Dagger

## Constructor Injection
- @Inject before constructor to tell dagger how to instantiate object
- @component : before interface to tell dagger to implement this interface to provide us with required fields

## Field Injection:  @Inject before fields/variable 

## Method Injection: @Inject before method to be called after constructor/creating instance 
 
## Module and Provider: sometimes we can’t modify the constructor of objects (like classes that belong to 3rd party libraries.),  in this case we should
- Create module class and annotate it with @module
- Create methods that instantiate this field and annotate it with @Provides
- Add this module to Component class

## Interface Injection: 
Create abstract Module class and annotate it with @module
Create abstract method and annotate it with @Binds
Add this module to Component class

@Singleton is the only scope annotation that comes with the javax.inject package. You can use it to annotate ApplicationComponent and the objects you want to reuse across the whole application.