很久没有写东西了，鉴于某某同学文件管理器不会，这里简单介绍一下，同时写一个demon，参考了网上别人写的代码，自己也学习学习，研究研究。
首先所谓文件管理器，看起来就是一个列表，列表里面是文件夹或者文件，首先把布局写出来，我想在最上方的左边显示文件的路径，右边显示该路径下的文件个数，其实还是一个遍历文件，然后用列表显示出来的问题。下面是listview，用来显示文件列表。下面是运行的效果图：
主界面的布局文件如下:
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<?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方法里面调用一个方法去获取布局文件里面的id：
@override
protected void oncreate (bundle savedinstancestate) {
super.oncreate(savedinstancestate);
setcontentview(r.layout.file_manager);
initview();
}
initview之后添加apk的权限，777 表示可读可写可操作。
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权限的方法：
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;
}
完了之后我们要获取根目录下面的所有的数据，然后设置到我们的listview中让它显示出来。
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 + "项");
if (null != filterfiles && filterfiles.length > 0) {
for (file file : filterfiles) {
files.add(file);
}
}
mfileadpter = new filelistadapter(this, files, isroot);
mlistview.setadapter(mfileadpter);
}
首先是获取当前是否是根目录，然后把文件的路径设置给我们要显示的view。
然后用一个arraylist来装我们目录下的所有的文件或者文件夹。
首先要把这个文件夹的父类装到我们的列表中去，然后把这个文件夹下的子文件都拿到，也装在列表中，然后调用adapter显示出来。既然说到了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("返回上一级");
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("文件夹");
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项分2行显示，上面一行显示文件名
下面一行分别显示文件大小，文件类型，文件修改时间。
我们可以通过file file = (file) getitem(position);拿到item项的文件，如果是在第一个并且不再根目录我们就把第一个也就是parentfile显示为：“返回上一级”，下一行的都隐藏掉。
如果不是第一个位置，可以拿到这个文件的一系列信息。
先把string filename = file.getname();文件名拿到，显示出来。
如果这个文件是一个文件夹，就把文件的大小显示为“文件夹”，类型和修改时间隐藏掉。
如果不是一个文件夹， 可以拿到文件的长度long filesize = file.length();
根据特定的长度显示文件的大小，b， kb， mb， gb等。
然后拿到文件的类型，通过最后一个“.”之后的字符串就是该文件的类型。
通过viewholder.data.settext(new simpledateformat("yyyy/mm/dd hh:mm").format(file.lastmodified())); 设置文件的最近修改时间。
然后可以设置每个item项的点击事件，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("权限不足").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);
}
}
如果这个文件不能读，就弹出对话框显示“权限不足”。
如果是一个文件夹，就在调用一次显示所有文件的方法：initdata(file);把这个文件夹作为参数传递下去。
如果是一个文件，就可以调用打开文件的方法打开这个文件。
如何打开文件呢？
可以根据不同的文件的后缀名找到不同的文件类型：
可以用一个二维数组把一些常用的文件类型封装起来。如下：
private final string[][] mime_maptable = {
// {后缀名， mime类型}
{ ".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" },
{ "", "*/*" }
};
分别对应的是后缀名和对应的文件类型。
我们可以根据文件的后缀名拿到文件的mimetype类型：
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;
}
先遍历后缀名，如果找到，就把对应的类型找到并返回。
拿到了类型，就可以打开这个文件。
用这个intent.setdataandtype(uri.fromfile(file), type); 打开设置打开文件的类型。
如果type是*/*会弹出所有的可供选择的应用程序。
到这里一个简易的文件管理器就成型了。
源代码：
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 + "项");
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("返回上一级");
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("文件夹");
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("权限不足").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, "未知类型，不能打开", 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 = {
// {后缀名， mime类型}
{ ".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" },
{ "", "*/*" }
};
}
最后补充一下，布局文件中的dimension是编译到jar包里面去了的，没有jar包的童鞋可以改成自己定义大小。
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