Question

我正在尝试通过一个教程，并遇到了一些障碍。教程实现一个SingleFragmentActivity类来托管一个片段（xml文件与它一起使用。

我的问题是在这个SingleFragmentActivity.java类中，有一个调用setContentView（int）抛出一个错误，它说它无法找到该方法。是不是setContentView（int）是Fragment Class的一部分？

import android.app.Fragment;

import android.app.FragmentManager; import android.os.Bundle;

public abstract class SingleFragmentActivity extends Fragment {
   protected abstract Fragment createFragment();

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_fragment);

    FragmentManager manager = getFragmentManager();
    Fragment fragment = manager.findFragmentById(R.id.fragmentContainer);

    if (fragment == null) {
        fragment = createFragment();
        manager.beginTransaction()
            .add(R.id.fragmentContainer, fragment)
            .commit();
    }
  }
}

Answer 1

.app.Fragment在onCreateView中初始化了其视图。基本上，您需要使用inflater来扩展您的视图并将其作为onCreateView中的根视图返回。

Reference

链接中的示例

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    if (container == null) {
        // We have different layouts, and in one of them this
        // fragment's containing frame doesn't exist.  The fragment
        // may still be created from its saved state, but there is
        // no reason to try to create its view hierarchy because it
        // won't be displayed.  Note this is not needed -- we could
        // just run the code below, where we would create and return
        // the view hierarchy; it would just never be used.
        return null;
    }

    ScrollView scroller = new ScrollView(getActivity());
    TextView text = new TextView(getActivity());
    int padding = (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
            4, getActivity().getResources().getDisplayMetrics());
    text.setPadding(padding, padding, padding, padding);
    scroller.addView(text);
    text.setText(Shakespeare.DIALOGUE[getShownIndex()]);
    return scroller;
}

此外，如果您想使用setContentView，请在支持库中使用FragmentActivity。

Answer 2

你做错了。 setContentView（int）适用于Activity，但您的类正在扩展Fragment，因此您需要对xml进行膨胀并返回onCreateView

中的视图

这是例如：

@Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout. activity_fragment, container, false);
        // Do some Initialization
        return view;
    }

还有一点，请不要使用Activity命名您的片段类。它会让你感到困惑：）

Answer 3

setContentView不是Fragment的成员。要为片段充气，您需要在充气后将视图返回到onCreateView：

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    return inflater.inflate(R.layout.fragment_layout, container, false);
}

setContentView（int）不起作用

3 个答案: