Android Master Advanced Tutorial (ix)----the use of Android handler!!!

Hello, everybody. We are talking about the use of Android handler in this section, before we talk about handler, let us ask a small question, is how to let the program 5 seconds to update the title.

First we look at the people who are accustomed to Java programming, how to write a program before they know how to use handler, the code is as follows:

[Java] View plain copy PackageCom.android.tutor; ImportJava.util.Timer; ImportJava.util.TimerTask; Importandroid.app.Activity; ImportAndroid.os.Bundle;  Public classHandlerdemoextendsActivity {//The title provides a variable for the Settitle method, which I set as the int type for convenience.    Private inttitle = 0;  Public voidonCreate (Bundle savedinstancestate) {Super. OnCreate (savedinstancestate);                    Setcontentview (R.layout.main); Timer Timer=NewTimer (); Timer.scheduleatfixedrate (NewMyTask (), 1, 5000); }                Private classMyTaskextendstimertask{@Override Public voidrun () {Settitle ("Welcome to Mr Wei ' s blog" +title); Title++; }         }  }

Android introduces handler, a special class that can be said to be a bridge between runnable and activity interactions, so we just send a message in the Run method, and in handler, we perform different tasks with different messages.

 PackageCom.android.tutor; ImportJava.util.Timer; ImportJava.util.TimerTask; Importandroid.app.Activity; ImportAndroid.os.Bundle; ImportAndroid.os.Handler; ImportAndroid.os.Message;  Public classHandlerdemoextendsActivity {//The title provides a variable for the Settitle method, which I set as the int type for convenience.    Private inttitle = 0; PrivateHandler Mhandler =NewHandler () { Public voidhandlemessage (Message msg) {Switch(msg.what) { Case1: Updatetitle ();  Break;      }          };      };  Public voidonCreate (Bundle savedinstancestate) {Super. OnCreate (savedinstancestate);                    Setcontentview (R.layout.main); Timer Timer=NewTimer (); Timer.scheduleatfixedrate (NewMyTask (), 1, 5000); }                Private classMyTaskextendstimertask{@Override Public voidrun () {Message message=NewMessage (); Message.what= 1;                        Mhandler.sendmessage (message); }         }                   Public voidUpdatetitle () {Settitle ("Welcome to Mr Wei ' s blog" +title); Title++; }  }

Let's look at the following:

Android Master Advanced Tutorial (ix)----the use of Android handler!!!