Day: April 12, 2010

According to Yahoo’s “Best Practices for Speeding Up your Site”, the pros for using iframes:

• Helps with slow third-party content like badges and ads
• Download scripts in parallel

but the cons are:

• Costly even if blank
• Blocks page onload

I want to use an iframe to load ads using the technique mentioned on this site:
http://meanderingpassage.com/2007/08/15/keeping-javascript-widgets-from-controlling-your-blog/

Does using this technique mean that as soon as the html contents requested by the iframe are returned to the client, it will load the ad script, potentially blocking the rest of the page’s rendering and downloading? Or will the iframe request get processed concurrently while rest of the document is downloaded and rendered?

I’m, however, not looking for a discussion on the philosophy of whether ads are good or bad.

Answer

Rendering of the interior iframe is processed concurrently with the exterior page. Any javascript inside the iframe will only prevent loading of the contents inside the iframe.

Edit: also, I just noticed I answered your previous question on this subject, and as explained there it’s possible to trigger iframe loading in javascript whenever you wish (e.g. after the rest of the page is loaded).

How do I check if a directory exist on the sdcard in android?

Answer

Regular Java file IO:

File f = new File(Environment.getExternalStorageDirectory() + "/somedir");
if(f.isDirectory()) {
   ....

Might also want to check f.exists(), because if it exists, and isDirectory() returns false, you’ll have a problem. There’s also isReadable()…

Check here for more methods you might find useful.

Strangely I find no support for Midi in Android.
The only thing that comes close is the Jetplayer, but this only takes a existing .jet file.

I want to dynamically generate a midi file with some intervals and play it.
I even thought about just manually creating a .jet file with a tone and then transposing it with the jet player, but it limits the transposing to -12, +12. Which is not so good for me.

There also is a ToneGenerator on Android, but it’s limited to predefined tones with no way to transpose.

Does someone know how to achieve midi generation and playback on Android?

Answer

Perhaps this Pragmatic Programmer thread might be of interest.

I have the following TextView in my XML layout file:-

<TextView  
   android:layout_width="fill_parent" 
       android:layout_height="wrap_content" 
       android:text="@string/autolink_test"
       android:autoLink="all"
/>

The string autolink_test contains a phone number, an email address, a website address and a physical geographical address.

While the first three are showing up correctly as clickable autolinks, the address does not. Only the zipcode part shows up as an autolink… and that too as a phone number! (When I click it, the phone dialer starts up with that number).

Any help would be appreciated.

Answer

OK, I figured out what was causing the problem. Just thought I will leave the answer here in case someone else runs into the same problem.

If the street address is not properly capitalized, it is not read properly as the address!

Here is my XML autolink_test string:

<string name="autolink_test">Name: New York Times n
   Email: public@nytimes.com n
   Phone: 212-556-7652 n
   Address: 620 Eighth Avenue New York, NY 10018  n
   Address: 620 Eighth avenue New York, NY 10018  n
   Website: http://www.nytimes.com
</string>

The first address shows up correctly as an autolink. The second one (with a small ‘a’ in ‘avenue’) does not show up correctly.

This seems a little strange to me as the google maps website certainly doesn’t care about such niceties.

Anyways, so here it is 🙂

which way to reload a current page (using a button) would you prefer?

1 <input type="button" value="Reload" onClick="history.go(0)">
2 <input type="button" value="Reload" onClick="location.reload(true)">
3 <input type="button" value="Reload" onClick="window.location.reload(true)">
4 <input type="button" value="Reload" onClick="window.location.href=window.location.href">
5 <input type="button" value="Reload" onClick="document.location.reload(true)">
6 <input type="button" value="Reload" onClick="document.location.href=document.location.href">

As the URL of the page changes frequently AFAIK a ‘fallback function’ like

<a href="urlOfCurrentPage.html" onclick="window.location.reload(true);return false;">Reload</a>

won’t work for me, right?

Answer

Depends on what you want to do. The fourth and sixth methods there won’t reload any form data, they essentially make a separate visit to the page. Some versions of Firefox also have issues with the third method. Other than that, I’d go with the fifth as a personal preference. It seems the clearest.