--- /dev/null
+/*
+ * Copyright (C) 2010 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.common.api;
+
+/**
+ * Structure returned by onDropEnter/Move and passed to over onDropXyz methods.
+ * <p>
+ * <b>NOTE: This is not a public or final API; if you rely on this be prepared
+ * to adjust your code for the next tools release.</b>
+ * </p>
+ */
+public class DropFeedback {
+ /**
+ * User data that the rule can use in any way it wants to carry state from one
+ * operation to another.
+ * <p/>
+ * Filled and owned by the view rule.
+ */
+ public Object userData;
+
+ /**
+ * If true the next screen update will invoke the paint callback.
+ * <p/>
+ * Filled by the view rule to request a paint, and reset by the canvas after
+ * the paint occurred.
+ */
+ public boolean requestPaint;
+
+ /**
+ * Set to false by the engine when entering a new view target.
+ * The view rule should set this to true if the current view target is not
+ * a valid drop zone.
+ * <p/>
+ * When set to true, the onDropped() method will not be called if the user releases
+ * the mouse button. Depending on the platform or implementation, the mouse cursor
+ * <em>may</em> reflect that the drop operation is invalid.
+ * <p/>
+ * Rationale: an operation like onDropEnter() is called each time the mouse enters
+ * a new view target and is supposed to return null when the drop cannot happen
+ * <em>at all</em> in that target. However a layout like RelativeLayout decorates
+ * potential targets with "hot spots" that are suitable drop zones, whereas some
+ * other parts of the view are not suitable drop zones. In this case the onDropEnter()
+ * or onDropMove() operation would return a {@link DropFeedback} with
+ * <code>invalidTarget=true</code>.
+ */
+ public boolean invalidTarget;
+
+ /**
+ * Painter invoked by the canvas to paint the feedback.
+ * Filled by the view rule, called by the engine.
+ * <p/>
+ */
+ public IFeedbackPainter painter;
+
+ /**
+ * When set to a non-null valid rectangle, this informs the engine that a drag'n'drop
+ * feedback wants to capture the mouse as long as it stays in the given area.
+ * <p/>
+ * When the mouse is captured, drop events will keep going to the rule that started the
+ * capture and the current INode proxy will not change.
+ * <p/>
+ * Filled by the view rule, read by the engine.
+ */
+ public Rect captureArea;
+
+ /**
+ * Set to true by the drag'n'drop engine when the current drag operation is a copy.
+ * When false the operation is a move and <em>after</em> a successful drop the source
+ * elements will be deleted.
+ * <p/>
+ * Filled by the engine, read by view rule.
+ */
+ public boolean isCopy;
+
+ /**
+ * The bounds of the drag, relative to the starting mouse position. For example, if
+ * you have a rectangular view of size 100x80, and you start dragging at position
+ * (15,20) from the top left corner of this rectangle, then the drag bounds would be
+ * (-15,-20, 100x80).
+ * <p>
+ * NOTE: The coordinate units will be in layout/view coordinates. In other words, they
+ * are unaffected by the canvas zoom.
+ */
+ public Rect dragBounds;
+
+ /**
+ * Set to true when the drag'n'drop starts and ends in the same canvas of the
+ * same Eclipse instance.
+ * <p/>
+ * Filled by the engine, read by view rule.
+ */
+ public boolean sameCanvas;
+
+ /**
+ * Density scale for pixels. To compute the dip (device independent pixel) in the
+ * view from a layout coordinate, apply this scale.
+ */
+ public double dipScale = 1.0;
+
+ /**
+ * Initializes the drop feedback with the given user data and paint
+ * callback. A paint is requested if the paint callback is non-null.
+ *
+ * @param userData Data stored for later retrieval by the client
+ * @param painter A callback invoked to paint the drop feedback
+ */
+ public DropFeedback(Object userData, IFeedbackPainter painter) {
+ this.userData = userData;
+ this.painter = painter;
+ this.requestPaint = painter != null;
+ this.captureArea = null;
+ }
+}
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