按照字母查找手机文件

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="请输入查找的内容" />

<EditText
android:id="@+id/edt"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />

<Button
android:id="@+id/btn"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

<TextView
android:id="@+id/tv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:isScrollContainer="true" />

</LinearLayout>

package com.example.searchfile;

import java.io.File;

import android.os.Bundle;
import android.app.Activity;
import android.text.TextUtils;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends Activity {
private EditText edt ;
private TextView tv;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
edt = (EditText) findViewById(R.id.edt);
tv = (TextView) findViewById(R.id.tv);
findViewById(R.id.btn).setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
String key = edt.getText().toString().trim();
if(TextUtils.isEmpty(key)){
tv.setText("输入的不能为空");
}else{
tv.setText(searchFile(key));
}

}
});
}
private String searchFile(String keyword){
String msg = "";
//获得根目录下的所有文件
File[] file = new File("/").listFiles();
//遍历此数组
for (int i = 0; i < file.length; i++) {
if(file[i].getName().indexOf(keyword)>=0){
msg += file[i].getPath()+"\n";
}
}
if(msg.equals("")){
msg = "找不到此文件";
}
return msg;
}

}