Create handles for ImageDataProvider and ImageFilenameProvider on demand

Author: ShahzaibIbrahim

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/graphics/Image.java

@@ -556,7 +556,6 @@ public Image(Device device, ImageFileNameProvider imageFileNameProvider) {
 	super(device);
 	this.imageProvider = new ImageFileNameProviderWrapper(imageFileNameProvider);
 	initialNativeZoom = DPIUtil.getNativeDeviceZoom();
-	imageProvider.getImageMetadata(getZoom());
 	init();
 	this.device.registerResourceWithZoomSupport(this);
 }
@@ -594,7 +593,6 @@ public Image(Device device, ImageDataProvider imageDataProvider) {
 	super(device);
 	this.imageProvider = new ImageDataProviderWrapper(imageDataProvider);
 	initialNativeZoom = DPIUtil.getNativeDeviceZoom();
-	imageProvider.getImageMetadata(getZoom());
 	init();
 	this.device.registerResourceWithZoomSupport(this);
 }
@@ -2081,6 +2079,13 @@ public static Image win32_new(Device device, int type, long handle, int nativeZo
 	return image;
 }
 
+private void destroyHandle(int zoom) {
+	ImageHandle imageHandle = zoomLevelToImageHandle.remove(zoom);
+	if (imageHandle != null) {
+	     destroyHandle(imageHandle.handle);
+	}
+}
+
 private abstract class AbstractImageProviderWrapper {
 	abstract Object getProvider();
 	protected abstract Rectangle getBounds(int zoom);
@@ -2115,17 +2120,24 @@ private class ImageFileNameProviderWrapper extends AbstractImageProviderWrapper
 	 * ImageFileNameProvider to provide file names at various Zoom levels
 	 */
 	private final ImageFileNameProvider provider;
+	private boolean isDestroyed;
+	private int width;
+	private int height;
+	private final static int BASE_ZOOM = 100;
 
 	ImageFileNameProviderWrapper(ImageFileNameProvider provider) {
 		checkProvider(provider, ImageFileNameProvider.class);
 		this.provider = provider;
+		ImageHandle handleAt100 = getImageMetadata(BASE_ZOOM);
+		width = handleAt100.width;
+		height = handleAt100.height;
+		destroyHandle(BASE_ZOOM);
 	}
 
 	@Override
 	protected Rectangle getBounds(int zoom) {
-		ImageHandle imageHandle = zoomLevelToImageHandle.values().iterator().next();
-		Rectangle rectangle = new Rectangle(0, 0, imageHandle.width, imageHandle.height);
-		return DPIUtil.scaleBounds(rectangle, zoom, imageHandle.zoom);
+		Rectangle rectangle = new Rectangle(0, 0, width, height);
+		return DPIUtil.scaleBounds(rectangle, zoom, BASE_ZOOM);
 	}
 
 	@Override
@@ -2154,11 +2166,6 @@ ImageHandle getImageMetadata(int zoom) {
 		return zoomLevelToImageHandle.get(zoom);
 	}
 
-	@Override
-	boolean isDisposed() {
-		return zoomLevelToImageHandle.isEmpty();
-	}
-
 	@Override
 	Object getProvider() {
 		return provider;
@@ -2173,6 +2180,16 @@ public int hashCode() {
 	ImageFileNameProviderWrapper createCopy(Image image) {
 		return image.new ImageFileNameProviderWrapper(provider);
 	}
+
+	@Override
+	boolean isDisposed() {
+		return this.isDestroyed;
+	}
+
+	@Override
+	protected void destroy() {
+		this.isDestroyed = true;
+	}
 }
 
 private class ImageDataProviderWrapper extends AbstractImageProviderWrapper {
@@ -2181,17 +2198,24 @@ private class ImageDataProviderWrapper extends AbstractImageProviderWrapper {
 	 * ImageDataProvider to provide ImageData at various Zoom levels
 	 */
 	private final ImageDataProvider provider;
+	private int width;
+	private int height;
+	private boolean isDestroyed;
+	private final static int BASE_ZOOM = 100;
 
 	ImageDataProviderWrapper(ImageDataProvider provider) {
 		checkProvider(provider, ImageDataProvider.class);
 		this.provider = provider;
+		ImageHandle handleAt100 = getImageMetadata(BASE_ZOOM);
+		width = handleAt100.width;
+		height = handleAt100.height;
+		destroyHandle(BASE_ZOOM);
 	}
 
 	@Override
 	protected Rectangle getBounds(int zoom) {
-		ImageHandle imageHandle = zoomLevelToImageHandle.values().iterator().next();
-		Rectangle rectangle = new Rectangle(0, 0, imageHandle.width, imageHandle.height);
-		return DPIUtil.scaleBounds(rectangle, zoom, imageHandle.zoom);
+		Rectangle rectangle = new Rectangle(0, 0, width, height);
+		return DPIUtil.scaleBounds(rectangle, zoom, BASE_ZOOM);
 	}
 
 	@Override
@@ -2211,7 +2235,12 @@ ImageHandle getImageMetadata(int zoom) {
 
 	@Override
 	boolean isDisposed() {
-		return zoomLevelToImageHandle.isEmpty();
+		return this.isDestroyed;
+	}
+
+	@Override
+	protected void destroy() {
+		this.isDestroyed = true;
 	}
 
 	@Override