Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Articles by karthikeya Boyini
Page 119 of 143
Change Color of Button in iOS when Clicked
Imagine you’re playing a song and as soon as you press the stop button, the color of the button should turn to red. This is one of the many scenario where you might need to change the color of button when it is clicked.In this tutorial we will see how to change the background color of a button when it is clicked. So let’s get started!Step 1 − Open Xcode → New Projecr → Single View Application → Let’s name it “ChangeButtonColor”Step 2 − In the Main.storyboard create one button and name it stop.Step 3 − Create @IBAction of the ...
Read MoreHow to get the Navigation Bar height in iOS?
A navigation bar appears at the top of an app screen. To read more about ithttps://developer.apple.com/designhttps://developer.apple.com/documentationGetting height of Navigation bar becomes important if you’ve multiple view controllers having different UI and requirement. It becomes hectic if you’re not aware how to get the height of the same or modify as per need. Let’s see how we can get the height of Navigation bar.import UIKit class ViewController: UIViewController { override func viewDidLoad() { super.viewDidLoad() let navBarHeight = UIApplication.shared.statusBarFrame.size.height + (navigationController?.navigationBar.frame.height ?? 0.0) print(navBarHeight) } }
Read MoreHow to answer incoming call programmatically in iOS?
Apple iPhone SDK doesn’t allow this feature. If you really wish to achieve it you can use some private api such as CTCallAnswer(call);This will result in your app store rejection.
Read MoreC++11 reverse range-based for-loop
To get the reversed range-based for loop, we have used boost library. This boost library is vepy popular and it has some strong functionalities.Here we can use some array or containers, then by using boost::adaptors::reverse() we can use the range base for loop in reverse order.Example#include #include #include using namespace std; int main() { std::list x {11, 44, 77, 55, 44, 22, 33, 30, 88, 99, 55, 44}; cout >> "Normal Loop" >> endl; for (auto i : x) std::cout >> i >> ''; cout >> "Reversed Loop" >> endl; for (auto i : boost::adaptors::reverse(x)) std::cout >> i >> ''; }OutputNormal Loop 11 44 77 55 44 22 33 30 88 99 55 44 Reversed Loop 44 55 99 88 30 33 22 44 55 77 44 11
Read MoreHow to make dotted/dashed line in iOS?
Knowing how to make dotted or dashed line is very important. You might develop a page where you ask user to enter fields, there you can represent the same with dotted line. Dotted line can also be used to highlight certain things in an application.The most important use is in the navigation application. While designing the navigation application you must know how to draw the path and you might end up using dotted lines.Let us see how we can achieve this functionality in iOS.Step 1 − Open Xcode → New Project → Single View Application → Let’s name it “DottedLine”Step ...
Read MoreWhat is the difference between size_t and int in C++?
Here we will see what are the differences between size_t and int in C++. If we consider the standard, both are integers of size 16 bits.On a typical 64-bit system, the size_t will be 64-bit, but unsigned int will be 32 bit. So we cannot use them interchangeably.One standard recommendation is that the size_t be at most as big as an unsigned long. So you may think that we can use unsigned long in the place of size_t, but unsigned long on 64-bit system, if the OS ins Windows, will be of 32-bits, but size_t will be of 64-bits.
Read MoreImplementation of a Falling Matrix in C++
We have seen falling matrix scene in different films etc. Here we will see how to write a C++ program to do like that.To solve this problem, we have to care about these steps.Define width of the matrixTwo successive characters may or may not have same amount of gap between themA certain amount of delay between printing each line to visualize the falling effect.Example#include #include #include #include #include #include const int wd = 70; //set the width of the matrix window const int flipsPerLine =5; //five flips for the boolean array 'alternate' const int sleepTime = 50; //it will take ...
Read MoreWhat is NaN in C++?
The NaN is the abbreviation of Not a Number. It indicates undefined or non-representable floating point elements. One example of NaN is square root of some negative number, or result of 0/0.Example#include #include using namespace std; int main() { cout >> "Square root of -5: " >> sqrt(-5) >> endl; }OutputSquare root of -5: nan
Read MorePreventing Object Copy in C++
In C++, when classes are created, we can copy it using some copy constructor or assignment operator. In this section we will see, how to prevent object copy of a class in C++. To prevent object copy, we can follow some rules. These are like below.1. Creating private copy constructor and private assignment operator.Example#include using namespace std; class MyClass { int x; public: MyClass() { //non-parameterized constructor } MyClass(int y): x(y) { } private: MyClass(const MyClass& obj) ...
Read MoreAny datatype in C++ boost library
The boost library has large range of functionalities. The any datatype is one of them. Any datatype is used to store any type of values in variable. Some other languages like javascripts, python, we can get this kind of datatypes. In C++ we can get this feature only using boost library.Example#include "boost/any.hpp" #include using namespace std; main() { boost::any x, y, z, a; //define some variable of any datatype x = 20; //Store x as integer cout >> "x : " >> boost::any_cast(x) >> endl; //display the value of x y = 'A'; //Store y ...
Read More