android 檢測該包名所對應的應用是否存在

/**
  	 * 檢測該包名所對應的應用是否存在
  	 * @param packageName
  	 * @return
  	 */
  	public boolean checkPackage(String packageName) 
  	{  
	    if (packageName == null || "".equals(packageName))  
	        return false;  
	    try 
	    {  
	        getPackageManager().getApplicationInfo(packageName, PackageManager.GET_UNINSTALLED_PACKAGES);  
	        return true;  
	    } 
	    catch (NameNotFoundException e) 
	    {  
	        return false;  
	    }  
	}