How to set mobile input types in HTML?

Mobile devices have virtual keyboards. There is only limited space on the display to show the keyboard, so it will be helpful to the user to see only the needed keys. Using the right input type will dramatically improve the mobile experience.

There are many different input types available for html pages. Here are my favorites.

Input type text

The most common input type used. This will show the default keyboard on mobile devices.

Input type email

The input type email will show a virtual keyboard with easy access to the AT-Sign (@), the dot and sometimes there will be shown the most common top level domains, so you don’t have to enter “.com” letter by letter. The difference to the text input type is only marginal, but the mobile user experience will increase dramatically if you use the input type on the right field.

Input type tel

With the input type tel you can make it easy to enter a telephone number because you will get a virtual keyboard with a numeric keypad which includes everything you need to enter a phone number like sharp (#) or plus (+).

Input type number

The mobile input type “number” is correct if you have to enter numbers only. It is different from the input type tel and is the right type to enter numbers of barcodes, counters or anything else mainly containing digits but i think this type shouldn’t be using very often because in most cases tel will work better.

Input type password

If you ever made a login form you should know about it and I don’t want to describe it here, because there are millions of good descriptions about this input type in the World Wide Web.

Input type date

The name of the input type is date and this is what you can enter here. You don’t have to implement a JavaScript calendar widget or something else. Just set the tags attribute type to date and the mobile will do the rest for you. I like it.

Input type datetime

It is like the input type date, but it adds the time to the input. So you can enter date and time into your input field. Just replace the tag attrubte type from date to datetime and you have a input field for date and time.

Input type search

If your input field is a search field, you can use this type. It will show the (nearly) regular virtual keyboard with on exception. You get a search button direct on the virtual keyboard if you use this mobile input type. It is quite helpful and I use it often if I need a search function in my form.

Note: Some devices and virtual keyboards do not support every mobile input type. But If you user iOS or Android with a common keyboard, I’m sure you will get the right keyboard for your input type. And there are more…. but the above are the main types (IMHO).

Disable text selection with CSS

Yes, it is possible to disable the text selection with a simple line of CSS.

The user-select property is a new CSS3 property. Using user-select enables web and app developers to control the ability to select text. Most browsers (With CSS3 support), can do this by using variations on the CSS3 user-select property. The user-select property controls the actual Selection operation (Text and Images). This won’t have effect on the visible content, except in textboxes. The content of the element and all sub-elements will not be able to be selected.

For IE < 10 and Opera, you will need to use the unselectable attribute of the element you wish to be unselectable. You can set this using an attribute in HTML. But this property isn't inherited to child elements, meaning you have to put the unselectable attribute in the start tag of every element inside the tag.

At least there is a additional JavaScript solution for the IE.

Note: Disable text selection with CSS is non-standard and is not on a standards track. Avoid using it on production sites facing the Web. It will not work for every user.


How to get the version of your Android application from AndroidManifest.xml?

There are two parts of the version in AndroidManifest.xml.

  • android:versionCode
  • android:versionName

In your AndroidManifest.xml the versionCode is a number, and every version you want to submit to google play needs to have a higher number then the last. VersionName is just a string, and can be anything you want it to be. In VersionName you can define your app as “1.0” or “” or “Test Version” or whatever.

To get the android:versionCode and the android:versionName you can use the following code snippet where context is your actual context. If you execute this code in your Activity you can remove the “context.” from “context.getPackageManager()”. Because the Activity is a indirect Subclasses of Context.

Note: Other known Subclasses of Context are:


If you are not in in a class that is a subclass of Context you have to identify your context to get the version from your AndroidManifest.xml.

Remove uncommitted changes from your working directory in GIT

There is a easy solution to remove all uncommitted changes from your working directory in GIT

Note: After executing this command, all uncommitted changes will be removes from your working directory. If you want to save the current work before removing all uncommitted changes, you can do:

Now your work is saved on the branch “backup” in case you decide you want to backup your work to look at it later or diff it.


Capture screenshot in Java (AWT)

In Java there is a easy was to capture screenshots. The following captureScreenshot method will capture a screenshot of the display of your screen and save it to the disk.

If you want to create a screenshot of a specific part of your screen, you have to modyfy the rectangle. You can do this with rectangle .setBounds(int x, int y, int width, int height).

Rectangle API:

Note: This will need “java.awt”. So you cannot run this code on Android devices, because there is no java.awt package available. Also note, that you have to run a X-Server on linux to execute this. If you try to execute this on a linux server without X-Server, you will not be able to capture screenshot of your terminal.
On Windows this is not a problem. The capture screenshot method will work on windows even if you are not the Administrator.

How to get the name of the current method in Java

There is a simple solution, to get the name of the current method in Java. It uses the stack trace to get the name of the mehod. It works with different virtual machines like oracle, dalvik (Android), Open JDK, etc.

But don’t use this in time-critical code, because working with the StackTrace is not recommended for high performcnce activities.


How to create random human readable passwords in PHP

To generate random readable passwords you can combine words, letters and special chars. The words can come from a wordlist array. For example you can use the list of the 10,000 most common English words in order of frequency, as determined by n-gram frequency analysis of the Google’s Trillion Word Corpus.

In the exmaple the words are taken from a static array, but you can use the google-10000-english.txt file with the php file() function which reads an entire file into an array. The generated password will contain one or more of the words in the list, depending on the length parameter. If you execute

you will get a random readable password with a length of 10 chars, but you can adjust the parameter to get a password with a different length.


Android Background Service Template

This is a simple Android background Service Template. You can use it to run updates in the background without blocking the UI. To start and stop the service use the following lines in your activity:

This is all you need to execute a service on android devices. Don’t forget to add the service to your AndroidManifest.xml file.

Connect the esp8266 to the wireless network

For the IoT you can use a cheap esp8266 microcontroller with WiFi onboard. To connect the esp8266 to the wireless network you can use the following lua snippet that will work with the nodemcu firmware.

After connecting to the internet, you can create a TCP/IP server or client to send and receive data from your esp8266 microcontroller.

How to use LIMIT and ORDER BY in sqlite

To get the first 10 in descending order in sqlite

To get the first 10 in ascending order in sqlite

Note: If there are less than 10 entrys in the sqlite database, you will get less than 10 results.