setOnClickListener导致“ RuntimeException：无法启动”-NullPointerException

您必须先致电

setContentView(R.layout.rss_reader);

OnClickListeners

package com.cris96.rssreader;import android.os.Bundle;import android.app.Activity;import android.view.View;import android.widget.Button;public class RssReader extends Activity {    private Button button1;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.rss_reader);        button1 = (Button) findViewById(R.id.b1);        button1.setonClickListener(new View.onClickListener() { public void onClick(View v) {     System.out.println("test"); }        });    }}