Page Comparison

{alias:qblockedtrace}
h2. Name

*qblockedtrace* — connect widget and Tcl variable

h2. Syntax
{panel:|borderStyle=solid|borderWidth=1|bgColor=#FFFFAA}
*qblockedtrace* \[_widget_] _variable_

{panel}

h2. Description

The *qblockedtrace* command assigns a trace variable to a current widget. A trace variable will at all times reflect the state or contents of the widget to which it is assigned. Writing to the variable will update the widget accordingly. 

{note}
Assigning a value to a trace variable created with *qblockedtrace* will not result in the widget's callback function being called. To achieve this use [qtrace] 
{note}
 

See [qtrace] for a further description on how variable tracing works. 

h2. Arguments

_widget_
{indent}The widget to which the variable will be connected. If this argument is omitted the current widget will be used. 
{indent}

_variable_
{indent}The name of the traced variable. The variable should be global or exist in a namespace. When referring to a namespace variable the namespace name should be part of the argument, like "MyNamespace::my_variable". 
{indent} 


{pagebreak}