第二章:java I/O应用
效果：





main。xml

package i.o.test;import java.io.File;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.widget.Button;import android.widget.EditText;import android.widget.TextView;public class IOTest extends Activity {    /** Called when the activity is first created. */private Button bt;private EditText text;private TextView message;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        bt=(Button)findViewById(R.id.search);        text=(EditText)findViewById(R.id.text);        message=(TextView)findViewById(R.id.message);        bt.setOnClickListener(new Button.OnClickListener(){        public void onClick(View v){        String str=text.getText().toString();        if(str.equals("")){        message.setText("输入内容不能为空！");        }else{        message.setText(searchFile(str));        }        }        });    }        public String searchFile(String str){    String result="";    File[] fils=new File("/").listFiles();    for(File f:fils){    if(f.getName().indexOf(str)>=0){    result=result+f.getPath()+"\n";    }    }    if(result.equals("")){    result="没有该文件！";    }return result;    }}