The most spread method to connect to a remote MySQL database from an android device, is to put some kind of service into the middle. Since MySQL is usually used together with PHP, the easiest and most obvious way to write a PHP script to manage the database and run this script using HTTP protocol from the android system.
We can code the data in JSON format, between Android and PHP with the easy to use built in JSON functions in both languages.
I present some sample code, which selects data from a database depending on a given condition and creates a log message on the android side with the received data.
Lets suppose that we have a MySQL database named PeopleData, and a table int created, with the following SQL:
As described in the previous part, we will use a Service to update the appWidget.
So we will have the Service below, which gets the command (right now we have only the update command), ant the appwidgetId, reads the date from sharedPreferences and updates the widget.
I just come to a new discovery regarding widgets. I was developing an appwidget, which - just like the widgets we are trying to make in this series of tutorials - and tried it out multiple phones. Unfortunatelly on one of our test phones it didn't function properly. For random intervals it stopped to refresh, and it din't responded to button presses on the widget, only after 1-2 minutes. After hard work I discivered the following:
Buttons on appwiget can have their onclick flunctionality thorough RemoteViews.setOnClickPendingIntent(). This method gets a PendingIntent ap parametes to bound to a button. PendingIntent's can have 3 types created with
getActivity(Context, int, Intent, int)
In this tutorial we will show you how you can easily debug a service.
Introduction
When you start a project with a service in it in debug mode, and you placed a breakpoint in a method of the service, the debugger will not stop.
Solution
The solution that works in almost all situation is to wait declaratively in the code for the debugger to attach. To do this, you have to make a call to:
android.os.Debug.waitForDebugger();
The breakpoint can be inserted at any line after this call.
As a complete example, the SoftKeyboard tutorial is enhanced with the call above:
As you can see in the code, the first call in the method is a call to the logger, with which we can see in the Log output when our method was called. This can be an other way of tracking our method calls, without the need to stop at a breakpoint. But usually this is not enough for detailed debugging.
Then the second statement waits for the debugger to attach, as it is also noted in the comment. After this line the breakpoint can be inserted anywhere in the method.
Debugging a Service in case an Activity is also part of the application is even easier. In that case the activity has to be started first, then the debugger is able to stop at the breakpoint in the service as well, without the need of an explicit waitForDebugger() call.
Introduction
