从Fragment中的按钮跳转至另一个页面的问题

求解我显示编辑了一个Fragment的类，代码如下：

import android.app.Activity;
import android.app.Fragment;
import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.ListView;
public class FragmentRecord extends Fragment implements View.OnClickListener{
private ListView listView;
private String[] mStrings = {"运动1", "运动2", "运动3"};
private ArrayAdapterarray_adapter;
private ImageView btn_add;
@Override
public void onAttach(Activity activity) {
    // TODO Auto-generated method stub
    super.onAttach(activity);
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    View rootView =inflater.inflate(R.layout.fragment_record, container, false);
    listView = (ListView)rootView.findViewById(R.id.listView_data);//获取自己视图里的控件引用
    btn_add=(ImageView) rootView.findViewById(R.id.btn_add);
    //return inflater.inflate(R.layout.fragment_record,container,false);
    return rootView;  
    }

@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onActivityCreated(savedInstanceState);
    array_adapter = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, mStrings);
    listView.setAdapter(array_adapter);
    btn_add=(ImageView) getActivity().findViewById(R.id.btn_add);
    btn_add.setOnClickListener(this);

}

@Override
public void onClick(View v) {
    // TODO Auto-generated method stub
    Intent  intent =new Intent(getActivity(),FragmentTarget.class);
    FragmentRecord.this.startActivity(intent);
}
}

我设置了按钮的点击事件，可是为什么一点按钮就报错，错误如下：、
图片说明

然后我想要跳转的页面是这样的一个：

import android.app.Activity;
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class FragmentTarget extends Fragment {
@Override
public void onAttach(Activity activity) {
// TODO Auto-generated method stub
super.onAttach(activity);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_target, container, false);
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onActivityCreated(savedInstanceState);
}
}

不太清楚如何改可以改了这个FragmentTartget强制转换成activity的错误