我不知道是什么让我的应用停止了

Question

• 我正在用actionbar中的Tab使用片段制作我的应用程序。我的代码如下：

- Tab1Fragment.java & Tab2Fragment is the same 

公共类Tab1Fragment扩展了ListFragment{ String list[] = new String[]{ "apple“、"bluecherry”、"cherry“、"coconut”}；(非Javadoc)*@见android.app.ListFragment#onCreateView(android.view.LayoutInflater，android.view.ViewGroup，android.os.Bundle) */ @Nullable @重写公共视图onCreateView(LayoutInflater inflater，@Nullable ViewGroup容器，Bundle savedInstanceState) { // TODO自动生成的方法存根视图视图= inflater.inflate(R.layout.tablist，容器，false)；ListAdapter适配器=新ArrayAdapter(getActivity()，android.R.layout.simple_list_item_1，list)；setListAdapter(适配器)；返回视图；}@覆盖公共onListItemClick(ListView l，View v，int位置，long id) { Toast.makeText(getActivity()，"Vịtrívừa chọn：“+Toast.makeText+，”+ "vớiội dung“+ Toast.LENGTH_SHORT).show()；}

- Main Activity: 

​

​

public class MainActivity extends FragmentActivity implements ActionBar.TabListener {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        final ActionBar ab = getActionBar();
        ab.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
        ab.addTab(ab.newTab().setText("List").setTabListener(this));
        ab.addTab(ab.newTab().setText("Custom").setTabListener(this));
    }

    @Override
    public void onTabSelected(ActionBar.Tab tab, FragmentTransaction ft) {
        if(tab.getPosition()==0){
            Tab1Fragment tab1 = new Tab1Fragment();
            getFragmentManager().beginTransaction().replace(R.id.container, tab1).commit();
        } else if(tab.getPosition()==1){
            Tab2Fragment tab2 = new Tab2Fragment();
            getFragmentManager().beginTransaction().replace(R.id.container,tab2).commit();
        }
    }

    @Override
    public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {

    }

    @Override
    public void onTabReselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {

    }
}

​

• 我的main_activity.xml：

​

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >
</RelativeLayout>

​

• tablist.xml和tabcustom.xml是相同的：

​

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    <ListView
        android:id="@id/android:list"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >
    </ListView>
</LinearLayout>

​

我的应用程序的目标是API14:Android4.0(IceCreamSandwich)。我已经发现了3天，不明白为什么这个应用程序停止时，它开始。

• LogCat错误：

​

11-26 14:23:01.544 3417-3417/? E/libprocessgroup: failed to make and chown /acct/uid_10068: Read-only file system
11-26 14:23:01.544 3417-3417/? W/Zygote: createProcessGroup failed, kernel missing CONFIG_CGROUP_CPUACCT?
11-26 14:23:01.545 3417-3417/? I/art: Late-enabling -Xcheck:jni
11-26 14:23:01.692 3417-3417/com.example.hoang.b13 W/art: Failed execv(/system/bin/dex2oat --runtime-arg -classpath --runtime-arg  --debuggable --instruction-set=x86 --instruction-set-features=smp,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 --runtime-arg -Xrelocate --boot-image=/system/framework/boot.art --runtime-arg -Xms64m --runtime-arg -Xmx512m --instruction-set-variant=x86 --instruction-set-features=default --dex-file=/data/app/com.example.hoang.b13-1/split_lib_dependencies_apk.apk --oat-file=/data/dalvik-cache/x86/data@app@com.example.hoang.b13-1@split_lib_dependencies_apk.apk@classes.dex) because non-0 exit status
11-26 14:23:02.053 3417-3417/com.example.hoang.b13 W/art: Failed execv(/system/bin/dex2oat --runtime-arg -classpath --runtime-arg  --debuggable --instruction-set=x86 --instruction-set-features=smp,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 --runtime-arg -Xrelocate --boot-image=/system/framework/boot.art --runtime-arg -Xms64m --runtime-arg -Xmx512m --instruction-set-variant=x86 --instruction-set-features=default --dex-file=/data/app/com.example.hoang.b13-1/split_lib_slice_0_apk.apk --oat-file=/data/dalvik-cache/x86/data@app@com.example.hoang.b13-1@split_lib_slice_0_apk.apk@classes.dex) because non-0 exit status
11-26 14:23:02.089 3417-3417/com.example.hoang.b13 W/art: Failed execv(/system/bin/dex2oat --runtime-arg -classpath --runtime-arg  --debuggable --instruction-set=x86 --instruction-set-features=smp,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 --runtime-arg -Xrelocate --boot-image=/system/framework/boot.art --runtime-arg -Xms64m --runtime-arg -Xmx512m --instruction-set-variant=x86 --instruction-set-features=default --dex-file=/data/app/com.example.hoang.b13-1/split_lib_slice_1_apk.apk --oat-file=/data/dalvik-cache/x86/data@app@com.example.hoang.b13-1@split_lib_slice_1_apk.apk@classes.dex) because non-0 exit status
11-26 14:23:02.111 3417-3417/com.example.hoang.b13 W/art: Failed execv(/system/bin/dex2oat --runtime-arg -classpath --runtime-arg  --debuggable --instruction-set=x86 --instruction-set-features=smp,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 --runtime-arg -Xrelocate --boot-image=/system/framework/boot.art --runtime-arg -Xms64m --runtime-arg -Xmx512m --instruction-set-variant=x86 --instruction-set-features=default --dex-file=/data/app/com.example.hoang.b13-1/split_lib_slice_2_apk.apk --oat-file=/data/dalvik-cache/x86/data@app@com.example.hoang.b13-1@split_lib_slice_2_apk.apk@classes.dex) because non-0 exit status
11-26 14:23:02.132 3417-3417/com.example.hoang.b13 W/art: Failed execv(/system/bin/dex2oat --runtime-arg -classpath --runtime-arg  --debuggable --instruction-set=x86 --instruction-set-features=smp,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 --runtime-arg -Xrelocate --boot-image=/system/framework/boot.art --runtime-arg -Xms64m --runtime-arg -Xmx512m --instruction-set-variant=x86 --instruction-set-features=default --dex-file=/data/app/com.example.hoang.b13-1/split_lib_slice_3_apk.apk --oat-file=/data/dalvik-cache/x86/data@app@com.example.hoang.b13-1@split_lib_slice_3_apk.apk@classes.dex) because non-0 exit status
11-26 14:23:02.149 3417-3417/com.example.hoang.b13 W/art: Failed execv(/system/bin/dex2oat --runtime-arg -classpath --runtime-arg  --debuggable --instruction-set=x86 --instruction-set-features=smp,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 --runtime-arg -Xrelocate --boot-image=/system/framework/boot.art --runtime-arg -Xms64m --runtime-arg -Xmx512m --instruction-set-variant=x86 --instruction-set-features=default --dex-file=/data/app/com.example.hoang.b13-1/split_lib_slice_4_apk.apk --oat-file=/data/dalvik-cache/x86/data@app@com.example.hoang.b13-1@split_lib_slice_4_apk.apk@classes.dex) because non-0 exit status
11-26 14:23:02.166 3417-3417/com.example.hoang.b13 W/art: Failed execv(/system/bin/dex2oat --runtime-arg -classpath --runtime-arg  --debuggable --instruction-set=x86 --instruction-set-features=smp,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 --runtime-arg -Xrelocate --boot-image=/system/framework/boot.art --runtime-arg -Xms64m --runtime-arg -Xmx512m --instruction-set-variant=x86 --instruction-set-features=default --dex-file=/data/app/com.example.hoang.b13-1/split_lib_slice_5_apk.apk --oat-file=/data/dalvik-cache/x86/data@app@com.example.hoang.b13-1@split_lib_slice_5_apk.apk@classes.dex) because non-0 exit status
11-26 14:23:02.182 3417-3417/com.example.hoang.b13 W/art: Failed execv(/system/bin/dex2oat --runtime-arg -classpath --runtime-arg  --debuggable --instruction-set=x86 --instruction-set-features=smp,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 --runtime-arg -Xrelocate --boot-image=/system/framework/boot.art --runtime-arg -Xms64m --runtime-arg -Xmx512m --instruction-set-variant=x86 --instruction-set-features=default --dex-file=/data/app/com.example.hoang.b13-1/split_lib_slice_6_apk.apk --oat-file=/data/dalvik-cache/x86/data@app@com.example.hoang.b13-1@split_lib_slice_6_apk.apk@classes.dex) because non-0 exit status
11-26 14:23:02.199 3417-3417/com.example.hoang.b13 W/art: Failed execv(/system/bin/dex2oat --runtime-arg -classpath --runtime-arg  --debuggable --instruction-set=x86 --instruction-set-features=smp,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 --runtime-arg -Xrelocate --boot-image=/system/framework/boot.art --runtime-arg -Xms64m --runtime-arg -Xmx512m --instruction-set-variant=x86 --instruction-set-features=default --dex-file=/data/app/com.example.hoang.b13-1/split_lib_slice_7_apk.apk --oat-file=/data/dalvik-cache/x86/data@app@com.example.hoang.b13-1@split_lib_slice_7_apk.apk@classes.dex) because non-0 exit status
11-26 14:23:02.215 3417-3417/com.example.hoang.b13 W/art: Failed execv(/system/bin/dex2oat --runtime-arg -classpath --runtime-arg  --debuggable --instruction-set=x86 --instruction-set-features=smp,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 --runtime-arg -Xrelocate --boot-image=/system/framework/boot.art --runtime-arg -Xms64m --runtime-arg -Xmx512m --instruction-set-variant=x86 --instruction-set-features=default --dex-file=/data/app/com.example.hoang.b13-1/split_lib_slice_8_apk.apk --oat-file=/data/dalvik-cache/x86/data@app@com.example.hoang.b13-1@split_lib_slice_8_apk.apk@classes.dex) because non-0 exit status
11-26 14:23:02.232 3417-3417/com.example.hoang.b13 W/art: Failed execv(/system/bin/dex2oat --runtime-arg -classpath --runtime-arg  --debuggable --instruction-set=x86 --instruction-set-features=smp,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 --runtime-arg -Xrelocate --boot-image=/system/framework/boot.art --runtime-arg -Xms64m --runtime-arg -Xmx512m --instruction-set-variant=x86 --instruction-set-features=default --dex-file=/data/app/com.example.hoang.b13-1/split_lib_slice_9_apk.apk --oat-file=/data/dalvik-cache/x86/data@app@com.example.hoang.b13-1@split_lib_slice_9_apk.apk@classes.dex) because non-0 exit status
11-26 14:23:02.233 3417-3417/com.example.hoang.b13 W/System: ClassLoader referenced unknown path: /data/app/com.example.hoang.b13-1/lib/x86
11-26 14:23:02.235 3417-3417/com.example.hoang.b13 I/InstantRun: starting instant run server: is main process
11-26 14:23:02.271 3417-3417/com.example.hoang.b13 D/AndroidRuntime: Shutting down VM
11-26 14:23:02.272 3417-3417/com.example.hoang.b13 E/AndroidRuntime: FATAL EXCEPTION: main
                                                                     Process: com.example.hoang.b13, PID: 3417
                                                                     java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.hoang.b13/com.example.hoang.b13.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.app.ActionBar.setNavigationMode(int)' on a null object reference
                                                                         at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
                                                                         at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
                                                                         at android.app.ActivityThread.-wrap11(ActivityThread.java)
                                                                         at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
                                                                         at android.os.Handler.dispatchMessage(Handler.java:102)
                                                                         at android.os.Looper.loop(Looper.java:148)
                                                                         at android.app.ActivityThread.main(ActivityThread.java:5417)
                                                                         at java.lang.reflect.Method.invoke(Native Method)
                                                                         at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
                                                                         at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
                                                                      Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.app.ActionBar.setNavigationMode(int)' on a null object reference
                                                                         at com.example.hoang.b13.MainActivity.onCreate(MainActivity.java:16)
                                                                         at android.app.Activity.performCreate(Activity.java:6237)
                                                                         at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
                                                                         at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369)
                                                                         at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) 
                                                                         at android.app.ActivityThread.-wrap11(ActivityThread.java) 
                                                                         at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344) 
                                                                         at android.os.Handler.dispatchMessage(Handler.java:102) 
                                                                         at android.os.Looper.loop(Looper.java:148) 
                                                                         at android.app.ActivityThread.main(ActivityThread.java:5417) 
                                                                         at java.lang.reflect.Method.invoke(Native Method) 
                                                                         at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 
                                                                         at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 
11-26 14:23:03.996 3417-3417/? I/Process: Sending signal. PID: 3417 SIG: 9

​

Answer 1

您必须扩展ActionBarActivity而不是FragmentActivity，才能使Actionbar具有片段。

仍然试图在下面的代码

ActionBar actionBar = (ActionBarActivity)getActivity().getSupportActionBar();

更多细节请参见此http://developer.android.com/training/basics/fragments/creating.html