小编Nir*_*van的帖子

我已经查看了其他答案,但没有一个能帮助我.我确保使用import android.support.v4.app.Fragment;,这不是问题.

MainActivity.java

     package com.example.nirvan.fragmentsexample2;


    import android.support.v4.app.FragmentActivity;
    import android.support.v4.app.Fragment;
    import android.support.v4.app.FragmentTransaction;
    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;

    public class MainActivity extends FragmentActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        myFragment myfragment=new myFragment();
        FragmentTransaction fragmentTransaction=getSupportFragmentManager().beginTransaction();
        fragmentTransaction.add(R.id.fragmentContainer,myfragment);
        fragmentTransaction.commit();

    }
   }

错误:

Error:(20, 28) error: no suitable method found for add(int,myFragment)
method FragmentTransaction.add(Fragment,String) is not applicable
(argument mismatch; int cannot be converted to Fragment)
method FragmentTransaction.add(int,Fragment) is not applicable
(argument mismatch; myFragment cannot be converted to Fragment)

我为什么要这个？

在activity_main.xml中 …