android用于打开各种文件的intent

import android.app.Activity;  import android.content.Intent;  import android.net.Uri;  import android.net.Uri.Builder;  import java.io.File;  import android.content.Intent;  //自定义android Intent类，  //可用于获取打开以下文件的intent  //PDF,PPT,WORD,EXCEL,CHM,HTML,TEXT,AUDIO,VIDEO  示例:  //这个不行，可能是因为PDF.apk程序没有权限访问其它APK里的asset资源文件,又或者是路径写错?  //Intent it = getPdfFileIntent("file:///android_asset/helphelp.pdf");  //下面这些都OK  //Intent it = getHtmlFileIntent("/mnt/sdcard/tutorial.html");//SD卡主目录  //Intent it = getHtmlFileIntent("/sdcard/tutorial.html");//SD卡主目录,这样也可以  Intent it = getHtmlFileIntent("/system/etc/tutorial.html");//系统内部的etc目录  //Intent it = getPdfFileIntent("/system/etc/helphelp.pdf");  //Intent it = getWordFileIntent("/system/etc/help.doc");  //Intent it = getExcelFileIntent("/mnt/sdcard/Book1.xls")  //Intent it = getPptFileIntent("/mnt/sdcard/download/Android_PPT.ppt");//SD卡的download目录下  //Intent it = getVideoFileIntent("/mnt/sdcard/ice.avi");  //Intent it = getAudioFileIntent("/mnt/sdcard/ren.mp3");  //Intent it = getImageFileIntent("/mnt/sdcard/images/001041580.jpg");  //Intent it = getTextFileIntent("/mnt/sdcard/hello.txt",false);  startActivity( it );  public class MyIntent  {   //android获取一个用于打开HTML文件的intent    public static Intent getHtmlFileIntent( String param )    {      Uri uri = Uri.parse(param ).buildUpon().encodedAuthority("com.android.htmlfileprovider").scheme("content").encodedPath(param ).build();      Intent intent = new Intent("android.intent.action.VIEW");      intent.setDataAndType(uri, "text/html");      return intent;    }   //android获取一个用于打开图片文件的intent    public static Intent getImageFileIntent( String param )    {      Intent intent = new Intent("android.intent.action.VIEW");      intent.addCategory("android.intent.category.DEFAULT");      intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);      Uri uri = Uri.fromFile(new File(param ));      intent.setDataAndType(uri, "image/*");      return intent;    }    //android获取一个用于打开PDF文件的intent    public static Intent getPdfFileIntent( String param )    {      Intent intent = new Intent("android.intent.action.VIEW");      intent.addCategory("android.intent.category.DEFAULT");      intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);      Uri uri = Uri.fromFile(new File(param ));      intent.setDataAndType(uri, "application/pdf");      return intent;    }   //android获取一个用于打开文本文件的intent   public static Intent getTextFileIntent( String param, boolean paramBoolean)   {   Intent intent = new Intent("android.intent.action.VIEW");    intent.addCategory("android.intent.category.DEFAULT");   intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);   if (paramBoolean)   {  Uri uri1 = Uri.parse(param );   intent.setDataAndType(uri1, "text/plain");   }   else   {  Uri uri2 = Uri.fromFile(new File(param ));  intent.setDataAndType(uri2, "text/plain");   }   return intent;  }   //android获取一个用于打开音频文件的intent    public static Intent getAudioFileIntent( String param )    {      Intent intent = new Intent("android.intent.action.VIEW");      intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);    intent.putExtra("oneshot", 0);      intent.putExtra("configchange", 0);      Uri uri = Uri.fromFile(new File(param ));      intent.setDataAndType(uri, "audio/*");      return intent;    }    //android获取一个用于打开视频文件的intent    public static Intent getVideoFileIntent( String param )    {       Intent intent = new Intent("android.intent.action.VIEW");      intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);      intent.putExtra("oneshot", 0);      intent.putExtra("configchange", 0);      Uri uri = Uri.fromFile(new File(param ));      intent.setDataAndType(uri, "video/*");      return intent;    }    //android获取一个用于打开CHM文件的intent    public static Intent getChmFileIntent( String param )    {       Intent intent = new Intent("android.intent.action.VIEW");      intent.addCategory("android.intent.category.DEFAULT");      intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);      Uri uri = Uri.fromFile(new File(param ));      intent.setDataAndType(uri, "application/x-chm");      return intent;    }   //android获取一个用于打开Word文件的intent     public static Intent getWordFileIntent( String param )    {       Intent intent = new Intent("android.intent.action.VIEW");       intent.addCategory("android.intent.category.DEFAULT");       intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);       Uri uri = Uri.fromFile(new File(param ));       intent.setDataAndType(uri, "application/msword");       return intent;     }   //android获取一个用于打开Excel文件的intent     public static Intent getExcelFileIntent( String param )     {       Intent intent = new Intent("android.intent.action.VIEW");       intent.addCategory("android.intent.category.DEFAULT");       intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);       Uri uri = Uri.fromFile(new File(param ));       intent.setDataAndType(uri, "application/vnd.ms-excel");       return intent;     }   //android获取一个用于打开PPT文件的intent     public static Intent getPptFileIntent( String param )     {       Intent intent = new Intent("android.intent.action.VIEW");       intent.addCategory("android.intent.category.DEFAULT");       intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);       Uri uri = Uri.fromFile(new File(param ));       intent.setDataAndType(uri, "application/vnd.ms-powerpoint");       return intent;     }  }