Some ways Android operates the UI thread

We often do time-consuming operations in a background thread, such as going to the network to fetch data. But when the data is retrieved and needs to be displayed on the page, there are some minor problems, as we all know that the Android UI page is not allowed to operate directly on other threads. The following is a summary of the 4 methods used to manipulate the UI interface in a thread.

Simulate time-consuming operations

Private void throws interruptedexception {        thread.sleep);}

Method One: Handler

The event is sent through the handler SendMessage (msg) in the child thread:

Private voidmethod1 () {NewThread (NewRunnable () {@Override Public voidrun () {Try {                //time-consuming Operationconnectnet (); //send a message to handlerMhadndler.sendemptymessage (111); } Catch(interruptedexception e) {e.printstacktrace (); }}). Start ();}

Method Two: View.post (Runnable)

Private voidmethod2 () {Mytext.setonclicklistener (NewView.onclicklistener () {@Override Public voidOnClick (View v) {NewThread (NewRunnable () {@Override Public voidrun () {Try {                        //time-consuming Operationconnectnet (); Mytext.post (NewRunnable () {@Override Public voidrun () {Mytext.settext ("End of networking, update UI data");                    }                        }); } Catch(interruptedexception e) {e.printstacktrace ();        }}). Start (); }    });}

Method Three: Activity.runonuithread

Similar to View.post

Private voidmethod3 () {NewThread (NewRunnable () {@Override Public voidrun () {Try {                //time-consuming Operationconnectnet (); Runonuithread (NewRunnable () {@Override Public voidrun () {Mytext.settext ("Runonuithread ...");            }                }); } Catch(interruptedexception e) {e.printstacktrace (); }}). Start ();}

method Four: Asynctask

Private voidmethod4 () {//executing in the UI thread    NewLoadtask (). Execute ("www.91dota.com");}Private classLoadtaskextendsAsynctask {protected voidOnPostExecute (String result) {Mytext.settext (result);//get information from the Network Refresh page    }    protectedString Doinbackground (object[] objects) {return"......";//background time-consuming operations    }}

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Attach code and layout

Mainactivity.java

 Public classMainactivityextendsappcompatactivity {PrivateTextView MyText; PrivateHandler Mhadndler =NewHandler () {@Override Public voidhandlemessage (Message msg) {Super. Handlemessage (msg); Mytext.settext ("Get the message ..." +msg.what);    }    }; @Overrideprotected voidonCreate (Bundle savedinstancestate) {Super. OnCreate (savedinstancestate);        Setcontentview (R.layout.activity_main); MyText=Findviewbyid (R.id.mytextview); }    /*** Method One: Handler*/    Private voidmethod1 () {NewThread (NewRunnable () {@Override Public voidrun () {Try {                    //time-consuming Operationconnectnet (); //send a message to handlerMhadndler.sendemptymessage (111); } Catch(interruptedexception e) {e.printstacktrace ();    }}). Start (); }    /*** Method Two: Through View.post (Runnable)*/    Private voidmethod2 () {Mytext.setonclicklistener (NewView.onclicklistener () {@Override Public voidOnClick (View v) {NewThread (NewRunnable () {@Override Public voidrun () {Try {                            //time-consuming Operationconnectnet (); Mytext.post (NewRunnable () {@Override Public voidrun () {Mytext.settext ("End of networking, update UI data");                        }                            }); } Catch(interruptedexception e) {e.printstacktrace ();            }}). Start ();    }        }); }    /*** Method Three: Activity.runonuithread (Runnable)*/    Private voidmethod3 () {Runonuithread (NewRunnable () {@Override Public voidrun () {Try {                    //time-consuming Operationconnectnet (); Mytext.settext ("Runonuithread ..."); } Catch(interruptedexception e) {e.printstacktrace ();    }            }        }); }    /*** Method Four: Asynctask*/    Private voidmethod4 () {//executing in the UI thread        NewLoadtask (). Execute ("www.91dota.com"); }    Private classLoadtaskextendsAsynctask {protected voidOnPostExecute (String result) {Mytext.settext (result);//get information from the Network Refresh page        }        protectedString Doinbackground (object[] objects) {return"......";//background time-consuming operations        }    }    Private voidConnectNet ()throwsinterruptedexception {thread.sleep (2000); }}

Activity_main.xml

<?XML version= "1.0" encoding= "Utf-8"?><LinearLayoutxmlns:android= "Http://schemas.android.com/apk/res/android"Xmlns:app= "Http://schemas.android.com/apk/res-auto"Xmlns:tools= "Http://schemas.android.com/tools"Android:layout_width= "Match_parent"Android:layout_height= "Match_parent"android:orientation= "vertical">    <TextViewAndroid:id= "@+id/mytextview"Android:layout_width= "Match_parent"Android:layout_height= "50DP"Android:layout_margin= "10DP"Android:background= "#dea"android:gravity= "Center"Android:text= "Hello world!" /></LinearLayout>

Reference: Http://www.it165.net

Some ways Android operates the UI thread