kalarm/pickfileradio.cpp

   1 /*
   2  *  pickfileradio.cpp  -  radio button with an associated file picker
   3  *  Program:  kalarm
   4  *  Copyright © 2005,2009 by David Jarvie <djarvie@kde.org>
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License along
  17  *  with this program; if not, write to the Free Software Foundation, Inc.,
  18  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  19  */
  20
  21 #include "kalarm.h"
  22 #include "pickfileradio.h"
  23
  24 #include "buttongroup.h"
  25 #include "lineedit.h"
  26
  27 #include <QPushButton>
  28 #include <QTimer>
  29 #include "kalarm_debug.h"
  30
  31
  32 PickFileRadio::PickFileRadio(QPushButton* button, LineEdit* edit, const QString& text, ButtonGroup* group, QWidget* parent)
  33     : RadioButton(text, parent),
  34       mGroup(group),
  35       mEdit(Q_NULLPTR),
  36       mLastButton(Q_NULLPTR),
  37       mRevertButton(false)
  38 {
  39     Q_ASSERT(parent);
  40     init(button, edit);
  41 }
  42
  43 PickFileRadio::PickFileRadio(const QString& text, ButtonGroup* group, QWidget* parent)
  44     : RadioButton(text, parent),
  45       mGroup(group),
  46       mEdit(Q_NULLPTR),
  47       mButton(Q_NULLPTR),
  48       mLastButton(Q_NULLPTR),
  49       mRevertButton(false)
  50 {
  51     Q_ASSERT(parent);
  52 }
  53
  54 void PickFileRadio::init(QPushButton* button, LineEdit* edit)
  55 {
  56     Q_ASSERT(button);
  57     if (mEdit)
  58         mEdit->disconnect(this);
  59     mEdit   = edit;
  60     mButton = button;
  61     mButton->setEnabled(false);
  62     connect(mButton, &QPushButton::clicked, this, &PickFileRadio::slotPickFile);
  63     if (mEdit)
  64     {
  65         mEdit->setEnabled(false);
  66         connect(mEdit, &LineEdit::textChanged, this, &PickFileRadio::fileChanged);
  67     }
  68     connect(mGroup, &ButtonGroup::buttonSet, this, &PickFileRadio::slotSelectionChanged);
  69     setReadOnly(RadioButton::isReadOnly());
  70 }
  71
  72 void PickFileRadio::setReadOnly(bool ro)
  73 {
  74     RadioButton::setReadOnly(ro);
  75     if (mButton)
  76     {
  77         if (mEdit)
  78             mEdit->setReadOnly(ro);
  79         if (ro)
  80             mButton->hide();
  81         else
  82             mButton->show();
  83     }
  84 }
  85
  86 void PickFileRadio::setFile(const QString& file)
  87 {
  88     mFile = file;
  89 }
  90
  91 QString PickFileRadio::file() const
  92 {
  93     return mEdit ? mEdit->text() : mFile;
  94 }
  95
  96 /******************************************************************************
  97 * Set the radio button enabled or disabled.
  98 * Adjusts the enabled/disabled state of other controls appropriately.
  99 */
 100 void PickFileRadio::setEnabled(bool enable)
 101 {
 102     Q_ASSERT(mButton);
 103     RadioButton::setEnabled(enable);
 104     enable = enable  &&  mGroup->checkedButton() == this;
 105     if (enable)
 106     {
 107         if (!pickFileIfNone())
 108             enable = false;    // revert to previously selected type
 109     }
 110     mButton->setEnabled(enable);
 111     if (mEdit)
 112         mEdit->setEnabled(enable);
 113 }
 114
 115 /******************************************************************************
 116 * Called when the selected radio button changes.
 117 */
 118 void PickFileRadio::slotSelectionChanged(QAbstractButton* button)
 119 {
 120     if (button == mLastButton  ||  mRevertButton)
 121         return;
 122     if (mLastButton == this)
 123     {
 124         mButton->setEnabled(false);
 125         if (mEdit)
 126             mEdit->setEnabled(false);
 127     }
 128     else if (button == this)
 129     {
 130         if (!pickFileIfNone())
 131             return;    // revert to previously selected type
 132         mButton->setEnabled(true);
 133         if (mEdit)
 134             mEdit->setEnabled(true);
 135     }
 136     mLastButton = button;
 137 }
 138
 139 /******************************************************************************
 140 * Prompt for a file name if there is none currently entered.
 141 */
 142 bool PickFileRadio::pickFileIfNone()
 143 {
 144     if (mEdit)
 145         mFile = mEdit->text();
 146     if (!mFile.isEmpty())
 147         return true;
 148     return !slotPickFile().isEmpty();
 149 }
 150
 151 /******************************************************************************
 152 * Called when the file picker button is clicked.
 153 * Reply = mFile, or null string if dialogue, and 'this', was deleted.
 154 */
 155 QString PickFileRadio::slotPickFile()
 156 {
 157     // To avoid crashes on application quit, we need to check whether the
 158     // dialogue, and hence this PickFileRadio, was deleted while active,
 159     // before accessing class members.
 160     QString file = pickFile();
 161     if (file.isNull())
 162         return file;   // 'this' is probably invalid now
 163     if (!file.isEmpty())
 164     {
 165         mFile = file;
 166         if (mEdit)
 167             mEdit->setText(mFile);
 168     }
 169     if (mFile.isEmpty())
 170     {
 171         // No file is selected, so revert to the previous radio button selection.
 172         // But wait a moment before setting the radio button, or it won't work.
 173         mRevertButton = true;   // prevent picker dialog popping up twice
 174         QTimer::singleShot(0, this, &PickFileRadio::setLastButton);
 175     }
 176     return mFile;
 177 }
 178
 179 /******************************************************************************
 180 * Select the previously selected radio button in the group.
 181 */
 182 void PickFileRadio::setLastButton()
 183 {
 184     if (!mLastButton)
 185         setChecked(false);    // we don't know the previous selection, so just turn this button off
 186     else
 187         mLastButton->setChecked(true);
 188     mRevertButton = false;
 189 }
 190
 191 // vim: et sw=4: