation as they usually run on a single page, as all Ajax applications do. Quite commonly, however, applications have different views between which the user should be able to navigate. The  Navigator  in Vaadin can be used for most cases of navigation. Views managed by the navigator automatically get a distinct URI fragment, which can be used to be able to bookmark the views and their states and to go back and forward in the browser history. The  Navigator  class manages a collection of  views  that implement the  View  interface. SO the class in which you are defining Navigation must implement with a  View  interface. addView() i s the method by which you can register Your View . You can add your view at any point ,Your View must have   name identifier and be added to a  View . Once registered, you can navigate to them with  navigateTo() . Navigator  manages navigation in a component container, which can be
Read more

Drag and drop items from one Grid to another

-
Following is a short example to drag and drop similar type of items from one Grid to another Grid in Vaadin 8 . package com . example . demo ; import java . util . ArrayList ; import java . util . List ; import java . util . Optional ; import com . vaadin . data . provider . ListDataProvider ; import com . vaadin . shared . ui . dnd . DropEffect ; import com . vaadin . shared . ui . dnd . EffectAllowed ; import com . vaadin . shared . ui . grid . DropMode ; import com . vaadin . ui . CustomComponent ; import com . vaadin . ui . Grid ; import com . vaadin . ui . HorizontalLayout ; import com . vaadin . ui . components . grid . GridDragSource ; import com . vaadin . ui . components . grid . GridDropTarget ; import com . vaadin . ui . renderers . ButtonRenderer ; public class DragAndDropFromGrid extends CustomComponent { /**       *      */ private static final long serialVersionUID = 1 L ; private HorizontalLayout hlytbase ;
Read more