Android的getApplicationContext()错误 [英] getApplicationContext() error Android

问题描述

我有一个片段，允许用户输入消息以及将消息传递到的电话号码.我收到一个错误无法解析方法getApplicationContext()"，我在这里查看了答案该方法getApplicationContext()是未定义的，但是它没有帮助我，也许我实现错误，但是我不确定！此代码可以很好地用作活动，但不能作为片段.

I have a fragment that allows a user to enter in a message and a phone number to which the message will be delivered. I am getting an error "cannot resolve method getApplicationContext()" I have looked at the answer here the method getApplicationContext() is undefined but it didn't help me, maybe I am implementing it wrong but I am not sure! This code works fine as an activity but not as a fragment.

FragmentTab1类

package com.androidbegin.absfragtabhost;

import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.app.Fragment;
import android.app.Activity;
import android.telephony.SmsManager;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class FragmentTab3 extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    View rootView = inflater.inflate(R.layout.fragmenttab3, container, false);
    super.onCreate(savedInstanceState);
    //setContentView(R.layout.activity_main);

    sendBtn = (Button) rootView.findViewById(R.id.btnSendSMS);
    txtphoneNo = (EditText) rootView.findViewById(R.id.editTextPhoneNo);
    txtMessage = (EditText) rootView.findViewById(R.id.editTextSMS);

    sendBtn.setOnClickListener(new View.OnClickListener() {
        public void onClick(View view) {
            sendSMSMessage();
        }
    });

    return rootView;
}



    Button sendBtn;
    EditText txtphoneNo;
    EditText txtMessage;



    protected void sendSMSMessage() {
        Log.i("Send SMS", "");

        String phoneNo = txtphoneNo.getText().toString();
        String message = txtMessage.getText().toString();

        try {
            SmsManager smsManager = SmsManager.getDefault();
            smsManager.sendTextMessage(phoneNo, null, message, null, null);
            Toast.makeText(getApplicationContext(), "SMS sent.",
                    Toast.LENGTH_LONG).show();
        } catch (Exception e) {
            Toast.makeText(getApplicationContext(),
                    "SMS failed, please try again.",
                    Toast.LENGTH_LONG).show();
            e.printStackTrace();


        }
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }


}

推荐答案

类Fragment中不存在getApplicationContext()方法.但是，它确实存在于类Activity中，因此您可以使用getActivity().getApplicationContext()从片段对象中获取上下文. (假设该片段已附加到活动中，因此getActivity()将返回一个非空对象，通常为true)

The method getApplicationContext() does not exist in the class Fragment. It does exist, however, in the class Activity, so you can use getActivity().getApplicationContext() to get the context from within a fragment object. (Assuming the fragment is attached to an activity so getActivity() will return a non-null object, which is usually true)

这篇关于Android的getApplicationContext()错误的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！