Virtual Keyboard

Published : 01-01-2015 by : Pawan Janorkar

Rating: 5/5 (11 votes)

Virtual Keyboard is a small Java application that lets you easily create multilingual text content on almost any existing platform and output it directly to web pages. Virtual Keyboard, being a small, handy, well-designed and easy to use application, turns into a perfect solution for cross platform multilingual text input.

The main features are: platform-independent multilingual support for keyboard text input, built-in language layouts and settings, copy/paste etc. operations support just as in a regular text editor, already existing system language settings remain intact, easy and user-friendly interface and design, and small file size.

Virtual Keyboard is available as Java applet and Java-script. It uses a special API to interact with a web page. You can invoke its public methods from Java script to perform certain tasks such as Launch Virtual Keyboard, Move the Virtual Keyboard window to exact screen coordinates, etc. The application also uses a bound text control to transfer the text to/from the page.

The key matrix is the grid of circuits underneath the keys. In all keyboards except for capacitive ones, each circuit is broken at the point below a specific key. Pressing the key, bridges the gap in the circuit, allowing a tiny amount of current to flow through. The processor monitors the key matrix for signs of continuity at any point on the grid. When it finds a circuit that is closed, it compares the location of that circuit on the key matrix to the character map in its ROM.

The character map is basically a comparison chart for the processor that tells it what the key at x,y coordinates in the key matrix represents. If more than one key is pressed at the same time, the processor checks to see if that combination of keys has a designation in the character map. For example, pressing the ‘a’ key by itself would result in a small letter "a" being sent to the computer. If you press and hold down the Shift key while pressing the ‘a’ key, the processor compares that combination with the character map and produces a capital letter "A."

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