Question

如何投射片段活动？

实际上我正试图通过活动上的按钮打开片段活动

Android MainFest：

<activity android:name="parth.any.ttb.Fragment_1"/>

logcat的：

12-04 15:22:43.132: E/AndroidRuntime(25873): FATAL EXCEPTION: main
12-04 15:22:43.132: E/AndroidRuntime(25873): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{parth.any.ttb/parth.any.ttb.Fragment_1}: java.lang.ClassCastException: parth.any.ttb.Fragment_1
12-04 15:22:43.132: E/AndroidRuntime(25873):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1573)
12-04 15:22:43.132: E/AndroidRuntime(25873):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
12-04 15:22:43.132: E/AndroidRuntime(25873):    at android.app.ActivityThread.access$1500(ActivityThread.java:117)
12-04 15:22:43.132: E/AndroidRuntime(25873):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
12-04 15:22:43.132: E/AndroidRuntime(25873):    at android.os.Handler.dispatchMessage(Handler.java:99)
12-04 15:22:43.132: E/AndroidRuntime(25873):    at android.os.Looper.loop(Looper.java:130)
12-04 15:22:43.132: E/AndroidRuntime(25873):    at android.app.ActivityThread.main(ActivityThread.java:3687)
12-04 15:22:43.132: E/AndroidRuntime(25873):    at java.lang.reflect.Method.invokeNative(Native Method)
12-04 15:22:43.132: E/AndroidRuntime(25873):    at java.lang.reflect.Method.invoke(Method.java:507)
12-04 15:22:43.132: E/AndroidRuntime(25873):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
12-04 15:22:43.132: E/AndroidRuntime(25873):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
12-04 15:22:43.132: E/AndroidRuntime(25873):    at dalvik.system.NativeStart.main(Native Method)
12-04 15:22:43.132: E/AndroidRuntime(25873): Caused by: java.lang.ClassCastException: parth.any.ttb.Fragment_1
12-04 15:22:43.132: E/AndroidRuntime(25873):    at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
12-04 15:22:43.132: E/AndroidRuntime(25873):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1565

）

以下是两个类代码： 编辑：NewTransaction.java

startActivity(new Intent(getApplicationContext(), Fragment_1.class));

Fragment_1.java

public class Fragment_1 extends Fragment implements OnClickListener {
        TextView Home;
        Animation animMove;

        // slide menu items
        private String[] spinMenuTitles;
        private TypedArray spinMenuIcons;
        private Button Add_New;     
        private ArrayList<TypeCustomSpinnerItem> spinDropItems;
        private TypeSpinnerListAdapter adapter;

    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
        View view = inflater.inflate(R.layout.fragment_1, null);
        Home = (TextView)view.findViewById(R.id.home);
        Add_New = (Button)view.findViewById(R.id.add_new);
        Add_New.setOnClickListener(this);

        animMove = AnimationUtils.loadAnimation(getActivity(),R.anim.move);
        Home.startAnimation(animMove);

                // load type spin menu items
                spinMenuTitles = getResources().getStringArray(R.array.type_spinner_items);

                // type spinner icons from resources
                spinMenuIcons = getResources().obtainTypedArray(R.array.type_spinner_icons);

                spinDropItems = new ArrayList<TypeCustomSpinnerItem>();

                // adding type spinner items to array
                int i;
                for(i=0;i<=9;i++)
                {
                spinDropItems.add(new TypeCustomSpinnerItem(spinMenuTitles[i], spinMenuIcons.getResourceId(i, -1)));
                }
                // Recycle the typed array
                spinMenuIcons.recycle();

                Spinner mySpinner = (Spinner)view.findViewById(R.id.spinner1);
                adapter = new TypeSpinnerListAdapter(getActivity(),spinDropItems);
                mySpinner.setAdapter(adapter);

        return view;
    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        switch (v.getId()) {
        case R.id.add_new:
            Intent addintent = new Intent(getActivity() , AddNewTransaction.class);
            startActivity(addintent);
            break;

    }
    }
}

Answer 1

您无法将片段作为活动启动，需要将它们添加到活动中。

在文档here中阅读更多内容。

另请参阅this

Answer 2

Frament_1是一个片段

 public class Fragment_1 extends Fragment implements OnClickListener {

您不能将startActivity用于片段。 Fragment由活动托管。

在您的活动布局中，xml具有以下内容。

以编程方式将片段添加到现有ViewGroup。

<FrameLayout
android:id="@+id/content_frame"
android:layout_width="match_parent"
android:layout_height="match_parent" />

FrameLayout是容器。您正在向容器添加片段。

活动

 FragmentTransaction fragTran = getSupportFragmentManager().beginTransaction();
 Fragment_1  fragment1 = new Fragment_1()
 fragTran.replace(R.id.content_frame, fragment1);

您也可以在xml中使用以下内容。在活动的布局文件中声明片段。

 <fragment android:name="com.example.fragment.Fragment_1"
 android:id="@+id/list"
 android:layout_width="match_parent"
 android:layout_height="match_parent" />

了解更多信息

http://developer.android.com/guide/components/fragments.html

片段java.lang.ClassCastException错误

2 个答案: