Tutorials & Examples

Random Numbers.
Timer.
ExitApplication.

 

Service Module using CallSub.

A very simple example. I thought you had to use CallSub from an Activity, but had it backwards.

 

NOTE: there may be a way to achieve this already in B4A that I'm not aware of.

This little tutorial will show you how to create an app with translucent status bar And/Or navigation keys...

 

If you build an app which uses a larger form you might have realized this by pairs of labels and edittexts. The label ist used for the description (f.e. "Name") and the edittext will contain the...

 

Here's a quick little example of how to shorten your urls using tinyurl.com.

Thanks to TDS, who provided the solution.

 

ie: If you want to make a music control widget

First you need to add a broadcast listener to the manifest

AddReceiverText(thenameofyourservice,
<intent-filter>
<action...

 

This project demonstrates grayscaling of a multi colored image and then the binarization (i.e black or white pixels only) of the grayscaled image. The binarization is based on Otsu Thresholding as...

 

This project demonstrates dithering of 8 bit grayscale images as explained at www.fiji.sc/Dithering. Methods included are the following:

Floyd-Steinberg
Atkinson
Jarvis-Judice-Ninke
Stucki...

 

This project demonstrates the conversion of RGB images to various options of Grayscale images. It is based on the tutorial at http://www.tannerhelland.com/3643/

Click on any one of the...

 

This project demonstrates contrast enhancement of low contrast Grayscale images based on Histogram Equalization as explained at...

 

Hello,
This app is a sample to get GPS info, save into file, load list of tracks, show in map,
assign a photo and send map and log info in CSV format by email.
Also there is some code about saving...

 

We'll do this using the Canvas object.

I'm just learning but pretending that I can teach it

Download the provided CanvasTest.zip and open it.

What I've done here is to create a panel and...

 

I have a new toy

The attached AbstractLayout.txt file includes the layouts of the Samsung Galaxy Nexus, the first Android 4.0 device.
You should copy it to Basic4android installation folder...

 

I wanted to provide this simple code for beginners like me.
The code is derived from the one written by the my teacher Klaus here.

This ListView is made with a ScrollView inside of which is...

 

The following code draws a "selection" window when you move the finger:

Sub Globals
    Dim Canvas1 As Canvas
    Dim Rect1 As Rect
    Dim sx, sy As Int
End Sub

Sub Activity_Create(FirstTime...

 

There are situations where we change the panel colors, like when the user select its own color, and we dont know if the text of the labels will be seen. Commonly we define black or white for text...

 

Hi,

normaly B4A use UTF8 encoding, but can create files in ANSI too, but be carefull !
Windows an a Western PC use ANSI codepage 1252, this is in B4A "WINDOWS-1252".
Mostly the encoding...

 

The attached project shows the use of the USB library to communicate with Midi Devices over USB. I realize that this may open a can of worms, as it seems nothing about Midi communication is...

 

The attached project will generate the Reed Solomon generator polynomials for 7, 10, 13, 15, 16, 17, 18, 20, 22, 24, 26, 28, and 30 error correction words that might be required for QR codes as...

 

Works fine but the timer keeps cutting off in my rather big and complex app.... oh well I'll have to figure that out then.

Still perhaps useful to some.

You send it a number of milliseconds like...