Android Studio中的OnClickListener

Question

我正在尝试使用新的Android Studio开发和应用，但是我的OnClickListener始终收到重大错误。主要是告诉我它无法解析符号“
setOnClickListener”，也无法解析“ View v”

package com.sigmachi.derbydays;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity {

    @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;
    }

    Button button= (Button) findViewById(R.id.standingsButton);
    button.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            startActivity(new Intent(MainActivity.this,StandingsActivity.class));
        }
    });

那是班上的代码

Information:Compilation completed with 11 errors and 0 warnings in 4 sec
Information:11 errors
Information:0 warnings
/Users/angelo/AndroidStudioProjects/SigmaChiDerbyDaysProject/SigmaChiDerbyDays/src/main/java/com/sigmachi/derbydays/MainActivity.java
    Error:Error:line (28)Gradle: <identifier> expected
    Error:Error:line (28)Gradle: illegal start of type
    Error:Error:line (28)Gradle: ')' expected
    Error:Error:line (28)Gradle: ';' expected
    Error:Error:line (28)Gradle: invalid method declaration; return type required
    Error:Error:line (30)Gradle: illegal start of type
    Error:Error:line (30)Gradle: ';' expected
    Error:Error:line (30)Gradle: ')' expected
    Error:Error:line (30)Gradle: not a statement
    Error:Error:line (30)Gradle: ';' expected
    Error:Error:line (33)Gradle: illegal start of type

这些是我收到的错误，绝对没有道理。28行开始于button.setOnClickListener

编辑：现在当我按下按钮时，我收到一个强制关闭

这是应该打开的类，仅有的类是唯一的变化是要打开的布局

package com.sigmachi.derbydays;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;

public class StandingsActivity extends Activity {

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


    @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;
    }

}

Answer 1

Button button= (Button) findViewById(R.id.standingsButton);
button.setOnClickListener(new View.OnClickListener() {
    public void onClick(View v) {
        startActivity(new Intent(MainActivity.this,StandingsActivity.class));
    }
});

此代码不是任何方法。如果要使用它，它必须位于类似OnCreate()

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

    Button button= (Button) findViewById(R.id.standingsButton);
    button.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            startActivity(new Intent(MainActivity.this,StandingsActivity.class));
        }
    });
}