google提供了Android Support Library package 系列的包来保证来高版本sdk开发的向下兼容性,即我们用4.x开发时,在1.6等版本上,可以使用高版本的有些特性,如Fragement,ViewPager等,下面,简单说明下这几个版本间的区别: Android Support v4: 这个包是为了照顾1.6及更高版本而设计的,这个包是使用最广泛的,eclipse新建工程时,都默认带有了。 Android Support v7: 这个包是为了考虑照顾2.1及以上版本而设计的,但不包含更低,故如果不考虑1.6,我们可以采用再加上这个包,另外注意,v7是要依赖v4这个包的,即,两个得同时被包含。 Android Support v13 :这个包的设计是为了android 3.2及更高版本的,一般我们都不常用,平板开发中能用到。貌似 没有影响的 这两个
http://download.csdn.net/download/jingshuaizh/8207711
出错信息
11-29 17:44:53.925: D/jdwp(30233): sendBufferedRequest : len=0x45
11-29 17:44:53.927: W/asset(30233): AssetManager-->addDefaultAssets CIP path not exsit!
11-29 17:44:53.949: D/dalvikvm(30233): open_cached_dex_file : /data/app/com.example.viewpager-1.apk /data/dalvik-cache/data@[email protected]@classes.dex
11-29 17:44:54.168: D/AndroidRuntime(30233): Shutting down VM
11-29 17:44:54.168: W/dalvikvm(30233): threadid=1: thread exiting with uncaught exception (group=0x40e2b978)
11-29 17:44:54.168: W/dalvikvm(30233): threadid=1: uncaught exception occurred
11-29 17:44:54.169: W/System.err(30233): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.viewpager/com.example.viewpager.MainActivity}: java.lang.NullPointerException
11-29 17:44:54.169: W/System.err(30233): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2372)
11-29 17:44:54.169: W/System.err(30233): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2424)
11-29 17:44:54.169: W/System.err(30233): at android.app.ActivityThread.access$600(ActivityThread.java:169)
11-29 17:44:54.170: W/System.err(30233): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1388)
11-29 17:44:54.170: W/System.err(30233): at android.os.Handler.dispatchMessage(Handler.java:107)
11-29 17:44:54.170: W/System.err(30233): at android.os.Looper.loop(Looper.java:194)
11-29 17:44:54.170: W/System.err(30233): at android.app.ActivityThread.main(ActivityThread.java:5433)
11-29 17:44:54.170: W/System.err(30233): at java.lang.reflect.Method.invokeNative(Native Method)
11-29 17:44:54.170: W/System.err(30233): at java.lang.reflect.Method.invoke(Method.java:525)
11-29 17:44:54.171: W/System.err(30233): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:922)
11-29 17:44:54.171: W/System.err(30233): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:689)
11-29 17:44:54.171: W/System.err(30233): at dalvik.system.NativeStart.main(Native Method)
11-29 17:44:54.171: W/System.err(30233): Caused by: java.lang.NullPointerException
11-29 17:44:54.172: W/System.err(30233): at com.example.viewpager.MainActivity.onCreate(MainActivity.java:29)
11-29 17:44:54.172: W/System.err(30233): at android.app.Activity.performCreate(Activity.java:5211)
11-29 17:44:54.172: W/System.err(30233): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1146)
11-29 17:44:54.172: W/System.err(30233): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2336)
11-29 17:44:54.172: W/System.err(30233): ... 11 more
11-29 17:44:54.172: W/dalvikvm(30233): threadid=1: calling UncaughtExceptionHandler
11-29 17:44:54.174: E/AndroidRuntime(30233): FATAL EXCEPTION: main
11-29 17:44:54.174: E/AndroidRuntime(30233): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.viewpager/com.example.viewpager.MainActivity}: java.lang.NullPointerException
11-29 17:44:54.174: E/AndroidRuntime(30233): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2372)
11-29 17:44:54.174: E/AndroidRuntime(30233): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2424)
11-29 17:44:54.174: E/AndroidRuntime(30233): at android.app.ActivityThread.access$600(ActivityThread.java:169)
11-29 17:44:54.174: E/AndroidRuntime(30233): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1388)
11-29 17:44:54.174: E/AndroidRuntime(30233): at android.os.Handler.dispatchMessage(Handler.java:107)
11-29 17:44:54.174: E/AndroidRuntime(30233): at android.os.Looper.loop(Looper.java:194)
11-29 17:44:54.174: E/AndroidRuntime(30233): at android.app.ActivityThread.main(ActivityThread.java:5433)
11-29 17:44:54.174: E/AndroidRuntime(30233): at java.lang.reflect.Method.invokeNative(Native Method)
11-29 17:44:54.174: E/AndroidRuntime(30233): at java.lang.reflect.Method.invoke(Method.java:525)
11-29 17:44:54.174: E/AndroidRuntime(30233): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:922)
11-29 17:44:54.174: E/AndroidRuntime(30233): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:689)
11-29 17:44:54.174: E/AndroidRuntime(30233): at dalvik.system.NativeStart.main(Native Method)
11-29 17:44:54.174: E/AndroidRuntime(30233): Caused by: java.lang.NullPointerException
11-29 17:44:54.174: E/AndroidRuntime(30233): at com.example.viewpager.MainActivity.onCreate(MainActivity.java:29)
11-29 17:44:54.174: E/AndroidRuntime(30233): at android.app.Activity.performCreate(Activity.java:5211)
11-29 17:44:54.174: E/AndroidRuntime(30233): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1146)
11-29 17:44:54.174: E/AndroidRuntime(30233): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2336)
11-29 17:44:54.174: E/AndroidRuntime(30233): ... 11 more
在gen文件夹里是v7的,但是libs里用的又是v4的jar
Android Support v4: 这个包是为了照顾1.6及更高版本而设计的,这个包是使用最广泛的,eclipse新建工程时,都默认带有了。
Android Support v7: 这个包是为了考虑照顾2.1及以上版本而设计的,但不包含更低,故如果不考虑1.6,我们可以采用再加上这个包,另外注意,v7是要依赖v4这个包的,即,两个得同时被包含。
Android Support v13 :这个包的设计是为了android 3.2及更高版本的,一般我们都不常用,平板开发中能用到。貌似 没有影响的 这两个