kbruch/src/exercisecompare.cpp

   1 /***************************************************************************
   2                              exercisecompare.cpp
   3                              -------------------
   4     begin                : 2004/06/03
   5     copyright            : (C) 2004 by Sebastian Stein
   6     email                : seb.kde@hpfsc.de
   7  ***************************************************************************/
   8
   9 /***************************************************************************
  10  *                                                                         *
  11  *   This program is free software; you can redistribute it and/or modify  *
  12  *   it under the terms of the GNU General Public License as published by  *
  13  *   the Free Software Foundation; either version 2 of the License, or     *
  14  *   (at your option) any later version.                                   *
  15  *                                                                         *
  16  ***************************************************************************/
  17
  18 #include "exercisecompare.h"
  19 #include "exercisecompare.moc"
  20
  21 /* these includes are needed for KDE support */
  22 #include <kapplication.h>
  23 #include <klocale.h>
  24
  25 /* these includes are needed for Qt support */
  26 #include <qlabel.h>
  27 #include <qlayout.h>
  28 #include <qpushbutton.h>
  29 #include <qtooltip.h>
  30 #include <qwhatsthis.h>
  31
  32 /* standard C++ library includes */
  33 #include <stdlib.h>
  34
  35 /* ----- public member functions ----- */
  36
  37 /* constructor */
  38 ExerciseCompare::ExerciseCompare(QWidget * parent, const char * name):
  39                 ExerciseBase(parent, name)
  40 {
  41 #ifdef DEBUG
  42         kdDebug() << "constructor ExerciseCompare()" << endl;
  43 #endif
  44
  45         /* create a new task */
  46         QApplication::setOverrideCursor(waitCursor); /* show the sand clock */
  47         createTask();
  48         QApplication::restoreOverrideCursor(); /* show the normal cursor */
  49
  50         // the next thing to do on a button click would be to check the entered
  51         // result
  52         m_currentState = _CHECK_TASK;
  53
  54         baseWidget = new QWidget(this, "baseWidget");
  55         baseGrid = new QGridLayout(this, 1, 1, 0, -1, "baseGrid");
  56         baseGrid->addWidget(baseWidget, 0, 0);
  57
  58         // this is a VBox
  59         realLayout = new QVBoxLayout(baseWidget, 5, 5, "realLayout");
  60
  61         // add a spacer at the top of the VBox
  62         QSpacerItem * v_spacer = new QSpacerItem(1, 1);
  63         realLayout->addItem(v_spacer);
  64
  65         // now a line holding the task, input fields and result
  66         QHBoxLayout * taskLineHBoxLayout = new QHBoxLayout(5, "taskLineHBoxLayout");
  67         realLayout->addLayout(taskLineHBoxLayout);
  68
  69         // spacer
  70         v_spacer = new QSpacerItem(1, 1);
  71         taskLineHBoxLayout->addItem(v_spacer);
  72
  73         // first the first ratio widget
  74         m_firstRatioWidget = new RatioWidget(baseWidget, "m_firstRatioWidget", m_firstRatio);
  75         taskLineHBoxLayout->addWidget(m_firstRatioWidget);
  76
  77         // spacer
  78         v_spacer = new QSpacerItem(1, 1);
  79         taskLineHBoxLayout->addItem(v_spacer);
  80
  81         // now the button where the user has to choose the comparison sign
  82         m_signButton = new QPushButton(baseWidget, "m_signButton");
  83         m_signButton->setText("<");
  84         m_signButtonState = lessThen;
  85         taskLineHBoxLayout->addWidget(m_signButton);
  86         QObject::connect(m_signButton, SIGNAL(clicked()), this, SLOT(slotSignButtonClicked()));
  87         QToolTip::add(m_signButton, i18n("Click on this button to change the comparison sign."));
  88
  89         // spacer
  90         v_spacer = new QSpacerItem(1, 1);
  91         taskLineHBoxLayout->addItem(v_spacer);
  92
  93         // now the second ratio widget
  94         m_secondRatioWidget = new RatioWidget(baseWidget, "m_secondRatioWidget", m_secondRatio);
  95         taskLineHBoxLayout->addWidget(m_secondRatioWidget);
  96
  97         // spacer
  98         v_spacer = new QSpacerItem(1, 1);
  99         taskLineHBoxLayout->addItem(v_spacer);
 100
 101         // at the right end we have a label just showing CORRECT or WRONG
 102         result_label = new QLabel(baseWidget, "result_label");
 103         result_label->setText(i18n("WRONG"));
 104         taskLineHBoxLayout->addWidget(result_label);
 105         result_label->hide();
 106
 107         // --- that is the end of the horizontal line ---
 108
 109         // add another spacer in the middle of the VBox
 110         v_spacer = new QSpacerItem(1, 1);
 111         realLayout->addItem(v_spacer);
 112
 113         // the lower part of the VBox holds just a right aligned button
 114         QHBoxLayout * lowerHBox = new QHBoxLayout(1, "lowerHBox");
 115         realLayout->addLayout(lowerHBox);
 116         lowerHBox->addStretch(100);
 117
 118         // the right aligned button
 119         m_checkButton = new QPushButton( baseWidget, "m_checkButton" );
 120         m_checkButton->setText(i18n("&Check Task"));
 121         m_checkButton->setDefault(true); // is the default button of the dialog
 122         QToolTip::add(m_checkButton, i18n("Click on this button to check your result."));
 123         lowerHBox->addWidget(m_checkButton, 1, Qt::AlignRight);
 124         QObject::connect(m_checkButton, SIGNAL(clicked()), this, SLOT(slotCheckButtonClicked()));
 125
 126         // that the user can start typing without moving the focus
 127         m_signButton->setFocus();
 128
 129         // show the whole layout
 130         baseWidget->show();
 131
 132         // add tooltip and qwhatsthis help to the widget
 133         QToolTip::add(this, i18n("In this exercise you have to compare 2 given fractions."));
 134         QWhatsThis::add(this, i18n("In this exercise you have to compare 2 given fractions by choosing the correct comparison sign. You can change the comparison sign by just clicking on the button showing the sign."));
 135 }
 136
 137 /* destructor */
 138 ExerciseCompare::~ExerciseCompare()
 139 {
 140 #ifdef DEBUG
 141         kdDebug() << "destructor ExerciseCompare()" << endl;
 142 #endif
 143
 144         /* no need to delete any child widgets, Qt does it by itself */
 145 }
 146
 147 /** resets the current state, creates a new task and count the last task as
 148  * wrong, if it wasn't solved (in _NEXT_TASK state) yet
 149  * mainly used after changing the task parameters */
 150 void ExerciseCompare::forceNewTask()
 151 {
 152 #ifdef DEBUG
 153         kdDebug() << "forceNewTask ExerciseCompare()" << endl;
 154 #endif
 155
 156         if (m_currentState == _CHECK_TASK)
 157         {
 158                 // emit the signal for wrong
 159                 signalExerciseSolvedWrong();
 160         }
 161         m_currentState = _CHECK_TASK;
 162         m_checkButton->setText(i18n("&Check Task"));
 163
 164         // generate next task
 165         (void) nextTask();
 166 }
 167
 168
 169 /* ------ public slots ------ */
 170
 171 void ExerciseCompare::update()
 172 {
 173         // call update of components
 174         m_firstRatioWidget->updateAndRepaint();
 175         m_secondRatioWidget->updateAndRepaint();
 176
 177         // update for itself
 178         ((QWidget *) this)->update();
 179 }
 180
 181
 182 /* ------ private member functions ------ */
 183
 184 void ExerciseCompare::createTask()
 185 {
 186         // generate the first ratio
 187         m_firstRatio = ratio(int((double(rand()) / RAND_MAX) * 10 + 1), int((double(rand()) / RAND_MAX) * 10 + 1));
 188
 189         // now the second ratio, but make sure, the second ratio is different from
 190         // the first one
 191         do
 192         {
 193                 m_secondRatio = ratio(int((double(rand()) / RAND_MAX) * 10 + 1), int((double(rand()) / RAND_MAX) * 10 + 1));
 194         } while (m_firstRatio == m_secondRatio);
 195
 196         return;
 197 }
 198
 199 /**     - checks, if the user solved the task correctly
 200                 - emits signals if task was solved correctly or wrong */
 201 void ExerciseCompare::showResult()
 202 {
 203         QPalette pal;
 204         QColorGroup cg;
 205         bool result = m_firstRatio < m_secondRatio;
 206
 207         // change the tooltip of the check button
 208         QToolTip::add(m_checkButton, i18n("Click on this button to get to the next task."));
 209
 210         // disable sign button
 211         m_signButton->setEnabled(false);
 212
 213         if ((m_signButtonState == lessThen && result == true) ||
 214                  (m_signButtonState == greaterThen && result == false))
 215         {
 216                 // emit the signal for correct
 217                 signalExerciseSolvedCorrect();
 218
 219                 /* yes, the user entered the correct result */
 220                 result_label->setText(i18n("CORRECT"));
 221                 pal = result_label->palette(); /* set green font color */
 222                 cg = pal.active();
 223                 cg.setColor(QColorGroup::Foreground, QColor(6, 179, 0));
 224                 pal.setActive(cg);
 225                 cg = pal.inactive();
 226                 cg.setColor(QColorGroup::Foreground, QColor(6, 179, 0));
 227                 pal.setInactive(cg);
 228                 result_label->setPalette(pal);
 229                 result_label->show(); /* show the result at the end of the task */
 230         } else {
 231                 // emit the signal for wrong
 232                 signalExerciseSolvedWrong();
 233
 234                 /* no, the user entered the wrong result */
 235                 result_label->setText(i18n("WRONG"));
 236                 pal = result_label->palette(); /* set red font color */
 237                 cg = pal.active();
 238                 cg.setColor(QColorGroup::Foreground, QColor(red));
 239                 pal.setActive(cg);
 240                 cg = pal.inactive();
 241                 cg.setColor(QColorGroup::Foreground, QColor(red));
 242                 pal.setInactive(cg);
 243                 result_label->setPalette(pal);
 244
 245                 result_label->show(); /* show the result at the end of the task */
 246         } /* if (entered_result == result) */
 247
 248         return;
 249 }
 250
 251 /** generate the next task and show it to the user */
 252 void ExerciseCompare::nextTask()
 253 {
 254         // change the tooltip of the check button
 255         QToolTip::add(m_checkButton, i18n("Click on this button to check your result."));
 256
 257         // enable sign button
 258         m_signButton->setEnabled(true);
 259
 260         result_label->hide(); /* do not show the result at the end of the task */
 261
 262         // reset the signButton
 263         m_signButton->setText("<");
 264         m_signButtonState = lessThen;
 265
 266         /* create a new task */
 267         QApplication::setOverrideCursor(waitCursor); /* show the sand clock */
 268         createTask();
 269         QApplication::restoreOverrideCursor(); /* show the normal cursor */
 270
 271         // set the ratio widgets with the new ratios
 272         m_firstRatioWidget->setRatio(m_firstRatio);
 273         m_secondRatioWidget->setRatio(m_secondRatio);
 274
 275         return;
 276 }
 277
 278 /* ------ private slots ------ */
 279
 280 void ExerciseCompare::slotCheckButtonClicked()
 281 {
 282         if (m_currentState == _CHECK_TASK)
 283         {
 284                 m_currentState = _NEXT_TASK;
 285                 m_checkButton->setText(i18n("N&ext Task"));
 286                 (void) showResult();
 287         } else {
 288                 m_currentState = _CHECK_TASK;
 289                 m_checkButton->setText(i18n("&Check Task"));
 290                 (void) nextTask();
 291         }
 292
 293         return;
 294 }
 295
 296 void ExerciseCompare::slotSignButtonClicked()
 297 {
 298         if (m_signButtonState == lessThen)
 299         {
 300                 m_signButton->setText(">");
 301                 m_signButtonState = greaterThen;
 302         } else {
 303                 m_signButton->setText("<");
 304                 m_signButtonState = lessThen;
 305         }
 306
 307         return;
 308 }