介绍
本篇介绍Android获取本机各种类型文件的方法，已经封装成工具类，末尾有源码下载地址。
提示
获取音乐、视频、图片、文档等文件是需要有读取SD卡的权限的，如果是6.0以下的系统，则直接在清单文件中声明SD卡读取权限即可；如果是6.0或以上，则需要动态申请权限。
FileManager的使用
FileManager是封装好的用于获取本机各类文件的工具类，使用方式如：FileManager.getInstance(Context context).getMusics()，使用的是单例模式创建：
private static FileManager mInstance;
private static Context mContext;
public static ContentResolver mContentResolver;
private static Object mLock = new Object();
public static FileManager getInstance(Context context){
if (mInstance == null){
synchronized (mLock){
if (mInstance == null){
mInstance = new FileManager();
mContext = context;
mContentResolver = context.getContentResolver();
}
}
}
return mInstance;
}
获取音乐列表
private static ListgetMusics() { ArrayList musics = new ArrayList<>(); Cursor c = null; try { c = mContentResolver.query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, null, null, null, MediaStore.Audio.Media.DEFAULT_SORT_ORDER); while (c.moveTonext()) { String path = c.getString(c.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));// 路径 if (FileUtils.isExists(path)) { continue; } String name = c.getString(c.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME)); // 歌曲名 String album = c.getString(c.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM)); // 专辑 String artist = c.getString(c.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST)); // 作者 long size = c.getLong(c.getColumnIndexOrThrow(MediaStore.Audio.Media.SIZE));// 大小 int duration = c.getInt(c.getColumnIndexOrThrow(MediaStore.Audio.Media.DURATION));// 时长 int time = c.getInt(c.getColumnIndexOrThrow(MediaStore.Audio.Media._ID));// 歌曲的id // int albumId = c.getInt(c.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM_ID)); Music music = new Music(name, path, album, artist, size, duration); musics.add(music); } } catch (Exception e) { e.printStackTrace(); } finally { if (c != null) { c.close(); } } return musics; }
FileUtils中判断文件是否存在的方法isExists(String path)，代码为:
public static boolean isExists(String path) {
File file = new File(path);
return file.exists();
}
音乐的bean类Music代码为:
public class Music implements Comparable{ private String name; private String path; private String album; private String artist; private long size; private int duration; private String pinyin; public Music(String name, String path, String album, String artist, long size, int duration) { this.name = name; this.path = path; this.album = album; this.artist = artist; this.size = size; this.duration = duration; pinyin = PinyinUtils.getPinyin(name); } ... //此处省略setter和getter方法 }
PinyinUtils根据名字获取拼音，主要是用于音乐列表A-Z的排序，需要依赖pinyin4j.jar，获取拼音的方法getPinyin(String name)代码为：
public static String getPinyin(String str) {
// 设置拼音结果的格式
HanyuPinyinOutputFormat format = new HanyuPinyinOutputFormat();
format.setCaseType(HanyuPinyinCaseType.UPPERCASE);// 设置为大写形式
format.setToneType(HanyuPinyinToneType.WITHOUT_TONE);// 不用加入声调
StringBuilder sb = new StringBuilder();
char[] charArray = str.toCharArray();
for (int i = 0; i < charArray.length; i++) {
char c = charArray[i];
if (Character.isWhitespace(c)) {// 如果是空格则跳过
continue;
}
if (isHanZi(c)) {// 如果是汉字
String s = "";
try {
// toHanyuPinyinStringArray 返回一个字符串数组是因为该汉字可能是多音字，此处只取第一个结果
s = PinyinHelper.toHanyuPinyinStringArray(c, format)[0];
sb.append(s);
} catch (BadHanyuPinyinOutputFormatCombination e) {
e.printStackTrace();
sb.append(s);
}
} else {
// 不是汉字
if (i == 0) {
if (isEnglish(c)) {// 第一个属于字母，则返回该字母
return String.valueOf(c).toUpperCase(Locale.ENGLISH);
}
return "#"; // 不是的话返回#号
}
}
}
return sb.toString();
}
获取视频列表
private static List
其中，视频的bean类Video代码为：
public class Video {
private int id = 0;
private String path = null;
private String name = null;
private String resolution = null;// 分辨率
private long size = 0;
private long date = 0;
private long duration = 0;
public Video(int id, String path, String name, String resolution, long size, long date, long duration) {
this.id = id;
this.path = path;
this.name = name;
this.resolution = resolution;
this.size = size;
this.date = date;
this.duration = duration;
}
... //此处省略setter和getter方法
｝
通过本地视频id获取视频缩略图
// 获取视频缩略图
private static Bitmap getVideoThumbnail(int id) {
Bitmap bitmap = null;
BitmapFactory.Options options = new BitmapFactory.Options();
options.inDither = false;
options.inPreferredConfig = Bitmap.Config.ARGB_8888;
bitmap = MediaStore.Video.Thumbnails.getThumbnail(mContentResolver, id, MediaStore.Images.Thumbnails.MICRO_KIND, options);
return bitmap;
}
上面获取视频列表的方法中，Video对象中有一个属性是id，通过传入这个id可以获取到视频缩略图的Bitmap对象。
获取本机所有图片文件夹
private static List getImageFolders() {
List folders = new ArrayList();
// 扫描图片
Cursor c = null;
try {
c = mContentResolver.query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, null,
MediaStore.Images.Media.MIME_TYPE + "= ? or " + MediaStore.Images.Media.MIME_TYPE + "= ?",
new String[]{"image/jpeg", "image/png"}, MediaStore.Images.Media.DATE_MODIFIED);
List mDirs = new ArrayList();//用于保存已经添加过的文件夹目录
while (c.moveTonext()) {
String path = c.getString(c.getColumnIndex(MediaStore.Images.Media.DATA));// 路径
File parentFile = new File(path).getParentFile();
if (parentFile == null)
continue;
String dir = parentFile.getAbsolutePath();
if (mDirs.contains(dir))//如果已经添加过
continue;
mDirs.add(dir);//添加到保存目录的集合中
ImgFolderBean folderBean = new ImgFolderBean();
folderBean.setDir(dir);
folderBean.setFistImgPath(path);
if (parentFile.list() == null)
continue;
int count = parentFile.list(new FilenameFilter() {
@Override
public boolean accept(File dir, String filename) {
if (filename.endsWith(".jpeg") || filename.endsWith(".jpg") || filename.endsWith(".png")) {
return true;
}
return false;
}
}).length;
folderBean.setCount(count);
folders.add(folderBean);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (c != null) {
c.close();
}
}
return folders;
}
其中，图片文件夹的bean类ImgFolderBean代码为:
public class ImgFolderBean {
private String dir;
private String fistImgPath;
private String name;
private int count;
public ImgFolderBean(String dir, String fistImgPath, String name, int count) {
this.dir = dir;
this.fistImgPath = fistImgPath;
this.name = name;
this.count = count;
}
... //此处省略setter和getter方法
}
获取图片文件夹下的图片路径的集合
private static ListgetImgListByDir(String dir) { ArrayList imgPaths = new ArrayList<>(); File directory = new File(dir); if (directory == null || !directory.exists()) { return imgPaths; } File[] files = directory.listFiles(); for (File file : files) { String path = file.getAbsolutePath(); if (FileUtils.isPicFile(path)) { imgPaths.add(path); } } return imgPaths; }
获取本机已安装应用列表
private static List getAppInfos() {
ArrayList appInfos = new ArrayList();
//获取到包的管理者
PackageManager packageManager = mContext.getPackageManager();
//获得所有的安装包
List installedPackages = packageManager.getInstalledPackages(0);
//遍历每个安装包，获取对应的信息
for (PackageInfo packageInfo : installedPackages) {
AppInfo appInfo = new AppInfo();
appInfo.setApplicationInfo(packageInfo.applicationInfo);
appInfo.setVersionCode(packageInfo.versionCode);
//得到icon
Drawable drawable = packageInfo.applicationInfo.loadIcon(packageManager);
appInfo.setIcon(drawable);
//得到程序的名字
String apkName = packageInfo.applicationInfo.loadLabel(packageManager).toString();
appInfo.setApkName(apkName);
//得到程序的包名
String packageName = packageInfo.packageName;
appInfo.setApkPackageName(packageName);
//得到程序的资源文件夹
String sourceDir = packageInfo.applicationInfo.sourceDir;
File file = new File(sourceDir);
//得到apk的大小
long size = file.length();
appInfo.setApkSize(size);
System.out.println("---------------------------");
System.out.println("程序的名字:" + apkName);
System.out.println("程序的包名:" + packageName);
System.out.println("程序的大小:" + size);
//获取到安装应用程序的标记
int flags = packageInfo.applicationInfo.flags;
if ((flags & ApplicationInfo.FLAG_SYSTEM) != 0) {
//表示系统app
appInfo.setIsUserApp(false);
} else {
//表示用户app
appInfo.setIsUserApp(true);
}
if ((flags & ApplicationInfo.FLAG_EXTERNAL_STORAGE) != 0) {
//表示在sd卡
appInfo.setIsRom(false);
} else {
//表示内存
appInfo.setIsRom(true);
}
appInfos.add(appInfo);
}
return appInfos;
}
其中，安装包信息的bean类AppInfo代码为：
public class AppInfo {
private ApplicationInfo applicationInfo;
private int versionCode = 0;
private Drawable icon;
private String apkName;
private long apkSize;
private boolean isUserApp;
private boolean isRom;
private String apkPackageName;
... //此处省略setter和getter方法
｝
获取文档、压缩包、apk安装包等
private static ListgetFilesByType(int fileType) { List files = new ArrayList (); // 扫描files文件库 Cursor c = null; try { c = mContentResolver.query(MediaStore.Files.getContentUri("external"), new String[]{"_id", "_data", "_size"}, null, null, null); int dataindex = c.getColumnIndex(MediaStore.Files.FileColumns.DATA); int sizeindex = c.getColumnIndex(MediaStore.Files.FileColumns.SIZE); while (c.moveTonext()) { String path = c.getString(dataindex); if (FileUtils.getFileType(path) == fileType) { if (!FileUtils.isExists(path)) { continue; } long size = c.getLong(sizeindex); FileBean fileBean = new FileBean(path, FileUtils.getFileIconByPath(path)); files.add(fileBean); } } } catch (Exception e) { e.printStackTrace(); } finally { if (c != null) { c.close(); } } return files; }
传入的fileType文件类型是在FileUtils定义的文件类型声明：
public static final int TYPE_DOC = 0; public static final int TYPE_APK = 1; public static final int TYPE_ZIP = 2;
其中，FileUtils根据文件路径获取文件类型的方法getFileType(String path)为：
public static int getFileType(String path) {
path = path.toLowerCase();
if (path.endsWith(".doc") || path.endsWith(".docx") || path.endsWith(".xls") || path.endsWith(".xlsx")
|| path.endsWith(".ppt") || path.endsWith(".pptx")) {
return TYPE_DOC;
}else if (path.endsWith(".apk")) {
return TYPE_APK;
}else if (path.endsWith(".zip") || path.endsWith(".rar") || path.endsWith(".tar") || path.endsWith(".gz")) {
return TYPE_ZIP;
}else{
return -1;
}
}
文件的bean类FileBean代码为：
public class FileBean {
public String path;
public int iconId;
public FileBean(String path, int iconId) {
this.path = path;
this.iconId = iconId;
}
}
FileUtils根据文件类型获取图片资源id的方法，getFileIconByPath(path)代码为：
public static int getFileIconByPath(String path){
path = path.toLowerCase();
int iconId = R.mipmap.unknow_file_icon;
if (path.endsWith(".txt")){
iconId = R.mipmap.type_txt;
}else if(path.endsWith(".doc") || path.endsWith(".docx")){
iconId = R.mipmap.type_doc;
}else if(path.endsWith(".xls") || path.endsWith(".xlsx")){
iconId = R.mipmap.type_xls;
}else if(path.endsWith(".ppt") || path.endsWith(".pptx")){
iconId = R.mipmap.type_ppt;
}else if(path.endsWith(".xml")){
iconId = R.mipmap.type_xml;
}else if(path.endsWith(".htm") || path.endsWith(".html")){
iconId = R.mipmap.type_html;
}
return iconId;
}
上述各种文件类型的图片放置在mipmap中，用于展示文件列表时展示。
FileManager以及其他类的源码，可以点击下面的网址跳转查看和下载：
点击查看源码(phone目录下的文件)
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持考高分网。
