Android获取文件的mimeType的封装

概述

MIME(Multipurpose Internet Mail Extensions)多用途互联网邮件扩展类型。是设定某种扩展名的文件用一种应用程序来打开的方式类型，当该扩展名文件被访问的时候，浏览器会自动使用指定应用程序来打开。多用于指定一些客户端自定义的文件名，以及一些媒体文件打开方式。

步骤

1.定义各种文件对应的mimeType的xml文件

在res目录下面创建一个xml文件夹,在此文件夹下面创建对应xml文件

<?xml version="1.0" encoding="utf-8"?>
<MimeTypes>
<type extension=".png" mimetype="image/png" />
<type extension=".gif" mimetype="image/gif" />
<type extension=".jpg" mimetype="image/jpeg" />
<type extension=".jpeg" mimetype="image/jpeg" />
<type extension=".bmp" mimetype="image/bmp" />
<type extension=".mp2" mimetype="audio/x-mpeg" />
<type extension=".mp3" mimetype="audio/mp3" />
<type extension=".wav" mimetype="audio/wav" />
<type extension=".ogg" mimetype="audio/x-ogg" />
<type extension=".mid" mimetype="audio/mid" />
<type extension=".midi" mimetype="audio/midi" />
<type extension=".m3u" mimetype="audio/x-mpegurl" />
<type extension=".m4a" mimetype="audio/mp4a-latm" />
<type extension=".m4b" mimetype="audio/mp4a-latm" />
<type extension=".m4p" mimetype="audio/mp4a-latm" />
<type extension=".mpga" mimetype="audio/mpeg" />
<type extension=".wma" mimetype="audio/x-ms-wma" />
<type extension=".mpe" mimetype="video/mpeg" />
<type extension=".mpg" mimetype="video/mpeg" />
<type extension=".mpeg" mimetype="video/mpeg" />
<type extension=".3gp" mimetype="video/3gpp" />
<type extension=".asf" mimetype="video/x-ms-asf" />
<type extension=".avi" mimetype="video/x-msvideo" />
<type extension=".m4u" mimetype="video/vnd.mpegurl" />
<type extension=".m4v" mimetype="video/x-m4v" />
<type extension=".mov" mimetype="video/quicktime" />
<type extension=".mp4" mimetype="video/mp4" />
<type extension=".rmvb" mimetype="video/*" />
<type extension=".wmv" mimetype="video/*" />
<type extension=".vob" mimetype="video/*" />
<type extension=".mkv" mimetype="video/*" />
<type extension=".jar" mimetype="application/java-archive" />
<type extension=".zip" mimetype="application/zip" />
<type extension=".rar" mimetype="application/x-rar-compressed" />
<type extension=".gz" mimetype="application/gzip" />
<type extension=".gtar" mimetype="application/x-gtar" />
<type extension=".tar" mimetype="application/x-tar" />
<type extension=".tgz" mimetype="application/x-compressed" />
<type extension=".z" mimetype="application/x-compressed" />
<type extension=".htm" mimetype="text/html" />
<type extension=".html" mimetype="text/html" />
<type extension=".php" mimetype="text/php " />
<type extension=".txt" mimetype="text/plain" />
<type extension=".c" mimetype="text/plain" />
<type extension=".conf" mimetype="text/plain" />
<type extension=".cpp" mimetype="text/plain" />
<type extension=".h" mimetype="text/plain" />
<type extension=".java" mimetype="text/plain" />
<type extension=".log" mimetype="text/plain" />
<type extension=".prop" mimetype="text/plain" />
<type extension=".rc" mimetype="text/plain" />
<type extension=".sh" mimetype="text/plain" />
<type extension=".csv" mimetype="text/csv" />
<type extension=".xml" mimetype="text/xml" />
<type extension=".apk" mimetype="application/vnd.android.package-archive" />
<type extension=".bin" mimetype="application/octet-stream" />
<type extension=".class" mimetype="application/octet-stream" />
<type extension=".exe" mimetype="application/octet-stream" />
<type extension=".mpc" mimetype="application/vnd.mpohun.certificate" />
<type extension=".msg" mimetype="application/vnd.ms-outlook" />
<type extension=".doc" mimetype="application/msword" />
<type extension=".docx" mimetype="application/msword" />
<type extension=".js" mimetype="application/x-javascript" />
<type extension=".pdf" mimetype="application/pdf" />
<type extension=".pps" mimetype="application/vnd.ms-powerpoint" />
<type extension=".ppt" mimetype="application/vnd.ms-powerpoint" />
<type extension=".pptx" mimetype="application/vnd.ms-powerpoint" />
<type extension=".wps" mimetype="application/vnd.ms-works" />
<type extension=".rtf" mimetype="application/rtf" />
<type extension=".xls" mimetype="application/vnd.ms-excel" />
<type extension=".xlsx" mimetype="application/vnd.ms-e
c76b
xcel" />
</MimeTypes>

2.代码实现

可直接copy使用,详情请看注释

package com.geely.mars.sqldemo.tools;

import android.content.Context;
import android.content.pm.PackageManager;
import android.content.res.XmlResourceParser;
import android.text.TextUtils;
import com.geely.mars.sqldemo.R;
import org.xmlpull.v1.XmlPullParserException;
import java.io.IOException;
public class MimeTypesTools {

private static boolean hasLoadMimeType = false;

/**
*
* @param context
* @param fileName
* @return 获取文件mime类型
*/
public static String getMimeType(Context context, String fileName) {
if (!TextUtils.isEmpty(fileName)) {
fileName = fileName.toLowerCase();

MimeTypes mimeTypes = getMimeTypes(context);
String extension = getSuffix(fileName);
return mimeTypes.getMimeType(extension);
}

return null;
}

/**
* 获取文件格式的后缀名  如 .jpg
* @param uri 指定文件
* @return 如 .jpg
*/
public static String getSuffix(String uri) {
if (uri == null) {
return null;
}

int dot = uri.lastIndexOf(".");
if (dot >= 0) {
return uri.substring(dot);
} else {
// No extension.
return "";
}
}

private static MimeTypes getMimeTypes(Context context) {
return loadMimeTypes(context);
}

/**
* 解析xml 文件
* @param context
* @return
*/
private static MimeTypes loadMimeTypes(Context context) {
MimeTypeParser parser = null;
XmlResourceParser xmlResourceParser = null;
if (!hasLoadMimeType) {
try {
parser = new MimeTypeParser(context, context.getPackageName());
xmlResourceParser = context.getResources().getXml(R.xml.mimetypes);

return parser.fromXmlResource(xmlResourceParser);
} catch (XmlPullParserException e) {
e.printStackTrace();
} catch (PackageManager.NameNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
hasLoadMimeType = true;
}

return null;
}
}

package com.geely.mars.sqldemo.tools;

import android.content.Context;
import android.content.pm.PackageManager.NameNotFoundException;
import android.content.res.Resources;
import android.content.res.XmlResourceParser;

import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlPullParserFactory;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

public class MimeTypeParser {

public static final String TAG_MIMETYPES = "MimeTypes";
public static final String TAG_TYPE = "type";

public static final String ATTR_EXTENSION = "extension";
public static final String ATTR_MIMETYPE = "mimetype";
public static final String ATTR_ICON = "icon";

private XmlPullParser mXpp;
private MimeTypes mMimeTypes;
private Resources resources;
private String packagename;

public MimeTypeParser(Context ctx, String packagename) throws NameNotFoundException {
this.packagename = packagename;
resources = ctx.getPackageManager().getResourcesForApplication(packagename);
}

public MimeTypes fromXml(InputStream in)
throws XmlPullParserException, IOException {
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();

mXpp = factory.newPullParser();
mXpp.setInput(new InputStreamReader(in));

return parse();
}

public MimeTypes fromXmlResource(XmlResourceParser in)
throws XmlPullParserException, IOException {
mXpp = in;

return parse();
}

/**
* 对xml文件的解析
* @return
* @throws XmlPullParserException
* @throws IOException
*/
public MimeTypes parse()
throws XmlPullParserException, IOException {

mMimeTypes = new MimeTypes();

int eventType = mXpp.getEventType();

while (eventType != XmlPullParser.END_DOCUMENT) {
String tag = mXpp.getName();

if (eventType == XmlPullParser.START_TAG) {
if (tag.equals(TAG_MIMETYPES)) {

} else if (tag.equals(TAG_TYPE)) {
addMimeTypeStart();
}
} else if (eventType == XmlPullParser.END_TAG) {
if (tag.equals(TAG_MIMETYPES)) {

}
}

eventType = mXpp.next();
}

return mMimeTypes;
}

private void addMimeTypeStart() {
String extension = mXpp.getAttributeValue(null, ATTR_EXTENSION);
String mimetype = mXpp.getAttributeValue(null, ATTR_MIMETYPE);
String icon = mXpp.getAttributeValue(null, ATTR_ICON);

if(icon != null){
int id = resources.getIdentifier(icon.substring(1) , null, packagename);
if(id > 0){
mMimeTypes.put(extension, mimetype, id);
return;
}
}

mMimeTypes.put(extension, mimetype);
}

}

package com.geely.mars.sqldemo.tools;

import android.webkit.MimeTypeMap;

import java.util.HashMap;
import java.util.Map;

public class MimeTypes {

private Map<String, String> mMimeTypes;
private Map<String, Integer> mIcons;

public MimeTypes() {
mMimeTypes = new HashMap<String,String>();
mIcons = new HashMap<String,Integer>();
}

/* I think the type and extension names are switched (type contains .png, extension contains x/y),
* but maybe it's on purpouse, so I won't change it.
*/
public void put(String type, String extension, int icon){
put(type, extension);
mIcons.put(extension, icon);
}

public void put(String type, String extension) {
// Convert extensions to lower case letters for easier comparison
extension = extension.toLowerCase();

mMimeTypes.put(type, extension);
}

public String getMimeType(String filename) {

String extension =MimeTypesTools.getExtension(filename);

// Let's check the official map first. Webkit has a nice extension-to-MIME map.
// Be sure to remove the first character from the extension, which is the "." character.
if (extension.length() > 0) {
String webkitMimeType = MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension.substring(1));

if (webkitMimeType != null) {
// Found one. Let's take it!
return webkitMimeType;
}
}

// Convert extensions to lower case letters for easier comparison
extension = extension.toLowerCase();

String mimetype = mMimeTypes.get(extension);

if(mimetype==null) {
mimetype = "*/*";
}

return mimetype;
}

public int getIcon(String mimetype){
Integer iconResId = mIcons.get(mimetype);
if(iconResId == null) {
return 0; // Invalid identifier
}
return iconResId;
}
}

应用

如跳转到支持打开指定文件格式的系统应用

try {
Intent intent = new Intent();
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.setAction(android.content.Intent.ACTION_VIEW);
String type = MimeTypesTools.getMimeType(context, path);
File file = new File(path);
//添加这一句表示对目标应用临时授权该Uri所代表的文件
intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
if (file != null) {
Uri uri = null;
if (Build.VERSION.SDK_INT >= 24) {

uri = FileProvider.getUriForFile(context, context.getPackageName()+".fileprovider", file);
} else {
uri = Uri.fromFile(file);
}
if (uri != null) {
intent.setDataAndType(uri, type);
context.startActivity(intent);
}
}
} catch (Exception e) {
e.printStackTrace();
ToastUtil.show("手机上无可打开此格式的app");

}