到目前为止，这个应用程序的唯一任务是在我水平滑动屏幕时滑动。但是当我在我的 Android 虚拟机上运行它时，logcat 会弹出这些错误：
04-14 16:14:17.822: D/ddm-heap(196): Got feature list request
04-14 16:14:18.193: D/AndroidRuntime(196): Shutting down VM
04-14 16:14:18.193: W/dalvikvm(196): threadid=3: thread exiting with uncaught exception (group=0x4001b188)
04-14 16:14:18.193: E/AndroidRuntime(196): Uncaught handler: thread main exiting due to uncaught exception
04-14 16:14:18.313: E/AndroidRuntime(196): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{stc1.hello.here/stc1.hello.here.Stc1Activity}: java.lang.ClassNotFoundException: stc1.hello.here.Stc1Activity in loader dalvik.system.PathClassLoader@44c067e8
04-14 16:14:18.313: E/AndroidRuntime(196): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2417)
04-14 16:14:18.313: E/AndroidRuntime(196): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2512)
04-14 16:14:18.313: E/AndroidRuntime(196): at android.app.ActivityThread.access$2200(ActivityThread.java:119)
04-14 16:14:18.313: E/AndroidRuntime(196): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1863)
04-14 16:14:18.313: E/AndroidRuntime(196): at android.os.Handler.dispatchMessage(Handler.java:99)
04-14 16:14:18.313: E/AndroidRuntime(196): at android.os.Looper.loop(Looper.java:123)
04-14 16:14:18.313: E/AndroidRuntime(196): at android.app.ActivityThread.main(ActivityThread.java:4363)
04-14 16:14:18.313: E/AndroidRuntime(196): at java.lang.reflect.Method.invokeNative(Native Method)
04-14 16:14:18.313: E/AndroidRuntime(196): at java.lang.reflect.Method.invoke(Method.java:521)
04-14 16:14:18.313: E/AndroidRuntime(196): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
04-14 16:14:18.313: E/AndroidRuntime(196): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
04-14 16:14:18.313: E/AndroidRuntime(196): at dalvik.system.NativeStart.main(Native Method)
04-14 16:14:18.313: E/AndroidRuntime(196): Caused by: java.lang.ClassNotFoundException: stc1.hello.here.Stc1Activity in loader dalvik.system.PathClassLoader@44c067e8
04-14 16:14:18.313: E/AndroidRuntime(196): at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:243)
04-14 16:14:18.313: E/AndroidRuntime(196): at java.lang.ClassLoader.loadClass(ClassLoader.java:573)
04-14 16:14:18.313: E/AndroidRuntime(196): at java.lang.ClassLoader.loadClass(ClassLoader.java:532)
04-14 16:14:18.313: E/AndroidRuntime(196): at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
04-14 16:14:18.313: E/AndroidRuntime(196): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2409)
04-14 16:14:18.313: E/AndroidRuntime(196): ... 11 more
04-14 16:14:18.403: I/dalvikvm(196): threadid=7: reacting to signal 3
04-14 16:14:18.413: E/dalvikvm(196): Unable to open stack trace file '/data/anr/traces.txt': Permission denied
04-14 16:14:35.972: D/AndroidRuntime(228): Shutting down VM
04-14 16:14:36.052: W/dalvikvm(228): threadid=3: thread exiting with uncaught exception (group=0x4001b188)
04-14 16:14:36.052: E/AndroidRuntime(228): Uncaught handler: thread main exiting due to uncaught exception
04-14 16:14:36.112: E/AndroidRuntime(228): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{stc1.hello.here/stc1.hello.here.Stc1Activity}: java.lang.ClassNotFoundException: stc1.hello.here.Stc1Activity in loader dalvik.system.PathClassLoader@44e8c7e8
04-14 16:14:36.112: E/AndroidRuntime(228): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2417)
04-14 16:14:36.112: E/AndroidRuntime(228): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2512)
04-14 16:14:36.112: E/AndroidRuntime(228): at android.app.ActivityThread.access$2200(ActivityThread.java:119)
04-14 16:14:36.112: E/AndroidRuntime(228): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1863)
04-14 16:14:36.112: E/AndroidRuntime(228): at android.os.Handler.dispatchMessage(Handler.java:99)
04-14 16:14:36.112: E/AndroidRuntime(228): at android.os.Looper.loop(Looper.java:123)
04-14 16:14:36.112: E/AndroidRuntime(228): at android.app.ActivityThread.main(ActivityThread.java:4363)
04-14 16:14:36.112: E/AndroidRuntime(228): at java.lang.reflect.Method.invokeNative(Native Method)
04-14 16:14:36.112: E/AndroidRuntime(228): at java.lang.reflect.Method.invoke(Method.java:521)
04-14 16:14:36.112: E/AndroidRuntime(228): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
04-14 16:14:36.112: E/AndroidRuntime(228): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
04-14 16:14:36.112: E/AndroidRuntime(228): at dalvik.system.NativeStart.main(Native Method)
04-14 16:14:36.112: E/AndroidRuntime(228): Caused by: java.lang.ClassNotFoundException: stc1.hello.here.Stc1Activity in loader dalvik.system.PathClassLoader@44e8c7e8
04-14 16:14:36.112: E/AndroidRuntime(228): at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:243)
04-14 16:14:36.112: E/AndroidRuntime(228): at java.lang.ClassLoader.loadClass(ClassLoader.java:573)
04-14 16:14:36.112: E/AndroidRuntime(228): at java.lang.ClassLoader.loadClass(ClassLoader.java:532)
04-14 16:14:36.112: E/AndroidRuntime(228): at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
04-14 16:14:36.112: E/AndroidRuntime(228): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2409)
04-14 16:14:36.112: E/AndroidRuntime(228): ... 11 more
04-14 16:14:36.174: I/dalvikvm(228): threadid=7: reacting to signal 3
04-14 16:14:36.174: E/dalvikvm(228): Unable to open stack trace file '/data/anr/traces.txt': Permission denied
这是 FragmentActivity.java：
package stc1.hello.here;
import android.app.Activity;
import android.content.Context;
import android.graphics.Color;
import android.os.Bundle;
import android.os.Parcelable;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.View;
import android.widget.TextView;
public class FragmentActivity extends Activity {
//We declare how many pages we want here.
private ViewPager awesomePager;
private static int NUM_AWESOME_VIEWS = 20;
private Context cxt;
private AwesomePagerAdapter awesomeAdapter;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main1);
cxt = this;
awesomeAdapter = new AwesomePagerAdapter();
awesomePager = (ViewPager) findViewById(R.layout.main1);
awesomePager.setAdapter(awesomeAdapter);
}
private class AwesomePagerAdapter extends PagerAdapter{
@Override
public int getCount() {
return NUM_AWESOME_VIEWS;
}
/**
* Create the page for the given position. The adapter is responsible
* for adding the view to the container given here, although it only
* must ensure this is done by the time it returns from
* {@link #finishUpdate()}.
*
* @param container The containing View in which the page will be shown.
* @param position The page position to be instantiated.
* @return Returns an Object representing the new page. This does not
* need to be a View, but can be some other container of the page.
*/
@Override
public Object instantiateItem(View collection, int position) {
TextView tv = new TextView(cxt);
tv.setText("Bonjour PAUG " + position);
tv.setTextColor(Color.WHITE);
tv.setTextSize(30);
((ViewPager) collection).addView(tv,0);
return tv;
}
/**
* Remove a page for the given position. The adapter is responsible
* for removing the view from its container, although it only must ensure
* this is done by the time it returns from {@link #finishUpdate()}.
*
* @param container The containing View from which the page will be removed.
* @param position The page position to be removed.
* @param object The same object that was returned by
* {@link #instantiateItem(View, int)}.
*/
@Override
public void destroyItem(View collection, int position, Object view) {
((ViewPager) collection).removeView((TextView) view);
}
@Override
public boolean isViewFromObject(View view, Object object) {
return view==((TextView)object);
}
/**
* Called when the a change in the shown pages has been completed. At this
* point you must ensure that all of the pages have actually been added or
* removed from the container as appropriate.
* @param container The containing View which is displaying this adapter's
* page views.
*/
@Override
public void finishUpdate(View arg0) {}
@Override
public void restoreState(Parcelable arg0, ClassLoader arg1) {}
@Override
public Parcelable saveState() {
return null;
}
@Override
public void startUpdate(View arg0) {}
}
}
这是main1.xml：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
>
<android.support.v4.view.ViewPager
android:id="@+android:id/viewpager"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
/>
</LinearLayout>