Added BaseDropTargetBar, which SearchDropTargetBar extends.

This is to allow for a future AppInfoDropTargetBar.

Change-Id: I5e66129919226eaef1ba1ddb0c0c99d0a6dc48df

1 files changed, 131 insertions, 0 deletions

diff --git a/src/com/android/launcher3/BaseDropTargetBar.java b/src/com/android/launcher3/BaseDropTargetBar.java
new file mode 100644
index 000000000..f478a3530
--- /dev/null
+++ b/src/com/android/launcher3/BaseDropTargetBar.java
@@ -0,0 +1,131 @@
+/*
+ * Copyright (C) 2011 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;
+
+import android.animation.Animator;
+import android.animation.AnimatorListenerAdapter;
+import android.content.Context;
+import android.util.AttributeSet;
+import android.view.View;
+import android.view.animation.AccelerateInterpolator;
+import android.widget.FrameLayout;
+
+import com.android.launcher3.dragndrop.DragController;
+
+/**
+ * Base class for drop target bars (where you can drop apps to do actions such as uninstall).
+ */
+public abstract class BaseDropTargetBar extends FrameLayout implements DragController.DragListener {
+    protected static final int DEFAULT_DRAG_FADE_DURATION = 175;
+
+    protected View mDropTargetBar;
+
+    protected LauncherViewPropertyAnimator mDropTargetBarAnimator;
+    protected static final AccelerateInterpolator sAccelerateInterpolator =
+            new AccelerateInterpolator();
+    protected boolean mAccessibilityEnabled = false;
+
+    protected boolean mDeferOnDragEnd;
+
+    public BaseDropTargetBar(Context context, AttributeSet attrs) {
+        this(context, attrs, 0);
+    }
+
+    public BaseDropTargetBar(Context context, AttributeSet attrs, int defStyle) {
+        super(context, attrs, defStyle);
+    }
+
+    @Override
+    protected void onFinishInflate() {
+        super.onFinishInflate();
+
+        mDropTargetBar = findViewById(R.id.drag_target_bar);
+
+        // Create the various fade animations
+        mDropTargetBar.setAlpha(0f);
+        mDropTargetBarAnimator = new LauncherViewPropertyAnimator(mDropTargetBar);
+        mDropTargetBarAnimator.setInterpolator(sAccelerateInterpolator);
+        mDropTargetBarAnimator.addListener(new AnimatorListenerAdapter() {
+            @Override
+            public void onAnimationStart(Animator animation) {
+                // Ensure that the view is visible for the animation
+                mDropTargetBar.setVisibility(View.VISIBLE);
+            }
+
+            @Override
+            public void onAnimationEnd(Animator animation) {
+                if (mDropTargetBar != null) {
+                    AlphaUpdateListener.updateVisibility(mDropTargetBar, mAccessibilityEnabled);
+                }
+            }
+        });
+    }
+
+
+    /**
+     * Convenience method to animate the alpha of a view using hardware layers.
+     */
+    protected void animateViewAlpha(LauncherViewPropertyAnimator animator, View v, float alpha,
+                                  int duration) {
+        if (v == null) {
+            return;
+        }
+
+        animator.cancel();
+        if (Float.compare(v.getAlpha(), alpha) != 0) {
+            if (duration > 0) {
+                animator.alpha(alpha).withLayer().setDuration(duration).start();
+            } else {
+                v.setAlpha(alpha);
+                AlphaUpdateListener.updateVisibility(v, mAccessibilityEnabled);
+            }
+        }
+    }
+
+    /*
+     * DragController.DragListener implementation
+     */
+    @Override
+    public void onDragStart(DragSource source, ItemInfo info, int dragAction) {
+        showDropTarget();
+    }
+
+    /**
+     * This is called to defer hiding the delete drop target until the drop animation has completed,
+     * instead of hiding immediately when the drag has ended.
+     */
+    protected void deferOnDragEnd() {
+        mDeferOnDragEnd = true;
+    }
+
+    @Override
+    public void onDragEnd() {
+        if (!mDeferOnDragEnd) {
+            hideDropTarget();
+        } else {
+            mDeferOnDragEnd = false;
+        }
+    }
+
+    public abstract void showDropTarget();
+
+    public abstract void hideDropTarget();
+
+    public abstract void enableAccessibleDrag(boolean enable);
+
+    public abstract void setup(Launcher launcher, DragController dragController);
+}