Android计时器控件Chronometer应用实例

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:tools="http://schemas.android.com/tools"  android:id="@+id/LinearLayout1"  android:layout_width="match_parent"  android:layout_height="match_parent"  android:orientation="horizontal"  android:paddingBottom="@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"  android:background="@drawable/bg" >   <Chronometer   android:id="@+id/chronometer"   android:layout_marginTop="8dp"   android:layout_marginLeft="5dp"   android:layout_width="wrap_content"   android:layout_height="wrap_content" />   <Button   android:id="@+id/restart"   android:layout_width="wrap_content"   android:layout_height="wrap_content"   android:text="重置"   android:visibility="gone" />  </LinearLayout>