用另一个片段替换片段，并删除视图

Question

我有一个活动和两个片段。片断a和片断b。

我需要实现像，最初碎片应该在那里。在按钮之后，单击FragmentB应该在那里。

public class FragmentActivity extends AppCompatActivity {

FrameLayout activityFragment;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_fragment);
    activityFragment = (FrameLayout) findViewById(R.id.activityFragment);
    Fragment fragment = new FragmentA();
    FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
    transaction.add(R.id.activityFragment, fragment);
    transaction.commit();
}

public void goToFrag(View view) {
    FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
    Fragment fragment = new FragmentB();
    transaction.add(R.id.fragmentRoot, fragment);
    transaction.commit();
}
}

  public class FragmentA extends Fragment {

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    super.onCreateView(inflater, container, savedInstanceState);
    View view=inflater.inflate(R.layout.fragment_a,container,false);
    return view;
}
}

我的第二段代码：

   public class FragmentB extends Fragment {
public FragmentB() {
}

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
     super.onCreateView(inflater, container, savedInstanceState);
    View view=inflater.inflate(R.layout.fragment_b,container,false);
    return view;
}
}

Answer 1

首先，您应该始终在xml中使用FrameLayout来替换片段，然后使用不同的容器来添加片段ActivityFragment和FragmentRoot。对于FragmentManager，您可以使用Add或Replace，因此ActivityFragment是您使用的容器（正如文档建议的那样，它应该是作为包装器的framelayout）

public void goToFrag(View view) {
    FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
    Fragment fragment = new FragmentB();
    transaction.replace(R.id.activityFragment, fragment); // use the same container where you switch A and B
    transaction.commit();
}