Question

按照制作应用程序的教程我遇到了问题。但现在我通过添加回复得到错误一个按钮。它在public void sendMessage中给出了一个错误，但我看不出有什么问题。

 package com.example.myfirstapp;

import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.content.Intent;




/** Called when the user clicks the Send button */

public void sendMessage(View view){

Intent intent = new Intent(this, DisplayMessageActivity.class);
}


public class MainActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }


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

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}

Answer 1

那些行

/** Called when the user clicks the Send button */

public void sendMessage(View view){ 
  Intent intent = new Intent(this, DisplayMessageActivity.class);
}

在

之后进入你的班级

public class MainActivity extends ActionBarActivity {

Answer 2

您的功能不在活动范围内。

移动

public void sendMessage(View view){

    Intent intent = new Intent(this, DisplayMessageActivity.class);
}

内部活动如下：

public class MainActivity extends ActionBarActivity {

    //other code i.e. onCreate etc

    public void sendMessage(View view){
        Intent intent = new Intent(this, DisplayMessageActivity.class);
    }

}

Android SDK public void出错

2 个答案: