1 files changed, 141 insertions, 0 deletions
diff --git a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/editors/layout/gle2/SelectionHandle.java b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/editors/layout/gle2/SelectionHandle.java
new file mode 100644
index 000000000..c2db2431c
--- /dev/null
+++ b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/editors/layout/gle2/SelectionHandle.java
@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Eclipse Public License, Version 1.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.eclipse.org/org/documents/epl-v10.php
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.ide.eclipse.adt.internal.editors.layout.gle2;
+
+import org.eclipse.swt.SWT;
+
+/**
+ * A selection handle is a small rectangle on the border of a selected view which lets you
+ * change the size of the view by dragging it.
+ */
+public class SelectionHandle {
+    /**
+     * Size of the selection handle radius, in control coordinates. Note that this isn't
+     * necessarily a <b>circular</b> radius; in the case of a rectangular handle, the
+     * width and the height are both equal to this radius.
+     * Note also that this radius is in <b>control</b> coordinates, whereas the rest
+     * of the class operates in layout coordinates. This is because we do not want the
+     * selection handles to grow or shrink along with the screen zoom; they are always
+     * at the given pixel size in the control.
+     */
+    public final static int PIXEL_RADIUS = 3;
+
+    /**
+     * Extra number of pixels to look beyond the actual radius of the selection handle
+     * when matching mouse positions to handles
+     */
+    public final static int PIXEL_MARGIN = 2;
+
+    /** The position of the handle in the selection rectangle */
+    enum Position {
+        TOP_MIDDLE(SWT.CURSOR_SIZEN),
+        TOP_RIGHT(SWT.CURSOR_SIZENE),
+        RIGHT_MIDDLE(SWT.CURSOR_SIZEE),
+        BOTTOM_RIGHT(SWT.CURSOR_SIZESE),
+        BOTTOM_MIDDLE(SWT.CURSOR_SIZES),
+        BOTTOM_LEFT(SWT.CURSOR_SIZESW),
+        LEFT_MIDDLE(SWT.CURSOR_SIZEW),
+        TOP_LEFT(SWT.CURSOR_SIZENW);
+
+        /** Corresponding SWT cursor value */
+        private int mSwtCursor;
+
+        private Position(int swtCursor) {
+            mSwtCursor = swtCursor;
+        }
+
+        private int getCursorType() {
+            return mSwtCursor;
+        }
+
+        /** Is the {@link SelectionHandle} somewhere on the left edge? */
+        boolean isLeft() {
+            return this == TOP_LEFT || this == LEFT_MIDDLE || this == BOTTOM_LEFT;
+        }
+
+        /** Is the {@link SelectionHandle} somewhere on the right edge? */
+        boolean isRight() {
+            return this == TOP_RIGHT || this == RIGHT_MIDDLE || this == BOTTOM_RIGHT;
+        }
+
+        /** Is the {@link SelectionHandle} somewhere on the top edge? */
+        boolean isTop() {
+            return this == TOP_LEFT || this == TOP_MIDDLE || this == TOP_RIGHT;
+        }
+
+        /** Is the {@link SelectionHandle} somewhere on the bottom edge? */
+        boolean isBottom() {
+            return this == BOTTOM_LEFT || this == BOTTOM_MIDDLE || this == BOTTOM_RIGHT;
+        }
+    };
+
+    /** The x coordinate of the center of the selection handle */
+    public final int centerX;
+    /** The y coordinate of the center of the selection handle */
+    public final int centerY;
+    /** The position of the handle in the selection rectangle */
+    private final Position mPosition;
+
+    /**
+     * Constructs a new {@link SelectionHandle} at the given layout coordinate
+     * corresponding to a handle at the given {@link Position}.
+     *
+     * @param centerX the x coordinate of the center of the selection handle
+     * @param centerY y coordinate of the center of the selection handle
+     * @param position the position of the handle in the selection rectangle
+     */
+    public SelectionHandle(int centerX, int centerY, Position position) {
+        mPosition = position;
+        this.centerX = centerX;
+        this.centerY = centerY;
+    }
+
+    /**
+     * Determines whether the given {@link LayoutPoint} is within the given distance in
+     * layout coordinates. The distance should incorporate at least the equivalent
+     * distance to the control coordinate space {@link #PIXEL_RADIUS}, but usually with a
+     * few extra pixels added in to make the corners easier to target.
+     *
+     * @param point the mouse position in layout coordinates
+     * @param distance the distance from the center of the handle to check whether the
+     *            point fits within
+     * @return true if the given point is within the given distance of this handle
+     */
+    public boolean contains(LayoutPoint point, int distance) {
+        return (point.x >= centerX - distance
+              && point.x <= centerX + distance
+              && point.y >= centerY - distance
+              && point.y <= centerY + distance);
+    }
+
+    /**
+     * Returns the position of the handle in the selection rectangle
+     *
+     * @return the position of the handle in the selection rectangle
+     */
+    public Position getPosition() {
+        return mPosition;
+    }
+
+    /**
+     * Returns the SWT cursor type to use for this selection handle
+     *
+     * @return the position of the handle in the selection rectangle
+     */
+    public int getSwtCursorType() {
+        return mPosition.getCursorType();
+    }
+}