Rapid Application Design with the ROOT GUI Classes

1
Rapid Application Design with the ROOT GUI Classes
Ilka Antcheva, Bertrand Bellenot, René Brun, Fons
Rademakers, Valeriy Onuchin
CERN, Geneva, Switzerland IHEP, Protvino, Russia
24 April 2007
2
Overview

• Main Features
• Benefits from Using CINT
• Application Design
• Signals Slots
• Scripting
• C Code Generation
• Dialogs
• GUI Builder
• Automatic Context Menus
• External Applications
• Conclusions

3
Main Features

• ROOT GUI classes form a rich and complete set of
  widgets
• Fully cross platform with the same look and feel
  on either Unix, Linux, Windows and Mac OS X
• Fully scriptable allowing fast prototyping via
  the embedded CINT C interpreter
• The GUI builder (under development) makes the
  task of designing complex GUIs easier and faster
• High level GUIs in ROOT the browser, tree
  viewer, graphics editor, fit panel, session
  viewer of PROOF, etc.

4
Benefits from Using CINT

• Prototyping via the CINT C interpreter
• Supports from simple sequence of statements to
  complex C class and method definitions
• Remove edit compile cycle
• Macros can be edited and re-executed
• Transparent interface to native C compiler to
  run macro with native machine performance

root 0 .x myDialog.C root 1
root 0 .x myDialog.C root 1 .x myDialog.C
fText new TGTextEntry(fMain, new
TGTextBuffer(100)) fText-gtSetToolTipText("En
ter the label and hit Enter key")
fText-gtConnect("ReturnPressed()", "MyDialog",
this, "DoSetlabel()") fMain-gtAddFrame(fText,
new TGLayoutHints(kLHintsTop kLHintsLeft, 5,
5, 5, 5)) fGframe new TGGroupFrame(fMain,
"Last File") fLabel new TGLabel(fGframe,
"No Intut ") fGframe-gtAddFrame(fLabel, new
TGLayoutHints(kLHintsTop kLHintsLeft, 5, 5, 5,
5)) fMain-gtAddFrame(fGframe, new
TGLayoutHints(kLHintsExpandX, 2, 2, 1, 1))

// fText new TGTextEntry(fMain, new
TGTextBuffer(100)) // fText-gtSetToolTipText("En
ter the label and hit Enter key") //
fText-gtConnect("ReturnPressed()", "MyDialog",
this, "DoSetlabel()") // fMain-gtAddFrame(fText,
new TGLayoutHints(kLHintsTop kLHintsLeft, 5,
5, 5, 5)) fGframe new TGGroupFrame(fMain,
"Last File") fLabel new TGLabel(fGframe,
"No Intut ") fGframe-gtAddFrame(fLabel, new
TGLayoutHints(kLHintsTop kLHintsLeft, 5, 5, 5,
5)) fText new TGTextEntry(fGframe, new
TGTextBuffer(100)) fText-gtSetToolTipText("En
ter the label and hit Enter key")
fText-gtConnect("ReturnPressed()", "MyDialog",
this, "DoSetlabel()") fText-gtResize(150,
fText-gtGetDefaultHeight())
fGframe-gtAddFrame(fText, new TGLayoutHints(kLHints
Top kLHintsLeft, 5, 5, 5, 5))
fMain-gtAddFrame(fGframe, new TGLayoutHints(kLHints
ExpandX, 2, 2, 1, 1))
5
Application Design

• Map user requirements and logically organize the
  GUI
• Application window is handled by TGMainFrame
• Select widgets from ROOT GUI classes
• Layout the GUI components
• Parent-children relationship
• Different layout managers
• Program them to perform actions
• Signal/slot mechanism
• Conventional model of event processing
• Run and validate or iterate to improve

6
Signals Slots

• Signal/Slot communication mechanism is integrated
  into ROOT core by TQObject, TQConnection, TQClass
• Uses dictionary information and the CINT
  interpreter to connect signal methods to slot
  methods
• Total independence
  of the
  interacting classes (easy programming)

7
Scripting

• Macros via the ROOT Object Browser

8
More Scripting

• TGTextEditor - basic editor for compiling and
  executing macros

Drag Drop macros from the browser
9
C Code Generation

• Using ctrlS any GUI can be saved as a C macro
  file thanks to the SavePrimitive methods
  implemented in all GUI classes.
• The generated macro can be modified and executed
• It restores the complete original GUI and all
  existing signal/slot connections

root 0 .x example.C
10
Dialogs

• Standard set of common dialogs

• Files selection (multiple files)

• Input dialog
• Message window
• Search dialog
• Print dialog

TGFileInfo fi new TGFileDialog(fClient-gtGetDefaul
tRoot(), this, kFDOpen,fi) if
(fi.fMultipleSelection fi.fFileNamesList)
TObjString el TIter next(fi.fFileNamesList)
while ((el (TObjString ) next()))
new TFile(el-gtGetString(), "update") else
if (fi.fFilename) new TFile(fi.fFilename,
"update")
11
More Dialogs
// Change background color via color
selector. TGFrame fr TGColorDialog cd
GetGlobalColorDialog() cd-gtSetCurrentColor(fr-gt
GetBackground()) cd-gtConnect("ColorSelected(Pix
el_t)", "TGFrame", fr,
ChangeBackground(Pixel_t)") fClient-gtWaitForUnm
ap(cd) TQObjectDisconnect(cd)
// Change text font via font selection
dialog. TGGroupFrame gfr TGFontDialog fd
GetGlobalFontDialog() TGResourcePool rc
gcfClient-gtGetResourcePool() TGGC gc
rc-gtGetGCPool()-gtFindGC(fr-gtGetNormGC())
TGFont font 0 Font rc-gtGetFontPool()-gtFind
Font(fr-gtGetFontStruct()) fd-gtSetColor(gc-gtGetF
oreground()) fd-gtSetFont(font)
fd-gtConnect("FontSelected(char)",
"TGGroupFrame", gfr, "SetTextFont(char)")
fd-gtConnect("ColorSelected(Pixel_t)",
"TGGroupFrame", gfr, "SetTextColor(Pixel_t)")
fClient-gtWaitForUnmap(fd) TQObjectDisconnec
t(fd)
12
Complex Dialogs
13
GUI Builder

• Visual design without coding
• Design process
• Mainly based on Drag Drop
• Flexible layout settings
• Ends up as C source code reflecting
  parents-children relationship
• Establish signal/slot connections and their
  concrete implementation (to be done)

14
Automatic Context Menus

• Context sensitive popup menu
• Automatically generated by ROOT
• Gives direct access to class member functions
• Any context menu can be retrieved
• Can be extended with user- defined entries

TClass cl Graph-gtIsA() TList mnl
cl-gtGetMenuList()
15
External Applications

• TCanvas can be embedded into any 3rd party GUI
  environment when it is possible to
• Obtain a Window ID (XID on X11, HWND on Windows)
• Create a timer to handle ROOT events
• Forward events to the ROOT canvas

ROOT
16
Conclusions

• The ROOT GUI classes form a rich and powerful
  scriptable cross-platform GUI library
• Solid basis for the development of additional
  GUIs help browser, object editors, fit panel,
  event displays
• The GUI builder makes designing GUIs easier
• Easy application distribution by storing the
  GUIs with data in the same ROOT file
• The future - to provide users with access through
  multiple interfaces from any location, with any
  device at any time.