webkitgtk-2.16.5HEADwebkitgtk-2.16.5master

1 files changed, 157 insertions, 0 deletions

diff --git a/Source/WebInspectorUI/UserInterface/Models/BackForwardEntry.js b/Source/WebInspectorUI/UserInterface/Models/BackForwardEntry.js
new file mode 100644
index 000000000..2c5ec3dab
--- /dev/null
+++ b/Source/WebInspectorUI/UserInterface/Models/BackForwardEntry.js
@@ -0,0 +1,157 @@
+/*
+ *  Copyright (C) 2013 University of Washington. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+WebInspector.BackForwardEntry = class BackForwardEntry extends WebInspector.Object
+{
+    constructor(contentView, cookie)
+    {
+        super();
+
+        this._contentView = contentView;
+
+        // ContentViews may be shared across multiple ContentViewContainers.
+        // A BackForwardEntry containing a tombstone doesn't actually have
+        // the real ContentView, and so should not close it.
+        this._tombstone = false;
+
+        // Cookies are compared with Object.shallowEqual, so should not store objects or arrays.
+        this._cookie = cookie || {};
+        this._scrollPositions = [];
+
+        contentView.saveToCookie(this._cookie);
+    }
+
+    // Public
+
+    makeCopy(newCookie)
+    {
+        let copy = new WebInspector.BackForwardEntry(this._contentView, newCookie || this.cookie);
+        copy._tombstone = this._tombstone;
+        copy._scrollPositions = this._scrollPositions.slice();
+        return copy;
+    }
+
+    get contentView()
+    {
+        return this._contentView;
+    }
+
+    get cookie()
+    {
+        // Cookies are immutable; they represent a specific navigation action.
+        return Object.shallowCopy(this._cookie);
+    }
+
+    get tombstone()
+    {
+        return this._tombstone;
+    }
+
+    set tombstone(tombstone)
+    {
+        this._tombstone = tombstone;
+    }
+
+    prepareToShow(shouldCallShown)
+    {
+        console.assert(!this._tombstone, "Should not be calling shown on a tombstone");
+
+        this._restoreFromCookie();
+
+        this.contentView.visible = true;
+        if (shouldCallShown)
+            this.contentView.shown();
+        this.contentView.needsLayout();
+    }
+
+    prepareToHide()
+    {
+        console.assert(!this._tombstone, "Should not be calling hidden on a tombstone");
+
+        this.contentView.visible = false;
+        this.contentView.hidden();
+
+        this._saveScrollPositions();
+    }
+
+    isEqual(other)
+    {
+        if (!other)
+            return false;
+        return this._contentView === other._contentView && Object.shallowEqual(this._cookie, other._cookie);
+    }
+
+    // Private
+
+    _restoreFromCookie()
+    {
+        this._restoreScrollPositions();
+        this.contentView.restoreFromCookie(this.cookie);
+    }
+
+    _restoreScrollPositions()
+    {
+        // If no scroll positions are saved, do nothing.
+        if (!this._scrollPositions.length)
+            return;
+
+        var scrollableElements = this.contentView.scrollableElements || [];
+        console.assert(this._scrollPositions.length === scrollableElements.length);
+
+        for (var i = 0; i < scrollableElements.length; ++i) {
+            var position = this._scrollPositions[i];
+            var element = scrollableElements[i];
+            if (!element)
+                continue;
+
+            // Restore the top scroll position by either scrolling to the bottom or to the saved position.
+            element.scrollTop = position.isScrolledToBottom ? element.scrollHeight : position.scrollTop;
+
+            // Don't restore the left scroll position when scrolled to the bottom. This way the when content changes
+            // the user won't be left in a weird horizontal position.
+            element.scrollLeft = position.isScrolledToBottom ? 0 : position.scrollLeft;
+        }
+    }
+
+    _saveScrollPositions()
+    {
+        var scrollableElements = this.contentView.scrollableElements || [];
+        var scrollPositions = [];
+        for (var i = 0; i < scrollableElements.length; ++i) {
+            var element = scrollableElements[i];
+            if (!element)
+                continue;
+
+            let position = {scrollTop: element.scrollTop, scrollLeft: element.scrollLeft};
+            if (this.contentView.shouldKeepElementsScrolledToBottom)
+                position.isScrolledToBottom = element.isScrolledToBottom();
+
+            scrollPositions.push(position);
+        }
+
+        this._scrollPositions = scrollPositions;
+    }
+};