Android Callback Simulation

The best way to thoroughly understand wirelessly callbacks is to write a similar implementation of the callback function in Android.

I wrote a project to implement the Setonclicklistener callback myself:

Specific directory:

Project source specific address: HTTP://PAN.BAIDU.COM/S/1C0HWPKK,

View.java: Simulates the View control in Android,

1  Packagecom.wyl.component;2 3 ImportCom.wyl.IntP.OnClickListener;4 5  Public classView {6      PublicOnclicklistener Listener;7      PublicString type;8 9     /**Ten * Two parameters of the constructor One      * @paramListener A      * @paramtype -      */ -      PublicView (Onclicklistener Listener, String type) { the         Super(); -         //This.listener = listener; -          This. Type =type; -     } +  -      PublicView (String type) { +         Super(); A          This. Type =type; at     } -  -     /** - * A constructor for a parameter -      *  -      * @paramListener in * The incoming object is an interface, -      */ to      PublicView (Onclicklistener listener) { +         Super(); -          This. Listener =Listener; the     } *      $      PublicOnclicklistener Getlistener () {Panax Notoginseng         returnListener; -     } the     /** + * This method is particularly important, A      * @paramListener the      */ +      Public voidSetlistener (Onclicklistener listener) { -          This. Listener =Listener; $     } $  -      PublicString GetType () { -         returntype; the     } - Wuyi      Public voidsetType (String type) { the          This. Type =type; -     } Wu  -     /** About * The Click () method simulates the Click event of a button and the OnClick () method of the interface is triggered by a single click $      */ -      Public voidClick () { -         if(Listener! =NULL) { -             /* A * Only if the member variable listener of the View object (Control object, such as button, etc.) is not empty + * Callback The OnClick method of the Listener interface object, which is exactly the variable of the view type the              */ -Listener. Onclick ( This); $}Else { the             //if the member variable listener of the View object (Control object, such as button, etc.) is empty, then the capture will cause an error theSystem.out.println ("To register listener first ....")); the             return; the         } -     } in}

Onclicklistener.java, is an interface,

1  PackageCom.wyl.IntP;2 3 ImportCom.wyl.component.View;4 /**5 * Simulates the Onclicklistener interface in Android,6 * There is only one onclick () method in this interface,7  * @authorAdministrator8  *9  */Ten  Public InterfaceOnclicklistener { One      Public voidOnclick (view view); A}

Test class:

1  Packagecom.wyl.test;2 3 ImportCom.wyl.IntP.OnClickListener;4 ImportCom.wyl.component.View;5 6  Public classTestclick {7      Public Static voidMain (string[] args) {8View V1 =NewView ("ListView");9V1.setlistener (NewOnclicklistener () {Ten  One @Override A              Public voidOnclick (view view) { -                 //TODO auto-generated Method Stub -System.out.println (the type of the V1 control is: "+View.gettype ()); the             } -         }); -V1. Click ();//Click () is equivalent to an event triggered when clicking on a button in Android, simulating a click event -     } +}

Operation Result:

The type of V1 control is: ListView

Android Callback Simulation