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The QIMEvent class provides parameters for input method events. More...
#include <qevent.h>
Inherits QEvent.
Input method events are send to widgets, when an input method is used to enter text into a widget. Input methods are widely used to enter text in Asian languages.
The events are of interest to widgets that accept keyboard input and want to be able to correctly handle Asian languages. Text input in Asian languages is usually a three step process. When the user presses the first key on a keyboard an input context is created. This input context will contain a string with the typed characters. With every new key pressed, the input method will try to create a matching string for the text typed so far.
While the input context is active, the user can move the cursor only inside the string belonging to this input context. At some point, when the user presses the Spacebar, they get to the second stage, where they can choose from a number of strings that match the text they have typed so far. The user can press Enter to confirm their choice or Escape to cancel the input; in either case the input context will be closed. Note that the particular key presses used for a given input context may differ from those we've mentioned here, i.e. they may not be Spacebar, Enter and Escape.
These three stages are represented by three different types of events. The IMStartEvent, IMComposeEvent and IMEndEvent. When a new input context is created, an IMStartEvent will be sent to the widget and delivered to the QWidget::imStartEvent() function. The widget can then update internal data structures to reflect this.
After this, an IMComposeEvent will be send to the widget with every key the user presses. It will contain the current composition string the widget has to show and the current cursor position within the composition string. This string is temporary and can change with every key the user types, so the widget will need to store the state before the composition started (the state it had when it received the IMStartEvent). IMComposeEvents will be delivered to the QWidget::imComposeEvent() function.
Usually, widgets try to mark the part of the text that is part of the current composition in a way that is visible to the user. Mostly this is achieved by using e.g. dotted underline.
After the user has selected the final string, and IMEndEvent will be sent to the widget. The event contains the final string the user selected. This string has to be accepted as the final text the user entered, and the intermediate composition string should be cleared. These events are delivered to QWidget::imEndEvent().
If the user clicks another widget, taking the focus out of the widget where the compose is taking place the IMEndEvent will be sent and the string it holds will be the result of the composition up to that point (which could be an empty string).
See also Event Classes.
Constructs a new QIMEvent with accept flag set to FALSE. type can be one of QEvent::IMStartEvent, QEvent::IMComposeEvents and QEvent::IMEndEvent. text contains the current compostion string and cursorPosition the current position of the cursor inside text.
Setting the accept parameter indicates that the receiver of the event processed the input method event.
The accept flag is not set by default.
See also ignore().
Returns the current cursor position inside the composition string. Will return 0 for IMStartEvent and IMEndEvent.
Clearing the accept parameter indicates that the event receiver does not want the input method event.
The accept flag is cleared by default.
See also accept().
Returns the composition text. This is a null string for an IMStartEvent, and contains the final accepted string in the IMEndEvent.
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