frament点击按钮跳到activity程序停止运行

package textview.exam;

import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;

public class FragmentMe extends Fragment {
Button loginbutton;

@Override
public void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);


}

@Override
public View onCreateView(LayoutInflater inflater,
                         @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    View view = inflater.inflate(R.layout.me, container,false);
    loginbutton=(Button)view.findViewById(R.id.login);
    loginbutton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent intent = new Intent(getActivity(), LoginActivity.class);
            startActivity(intent);
        }
    });
    return view;

}

}
在MainActivity或者能够要写什么嘛

报错的Log 贴上来看看

activity
你配置了吗？

05-30 09:18:20.981 1281-1281/textview.exam E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: textview.exam, PID: 1281
java.lang.RuntimeException: Unable to start activity ComponentInfo{textview.exam/textview.exam.LoginActivity}: java.lang.IllegalArgumentException: No view found for id 0x7f0a0056 (textview.exam:id/main_content) for fragment FragmentChat{3c22b47c #0 id=0x7f0a0056}
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
at android.app.ActivityThread.access$800(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
Caused by: java.lang.IllegalArgumentException: No view found for id 0x7f0a0056 (textview.exam:id/main_content) for fragment FragmentChat{3c22b47c #0 id=0x7f0a0056}
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:939)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1126)
at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:739)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1489)
at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:548)
at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1220)
at android.app.Activity.performStart(Activity.java:5949)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2261)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
            at android.app.ActivityThread.access$800(ActivityThread.java:144)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5221)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)

这是报错，大神们看看哪里错了。。。

id/main_content 在什么xml文件中？
LoginActivity.java 的onCreate（）
中是否有
setContentView(R.layout.Your_layout_file);
Your_layout_file.xml是否有id/main_content ？

如果还有问题，请将LoginActivity.java 代码贴上来