Android-容易的sdcard文件浏览

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    tools:context="com.example.fanlei.myservicedemo.FilePathActivity">    <android.support.v7.widget.Toolbar        android:layout_width="match_parent"        android:layout_height="?attr/actionBarSize"        android:background="#000">        <Button            android:id="@+id/button"            android:layout_width="wrap_content"            android:layout_height="match_parent"            android:text="返回上一级"/>    </android.support.v7.widget.Toolbar>    <ListView        android:id="@+id/listView"        android:layout_width="match_parent"        android:layout_height="match_parent">    </ListView></LinearLayout>

  1 package com.example.fanlei.myservicedemo;  2   3 import android.annotation.TargetApi;  4 import android.os.Build;  5 import android.os.Bundle;  6 import android.os.Environment;  7 import android.support.v7.app.ActionBarActivity;  8 import android.view.View;  9 import android.widget.AdapterView; 10 import android.widget.ArrayAdapter; 11 import android.widget.Button; 12 import android.widget.ListView; 13 import android.widget.Toast; 14 import java.io.File; 15 import java.util.ArrayList; 16 import java.util.List; 17  18 public class FilePathActivity extends ActionBarActivity { 19  20  21     private ListView listView; 22     private File currentParent;   //记录父文件夹 23     private File[] currentFiles;  //记录当前路径下的所有文件的文件数组 24     private List<String> fileName;//文件或文件夹名字 25  26     private ArrayAdapter arrayAdapter; 27     private Button button; 28  29     @TargetApi(Build.VERSION_CODES.KITKAT) 30     @Override 31     protected void onCreate(Bundle savedInstanceState) { 32         super.onCreate(savedInstanceState); 33         setContentView(R.layout.activity_file_path); 34  35         //判断一下有木有sdcard卡 36         if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){ 37             initView(); 38             initData(); 39             initEvent(); 40         }else { 41             Toast.makeText(this,"无sdcard卡",Toast.LENGTH_LONG).show(); 42         } 43  44     } 45  46     private void initView(){ 47         listView = (ListView) findViewById(R.id.listView); 48         button = (Button) findViewById(R.id.button); 49     } 50  51     private void initData(){ 52         currentParent = Environment.getExternalStorageDirectory(); 53         currentFiles = currentParent.listFiles(); 54         fileName = new ArrayList<>(); 55         List<String> temp = filesToFileName(currentFiles); 56         fileName.addAll(temp); 57         arrayAdapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1,fileName); 58         listView.setAdapter(arrayAdapter); 59     } 60  61     private void initEvent(){ 62         listView.setOnItemClickListener(new AdapterView.OnItemClickListener() { 63             @Override 64             public void onItemClick(AdapterView<?> parent, View view, int position, long id) { 65                 if (!currentFiles[position].isFile()){ 66                     File[] temp = currentFiles[position].listFiles(); 67                     if (temp == null || temp.length == 0){ 68                         Toast.makeText(FilePathActivity.this,"该文件下已无文件",Toast.LENGTH_LONG).show(); 69                     }else { 70                         currentParent = currentFiles[position]; 71                         currentFiles = temp; 72                         fileName.clear(); 73                         fileName.addAll(filesToFileName(currentFiles)); 74                         arrayAdapter.notifyDataSetChanged(); 75                     } 76                 } 77             } 78         }); 79         //返回键 80         button.setOnClickListener(new View.OnClickListener() { 81             @Override 82             public void onClick(View v) { 83                 if (!currentParent.getPath().equals(Environment.getExternalStorageDirectory().getPath())){ 84                     currentParent = currentParent.getParentFile(); 85                     currentFiles = currentParent.listFiles(); 86                     fileName.clear(); 87                     fileName.addAll(filesToFileName(currentFiles)); 88                     arrayAdapter.notifyDataSetChanged(); 89                 } 90             } 91         }); 92     } 93     //返回一个File的文件名的数组 94     private List<String> filesToFileName(File[] files){ 95         List<String> fileName = new ArrayList<>(); 96         for (int i = 0;i < files.length;i++){ 97             if (!files[i].getName().substring(0,1).equals(".")){  //这个地方我把“.”开头的文件夹不让其显示 98                 fileName.add(files[i].getName()); 99             }100         }101         return fileName;102     }103 }