Android根据文件后缀名选择外部打开方式

项目应用本身只集成了腾讯浏览插件，只能打开基本文档类型，其他类型的文件通过手机其他应用打开，
直接使用http://www.cnblogs.com/hibraincol/archive/2010/09/16/1828502.html的方法发现Android7无法正常打开，这里注意需要使用fileprovider,代码中的xxx.provider要自己设置

if (Build.VERSION.SDK_INT >= 24) {
    uri = FileProvider.getUriForFile(mContext, "xxx.provider",file);
} else {
    uri = Uri.fromFile(file);
}

具体如下

public class OpenFileUtil {
    private static OpenFileUtil instance = null;

    private OpenFileUtil() {
    }

    public static OpenFileUtil getInstance() {
        synchronized (OpenFileUtil.class) {
            if (instance == null) {
                instance = new OpenFileUtil();
            }
        }

        return instance;
    }

    /**
     * 根据文件后缀名获得对应的MIME类型。
     *
     * @param file
     */
    private String getMIMEType(File file) {
        String type = "*/*";
        String fName = file.getName();
        //获取后缀名前的分隔符"."在fName中的位置。
        int dotIndex = fName.lastIndexOf(".");
        if (dotIndex < 0) {
            return type;
        }
        /* 获取文件的后缀名 */
        String end = fName.substring(dotIndex, fName.length()).toLowerCase();
        if (end.equals("")) return type;
        //在MIME和文件类型的匹配表中找到对应的MIME类型。
        for (int i = 0; i < MIME_MapTable.length; i++) {
            if (end.equals(MIME_MapTable[i][0]))
                type = MIME_MapTable[i][1];
        }
        return type;
    }

    /**
     * 打开文件
     *
     * @param file
     */
    public void openFile(Context mContext, File file) {
        try {
            Uri uri;
            if (Build.VERSION.SDK_INT >= 24) {
                uri = FileProvider.getUriForFile(mContext, "xxx.provider",file);
            } else {
                uri = Uri.fromFile(file);
            }
            Intent intent = new Intent(Intent.ACTION_VIEW);
            intent.addCategory(Intent.CATEGORY_DEFAULT);
            intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
            intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            intent.setDataAndType(uri, getMIMEType(file));
            mContext.startActivity(intent);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    //建立一个MIME类型与文件后缀名的匹配表
    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"},
            {".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"},
            {".prop", "text/plain"},
            {".rar", "application/x-rar-compressed"},
            {".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/xml"},
            {".xml", "text/plain"},
            {".z", "application/x-compress"},
            {".zip", "application/zip"},
            {"", "*/*"}
    };
}