Android Learning Note ProgressBar Case study

(1)

<relativelayout 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:paddi ngbottom= "@dimen/activity_vertical_margin" android:paddingleft= "@dimen/activity_horizontal_margin" Android: paddingright= "@dimen/activity_horizontal_margin" android:paddingtop= "@dimen/activity_vertical_margin" tools: Context= ". Mainactivity "> <textview android:id=" @+id/textview1 "android:layout_width=" Wrap_content "an droid:layout_height= "Wrap_content" android:text= "progress bar use:"/> <progressbar android:id= "@+id/progress Bar1 "style="? Android:attr/progressbarstylehorizontal "Android:layout_width=" Wrap_content "Android:la        yout_height= "Wrap_content" android:layout_alignleft= "@+id/button1" android:layout_alignright= "@+id/button1"        android:layout_below= "@+id/textview1"android:layout_margintop= "30DP"/> <button android:id= "@+id/button1" android:layout_width= "Wrap_con Tent "android:layout_height=" Wrap_content "android:layout_alignleft=" @+id/textview1 "Android:layout_b elow= "@+id/progressbar1" android:layout_marginleft= "74DP" android:layout_margintop= "146DP" Android:te xt= "Download Picture"/></relativelayout>

(2)

Package Com.example.progressbar;import Android.app.activity;import Android.os.asynctask;import android.os.Bundle; Import Android.view.menu;import Android.view.view;import Android.view.view.onclicklistener;import Android.widget.button;import Android.widget.progressbar;public class Mainactivity extends Activity {private Button Button1;private ProgressBar progressBar1; @Overrideprotected void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate); Setcontentview (r.layout.activity_main); button1 = (Button) This.findviewbyid (R.id.button1); ProgressBar1 = (ProgressBar) This.findviewbyid (r.id.progressbar1);p Rogressbar1.setmax (100);// Set the maximum value to 100button1.setonclicklistener (new Onclicklistener () {@Overridepublic void OnClick (View v) {new MyTask (). Execute ();}});} Class MyTask extends Asynctask<void, Integer, void> {@Overrideprotected Void onprogressupdate (integer ... values) { Super.onprogressupdate (values);p rogressbar1.setprogress (Values[0]);} @Overrideprotected Void Doinbackground (VOID ... params) {int i = 1;while (i <=) {try {thread.sleep ()} catch (Exception e) {//Todo:handle exception}pub Lishprogress (i); i++;} return null;}} @Overridepublic boolean Oncreateoptionsmenu (Menu menu) {//Inflate the menu; This adds items to the action bar if it is PR Esent.getmenuinflater (). Inflate (R.menu.main, menu); return true;}}

(3) Presentation effect

Android Learning Note ProgressBar Case study