advertisement
Working with Projects
2.5 Maneuvering Objects with the
Touch Screen
Operator panels with touch screens do not have a built-in keyboard. All maneuvering is done with the touch screen by pressing distinctly with a finger.
Because of the resistive touch technology, the screen can only apprehend pressing on one place on the panel at the time. Pressing two points at the same time is interpreted by the panel as a point midway between the two pressed points.
Related information
2.5.1
Operate Objects
For an object to react, it is necessary to specify the behavior, typically by assigning a tag and defining an action. All objects can have actions linked to mouse down, mouse up, mouse enter and mouse leave events. Some objects have a predefined behavior, like sliders setting values, but can also have actions linked to mouse down and mouse up events.
Button
Pressing a button triggers a click- and mouse button event.
Text Box
Pressing on a text box object displays a virtual alpha-numeric keyboard on the panel screen. Type a text using this keyboard and finish by pressing [
ENTER
].
Analog Numeric
Pressing on an analog numeric object displays a virtual keyboard on the panel screen. The keyboard type depends on the format chosen for the Analog Numeric
— String, Integer, Decimal, Hex or Binary. Enter a value using this keyboard and finish by pressing [
ENTER
].
In runtime a validation of the value is done. If the value entered is out of bounds, the corresponding limit value for the object will be shown.
Slider
Pressing on the desired value position of a slider object sets it to the pressed position.
Related information
Beijer Electronics, MAEN831H
31
advertisement
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project