SWMM5 Delphi GUI Dreport.pas Summary

 Below is an overview of Dreport.pas, a Delphi unit from SWMM 5.2 that defines a dialog (TReportSelectForm) for specifying the contents of various types of tabular or graphical reports. These include:

1. Time Series Plot
2. Scatter Plot
3. Table by Variable
4. Table by Object

Once the user makes selections (e.g., which objects, which variables, and date ranges), the form gathers this information into a TReportSelection record and calls MainForm.CreateReport(...) to generate the actual report or plot.

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1. Purpose and Context

In SWMM, the user can create several kinds of reports/plots:

• Time Series Plot: multiple objects vs. time.
• Scatter Plot: one variable on X-axis and another on Y-axis, for selected objects/dates.
• Table by Variable: a time series table (one variable for multiple objects).
• Table by Object: multiple variables for a single object.

TReportSelectForm is a stay-on-top form that prompts the user to choose:

• Object types (subcatchments, nodes, links, system).
• Which objects specifically (selected from the map or browser).
• Which variables to include.
• Which date/time range (start, end, possibly in elapsed or absolute time).
• Additional details (time axis style, maximum number of items, etc.).

Once user clicks OK, the form’s code packages all these choices into a TReportSelection structure. The main UI (MainForm) uses CreateReport(ReportSelection) to actually build or display the requested table or plot.

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2. Main Form: TReportSelectForm

2.1 Notable Controls and Tabs

1. Notebook1
   • A multi-page control. Depending on ReportTypeChoice, a specific page is shown:
     • Page 0: Time Series or Table-type selection (objects + variables).
     • Page 1: Scatter plot selection (X-axis, Y-axis).
2. CategoryCombo (or XCategoryCombo/YCategoryCombo for scatter)
   • Chooses the object class: subcatchments, nodes, links, or system.
3. VariableListBox
   • A check list box for variables. The user can select one or multiple.
4. ItemsListBox
   • A list box for the specific objects chosen. For instance, if it’s a time series plot, the user can pick multiple nodes or links.
5. Date Ranges
   • StartDateCombo1/2, EndDateCombo1/2: combo boxes listing simulation date/time steps.
   • For time series or scatter plots, user picks a start and end date index.
6. Add / Delete / MoveUp / MoveDown
   • Manage which objects appear in ItemsListBox.
7. XObjectEdit/YObjectEdit
   • For scatter plots, store the single X or Y object ID.
8. XVariableCombo/YVariableCombo
   • For scatter plots, which variable on X or Y axis.

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3. Process Flow

3.1 SetReportType(aReportType)

• Configures the form for a given report type:
  • TIMESERIESPLOT, SCATTERPLOT, TABLEBYVARIABLE, or TABLEBYOBJECT.
• The form’s Notebook1.PageIndex is set accordingly.
• Sets MaxObjects (the maximum number of objects the user can select).
• For tables/plots dealing with subcatchments/nodes/links, populates the relevant combos with their available variables.
• If the user is picking from system-level variables, the code also includes the “System” category.

3.2 CategoryComboClick / XCategoryComboClick / YCategoryComboClick

• When the user picks “Subcatchments,” “Nodes,” “Links,” or “System,” these routines fill the associated variable combos:
  • For subcatchments, fill from MainForm.SubcatchViewBox.Items (skipping the “(None)” item).
  • For nodes, from MainForm.NodeViewBox.Items.
  • For links, from MainForm.LinkViewBox.Items.
  • For system, from SysViewNames[].
• For time-series or table by variable, it also updates the ItemsListBox if the user is currently viewing a subcatch/node/link in the SWMM data browser.

3.3 AddToItemList

• When the user presses Add, the code retrieves the currently selected object in SWMM (CurrentList/CurrentItem) and appends its ID to ItemsListBox.

3.4 VariableListBoxClick

• In “Table by Variable” or “Time Series Plot,” we allow multiple variables if we’re dealing with system or “table by object,” otherwise only one.
• If multi-variable is not allowed, clicking one variable unchecks others.

3.5 BtnOKClick

1. Checks constraints:
   • Must have at least one variable selected (if needed).
   • Must have valid date range (StartDate <= EndDate).
   • Must not exceed MaxObjects.
2. If a scatter plot, ensures the user has valid Xobject, Yobject.
3. If valid, calls CreateReport to build a TReportSelection record with all the info, and calls MainForm.CreateReport(ReportSelection).

3.6 CreateReport

• Gathers user selections:
  • ReportType: determined by ReportTypeChoice.
  • ObjectType: subcatchments, nodes, links, or system.
  • StartDateIndex / EndDateIndex: from combos.
  • Items: from ItemsListBox (or if scatter, from XobjectEdit + YobjectEdit).
  • VariableCount / Variables[]: from VariableListBox or XVariableCombo / YVariableCombo.
  • Whether we use elapsed time or actual date/time.
• Then it calls MainForm.CreateReport(ReportSelection) to produce the final table or chart.

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4. Special Cases

1. System objects: The user can’t select multiple system “objects”—there’s only one system. Thus, ItemsListBox is hidden or disabled.
2. Table by Object: The user picks only one object in ItemsListBox, but can pick multiple variables in VariableListBox.

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5. Summary

Dreport.pas is the “front end” to SWMM’s tabular and plot reports. By collecting user choices about objects, variables, and date ranges, it forms a consistent approach for:

• Time series graphs (multiple objects, single or multiple variables).
• Scatter plots (two distinct objects/variables).
• Tabular reports (by variable or by object).

Finally, it invokes MainForm.CreateReport(ReportSelection) to generate the actual result. This design ensures consistent input validation and user flow across SWMM’s various reporting tools.