Moving drag-drop related code into a separate package.

This is per an earlier CR comment "we should probably move all this code to its own package (launcher3.dragndrop) in a separate cl".

I'm not moving DragSource because it's referred from gsa code.

Bug: 22609426
Change-Id: Ia7204dab99c0c395c66b77143a2d60411153f5f3

1 files changed, 250 insertions, 0 deletions

diff --git a/src/com/android/launcher3/dragndrop/DragDriver.java b/src/com/android/launcher3/dragndrop/DragDriver.java
new file mode 100644
index 000000000..6e4b430d4
--- /dev/null
+++ b/src/com/android/launcher3/dragndrop/DragDriver.java
@@ -0,0 +1,250 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+ *
+ * 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.launcher3.dragndrop;
+
+import com.android.launcher3.AnotherWindowDropTarget;
+import com.android.launcher3.DropTarget;
+import com.android.launcher3.ItemInfo;
+import com.android.launcher3.Utilities;
+
+import android.content.ClipData;
+import android.content.Intent;
+import android.graphics.Canvas;
+import android.graphics.Point;
+import android.view.DragEvent;
+import android.view.MotionEvent;
+import android.view.View;
+
+/**
+ * Base class for driving a drag/drop operation.
+ */
+public abstract class DragDriver {
+    protected final EventListener mEventListener;
+
+    public interface EventListener {
+        void onDriverDragMove(float x, float y);
+        void onDriverDragExitWindow();
+        void onDriverDragEnd(float x, float y, DropTarget dropTargetOverride);
+        void onDriverDragCancel();
+    }
+
+    public DragDriver(EventListener eventListener) {
+        mEventListener = eventListener;
+    }
+
+    /**
+     * Handles ending of the DragView animation.
+     */
+    public abstract void onDragViewAnimationEnd();
+
+    public boolean onTouchEvent(MotionEvent ev) {
+        final int action = ev.getAction();
+
+        switch (action) {
+            case MotionEvent.ACTION_MOVE:
+                mEventListener.onDriverDragMove(ev.getX(), ev.getY());
+                break;
+            case MotionEvent.ACTION_UP:
+                mEventListener.onDriverDragMove(ev.getX(), ev.getY());
+                mEventListener.onDriverDragEnd(ev.getX(), ev.getY(), null);
+                break;
+            case MotionEvent.ACTION_CANCEL:
+                mEventListener.onDriverDragCancel();
+                break;
+        }
+
+        return true;
+    }
+
+    public abstract boolean onDragEvent (DragEvent event);
+
+
+    public boolean onInterceptTouchEvent(MotionEvent ev) {
+        final int action = ev.getAction();
+
+        switch (action) {
+            case MotionEvent.ACTION_UP:
+                mEventListener.onDriverDragEnd(ev.getX(), ev.getY(), null);
+                break;
+            case MotionEvent.ACTION_CANCEL:
+                mEventListener.onDriverDragCancel();
+                break;
+        }
+
+        return true;
+    }
+
+    public static DragDriver create(
+            DragController dragController, ItemInfo dragInfo, DragView dragView) {
+        if (Utilities.isNycOrAbove()) {
+            return new SystemDragDriver(dragController, dragInfo.getIntent(), dragView);
+        } else {
+            return new InternalDragDriver(dragController);
+        }
+    }
+
+};
+
+/**
+ * Class for driving a system (i.e. framework) drag/drop operation.
+ */
+class SystemDragDriver extends DragDriver {
+    /** Intent associated with the drag operation, or null is there no associated intent.  */
+    private final Intent mDragIntent;
+
+    private final DragView mDragView;
+    boolean mIsFrameworkDragActive = false;
+    boolean mReceivedDropEvent = false;
+    float mLastX = 0;
+    float mLastY = 0;
+
+    public SystemDragDriver(DragController dragController, Intent dragIntent, DragView dragView) {
+        super(dragController);
+        mDragIntent = dragIntent;
+        mDragView = dragView;
+    }
+
+    private static class ShadowBuilder extends View.DragShadowBuilder {
+        final DragView mDragView;
+
+        public ShadowBuilder(DragView dragView) {
+            mDragView = dragView;
+        }
+
+        @Override
+        public void onProvideShadowMetrics (Point size, Point touch) {
+            mDragView.provideDragShadowMetrics(size, touch);
+        }
+
+        @Override
+        public void onDrawShadow(Canvas canvas) {
+            mDragView.drawDragShadow(canvas);
+        }
+    };
+
+    @Override
+    public void onDragViewAnimationEnd() {
+        // Clip data for the drag operation. If there is an intent, create an intent-based ClipData,
+        // which will be passed to a global DND.
+        // If there is no intent, craft a fake ClipData and start a local DND operation; this
+        // ClipData will be ignored.
+        final ClipData dragData = mDragIntent != null ?
+                ClipData.newIntent("", mDragIntent) :
+                ClipData.newPlainText("", "");
+
+        View.DragShadowBuilder shadowBuilder = new ShadowBuilder(mDragView);
+        // TODO: DND flags are in flux, once settled, use the appropriate constant.
+        final int flagGlobal = 1 << 0;
+        final int flagOpaque = 1 << 9;
+        final int flags = (mDragIntent != null ? flagGlobal : 0) | flagOpaque;
+
+        mIsFrameworkDragActive = true;
+
+        if (!mDragView.startDrag(dragData, shadowBuilder, null, flags)) {
+            mIsFrameworkDragActive = false;
+            mEventListener.onDriverDragCancel();
+            return;
+        }
+
+        // Starting from this point, the driver takes over showing the drag shadow, so hiding the
+        // drag view.
+        mDragView.setVisibility(View.INVISIBLE);
+    }
+
+    @Override
+    public boolean onTouchEvent(MotionEvent ev) {
+        return !mIsFrameworkDragActive && super.onTouchEvent(ev);
+    }
+
+    @Override
+    public boolean onInterceptTouchEvent(MotionEvent ev) {
+        return !mIsFrameworkDragActive && super.onInterceptTouchEvent(ev);
+    }
+
+    @Override
+    public boolean onDragEvent (DragEvent event) {
+        if (!mIsFrameworkDragActive) {
+            // We are interested only in drag events started by this driver.
+            return false;
+        }
+
+        final int action = event.getAction();
+
+        switch (action) {
+            case DragEvent.ACTION_DRAG_STARTED:
+                mLastX = event.getX();
+                mLastY = event.getY();
+                return true;
+
+            case DragEvent.ACTION_DRAG_ENTERED:
+                mLastX = event.getX();
+                mLastY = event.getY();
+                return true;
+
+            case DragEvent.ACTION_DRAG_LOCATION:
+                mLastX = event.getX();
+                mLastY = event.getY();
+                mEventListener.onDriverDragMove(event.getX(), event.getY());
+                return true;
+
+            case DragEvent.ACTION_DROP:
+                mLastX = event.getX();
+                mLastY = event.getY();
+                mReceivedDropEvent = true;
+                return true;
+
+            case DragEvent.ACTION_DRAG_EXITED:
+                mLastX = event.getX();
+                mLastY = event.getY();
+                mEventListener.onDriverDragExitWindow();
+                return true;
+
+            case DragEvent.ACTION_DRAG_ENDED:
+                final boolean dragAccepted = event.getResult();
+                final boolean acceptedByAnotherWindow = dragAccepted && !mReceivedDropEvent;
+
+                // When the system drag ends, its drag shadow disappears. Resume showing the drag
+                // view for the possible final animation.
+                mDragView.setVisibility(View.VISIBLE);
+
+                final DropTarget dropTargetOverride = acceptedByAnotherWindow ?
+                        new AnotherWindowDropTarget(mDragView.getContext()) : null;
+
+                mEventListener.onDriverDragEnd(mLastX, mLastY, dropTargetOverride);
+                mIsFrameworkDragActive = false;
+                return true;
+
+            default:
+                return false;
+        }
+    }
+};
+
+/**
+ * Class for driving an internal (i.e. not using framework) drag/drop operation.
+ */
+class InternalDragDriver extends DragDriver {
+    public InternalDragDriver(DragController dragController) {
+        super(dragController);
+    }
+
+    @Override
+    public void onDragViewAnimationEnd() {}
+
+    @Override
+    public boolean onDragEvent (DragEvent event) { return false; }
+};