android：如何从我的应用程序打开另一个应用程序？

android: how do i open another app from my app?

提问by mtmurdock

I understand how to use intents and startActivity() when opening another activity within my own app, but how do you start a different app? specifically:

我了解在我自己的应用程序中打开另一个 Activity 时如何使用 Intent 和 startActivity()，但是如何启动不同的应用程序？具体来说：

• How do you determine if the user has the needed app installed on their device?
• How do you start that app?
• How do you pass parameters to that app?
• How do you find all this info out for a specific app (say Adobe reader, or google maps)?

• 您如何确定用户是否在其设备上安装了所需的应用程序？
• 你如何启动那个应用程序？
• 您如何将参数传递给该应用程序？
• 您如何找到特定应用程序（例如 Adob​​e 阅读器或谷歌地图）的所有这些信息？

回答by Tim Kryger

How to see if Intent is available:

如何查看 Intent 是否可用：

1. Try calling Intent and deal with ActivityNotFoundExceptionif it isn't available

   Intent intent = new Intent(Intent.ACTION_VIEW);
   intent.setDataAndType(path, "application/pdf");
   intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
   
   try {
       startActivity(intent);
   } 
   catch (ActivityNotFoundException e) {
       Toast.makeText(OpenPdf.this, 
           "No Application Available to View PDF", 
           Toast.LENGTH_SHORT).show();
   }
   

   or

2. Query the Package Managerto see if it is ahead of time:

   PackageManager packageManager = getPackageManager();
   Intent intent = new Intent(Intent.ACTION_VIEW);
   intent.setType("application/pdf");
   
   List list = packageManager.queryIntentActivities(intent,
       PackageManager.MATCH_DEFAULT_ONLY);
   
   if (list.size() > 0) {
       intent.setDataAndType(path, "application/pdf");
       startActivity(intent);
   }
   

1. 尝试调用 Intent 并处理ActivityNotFoundException它是否不可用

   Intent intent = new Intent(Intent.ACTION_VIEW);
   intent.setDataAndType(path, "application/pdf");
   intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
   
   try {
       startActivity(intent);
   } 
   catch (ActivityNotFoundException e) {
       Toast.makeText(OpenPdf.this, 
           "No Application Available to View PDF", 
           Toast.LENGTH_SHORT).show();
   }
   

   或者

2. 查询包管理器看是否提前：

   PackageManager packageManager = getPackageManager();
   Intent intent = new Intent(Intent.ACTION_VIEW);
   intent.setType("application/pdf");
   
   List list = packageManager.queryIntentActivities(intent,
       PackageManager.MATCH_DEFAULT_ONLY);
   
   if (list.size() > 0) {
       intent.setDataAndType(path, "application/pdf");
       startActivity(intent);
   }
   

How to pass parameters to an application or know its capabilities:

如何将参数传递给应用程序或了解其功能：

1. List of Available Intents for Google Applications
2. List of Intents by 3rd parties @ OpenIntents

1. Google 应用程序的可用 Intent 列表
2. 第 3 方 @ OpenIntents 的意图列表

回答by HXCaine

What you are looking for are intentsand intent filters.

您正在寻找的是意图和意图过滤器。

Everything you want to know is detailed on the Android developer guide.

您想知道的一切都在 Android 开发人员指南中详细说明。

http://developer.android.com/guide/topics/intents/intents-filters.html

http://developer.android.com/guide/topics/intents/intents-filters.html