片段无法转换为Context

Question

这是我第一次使用片段(android dev的新手),我正在尝试设置一个微调器.目前我对上下文很困惑,似乎无法解决这个错误:

Error:(52, 78) error: incompatible types: HotkeysFragment cannot be converted to Context

这是它所指的代码:

HotkeysFragment.java

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    if (getArguments() != null) {
        mParam1 = getArguments().getString(ARG_PARAM1);
        mParam2 = getArguments().getString(ARG_PARAM2);
    }

    Spinner hotkey_selector_spinner = (Spinner) rootView.findViewById(R.id.hotkey_selector_spinner);

    ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
            R.array.hotkey_options, android.R.layout.simple_spinner_item);
    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    hotkey_selector_spinner.setAdapter(adapter);
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    final View rootViewB = inflater.inflate(R.layout.fragment_hotkeys, container, false);
    rootView = rootViewB;
    return rootViewB;
}

具体路线是:

ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
            R.array.hotkey_options, android.R.layout.simple_spinner_item);

进口:

import android.app.Activity; 
import android.net.Uri;
import android.os.Bundle;
import android.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import java.util.zip.Inflater;

我怎样才能解决这个问题？

Answer 1

来自此处的片段Android文档:

警告:如果在Fragment中需要Context对象,则可以调用getActivity().但是,只有在片段附加到活动时才要小心调用getActivity().当片段尚未附加或在其生命周期结束时被分离时,getActivity()将返回null.

因此,除了改变this到getActivity(),我也建议你一起工作getActivity()的onActivityCreated()(因为你还需要以膨胀第一)

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);
    if (getArguments() != null) {
        mParam1 = getArguments().getString(ARG_PARAM1);
        mParam2 = getArguments().getString(ARG_PARAM2);
    }

    Spinner hotkey_selector_spinner = (Spinner) getView().findViewById(R.id.hotkey_selector_spinner);

    ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(getActivity(),
            R.array.hotkey_options, android.R.layout.simple_spinner_item);
    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    hotkey_selector_spinner.setAdapter(adapter);
}