package com.example.swipetabs;
import android.annotation.SuppressLint;
import android.app.ActionBar;
import android.app.ActionBar.Tab;
import android.app.ActionBar.TabListener;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentStatePagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.view.Window;
@SuppressLint("NewApi") public class MainActivity extends FragmentActivity implements TabListener {
ViewPager page;
@SuppressLint("NewApi") @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().requestFeature(Window.FEATURE_ACTION_BAR);
setContentView(R.layout.activity_main);
final ActionBar actionBar=getActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
Tab tab1=actionBar.newTab();
Tab tab2=actionBar.newTab();
Tab tab3=actionBar.newTab();
tab1.setTabListener(this);
tab2.setTabListener(this);
tab3.setTabListener(this);
tab1.setText("sparta1");
tab2.setText("sparta2");
tab3.setText("sparta3");
actionBar.addTab(tab1);
actionBar.addTab(tab2);
actionBar.addTab(tab3);
page=new ViewPager(this);
page=(ViewPager)findViewById(R.id.pager);
FragmentManager manager=getSupportFragmentManager();
MyFragmentStatePagerAdapter pagerAdapter=new MyFragmentStatePagerAdapter(manager);
page.setAdapter(pagerAdapter);
page.setOnPageChangeListener(new OnPageChangeListener() {
@Override
public void onPageSelected(int arg0) {
actionBar.setSelectedNavigationItem(arg0);
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
// TODO Auto-generated method stub
}
@Override
public void onPageScrollStateChanged(int arg0) {
// TODO Auto-generated method stub
}
});
//page.setCurrentItem(2);
}
@Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
page.setCurrentItem(tab.getPosition());
}
@Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
}
@Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
// TODO Auto-generated method stub
}
class MyFragmentStatePagerAdapter extends FragmentStatePagerAdapter{
public MyFragmentStatePagerAdapter(FragmentManager fm) {
super(fm);
// TODO Auto-generated constructor stub
}
@Override
public Fragment getItem(int arg0) {
Fragment fragment=null;
if(arg0==0){
fragment=new FragmentA();
}
if(arg0==1){
fragment=new FragmentB();
}
if(arg0==2){
fragment=new FragmentC();
}
return fragment;
}
@Override
public int getCount() {
return 3;
}
}
}
public void onTabSelected(Tab tab, FragmentTransaction ft) {
page.setCurrentItem(tab.getPosition());
}
上面的page.setCurrentItem（tab.getPosition（））返回null异常。我无法弄清楚问题。我希望有人能够弄明白。 谢谢 这是错误日志
10-18 16:04:15.496: D/AndroidRuntime(1794): Shutting down VM
10-18 16:04:15.496: W/dalvikvm(1794): threadid=1: thread exiting with uncaught exception (group=0x41c18ba8)
10-18 16:04:15.496: E/AndroidRuntime(1794): FATAL EXCEPTION: main
10-18 16:04:15.496: E/AndroidRuntime(1794): Process: com.example.swipetabs, PID: 1794
10-18 16:04:15.496: E/AndroidRuntime(1794): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.swipetabs/com.example.swipetabs.MainActivity}: java.lang.NullPointerException
10-18 16:04:15.496: E/AndroidRuntime(1794): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2184)
10-18 16:04:15.496: E/AndroidRuntime(1794): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
10-18 16:04:15.496: E/AndroidRuntime(1794): at android.app.ActivityThread.access$800(ActivityThread.java:135)
10-18 16:04:15.496: E/AndroidRuntime(1794): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
10-18 16:04:15.496: E/AndroidRuntime(1794): at android.os.Handler.dispatchMessage(Handler.java:102)
10-18 16:04:15.496: E/AndroidRuntime(1794): at android.os.Looper.loop(Looper.java:136)
10-18 16:04:15.496: E/AndroidRuntime(1794): at android.app.ActivityThread.main(ActivityThread.java:5001)
10-18 16:04:15.496: E/AndroidRuntime(1794): at java.lang.reflect.Method.invokeNative(Native Method)
10-18 16:04:15.496: E/AndroidRuntime(1794): at java.lang.reflect.Method.invoke(Method.java:515)
10-18 16:04:15.496: E/AndroidRuntime(1794): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
10-18 16:04:15.496: E/AndroidRuntime(1794): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
10-18 16:04:15.496: E/AndroidRuntime(1794): at dalvik.system.NativeStart.main(Native Method)
10-18 16:04:15.496: E/AndroidRuntime(1794): Caused by: java.lang.NullPointerException
10-18 16:04:15.496: E/AndroidRuntime(1794): at com.example.swipetabs.MainActivity.onTabSelected(MainActivity.java:68)
10-18 16:04:15.496: E/AndroidRuntime(1794): at com.android.internal.app.ActionBarImpl.selectTab(ActionBarImpl.java:577)
10-18 16:04:15.496: E/AndroidRuntime(1794): at com.android.internal.app.ActionBarImpl.addTab(ActionBarImpl.java:506)
10-18 16:04:15.496: E/AndroidRuntime(1794): at com.android.internal.app.ActionBarImpl.addTab(ActionBarImpl.java:492)
10-18 16:04:15.496: E/AndroidRuntime(1794): at com.example.swipetabs.MainActivity.onCreate(MainActivity.java:33)
10-18 16:04:15.496: E/AndroidRuntime(1794): at android.app.Activity.performCreate(Activity.java:5231)
10-18 16:04:15.496: E/AndroidRuntime(1794): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
10-18 16:04:15.496: E/AndroidRuntime(1794): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148)
10-18 16:04:15.496: E/AndroidRuntime(1794): ... 11 more
10-18 16:05:24.880: I/Adreno-EGL(1966): <qeglDrvAPI_eglInitialize:320>: EGL 1.4 QUALCOMM Build: I0404c4692afb8623f95c43aeb6d5e13ed4b30ddbDate: 11/06/13
10-18 16:05:24.931: D/OpenGLRenderer(1966): Enabling debug mode 0
10-18 16:08:35.814: D/dalvikvm(1966): GC_FOR_ALLOC freed 207K, 3% free 9291K/9528K, paused 16ms, total 16ms
10-18 16:08:47.997: I/Adreno-EGL(2310): <qeglDrvAPI_eglInitialize:320>: EGL 1.4 QUALCOMM Build: I0404c4692afb8623f95c43aeb6d5e13ed4b30ddbDate: 11/06/13
10-18 16:08:48.037: D/OpenGLRenderer(2310): Enabling debug mode 0
10-18 16:09:41.394: D/AndroidRuntime(2457): Shutting down VM
10-18 16:09:41.394: W/dalvikvm(2457): threadid=1: thread exiting with uncaught exception (group=0x41c18ba8)
10-18 16:09:41.394: E/AndroidRuntime(2457): FATAL EXCEPTION: main
10-18 16:09:41.394: E/AndroidRuntime(2457): Process: com.example.swipetabs, PID: 2457
10-18 16:09:41.394: E/AndroidRuntime(2457): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.swipetabs/com.example.swipetabs.MainActivity}: java.lang.NullPointerException
10-18 16:09:41.394: E/AndroidRuntime(2457): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2184)
10-18 16:09:41.394: E/AndroidRuntime(2457): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
10-18 16:09:41.394: E/AndroidRuntime(2457): at android.app.ActivityThread.access$800(ActivityThread.java:135)
10-18 16:09:41.394: E/AndroidRuntime(2457): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
10-18 16:09:41.394: E/AndroidRuntime(2457): at android.os.Handler.dispatchMessage(Handler.java:102)
10-18 16:09:41.394: E/AndroidRuntime(2457): at android.os.Looper.loop(Looper.java:136)
10-18 16:09:41.394: E/AndroidRuntime(2457): at android.app.ActivityThread.main(ActivityThread.java:5001)
10-18 16:09:41.394: E/AndroidRuntime(2457): at java.lang.reflect.Method.invokeNative(Native Method)
10-18 16:09:41.394: E/AndroidRuntime(2457): at java.lang.reflect.Method.invoke(Method.java:515)
10-18 16:09:41.394: E/AndroidRuntime(2457): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
10-18 16:09:41.394: E/AndroidRuntime(2457): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
10-18 16:09:41.394: E/AndroidRuntime(2457): at dalvik.system.NativeStart.main(Native Method)
10-18 16:09:41.394: E/AndroidRuntime(2457): Caused by: java.lang.NullPointerException
10-18 16:09:41.394: E/AndroidRuntime(2457): at com.example.swipetabs.MainActivity.onTabSelected(MainActivity.java:66)
10-18 16:09:41.394: E/AndroidRuntime(2457): at com.android.internal.app.ActionBarImpl.selectTab(ActionBarImpl.java:577)
10-18 16:09:41.394: E/AndroidRuntime(2457): at com.android.internal.app.ActionBarImpl.addTab(ActionBarImpl.java:506)
10-18 16:09:41.394: E/AndroidRuntime(2457): at com.android.internal.app.ActionBarImpl.addTab(ActionBarImpl.java:492)
10-18 16:09:41.394: E/AndroidRuntime(2457): at com.example.swipetabs.MainActivity.onCreate(MainActivity.java:33)
10-18 16:09:41.394: E/AndroidRuntime(2457): at android.app.Activity.performCreate(Activity.java:5231)
10-18 16:09:41.394: E/AndroidRuntime(2457): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
10-18 16:09:41.394: E/AndroidRuntime(2457): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148)
10-18 16:09:41.394: E/AndroidRuntime(2457): ... 11 more
10-18 16:11:01.960: I/Adreno-EGL(2680): <qeglDrvAPI_eglInitialize:320>: EGL 1.4 QUALCOMM Build: I0404c4692afb8623f95c43aeb6d5e13ed4b30ddbDate: 11/06/13
10-18 16:11:01.990: D/OpenGLRenderer(2680): Enabling debug mode 0
10-18 16:12:30.865: D/AndroidRuntime(3006): Shutting down VM
10-18 16:12:30.865: W/dalvikvm(3006): threadid=1: thread exiting with uncaught exception (group=0x41c18ba8)
10-18 16:12:30.865: E/AndroidRuntime(3006): FATAL EXCEPTION: main
10-18 16:12:30.865: E/AndroidRuntime(3006): Process: com.example.swipetabs, PID: 3006
10-18 16:12:30.865: E/AndroidRuntime(3006): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.swipetabs/com.example.swipetabs.MainActivity}: java.lang.NullPointerException
10-18 16:12:30.865: E/AndroidRuntime(3006): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2184)
10-18 16:12:30.865: E/AndroidRuntime(3006): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
10-18 16:12:30.865: E/AndroidRuntime(3006): at android.app.ActivityThread.access$800(ActivityThread.java:135)
10-18 16:12:30.865: E/AndroidRuntime(3006): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
10-18 16:12:30.865: E/AndroidRuntime(3006): at android.os.Handler.dispatchMessage(Handler.java:102)
10-18 16:12:30.865: E/AndroidRuntime(3006): at android.os.Looper.loop(Looper.java:136)
10-18 16:12:30.865: E/AndroidRuntime(3006): at android.app.ActivityThread.main(ActivityThread.java:5001)
10-18 16:12:30.865: E/AndroidRuntime(3006): at java.lang.reflect.Method.invokeNative(Native Method)
10-18 16:12:30.865: E/AndroidRuntime(3006): at java.lang.reflect.Method.invoke(Method.java:515)
10-18 16:12:30.865: E/AndroidRuntime(3006): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
10-18 16:12:30.865: E/AndroidRuntime(3006): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
10-18 16:12:30.865: E/AndroidRuntime(3006): at dalvik.system.NativeStart.main(Native Method)
10-18 16:12:30.865: E/AndroidRuntime(3006): Caused by: java.lang.NullPointerException
10-18 16:12:30.865: E/AndroidRuntime(3006): at com.example.swipetabs.MainActivity.onTabSelected(MainActivity.java:67)
10-18 16:12:30.865: E/AndroidRuntime(3006): at com.android.internal.app.ActionBarImpl.selectTab(ActionBarImpl.java:577)
10-18 16:12:30.865: E/AndroidRuntime(3006): at com.android.internal.app.ActionBarImpl.addTab(ActionBarImpl.java:506)
10-18 16:12:30.865: E/AndroidRuntime(3006): at com.android.internal.app.ActionBarImpl.addTab(ActionBarImpl.java:492)
10-18 16:12:30.865: E/AndroidRuntime(3006): at com.example.swipetabs.MainActivity.onCreate(MainActivity.java:33)
10-18 16:12:30.865: E/AndroidRuntime(3006): at android.app.Activity.performCreate(Activity.java:5231)
10-18 16:12:30.865: E/AndroidRuntime(3006): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
10-18 16:12:30.865: E/AndroidRuntime(3006): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148)
10-18 16:12:30.865: E/AndroidRuntime(3006): ... 11 more
10-18 16:21:28.038: D/AndroidRuntime(3720): Shutting down VM
10-18 16:21:28.038: W/dalvikvm(3720): threadid=1: thread exiting with uncaught exception (group=0x41c18ba8)
10-18 16:21:28.038: E/AndroidRuntime(3720): FATAL EXCEPTION: main
10-18 16:21:28.038: E/AndroidRuntime(3720): Process: com.example.swipetabs, PID: 3720
10-18 16:21:28.038: E/AndroidRuntime(3720): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.swipetabs/com.example.swipetabs.MainActivity}: java.lang.NullPointerException
10-18 16:21:28.038: E/AndroidRuntime(3720): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2184)
10-18 16:21:28.038: E/AndroidRuntime(3720): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
10-18 16:21:28.038: E/AndroidRuntime(3720): at android.app.ActivityThread.access$800(ActivityThread.java:135)
10-18 16:21:28.038: E/AndroidRuntime(3720): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
10-18 16:21:28.038: E/AndroidRuntime(3720): at android.os.Handler.dispatchMessage(Handler.java:102)
10-18 16:21:28.038: E/AndroidRuntime(3720): at android.os.Looper.loop(Looper.java:136)
10-18 16:21:28.038: E/AndroidRuntime(3720): at android.app.ActivityThread.main(ActivityThread.java:5001)
10-18 16:21:28.038: E/AndroidRuntime(3720): at java.lang.reflect.Method.invokeNative(Native Method)
10-18 16:21:28.038: E/AndroidRuntime(3720): at java.lang.reflect.Method.invoke(Method.java:515)
10-18 16:21:28.038: E/AndroidRuntime(3720): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
10-18 16:21:28.038: E/AndroidRuntime(3720): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
10-18 16:21:28.038: E/AndroidRuntime(3720): at dalvik.system.NativeStart.main(Native Method)
10-18 16:21:28.038: E/AndroidRuntime(3720): Caused by: java.lang.NullPointerException
10-18 16:21:28.038: E/AndroidRuntime(3720): at com.example.swipetabs.MainActivity.onTabSelected(MainActivity.java:67)
10-18 16:21:28.038: E/AndroidRuntime(3720): at com.android.internal.app.ActionBarImpl.selectTab(ActionBarImpl.java:577)
10-18 16:21:28.038: E/AndroidRuntime(3720): at com.android.internal.app.ActionBarImpl.addTab(ActionBarImpl.java:506)
10-18 16:21:28.038: E/AndroidRuntime(3720): at com.android.internal.app.ActionBarImpl.addTab(ActionBarImpl.java:492)
10-18 16:21:28.038: E/AndroidRuntime(3720): at com.example.swipetabs.MainActivity.onCreate(MainActivity.java:33)
10-18 16:21:28.038: E/AndroidRuntime(3720): at android.app.Activity.performCreate(Activity.java:5231)
10-18 16:21:28.038: E/AndroidRuntime(3720): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
10-18 16:21:28.038: E/AndroidRuntime(3720): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148)
10-18 16:21:28.038: E/AndroidRuntime(3720): ... 11 more
10-18 16:24:39.042: I/Adreno-EGL(3964): <qeglDrvAPI_eglInitialize:320>: EGL 1.4 QUALCOMM Build: I0404c4692afb8623f95c43aeb6d5e13ed4b30ddbDate: 11/06/13
10-18 16:24:39.072: D/OpenGLRenderer(3964): Enabling debug mode 0
10-18 16:24:49.854: D/dalvikvm(3964): GC_FOR_ALLOC freed 211K, 3% free 9287K/9528K, paused 17ms, total 17ms
10-18 16:29:09.851: I/Adreno-EGL(4899): <qeglDrvAPI_eglInitialize:320>: EGL 1.4 QUALCOMM Build: I0404c4692afb8623f95c43aeb6d5e13ed4b30ddbDate: 11/06/13
10-18 16:29:09.881: D/OpenGLRenderer(4899): Enabling debug mode 0
10-18 16:37:17.882: D/AndroidRuntime(5785): Shutting down VM
10-18 16:37:17.882: W/dalvikvm(5785): threadid=1: thread exiting with uncaught exception (group=0x41c18ba8)
10-18 16:37:17.882: E/AndroidRuntime(5785): FATAL EXCEPTION: main
10-18 16:37:17.882: E/AndroidRuntime(5785): Process: com.example.swipetabs, PID: 5785
10-18 16:37:17.882: E/AndroidRuntime(5785): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.swipetabs/com.example.swipetabs.MainActivity}: java.lang.NullPointerException
10-18 16:37:17.882: E/AndroidRuntime(5785): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2184)
10-18 16:37:17.882: E/AndroidRuntime(5785): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
10-18 16:37:17.882: E/AndroidRuntime(5785): at android.app.ActivityThread.access$800(ActivityThread.java:135)
10-18 16:37:17.882: E/AndroidRuntime(5785): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
10-18 16:37:17.882: E/AndroidRuntime(5785): at android.os.Handler.dispatchMessage(Handler.java:102)
10-18 16:37:17.882: E/AndroidRuntime(5785): at android.os.Looper.loop(Looper.java:136)
10-18 16:37:17.882: E/AndroidRuntime(5785): at android.app.ActivityThread.main(ActivityThread.java:5001)
10-18 16:37:17.882: E/AndroidRuntime(5785): at java.lang.reflect.Method.invokeNative(Native Method)
10-18 16:37:17.882: E/AndroidRuntime(5785): at java.lang.reflect.Method.invoke(Method.java:515)
10-18 16:37:17.882: E/AndroidRuntime(5785): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
10-18 16:37:17.882: E/AndroidRuntime(5785): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
10-18 16:37:17.882: E/AndroidRuntime(5785): at dalvik.system.NativeStart.main(Native Method)
10-18 16:37:17.882: E/AndroidRuntime(5785): Caused by: java.lang.NullPointerException
10-18 16:37:17.882: E/AndroidRuntime(5785): at com.example.swipetabs.MainActivity.onTabSelected(MainActivity.java:71)
10-18 16:37:17.882: E/AndroidRuntime(5785): at com.android.internal.app.ActionBarImpl.selectTab(ActionBarImpl.java:577)
10-18 16:37:17.882: E/AndroidRuntime(5785): at com.android.internal.app.ActionBarImpl.addTab(ActionBarImpl.java:506)
10-18 16:37:17.882: E/AndroidRuntime(5785): at com.android.internal.app.ActionBarImpl.addTab(ActionBarImpl.java:492)
10-18 16:37:17.882: E/AndroidRuntime(5785): at com.example.swipetabs.MainActivity.onCreate(MainActivity.java:36)
10-18 16:37:17.882: E/AndroidRuntime(5785): at android.app.Activity.performCreate(Activity.java:5231)
10-18 16:37:17.882: E/AndroidRuntime(5785): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
10-18 16:37:17.882: E/AndroidRuntime(5785): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148)
10-18 16:37:17.882: E/AndroidRuntime(5785): ... 11 more
提前致谢：）