Tag Archives: open source

GMap.NET component : Moving Marker

WTH is GMap.NET?

Simply put: it’s an open source .net component that can show online mapping service (such as Google Map, Bing Map, OpenStreetMap) in your .NET app.
Download the binary here: http://greatmaps.codeplex.com/
Extract it. You’ll get the .net 2.0 and .net 4.0 version, since I’m using VS 2015, we’ll use the .net 4.0 version.

What will we do now is about how to move a marker inside the map (for tracking/visualizing object movement, etc). We’ll just move the marker randomly in this tutorial.

  • Create new VB Windows Form project
  • Add GMap.NET component into your project reference
GMap.NET component reference

GMap.NET component reference

  • Add GMap.NET component into your toolbar.
Add GMap.NET component step 1

Add GMap.NET component step 1

Add GMap.NET component step 2

Add GMap.NET component step 2

  • Now drag and drop the GMap.NET control into your Form, I name it myMap
  • We’ll also add another controls: 1 Button (name: btnMove), 1 Timer (name: tmr1), 1 Label (name: lblInfo)
List of components

List of components

I also add new bitmap resource into our project properties. This will be used as our marker symbol.

Resource for marker symbol

Resource for marker symbol

You can see the Form’s full source code at the bottom of this post. I’ll just point out some important parts:

  • Map initialization is on Form1_Load event code (zoom level, initial position, provider used, marker type, etc)
  • When you click on the btnMove, it’ll start generating new random position for our marker. The random change is happened in the timer event (tmr1_Tick)
  • The process to update the map visual is delegated into function update_map(), so it will run in different thread and the form still responsive
  • In this tutorial, we are using BingSatelliteMapProvider, you can use another provider such as GoogleMapProvider or OviSatelliteMapProvider. Just see MapProviders namespace to see all supported providers.

Running the app

Running the app

Here’s the full source code:

CEntos 6.7 Migrating from mysql-server/mysql-community-server into latest MariaDB

Ok, first you should install yum-replace plugin if you haven’t already have it.

Get MariaDB packages repo from MariaDB repos builder here
MariaDB repo builder
You’ll get some repo config text that you can save to /etc/yum.repos.d/MariaDb.repo like these:

Do update your repo chache

If you’re installing mysql-server from CentOS 6.7 default repo, you should do this:

If you’re installing mysql server from webtatic repo (mysql55w-server), you should do this:

If you’re installing from MySQL Community repository, do this:

Just answer with ‘Y’ if the yum replace command show you some conflicts.
Next, just install all MariaDB related packages:

Start MariaDB:

Confirm that you’re using MariaDB:

Don’t worry, if you have successfully installing MariaDB over MySQL:

  1. your web app that use MySQL will not broken, no need to change anything
  2. your data will stay intact (no data loss)
  3. use MySQL commands as usual (such as: mysql -u root -p)
  4. the MariaDB config is still in /etc/my.cnf

In short, business as usual!

Exporting high resolution image from QGIS project



You want to export your QGIS project into high resolution image. QGIS desktop “Project” –> “Save as Image” only save/export the project into a low resolution image (i.e. your desktop resolution).



1. Finish your project in QGIS

Finish your GIS project in QGIS Desktop, choose which layers to be shown, what style should it use, etc.

2. Choose your extent that will be exported into image

For myself, I choose the full-extent, but you may choose the extent as you wish. You my use “Vector” –> “Coordinate Capture” to help copying the coordinates. You will need to write down the coordinates for [xMin, yMin] (top-left coordinate) and for [xMax, yMax] (bottom-right coordinate). Save and close your QGIS project.

3. Execute the export command via command line of QGIS

Open your command prompt/console (preferably as Administrator/root). Go to your QGIS binary folder, where you install QGIS +”bin” folder, for example C:\Program Files\QGIS Brighton\bin. Use this command template:

For example:

That command will open QGIS Desktop for a moment then close itself. The command will produce padangsari.png in c:\users\achmadz\documents\. Open the image, and you’ll see the image in high resolution (5000×5000 pixels).


Windows Installer Cleaner

Some background:

My SSD drive is almost full, after checking with TreeSize Free, it seems a lot of space is taken by files inside c:\windows\installer\. Searching around, I conclude that some of files is safe to be deleted from that particular place. There is a VB script in http://blogs.msdn.com/b/heaths/archive/2007/01/31/how-to-safely-delete-orphaned-patches.aspx that detect which files that shouldn’t be deleted from c:\windows\installer.

I also know an application named WiCleanup from KZTechs that detect and delete the “safe” files but after I tried it, the confirmation of deletion for files one-by-one makes me uncomfortable. So, I decide, why not programming the application by myself? And this application is born!


I programmed the application in VB .NET language using the free Microsoft Visual Studio 2013 Community Edition. Without further a do, you can download the application here:

[button link=”http://www.ahowto.net/wp-content/uploads/2015/03/Release.zip”]Windows Installer Cleaner Binary Only[/button]
(Of course you need .NET framework 4.5 installed if you want to run this application)
[button link=”http://www.ahowto.net/wp-content/uploads/2015/03/wic_winform.zip”]Windows Installer Cleaner Full Source Code[/button]

How to use:

It’s quite straight forward. There are three buttons there, you just need to click on them sequentially.

  1. Click “Get Kept List” to see which files that you should keep on c:\windows\installer
  2. Click “Get Delete List” to get the files that should be safe to be deleted and their size.
  3. Click “Delete Files” to delete the detected files.

What I learn from building this application:

  • how to create .NET application that need Administrator privilege (UAC things) when executed
  • how to use COM object in .NET application
  • how to use/import .dll from MS Windows in .NET
  • some file operation in .NET (FileInfo, deleting files, file’s attribute)
Windows Installer Cleaner Screenshot in Windows 7 64-bit

Windows Installer Cleaner Screenshot in Windows 7 64-bit

The application is already tested on Windows 8.1 64-bit and Windows 7 SP1 64-bit. Both systems is running fine until now. 😀

Matrix operation library for CodeIgniter

This tips is useful if you someday handling web-based project that involving Matrix handling and you want to implement it using CodeIgniter. We’ll use PHPMath library for this.

  • Download the latest version of phpmath library from here: http://www.phpmath.com/build02/downloads/
  • Open the archive (build02.tar.gz) and see the content, you’ll see “build02” folder, go inside, you’ll see more folders there:
phpmath archive content

phpmath archive content

  • Because we only need the matrix handling and operation library, we just need the “JAMA” folder inside.
  • Extract this “JAMA” folder into your CodeIgniter’s application/third_party/ library, rename it to more meaningful folder, I prefer “phpmath”. Your third_party library will be look like this:
phpmath inside third_party folder

phpmath inside third_party folder

  • Go inside “phpmath” folder, you’ll see more folders there. We don’t need “docs”, “examples” and “tests” folder, we can delete them, your phpmath folder will be like this:
phpmath after deleting unnecessary folders

phpmath after deleting unnecessary folders

And you are done! (In this tips: not like mPDF and PHPExcel library, we don’t need to create a new file/class in the application/libraries folder)

How to use it?

Quite simple, check and test these code samples inside your controller: