1 files changed, 86 insertions, 0 deletions
diff --git a/mobile/android/base/java/org/mozilla/gecko/widget/ThumbnailView.java b/mobile/android/base/java/org/mozilla/gecko/widget/ThumbnailView.java
new file mode 100644
index 000000000..5ab00ea7f
--- /dev/null
+++ b/mobile/android/base/java/org/mozilla/gecko/widget/ThumbnailView.java
@@ -0,0 +1,86 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.widget;
+
+import org.mozilla.gecko.R;
+
+import android.content.Context;
+import android.graphics.Canvas;
+import android.graphics.Matrix;
+import android.graphics.drawable.Drawable;
+import android.util.AttributeSet;
+import android.support.v4.content.ContextCompat;
+import org.mozilla.gecko.widget.themed.ThemedImageView;
+
+/* Special version of ImageView for thumbnails. Scales a thumbnail so that it maintains its aspect
+ * ratio and so that the images width and height are the same size or greater than the view size
+ */
+public class ThumbnailView extends ThemedImageView {
+    private static final String LOGTAG = "GeckoThumbnailView";
+
+    final private Matrix mMatrix;
+    private int mWidthSpec = -1;
+    private int mHeightSpec = -1;
+    private boolean mLayoutChanged;
+    private boolean mScale = false;
+
+    public ThumbnailView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        mMatrix = new Matrix();
+        mLayoutChanged = true;
+    }
+
+    @Override
+    public void onDraw(Canvas canvas) {
+        if (!mScale) {
+            super.onDraw(canvas);
+            return;
+        }
+
+        Drawable d = getDrawable();
+        if (mLayoutChanged) {
+            int w1 = d.getIntrinsicWidth();
+            int h1 = d.getIntrinsicHeight();
+            int w2 = getWidth();
+            int h2 = getHeight();
+
+            float scale = ((w2 / h2) < (w1 / h1)) ? (float) h2 / h1 : (float) w2 / w1;
+            mMatrix.setScale(scale, scale);
+        }
+
+        int saveCount = canvas.save();
+        canvas.concat(mMatrix);
+        d.draw(canvas);
+        canvas.restoreToCount(saveCount);
+    }
+
+    @Override
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        // OnLayout.changed isn't a reliable measure of whether or not the size of this view has changed
+        // neither is onSizeChanged called often enough. Instead, we track changes in size ourselves, and
+        // only invalidate this matrix if we have a new width/height spec
+        if (widthMeasureSpec != mWidthSpec || heightMeasureSpec != mHeightSpec) {
+            mWidthSpec = widthMeasureSpec;
+            mHeightSpec = heightMeasureSpec;
+            mLayoutChanged = true;
+        }
+        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+    }
+
+    @Override
+    public void setImageDrawable(Drawable drawable) {
+        if (drawable == null) {
+            drawable = ContextCompat.getDrawable(getContext(), R.drawable.tab_panel_tab_background);
+            setScaleType(ScaleType.FIT_XY);
+            mScale = false;
+        } else {
+            mScale = true;
+            setScaleType(ScaleType.FIT_CENTER);
+        }
+
+        super.setImageDrawable(drawable);
+    }
+}