fix image scaling on reload with border, margin, or padding > 0

On reload images have their buffer set already from cache when
Image::sizeAllocateImpl() is called.
In that case the widget is still at size 1x1. In that case
 getContentHeight() and getContentWidth() return values <= 0
when border + margin + padding > 0.

To fix the issue use the new size given in allocation instead of the
current widget dimensions to determine whether to scale the buffer.

(report and initial analysis by furaisanjin <furaisanjin@gmail.com>)

1 files changed, 3 insertions, 1 deletions

diff --git a/dw/image.cc b/dw/image.cc
index 0a690999..a76d999b 100644
--- a/dw/image.cc
+++ b/dw/image.cc
@@ -209,7 +209,9 @@ void Image::sizeAllocateImpl (core::Allocation *allocation)
        " = %d - %d = %d\n", this->getHeight(), getStyle()->boxDiffHeight(),
        this->getHeight() - getStyle()->boxDiffHeight());
 #endif
-   if (buffer && (getContentWidth () > 0 || getContentHeight () > 0)) {
+   if (buffer &&
+       (allocation->width - dx > 0 ||
+        allocation->ascent + allocation->descent - dy > 0)) {
       // Zero content size : simply wait...
       // Only one dimension: naturally scale
       oldBuffer = buffer;