同时Fragment的View也会被detach。在重新调用attach()后，onCreateView()-onResume()周期也会被再次执行。
remove()
其实看完上面的分析，remove()方法基本也就明白了。相对应add()方法执行onAttach()-onResume()的生命周期，remove()就是完成剩下的onPause()-onDetach()周期。
错误
曾经在FragmentTransaction编写时遇到过以下错误：
复制代码The method replace(int, Fragment) in the type FragmentTransaction is not applicable for the arguments (int, MyFragment)
Fragment newfragment =new MyFragment();
fragmentTransaction.replace(R.layout.activity_main,newfragment ).commit();
提示错误：The method replace(int, Fragment) in the type FragmentTransaction is not applicable for the arguments (int, MyFragment)
原因找了好久！一直以为子类对象不能赋值给父类引用。这不科学啊！
代码时这样的：
package com.example.testforfragment;
import android.os.Bundle;
import android.app.Activity;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.support.v4.app.Fragment;
import android.support.v4.app.Fragment.*;
import android.view.Menu;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
Fragment newfragment =new MyFragment();
fragmentTransaction.replace(R.layout.activity_main,newfragment ).commit();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
