JAVA-Android错误：应用程序意外停止，请重试

我制作了一个应用程序，它运行得很好。但是当我点击cancel或ok按钮时，模拟器没有将我链接到result.java，而是告诉我应用程序意外停止请再试一次下面是代码

import android.app.Activity;
import android.content.ComponentName; 
import android.content.Intent;
import android.database.CursorJoiner.Result;
import android.os.Bundle;
import android.view.View;
import android.widget.AutoCompleteTextView;

public class lib_main extends Activity {

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }

    public void onAddClick (View botton){

        AutoCompleteTextView title = (AutoCompleteTextView)findViewById(R.id.Title);
        AutoCompleteTextView author = (AutoCompleteTextView)findViewById(R.id.Author); 
        AutoCompleteTextView isbn = (AutoCompleteTextView)findViewById(R.id.ISBN);

        Intent intent = new Intent();
        intent.setClass(this,Result.class);

        intent.putExtra("Title", title.getText().toString());
        intent.putExtra("Author", author.getText().toString()); 
        intent.putExtra("ISBN", isbn.getText().toString());
        startActivity(intent);
    }

    public void onCancelClick(View botton){

        Intent intent = new Intent();
        intent.setComponent(new ComponentName(this,Result.class));

        intent.putExtra("Cancel","Cancel");
        startActivity(intent);
    }
}

这是result.java

import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;

public class Result extends Activity {

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.result);

        TextView resultText=(TextView)findViewById(R.id.resultText);

        Bundle bundle =getIntent().getExtras();
        if(bundle.getString("Cancel")!= null)
        {
           resultText.setText("operation cancel");
        }
        else
        {  
           String book =bundle.getString ("Title");
           String title =bundle.getString ("Author");
           String isbn =bundle.getString ("ISBN");
           resultText.setText(getString (R.string.resultOk)+""+book+""+ title+""+isbn);

        }
    }
}

---

错误日志运行时未写入命令输出：“am start-n com.Library.doc/com.Library.doc.lib_main-a android.intent.action.main-c android.intent.category.LAUNCHER”在device emulator-5554中，请尝试将代码格式化为可以正常读取的格式。您是否搜索了stackoverflow？：请尝试将代码格式化为可以正常阅读的格式。你搜索过stackoverflow吗