android - 无法转换为 Fragment

Question

我创建了一个 FragmentOne extends Fragment，但出现以下编译时错误:

"cannot be converted to Fragment!",

我正在关注这个tutorial

public class MainActivity extends AppCompatActivity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
  }
  public void selectFrag(View view){
      Fragment fragment;
      if(view == findViewById(R.id.button1)){
          fragment = new FragmentOne();
      }
  }
} 

Answer 1

您正在使用 AppcompatActivity 。所以将您的 fragment 导入替换为

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;

代替

import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;