Android：显示和隐藏片段

Question

我里面有一些Activity单全屏Fragment。在Fragment 里面，我有另一个Fragment 覆盖在屏幕的底部。所以在屏幕的顶部我有Button 控制内部Fragment 的可见/隐藏：

1. 包含Fragment的布局：

   ...
   <FrameLayout
       android:id="@+id/inner_fragment"
       android:layout_width="match_parent"
       android:layout_height="200dp"
       android:layout_below="@+id/top_part"
       android:name="com.package.InnerFragment" />
   

2. 控制Button：

   controlButton.setOnClickListener(new OnClickListener() {
       @Override
       public void onClick(View v) {
           if (!isInnerVisible) showHideInnerFragment("show");
           else showHideInnerFragment("hide");
       }
   });
   

3. 辅助方法showHideInnerFragment:

   private void showHideInnerFragment(String param) {
       //variables are class members...
       fragmentManager = getFragmentManager();
       fragmentTransaction = fragmentManager.beginTransaction();
       innerFragment = new InnerFragment();
       if (param.equals("show")) {
           fragmentTransaction.add(R.id.inner_fragment, innerFragment);
           isInnerVisible = true;
       } else {
           fragmentTransaction.remove(innerFragment);
           isInnerVisible = false;
       }
       fragmentTransaction.addToBackStack(null);
       fragmentTransaction.commit();
   }
   

嗯 - 这完全不工作......

Answer 1

您的 isInnerVisible 似乎始终为假（我假设它开始时为假），这会删​​除片段但保持 isInnerVisible 为假。您可能只需要切换它：

private void showHideInnerFragment(String param) {
    //variables are class members...
    fragmentManager = getFragmentManager();
    fragmentTransaction = fragmentManager.beginTransaction();
    innerFragment = new InnerFragment();
    if (param.equals("show")) {
        fragmentTransaction.add(R.id.inner_fragment, innerFragment);
        isInnerVisible = false;
    } else {
        fragmentTransaction.remove(innerFragment);
        isInnerVisible = true;
    }
    fragmentTransaction.addToBackStack(null);
    fragmentTransaction.commit();
}

我还会将真/假值传递给参数而不是字符串值，这样更容易理解代码在做什么，因为现在它有点没有意义。稍后我会更新一个示例；）

编辑：这是做你想做的更好的方法：

controlButton.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {
        showHideInnerFragment(isInnerVisible);
    }
});

---

private void showHideInnerFragment(boolean isVisible) {
    //variables are class members...
    fragmentManager = getFragmentManager();
    fragmentTransaction = fragmentManager.beginTransaction();
    innerFragment = new InnerFragment();
    if (isVisible == false) {
        fragmentTransaction.add(R.id.inner_fragment, innerFragment);
        isInnerVisible = true;
    } else {
        fragmentTransaction.remove(innerFragment);
        isInnerVisible = false;
    }
    fragmentTransaction.addToBackStack(null);
    fragmentTransaction.commit();
}