xcode 8 mac user interface builder tutorial

Once you finish this, you don’t have to type the same piece of code ever. The XCode will open a popup, in which you have to enter the title, description, scope, shortcut. To create your custom snippet, prepare the piece of code you want, and drag it to the utilities panel. You can see that in the bottom of the Utilities panel. Snippets are the small piece of code saved with the XCode, which can be used whenever needed without having to type the same piece of code again and again.īy default the XCode have many code snippets. But in the XCode, we can create our own code completion shortcuts with the help of snippets.

One of the most advanced feature of XCode is Code Completion, which is available now with most of the SDKs.īut the sad part is, many SDKs provide the code completion only for their inbuild functions/methods. If you are an iOS developer, you would be spending most of your time with the XCode. Will work if the myObject have a property called foo.īut to support KVO for your custom objects you have to make use of the following methods inside object’s class. You don’t have to do anything separately to support the KVC i.e The KVC can be used for our custom objects by default. ( void ) observeValueForKeyPath :( NSString *) keyPath ofObject :( id ) object change :( NSDictionary *) change context :( void *) context When you add an object as an observer for a textfield for it’s text property, whenever the text value of the textfield changes, the observer method of the object is called with the arguments. You can observe those with the “Key Value Observing”. The UITextfield has delegate whenever it’s text changes, but it doesn’t have the delegates to inform about it’s colour changes. Key-value observing is a mechanism that allows objects to be notified of changes to specified properties of other objectsįor e.g. NSLog, ) įor e.g ] Ĭan be replaced with forKeyPath 'view.backgroundColor' ]

The above statements can be re-written by using the Key-Value coding as follows. You normally access it by calling the following accessor method of the UITextField. the UITextField has a property called text which gives the current text displayed in it. The key value coding cannot be confused with the NSDictionary’s keys.For e.g. Key value coding is a mechanism which helps us to access the properties of an object indirectly by name (or key, which is a string) rather than directly using the accessor method.

Xcode 8 mac user interface builder tutorial