source/modules/juce_gui_basics/filebrowser/juce_ImagePreviewComponent.cpp

   1 /*
   2   ==============================================================================
   3
   4    This file is part of the JUCE library.
   5    Copyright (c) 2022 - Raw Material Software Limited
   6
   7    JUCE is an open source library subject to commercial or open-source
   8    licensing.
   9
  10    By using JUCE, you agree to the terms of both the JUCE 7 End-User License
  11    Agreement and JUCE Privacy Policy.
  12
  13    End User License Agreement: www.juce.com/juce-7-licence
  14    Privacy Policy: www.juce.com/juce-privacy-policy
  15
  16    Or: You may also use this code under the terms of the GPL v3 (see
  17    www.gnu.org/licenses).
  18
  19    JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
  20    EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
  21    DISCLAIMED.
  22
  23   ==============================================================================
  24 */
  25
  26 namespace juce
  27 {
  28
  29 ImagePreviewComponent::ImagePreviewComponent()
  30 {
  31 }
  32
  33 ImagePreviewComponent::~ImagePreviewComponent()
  34 {
  35 }
  36
  37 //==============================================================================
  38 void ImagePreviewComponent::getThumbSize (int& w, int& h) const
  39 {
  40     auto availableW = proportionOfWidth (0.97f);
  41     auto availableH = getHeight() - 13 * 4;
  42
  43     auto scale = jmin (1.0,
  44                        availableW / (double) w,
  45                        availableH / (double) h);
  46
  47     w = roundToInt (scale * w);
  48     h = roundToInt (scale * h);
  49 }
  50
  51 void ImagePreviewComponent::selectedFileChanged (const File& file)
  52 {
  53     if (fileToLoad != file)
  54     {
  55         fileToLoad = file;
  56         startTimer (100);
  57     }
  58 }
  59
  60 void ImagePreviewComponent::timerCallback()
  61 {
  62     stopTimer();
  63
  64     currentThumbnail = Image();
  65     currentDetails.clear();
  66     repaint();
  67
  68     FileInputStream in (fileToLoad);
  69
  70     if (in.openedOk() && fileToLoad.existsAsFile())
  71     {
  72         if (auto format = ImageFileFormat::findImageFormatForStream (in))
  73         {
  74             currentThumbnail = format->decodeImage (in);
  75
  76             if (currentThumbnail.isValid())
  77             {
  78                 auto w = currentThumbnail.getWidth();
  79                 auto h = currentThumbnail.getHeight();
  80
  81                 currentDetails
  82                     << fileToLoad.getFileName() << "\n"
  83                     << format->getFormatName() << "\n"
  84                     << w << " x " << h << " pixels\n"
  85                     << File::descriptionOfSizeInBytes (fileToLoad.getSize());
  86
  87                 getThumbSize (w, h);
  88
  89                 currentThumbnail = currentThumbnail.rescaled (w, h);
  90             }
  91         }
  92     }
  93 }
  94
  95 void ImagePreviewComponent::paint (Graphics& g)
  96 {
  97     if (currentThumbnail.isValid())
  98     {
  99         g.setFont (13.0f);
 100
 101         auto w = currentThumbnail.getWidth();
 102         auto h = currentThumbnail.getHeight();
 103         getThumbSize (w, h);
 104
 105         const int numLines = 4;
 106         auto totalH = 13 * numLines + h + 4;
 107         auto y = (getHeight() - totalH) / 2;
 108
 109         g.drawImageWithin (currentThumbnail,
 110                            (getWidth() - w) / 2, y, w, h,
 111                            RectanglePlacement::centred | RectanglePlacement::onlyReduceInSize,
 112                            false);
 113
 114         g.drawFittedText (currentDetails,
 115                           0, y + h + 4, getWidth(), 100,
 116                           Justification::centredTop, numLines);
 117     }
 118 }
 119
 120 //==============================================================================
 121 std::unique_ptr<AccessibilityHandler> ImagePreviewComponent::createAccessibilityHandler()
 122 {
 123     return std::make_unique<AccessibilityHandler> (*this, AccessibilityRole::image);
 124 }
 125
 126 } // namespace juce