很久沒有寫東西了，鑒于某某同學文件管理器不會，這里簡單介紹一下，同時寫一個demon，參考了網上別人寫的代碼，自己也學習學習，研究研究。
首先所謂文件管理器，看起來就是一個列表，列表里面是文件夾或者文件，首先把布局寫出來，我想在最上方的左邊顯示文件的路徑，右邊顯示該路徑下的文件個數，其實還是一個遍歷文件，然后用列表顯示出來的問題。下面是ListView，用來顯示文件列表。下面是運行的效果圖：
主界面的布局文件如下:
<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <RelativeLayout android:id="@+id/top" android:layout_width="match_parent" android:layout_height="wrap_content"> <TextView android:id="@+id/path" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_centerVertical="true" android:textSize="@*android:dimen/list_item_size" android:textColor="@android:color/white"/> <TextView android:id="@+id/item_count" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textSize="@*android:dimen/list_item_size" android:textColor="@android:color/white" android:layout_alignParentRight="true" android:layout_centerVertical="true"/> </RelativeLayout> <View android:layout_width="match_parent" android:layout_height="2dip" android:background="#09c"/> <LinearLayout android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> <ListView android:id="@+id/file_list" android:layout_height="match_parent" android:layout_width="match_parent" android:fadingEdge="none" android:cacheColorHint="@android:color/transparent"/> </LinearLayout></LinearLayout>
首先在oncreate方法里面調用一個方法去獲取布局文件里面的id：
@Override protected void onCreate (Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.file_manager); initView(); }initView之后添加apk的權限，777 表示可讀可寫可操作。
private void initView() { mListView = (ListView) findViewById(R.id.file_list); mPathView = (TextView) findViewById(R.id.path); mItemCount = (TextView) findViewById(R.id.item_count); mListView.setOnItemClickListener(this); String apkRoot = "chmod 777 " + getPackageCodePath(); RootCommand(apkRoot); File folder = new File("/"); initData(folder); } 修改Root權限的方法：
public static boolean RootCommand (String command) { Process process = null; DataOutputStream os = null; try { process = Runtime.getRuntime().exec("su"); os = new DataOutputStream(process.getOutputStream()); os.writeBytes(command + "/n"); os.writeBytes("exit/n"); os.flush(); process.waitFor(); } catch (Exception e) { return false; } finally { try { if (os != null) { os.close(); } process.destroy(); } catch (Exception e) { e.printStackTrace(); } } return true; }完了之后我們要獲取根目錄下面的所有的數據，然后設置到我們的ListView中讓它顯示出來。
private void initData(File folder) { boolean isRoot = folder.getParent() == null; mPathView.setText(folder.getAbsolutePath()); ArrayList<File> files = new ArrayList<File>(); if (!isRoot) { files.add(folder.getParentFile()); } File[] filterFiles = folder.listFiles(); mItemCount.setText(filterFiles.length + "項"); if (null != filterFiles && filterFiles.length > 0) { for (File file : filterFiles) { files.add(file); } } mFileAdpter = new FileListAdapter(this, files, isRoot); mListView.setAdapter(mFileAdpter); }首先是獲取當前是否是根目錄，然后把文件的路徑設置給我們要顯示的View。
然后用一個ArrayList來裝我們目錄下的所有的文件或者文件夾。
首先要把這個文件夾的父類裝到我們的列表中去，然后把這個文件夾下的子文件都拿到，也裝在列表中，然后調用Adapter顯示出來。既然說到了Adapter, 那就看下Adapter吧。
private class FileListAdapter extends BaseAdapter { private Context context; private ArrayList<File> files; private boolean isRoot; private LayoutInflater mInflater; public FileListAdapter (Context context, ArrayList<File> files, boolean isRoot) { this.context = context; this.files = files; this.isRoot = isRoot; mInflater = LayoutInflater.from(context); } @Override public int getCount () { return files.size(); } @Override public Object getItem (int position) { return files.get(position); } @Override public long getItemId (int position) { return position; } @Override public View getView (int position, View convertView, ViewGroup parent) { ViewHolder viewHolder; if(convertView == null) { viewHolder = new ViewHolder(); convertView = mInflater.inflate(R.layout.file_list_item, null); convertView.setTag(viewHolder); viewHolder.title = (TextView) convertView.findViewById(R.id.file_title); viewHolder.type = (TextView) convertView.findViewById(R.id.file_type); viewHolder.data = (TextView) convertView.findViewById(R.id.file_date); viewHolder.size = (TextView) convertView.findViewById(R.id.file_size); } else { viewHolder = (ViewHolder) convertView.getTag(); } File file = (File) getItem(position); if(position == 0 && !isRoot) { viewHolder.title.setText("返回上一級"); viewHolder.data.setVisibility(View.GONE); viewHolder.size.setVisibility(View.GONE); viewHolder.type.setVisibility(View.GONE); } else { String fileName = file.getName(); viewHolder.title.setText(fileName); if(file.isDirectory()) { viewHolder.size.setText("文件夾"); viewHolder.size.setTextColor(Color.RED); viewHolder.type.setVisibility(View.GONE); viewHolder.data.setVisibility(View.GONE); } else { long fileSize = file.length(); if(fileSize > 1024*1024) { float size = fileSize /(1024f*1024f); viewHolder.size.setText(new DecimalFormat("#.00").format(size) + "MB"); } else if(fileSize >= 1024) { float size = fileSize/1024; viewHolder.size.setText(new DecimalFormat("#.00").format(size) + "KB"); } else { viewHolder.size.setText(fileSize + "B"); } int dot = fileName.indexOf('.'); if(dot > -1 && dot < (fileName.length() -1)) { viewHolder.type.setText(fileName.substring(dot + 1) + "文件"); } viewHolder.data.setText(new SimpleDateFormat("yyyy/MM/dd HH:mm").format(file.lastModified())); } } return convertView; } class ViewHolder { private TextView title; private TextView type; private TextView data; private TextView size; } }看下adapter的布局文件：
<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <TextView android:id="@+id/file_title" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textSize="25sp" android:textColor="#fff000"/> <LinearLayout android:id="@+id/file_info" android:layout_width="match_parent" android:layout_height="wrap_content"> <TextView android:id="@+id/file_size" android:layout_width="0dip" android:layout_height="wrap_content" android:textColor="#ffffcc" android:layout_weight="1" android:textSize="18sp"/> <TextView android:id="@+id/file_type" android:layout_width="0dip" android:layout_height="wrap_content" android:textColor="#ffffcc" android:layout_weight="1" android:gravity="right" android:textSize="18sp"/> <TextView android:id="@+id/file_date" android:layout_width="0dip" android:layout_height="wrap_content" android:textColor="#ffffff" android:layout_weight="1" android:gravity="right" android:textSize="18sp"/> </LinearLayout></LinearLayout>
列表的Item項分2行顯示，上面一行顯示文件名
下面一行分別顯示文件大小，文件類型，文件修改時間。
我們可以通過File file = (File) getItem(position);拿到Item項的文件，如果是在第一個并且不再根目錄我們就把第一個也就是parentFile顯示為：“返回上一級”，下一行的都隱藏掉。
如果不是第一個位置，可以拿到這個文件的一系列信息。
先把String fileName = file.getName();文件名拿到，顯示出來。
如果這個文件是一個文件夾，就把文件的大小顯示為“文件夾”，類型和修改時間隱藏掉。
如果不是一個文件夾， 可以拿到文件的長度long fileSize = file.length();
根據特定的長度顯示文件的大小，B， KB， MB， GB等。
然后拿到文件的類型，通過最后一個“.”之后的字符串就是該文件的類型。
通過viewHolder.data.setText(new SimpleDateFormat("yyyy/MM/dd HH:mm").format(file.lastModified())); 設置文件的最近修改時間。
然后可以設置每個Item項的點擊事件，如下所示：
@Override public void onItemClick (AdapterView<?> parent, View view, int position, long id) { File file = (File) mFileAdpter.getItem(position); if(!file.canRead()) { new AlertDialog.Builder(this).setTitle("提示").setMessage("權限不足").setPositiveButton(android.R.string.ok, new OnClickListener() { @Override public void onClick (DialogInterface dialog, int which) { } }).show(); } else if(file.isDirectory()) { initData(file); } else { openFile(file); } }如果這個文件不能讀，就彈出對話框顯示“權限不足”。
如果是一個文件夾，就在調用一次顯示所有文件的方法：initData(file);把這個文件夾作為參數傳遞下去。
如果是一個文件，就可以調用打開文件的方法打開這個文件。
如何打開文件呢？
可以根據不同的文件的后綴名找到不同的文件類型：
可以用一個二維數組把一些常用的文件類型封裝起來。如下：
private final String[][] MIME_MapTable = { // {后綴名， MIME類型} { ".3gp", "video/3gpp" }, { ".apk", "application/vnd.android.package-archive" }, { ".asf", "video/x-ms-asf" }, { ".avi", "video/x-msvideo" }, { ".bin", "application/octet-stream" }, { ".bmp", "image/bmp" }, { ".c", "text/plain" }, { ".class", "application/octet-stream" }, { ".conf", "text/plain" }, { ".cpp", "text/plain" }, { ".doc", "application/msword" }, { ".docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document" }, { ".xls", "application/vnd.ms-excel" }, { ".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" }, { ".exe", "application/octet-stream" }, { ".gif", "image/gif" }, { ".gtar", "application/x-gtar" }, { ".gz", "application/x-gzip" }, { ".h", "text/plain" }, { ".htm", "text/html" }, { ".html", "text/html" }, { ".jar", "application/java-archive" }, { ".java", "text/plain" }, { ".jpeg", "image/jpeg" }, { ".jpg", "image/jpeg" }, { ".js", "application/x-javascript" }, { ".log", "text/plain" }, { ".m3u", "audio/x-mpegurl" }, { ".m4a", "audio/mp4a-latm" }, { ".m4b", "audio/mp4a-latm" }, { ".m4p", "audio/mp4a-latm" }, { ".m4u", "video/vnd.mpegurl" }, { ".m4v", "video/x-m4v" }, { ".mov", "video/quicktime" }, { ".mp2", "audio/x-mpeg" }, { ".mp3", "audio/x-mpeg" }, { ".mp4", "video/mp4" }, { ".mpc", "application/vnd.mpohun.certificate" }, { ".mpe", "video/mpeg" }, { ".mpeg", "video/mpeg" }, { ".mpg", "video/mpeg" }, { ".mpg4", "video/mp4" }, { ".mpga", "audio/mpeg" }, { ".msg", "application/vnd.ms-outlook" }, { ".ogg", "audio/ogg" }, { ".pdf", "application/pdf" }, { ".png", "image/png" }, { ".pps", "application/vnd.ms-powerpoint" }, { ".ppt", "application/vnd.ms-powerpoint" }, { ".pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation" }, { ".prop", "text/plain" }, { ".rc", "text/plain" }, { ".rmvb", "audio/x-pn-realaudio" }, { ".rtf", "application/rtf" }, { ".sh", "text/plain" }, { ".tar", "application/x-tar" }, { ".tgz", "application/x-compressed" }, { ".txt", "text/plain" }, { ".wav", "audio/x-wav" }, { ".wma", "audio/x-ms-wma" }, { ".wmv", "audio/x-ms-wmv" }, { ".wps", "application/vnd.ms-works" }, { ".xml", "text/plain" }, { ".z", "application/x-compress" }, { ".zip", "application/x-zip-compressed" }, { "", "*/*" } };分別對應的是后綴名和對應的文件類型。
我們可以根據文件的后綴名拿到文件的MIMEType類型：
private String getMIMEType(File file) { String type = "*/*"; String fileName = file.getName(); int dotIndex = fileName.indexOf('.'); if(dotIndex < 0) { return type; } String end = fileName.substring(dotIndex, fileName.length()).toLowerCase(); if(end == "") { return type; } for(int i=0; i<MIME_MapTable.length; i++) { if(end == MIME_MapTable[i][0]) { type = MIME_MapTable[i][1] ; } } return type; }先遍歷后綴名，如果找到，就把對應的類型找到并返回。
拿到了類型，就可以打開這個文件。
用這個intent.setDataAndType(Uri.fromFile(file), type); 打開設置打開文件的類型。
如果type是*/*會彈出所有的可供選擇的應用程序。
到這里一個簡易的文件管理器就成型了。
源代碼：
package com.android.test;import java.io.DataOutputStream;import java.io.File;import java.text.DecimalFormat;import java.text.SimpleDateFormat;import java.util.ArrayList;import android.app.Activity;import android.app.AlertDialog;import android.content.Context;import android.content.DialogInterface;import android.content.Intent;import android.content.DialogInterface.OnClickListener;import android.graphics.Color;import android.net.Uri;import android.os.Bundle;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.AdapterView;import android.widget.AdapterView.OnItemClickListener;import android.widget.BaseAdapter;import android.widget.ListView;import android.widget.TextView;import android.widget.Toast;public class FileManager extends Activity implements OnItemClickListener { private ListView mListView; private TextView mPathView; private FileListAdapter mFileAdpter; private TextView mItemCount; @Override protected void onCreate (Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.file_manager); initView(); } private void initView() { mListView = (ListView) findViewById(R.id.file_list); mPathView = (TextView) findViewById(R.id.path); mItemCount = (TextView) findViewById(R.id.item_count); mListView.setOnItemClickListener(this); String apkRoot = "chmod 777 " + getPackageCodePath(); RootCommand(apkRoot); File folder = new File("/"); initData(folder); } public static boolean RootCommand (String command) { Process process = null; DataOutputStream os = null; try { process = Runtime.getRuntime().exec("su"); os = new DataOutputStream(process.getOutputStream()); os.writeBytes(command + "/n"); os.writeBytes("exit/n"); os.flush(); process.waitFor(); } catch (Exception e) { return false; } finally { try { if (os != null) { os.close(); } process.destroy(); } catch (Exception e) { e.printStackTrace(); } } return true; } private void initData(File folder) { boolean isRoot = folder.getParent() == null; mPathView.setText(folder.getAbsolutePath()); ArrayList<File> files = new ArrayList<File>(); if (!isRoot) { files.add(folder.getParentFile()); } File[] filterFiles = folder.listFiles(); mItemCount.setText(filterFiles.length + "項"); if (null != filterFiles && filterFiles.length > 0) { for (File file : filterFiles) { files.add(file); } } mFileAdpter = new FileListAdapter(this, files, isRoot); mListView.setAdapter(mFileAdpter); } private class FileListAdapter extends BaseAdapter { private Context context; private ArrayList<File> files; private boolean isRoot; private LayoutInflater mInflater; public FileListAdapter (Context context, ArrayList<File> files, boolean isRoot) { this.context = context; this.files = files; this.isRoot = isRoot; mInflater = LayoutInflater.from(context); } @Override public int getCount () { return files.size(); } @Override public Object getItem (int position) { return files.get(position); } @Override public long getItemId (int position) { return position; } @Override public View getView (int position, View convertView, ViewGroup parent) { ViewHolder viewHolder; if(convertView == null) { viewHolder = new ViewHolder(); convertView = mInflater.inflate(R.layout.file_list_item, null); convertView.setTag(viewHolder); viewHolder.title = (TextView) convertView.findViewById(R.id.file_title); viewHolder.type = (TextView) convertView.findViewById(R.id.file_type); viewHolder.data = (TextView) convertView.findViewById(R.id.file_date); viewHolder.size = (TextView) convertView.findViewById(R.id.file_size); } else { viewHolder = (ViewHolder) convertView.getTag(); } File file = (File) getItem(position); if(position == 0 && !isRoot) { viewHolder.title.setText("返回上一級"); viewHolder.data.setVisibility(View.GONE); viewHolder.size.setVisibility(View.GONE); viewHolder.type.setVisibility(View.GONE); } else { String fileName = file.getName(); viewHolder.title.setText(fileName); if(file.isDirectory()) { viewHolder.size.setText("文件夾"); viewHolder.size.setTextColor(Color.RED); viewHolder.type.setVisibility(View.GONE); viewHolder.data.setVisibility(View.GONE); } else { long fileSize = file.length(); if(fileSize > 1024*1024) { float size = fileSize /(1024f*1024f); viewHolder.size.setText(new DecimalFormat("#.00").format(size) + "MB"); } else if(fileSize >= 1024) { float size = fileSize/1024; viewHolder.size.setText(new DecimalFormat("#.00").format(size) + "KB"); } else { viewHolder.size.setText(fileSize + "B"); } int dot = fileName.indexOf('.'); if(dot > -1 && dot < (fileName.length() -1)) { viewHolder.type.setText(fileName.substring(dot + 1) + "文件"); } viewHolder.data.setText(new SimpleDateFormat("yyyy/MM/dd HH:mm").format(file.lastModified())); } } return convertView; } class ViewHolder { private TextView title; private TextView type; private TextView data; private TextView size; } } @Override public void onItemClick (AdapterView<?> parent, View view, int position, long id) { File file = (File) mFileAdpter.getItem(position); if(!file.canRead()) { new AlertDialog.Builder(this).setTitle("提示").setMessage("權限不足").setPositiveButton(android.R.string.ok, new OnClickListener() { @Override public void onClick (DialogInterface dialog, int which) { } }).show(); } else if(file.isDirectory()) { initData(file); } else { openFile(file); } } private void openFile(File file) { Intent intent = new Intent(); intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); intent.setAction(Intent.ACTION_VIEW); String type = getMIMEType(file); intent.setDataAndType(Uri.fromFile(file), type); try { startActivity(intent); } catch (Exception e) { Toast.makeText(this, "未知類型，不能打開", Toast.LENGTH_SHORT).show(); } } private String getMIMEType(File file) { String type = "*/*"; String fileName = file.getName(); int dotIndex = fileName.indexOf('.'); if(dotIndex < 0) { return type; } String end = fileName.substring(dotIndex, fileName.length()).toLowerCase(); if(end == "") { return type; } for(int i=0; i<MIME_MapTable.length; i++) { if(end == MIME_MapTable[i][0]) { type = MIME_MapTable[i][1] ; } } return type; } private final String[][] MIME_MapTable = { // {后綴名， MIME類型} { ".3gp", "video/3gpp" }, { ".apk", "application/vnd.android.package-archive" }, { ".asf", "video/x-ms-asf" }, { ".avi", "video/x-msvideo" }, { ".bin", "application/octet-stream" }, { ".bmp", "image/bmp" }, { ".c", "text/plain" }, { ".class", "application/octet-stream" }, { ".conf", "text/plain" }, { ".cpp", "text/plain" }, { ".doc", "application/msword" }, { ".docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document" }, { ".xls", "application/vnd.ms-excel" }, { ".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" }, { ".exe", "application/octet-stream" }, { ".gif", "image/gif" }, { ".gtar", "application/x-gtar" }, { ".gz", "application/x-gzip" }, { ".h", "text/plain" }, { ".htm", "text/html" }, { ".html", "text/html" }, { ".jar", "application/java-archive" }, { ".java", "text/plain" }, { ".jpeg", "image/jpeg" }, { ".jpg", "image/jpeg" }, { ".js", "application/x-javascript" }, { ".log", "text/plain" }, { ".m3u", "audio/x-mpegurl" }, { ".m4a", "audio/mp4a-latm" }, { ".m4b", "audio/mp4a-latm" }, { ".m4p", "audio/mp4a-latm" }, { ".m4u", "video/vnd.mpegurl" }, { ".m4v", "video/x-m4v" }, { ".mov", "video/quicktime" }, { ".mp2", "audio/x-mpeg" }, { ".mp3", "audio/x-mpeg" }, { ".mp4", "video/mp4" }, { ".mpc", "application/vnd.mpohun.certificate" }, { ".mpe", "video/mpeg" }, { ".mpeg", "video/mpeg" }, { ".mpg", "video/mpeg" }, { ".mpg4", "video/mp4" }, { ".mpga", "audio/mpeg" }, { ".msg", "application/vnd.ms-outlook" }, { ".ogg", "audio/ogg" }, { ".pdf", "application/pdf" }, { ".png", "image/png" }, { ".pps", "application/vnd.ms-powerpoint" }, { ".ppt", "application/vnd.ms-powerpoint" }, { ".pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation" }, { ".prop", "text/plain" }, { ".rc", "text/plain" }, { ".rmvb", "audio/x-pn-realaudio" }, { ".rtf", "application/rtf" }, { ".sh", "text/plain" }, { ".tar", "application/x-tar" }, { ".tgz", "application/x-compressed" }, { ".txt", "text/plain" }, { ".wav", "audio/x-wav" }, { ".wma", "audio/x-ms-wma" }, { ".wmv", "audio/x-ms-wmv" }, { ".wps", "application/vnd.ms-works" }, { ".xml", "text/plain" }, { ".z", "application/x-compress" }, { ".zip", "application/x-zip-compressed" }, { "", "*/*" } };}最后補充一下，布局文件中的dimension是編譯到jar包里面去了的，沒有jar包的童鞋可以改成自己定義大小。
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持武林網。
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