【文章內(nèi)容簡介】 Some properties must be set, not as text but as on/off values or through calls to special functions. For on/off, the value of 1 and 0 are used. The ForeColor property is an example of a property that needs a function to covert names to values (., red, green, blue) for the color. 24 of 69 Code Setting 8 Properties of a Text Display ? 13. Examine this example. It sets 8 parameters representing 57600 (4x4x5x2x2x3x6x10) possible possible variations of the stimulus in 8 lines of code. (Note this is example ) 25 of 69 Code ? Code Exercise 2 Properties Study Questions Could you at this point set properties of objects? 1. Change the font to bold? 2. Change background colors of the display? 3. Set the X position of the Fixation display to be the same as the Probe? Short Answers are included in the Exercise Appendix 26 of 69 Code Exercise 3 Execution Control Execution flow control allows repetitive actions or conditional actions. In this example we will use a For statement for a repetitive action and an IF statement for conditional actions. If x 10 Action True Action False For counter = Start to End Loop Action 27 of 69 Code Exercise 3 Execution Control For counter = Start to End If x 10 Action True Loop Action If x 10 Action True Examine the code note the: ? For next loop ? IF conditions The indenting shows the mands in the for loop. 28 of 69 Code Load and Execute ? 1. Open CodeExercise3 from My Documents\My Experiments\Workshop\EPrime Exercises\. ? 2. Examine the InLine1 code. Note it is CodeExercise1 with a For and If statements. ? 3. Run the program see the moving box 29 of 69 Code Add an IF Then ? 4. Add the IF Else statements shown ? If begins the conditional execution ? Then is the true action ? Else the False Action ? End IF finishes the If Note the ments explain the mod function to get a remainder and the CColor to set the color 30 of 69 Code Run Program With If Then ? 5. Run the program. Observe the color change. ?6. Change the maximum of the For and add ElseIf instead of Else for 3 states. 31 of 69 Code Run Program ? 7. Run program examine results. ? 8 Save program as 32 of 69 Code ? Code Exercise 3 Program Control Questions Could you at this point? 1. Add a loop to present the square in CodeExercise3ProgramControl to make the square move up for 1000 iterations, down and be a circle for 1000 iterations, and move horizontally and be an oval. 2. Find other program control mands and implement a While…When, Do…Loop or Case process. 3. Specify how to leave a For loop early (not covered in exercise but in lecture). Short Answers are included in the Exercise Appendix 33 of 69 Code Code Exercise 4. Use of Code to Set the Stimulus Conditional on a List Attribute This example uses the “Condition” variable to set the “Stim” variable to a random number and the “Resp” variable to the expected key. This also checks for errors in the typing of the attributes. 34 of 69 Code Open Code Examine Get Attribute ? 1. Open CodeExercise4 from My Documents\My Experiments\Workshop\EPrime Exercises\. 2. Examine the code and list and predict what will occur. 35 of 69 Code Run And Check for Error ? 3. Run the experiment ? Note you will see a message box appear on the last trial to indicate that a coding error has occurred, hit enter. This is intentional to illustrate self checking code. ?In this case the Bad Condition = bxlow indicates that a spelling error has been detected in the Condition. 36 of 69 Code Correct Errors ? 5. Open List1 and edit bxlow to below. Before After 37 of 69 Code Edit RandomNumberGenerate ? 6. Open RandomNumberGenerate and edit the conditions to select a number for below 14, above 69. Before After 38 of 69 Code Edit Instructions ? 7. Edit display instructions located on the Fixation display. Before After 39 of 69 Code Run and Test Program ? 8. Save as . ? 9. Run to test the program, note the random numbers selected are now between 19.