Setting Breakpoints

In the above illustration the two breakpoints have already been set. To set these breakpoints:

Choose Edit > Go to line...
The Goto dialog appears.
To go to the line for the first breakpoint, type

90 in the Goto dialog and press Go to.
You are positioned at line 90 in the file.
To set the breakpoint, press Break At.
To set the second breakpoint, choose Edit > Go to line..., type 101 in the Goto dialog and press Go to.
You are positioned at line 101 in the file.
To set the breakpoint, press Break At.
Look at the code lines immediately preceding our two breakpoints. You can see that in each case constraint.gridheight has been assigned a value (1 and then 4).
After stopping the application at the first breakpoint, we will take a look at the variable's run-time value, then stop at the next breakpoint and use the Variable Viewer to verify that this value has been changed.