Project name: P0101 Listener Build Target: Android

Project name: P0102_ActivityListener
Build Target: Android 2.3.3
Application name: ActivityListener
Package name: en. startandroid. develop.activitylistener
Create Activity: MainActivity

Let's take the same screen again:

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xmlns:android="http://schemas.android.com/apk/res/android"     android:layout_height="match_parent"     android:layout_width="match_parent"     android:orientation="horizontal">              android:id="@+id/linearLayout1"         android:layout_height="match_parent"         android:orientation="vertical"         android:layout_width="match_parent"         android:layout_margin="30dp">                      android:layout_width="wrap_content"             android:text="TextView"             android:layout_height="wrap_content"             android:id="@+id/tvOut"             android:layout_gravity="center_horizontal"             android:layout_marginBottom="50dp">                               android:layout_height="wrap_content"             android:layout_gravity="center_horizontal"             android:id="@+id/btnOk"             android:text="OK"             android:layout_width="100dp">                               android:layout_height="wrap_content"             android:layout_gravity="center_horizontal"             android:id="@+id/btnCancel"             android:text="Cancel"             android:layout_width="100dp">

 

Prepare objects and add an implementation of the interface (implements OnClickListener)

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public class MainActivity extends Activity implements OnClickListener {       TextView tvOut;    Button btnOk;    Button btnCancel;       /** Called when the activity is first created. */    @Override    public void onCreate(Bundle savedInstanceState) {      super.onCreate(savedInstanceState);      setContentView(R.layout.main);         // найдем View-elements      tvOut = (TextView) findViewById(R.id.tvOut);      btnOk = (Button) findViewById(R.id.btnOk);      btnCancel = (Button) findViewById(R.id.btnCancel);    }  }

 

OnClickListener is highlighted in red because it is not included in the import. So CTRL+SHIFT+O and select View. OnClickListener.

Now Eclipse swears at the MainActivity class. This happens because the class