Display creation and invocation of multiple activity in an Android application

Layout file:

<linearlayout xmlns:android= "http://schemas.android.com/apk/res/android" xmlns:tools= "http// Schemas.android.com/tools "android:layout_width=" match_parent "android:layout_height=" Match_parent "Android:orien tation= "Vertical" tools:context= ".        Mainactivity "> <textview android:layout_width=" wrap_content "android:layout_height=" Wrap_content " android:text= "@string/hello_world"/> <button android:layout_width= "Match_parent" Android:la        yout_height= "Wrap_content" android:onclick= "openactivity" android:text= "open second activity"/> <button Android:layout_width= "Match_parent" android:layout_height= "wrap_content" android:onclick= "openSystemAc Tivity "android:text=" Open the system activity "/> <button android:layout_width=" Match_parent "Android: layout_height= "Wrap_content" android:onclick= "checkconnection" android:text= "Detect network Status"/></linearlayout& Gt

code for the main activity

Package Com.examp.manyactivity;import Android.app.activity;import Android.content.context;import Android.content.intent;import Android.net.connectivitymanager;import Android.net.networkinfo;import Android.os.bundle;import Android.view.view;import android.widget.toast;/** * Case demo is the activation activity displayed * * @author Martindong * */public class Mainactivity extends Activity {@Overrideprotected void onCreate (Bundle savedinstancestate) {s Uper.oncreate (savedinstancestate); Setcontentview (R.layout.activity_main);} /** * User wants to open the second interface when * * @param view */public void openactivity (view view) {//Create intent Object Intent Intent = new intent ();//Convenient to call SetComponent with a clear class name. Equivalent to creating a new component//session Location | Specifies the detailed activityintent.setclassname (this, "com.examp.manyactivity.SecondActivity") to be activated;// Another way to do this is to specify activity//Intent intent2 = new Intent (this, secondactivity.class) when creating the intent object;//Activating a activitystartactivity (intent);} /** * Open the activity<br> in the system * Case demo is to open the library activity * * @param view */public void opensystemactivity (view view) {/* * 05-31 07:42:44.581:i/activitymanager: START * {Act=android.intent.action.main * cat=[ Android.intent.category.LAUNCHER] flg=0x10200000 * Cmp=com.android.gallery/com.android.camera.gallerypicker u=0} from * pid 282 */intent Intent = new Intent (); Intent.setclassname ("Com.android.gallery", " Com.android.camera.GalleryPicker "); StartActivity (intent);} /** * Detect Network status * * @param view */public void checkconnection (view view) {/* * 05-31 08:03:01.848:i/activitymanager ($): S Tart * {Act=android.intent.action.main cmp=com.android.settings/. Subsettings * (have extras) u=0} from PID 306 because 4.0 of the network management needs to pass in additional data, this feature uses 2.3 of the virtual machine <br> * 05-31 08:05:47.072:i/activity Manager: starting:intent {* Act=android.intent.action.main * cmp=com.android.settings/. Wirelesssettings} from PID 168 *///Check the connection status of the network//Create connection management Object Connectivitymanager cm = (Connectivitymanager) this.getsystemser Vice (context.connectivity_service);//required Permissions for Android. manifest.permission.access_network_state//getting connection information for a network networkinfo info =Cm.getactivenetworkinfo ();//Assume that no matter what the network information info for null;if (info! = null && info.isconnected ()) {Toast.maketext ( This, "Network available ...", Toast.length_short). Show (); else {Toast.maketext (this, "Network not available, set ...", Toast.length_short). Show (); Intent Intent = new Intent (); Intent.setclassname ("Com.android.settings", "com.android.settings.WirelessSettings"); StartActivity (intent);}}

A second activity file:

Package Com.examp.manyactivity;import Android.app.activity;import android.os.bundle;/** * self-defined activity<br> * Must inherit activity<br> * activity is one of the four components of the system <br> * operating system to find the activity, you must register it in the manifest file Androidmanifest.xml <br > * * *  @author martindong *  */public class Secondactivity extends Activity {/** * Generally overrides the method, mostly to initialize some data, and program Interface <br> * Call when activity is created */@Overrideprotected void onCreate (Bundle savedinstancestate) {super.oncreate ( savedinstancestate);//Set the displayed layout Setcontentview (R.layout.activity_tow);}}

The second activity corresponds to the layout file:

<?xml version= "1.0" encoding= "Utf-8"? ><linearlayout xmlns:android= "http://schemas.android.com/apk/res/ Android "Android:layout_width=" Match_parent "android:layout_height=" match_parent "android:orientation=" vertical " > <ratingbar android:id= "@+id/ratingbar1" android:layout_width= "Wrap_content" android:layout _height= "Wrap_content"/> <ratingbar android:id= "@+id/ratingbar2" android:layout_width= "Wrap_conten        T "android:layout_height=" wrap_content "/> <checkedtextview android:id=" @+id/checkedtextview1 " Android:layout_width= "Wrap_content" android:layout_height= "wrap_content" android:text= "CheckedTextView"/ > <spinner android:id= "@+id/spinner1" android:layout_width= "Match_parent" Android:layout_hei ght= "Wrap_content"/> <progressbar android:id= "@+id/progressbar1" style= "? Android:attr/progressbars Tylehorizontal "Android:layoUt_width= "Wrap_content" android:layout_height= "wrap_content"/> <progressbar android:id= "@+id/progr EssBar2 "style="? Android:attr/progressbarstylelarge "Android:layout_width=" 246DP "Android:layout_heig ht= "Match_parent"/></linearlayout>

Configuration of the manifest file:

<?xml version= "1.0" encoding= "Utf-8"? ><manifest xmlns:android= "http://schemas.android.com/apk/res/        Android "package=" Com.examp.manyactivity "android:versioncode=" 1 "android:versionname=" 1.0 "> <uses-sdk android:minsdkversion= "8" android:targetsdkversion= "/>" <!--icon: Specifies the application's icons; Label: Specifies the name of the application; --<uses-permission android:name= "Android.permission.ACCESS_NETWORK_STATE"/> <application androi D:allowbackup= "true" android:icon= "@drawable/ic_launcher" android:label= "@string/app_name" android:th Eme= "@style/apptheme" > <!--activity-<!--assuming that the activity does not icon,label settings, the app will be used by default Applicati On the Icon,label settings--<!--name specifies the corresponding activity class for the layout file--<activity android:name= "COM.E Xamp.manyactivity.MainActivity "android:label=" @string/app_name "> <!----> &lt ;intent-filter> <!--Tell Android system This is the app's main interface--<action android:name= "Android.intent.action.MAIN"/> <!            --Tell the Android system to create an app icon--<category android:name= "Android.intent.category.LAUNCHER"/> </intent-filter> </activity> <activity android:name= "Com.examp.manyactivity.Seco Ndactivity "android:label=" @string/app_name "> </activity> </application></manifest >

Note: The Network view status of this case can only be used on the simulator of 2.3;

Demo Source code Download:

http://download.csdn.net/detail/u011936142/7429455

Display creation and invocation of multiple activity in an Android application