Moving the state changes during drag-n-drop from startDrag to onDragStart

This will allow drag controller to optinally defer drag, based on some
threshold, by simply deferring the callback onDragStart

Change-Id: I17c06a15e2092b9797c7e57529b12a53d2acae6e

1 files changed, 78 insertions, 0 deletions

diff --git a/src/com/android/launcher3/widget/PendingItemPreviewProvider.java b/src/com/android/launcher3/widget/PendingItemPreviewProvider.java
new file mode 100644
index 000000000..8739390c4
--- /dev/null
+++ b/src/com/android/launcher3/widget/PendingItemPreviewProvider.java
@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2016 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.widget;
+
+import android.graphics.Bitmap;
+import android.graphics.Canvas;
+import android.graphics.Rect;
+import android.view.View;
+
+import com.android.launcher3.HolographicOutlineHelper;
+import com.android.launcher3.Launcher;
+import com.android.launcher3.PendingAddItemInfo;
+import com.android.launcher3.R;
+import com.android.launcher3.Workspace;
+import com.android.launcher3.graphics.DragPreviewProvider;
+
+/**
+ * Extension of {@link DragPreviewProvider} with logic specific to pending widgets/shortcuts
+ * dragged from the widget tray.
+ */
+public class PendingItemPreviewProvider extends DragPreviewProvider {
+
+    private final PendingAddItemInfo mAddInfo;
+    private final Bitmap mPreviewBitmap;
+
+    public PendingItemPreviewProvider(View view, PendingAddItemInfo addInfo, Bitmap preview) {
+        super(view);
+        mAddInfo = addInfo;
+        mPreviewBitmap = preview;
+    }
+
+    @Override
+    public Bitmap createDragOutline(Canvas canvas) {
+        Workspace workspace = Launcher.getLauncher(mView.getContext()).getWorkspace();
+        int[] size = workspace.estimateItemSize(mAddInfo, false);
+
+        int w = size[0];
+        int h = size[1];
+        final Bitmap b = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
+        canvas.setBitmap(b);
+
+        Rect src = new Rect(0, 0, mPreviewBitmap.getWidth(), mPreviewBitmap.getHeight());
+        float scaleFactor = Math.min((w - DRAG_BITMAP_PADDING) / (float) mPreviewBitmap.getWidth(),
+                (h - DRAG_BITMAP_PADDING) / (float) mPreviewBitmap.getHeight());
+        int scaledWidth = (int) (scaleFactor * mPreviewBitmap.getWidth());
+        int scaledHeight = (int) (scaleFactor * mPreviewBitmap.getHeight());
+        Rect dst = new Rect(0, 0, scaledWidth, scaledHeight);
+
+        // center the image
+        dst.offset((w - scaledWidth) / 2, (h - scaledHeight) / 2);
+
+        canvas.drawBitmap(mPreviewBitmap, src, dst, null);
+
+        // Don't clip alpha values for the drag outline if we're using the default widget preview
+        boolean clipAlpha = !(mAddInfo instanceof PendingAddWidgetInfo &&
+                (((PendingAddWidgetInfo) mAddInfo).previewImage == 0));
+        final int outlineColor = mView.getResources().getColor(R.color.outline_color);
+        HolographicOutlineHelper.obtain(mView.getContext())
+                .applyExpensiveOutlineWithBlur(b, canvas, outlineColor, outlineColor, clipAlpha);
+        canvas.setBitmap(null);
+
+        return b;
+    }
+}