Implement the new Photo picker, part two.

chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerBitmapView.java

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.photo_picker;
+
+import android.content.Context;
+import android.content.res.Resources;
+import android.graphics.Bitmap;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.PorterDuff;
+import android.graphics.drawable.Drawable;
+import android.support.annotation.Nullable;
+import android.support.graphics.drawable.VectorDrawableCompat;
+import android.util.AttributeSet;
+import android.view.View;
+import android.widget.ImageView;
+import android.widget.TextView;
+
+import org.chromium.base.ApiCompatibilityUtils;
+import org.chromium.chrome.R;
+import org.chromium.chrome.browser.widget.selection.SelectableItemView;
+import org.chromium.chrome.browser.widget.selection.SelectionDelegate;
+
+import java.util.List;
+
+/**
+ * A container class for a view showing a photo in the Photo Picker.
+ */
+public class PickerBitmapView extends SelectableItemView<PickerBitmap> {
+    // Our context.
+    private Context mContext;
+
+    // Our parent category.
+    private PickerCategoryView mCategoryView;
+
+    // Our selection delegate.
+    private SelectionDelegate<PickerBitmap> mSelectionDelegate;
+
+    // The request details (meta-data) for the bitmap shown.
+    private PickerBitmap mBitmapDetails;
+
+    // The image view containing the bitmap.
+    private ImageView mIconView;
+
+    // The view behind the image, representing the selection border.
+    private View mBorderView;
+
+    // The camera/gallery special tile (with icon as drawable).
+    private TextView mSpecialTile;
+
+    // Whether the image has been loaded already.
+    private boolean mImageLoaded;
+
+    /**
+     * Constructor for inflating from XML.
+     */
+    public PickerBitmapView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        mContext = context;
+    }
+
+    @Override
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+
+        if (mCategoryView == null) return;
+
+        int width = mCategoryView.getImageSize();
+        int height = mCategoryView.getImageSize();
+        setMeasuredDimension(width, height);
+    }
+
+    @Override
+    protected void onFinishInflate() {
+        super.onFinishInflate();
+        mIconView = (ImageView) findViewById(R.id.bitmap_view);
+        mBorderView = findViewById(R.id.border);
+        mSpecialTile = (TextView) findViewById(R.id.special_tile);
+    }
+
+    @Override
+    public void onClick() {
+        // TODO(finnur): Remove the null checks here and below.
+        if (isGalleryTile()) {
+            mCategoryView.showGallery();
+            return;
+        } else if (isCameraTile()) {
+            mCategoryView.showCamera();
+            return;
+        }
+
+        // The SelectableItemView expects long press to be the selection event, but this class wants
+        // that to happen on click instead.
+        super.onLongClick(this);
+    }
+
+    @Override
+    protected boolean toggleSelectionForItem(PickerBitmap item) {
+        if (isGalleryTile() || isCameraTile()) return false;
+        return super.toggleSelectionForItem(item);
+    }
+
+    @Override
+    public void setChecked(boolean checked) {
+        if (!isPictureTile()) {
+            return;
+        }
+
+        super.setChecked(checked);
+        updateSelectionState();
+    }
+
+    @Override
+    public void onSelectionStateChange(List<PickerBitmap> selectedItems) {
+        updateSelectionState();
+    }
+
+    /**
+     * Sets the {@link PickerCategoryView} for this PickerBitmapView.
+     * @param categoryView The category view showing the images. Used to access
+     *     common functionality and sizes and retrieve the {@link SelectionDelegate}.
+     */
+    public void setCategoryView(PickerCategoryView categoryView) {
+        mCategoryView = categoryView;
+        mSelectionDelegate = mCategoryView.getSelectionDelegate();
+        super.setSelectionDelegate(mSelectionDelegate);
+    }
+
+    /**
+     * Completes the initialization of the PickerBitmapView. Must be called before the image can
+     * respond to click events.
+     * @param request The request represented by this PickerBitmapView.
+     * @param thumbnail The Bitmap to use for the thumbnail (or null).
+     * @param placeholder Whether the image given is a placeholder or the actual image.
+     */
+    public void initialize(PickerBitmap request, @Nullable Bitmap thumbnail, boolean placeholder) {
+        resetTile();
+
+        mBitmapDetails = request;

[Theresa, 2017/04/04 18:40:46]

nit: should the @param be renamed to match mBitmapDetails?

[Finnur, 2017/04/05 15:14:39]

Done.

+        setItem(request);
+        setThumbnailBitmap(thumbnail);
+        mImageLoaded = !placeholder;
+
+        updateSelectionState();
+    }
+
+    /**
+     * Initialization for the special tiles (camera/gallery icon).
+     * @param request The request represented by this PickerBitmapView.
+     */
+    public void initializeSpecialTile(PickerBitmap request) {
+        Bitmap icon;
+        int labelStringId;
+        Resources resources = mContext.getResources();
+
+        if (isCameraTile()) {
+            int iconBitmapId = R.drawable.ic_photo_camera;
+            Drawable image = ApiCompatibilityUtils.getDrawable(resources, iconBitmapId);
+            ApiCompatibilityUtils.setCompoundDrawablesRelativeWithIntrinsicBounds(
+                    mSpecialTile, null, image, null, null);
+            labelStringId = R.string.file_picker_camera;
+        } else {
+            Drawable collections = VectorDrawableCompat.create(
+                    resources, R.drawable.ic_collections_grey, mContext.getTheme());
+            icon = Bitmap.createBitmap(collections.getIntrinsicWidth(),
+                    collections.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
+            Canvas canvas = new Canvas(icon);
+            collections.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
+            collections.draw(canvas);

[Theresa, 2017/04/04 18:40:46]

Can collections be passed directly to
ApiCompatibilityUTils#setCompoundDrawables...? We set VectorDrawable's as
compound drawables for the empty text view in SelectableListLayout without
issue.

I'm picturing something like this:
public void initializeSpecialTile(PickerBitmap request) {
    int labelStringId;
    Drawable image;
    Resources resources = mContext.getResources();

    if (isCameraTile()) {
        image = ApiCompatibilityUtils.getDrawable(resources,
R.drawable.ic_photo_camera);
        labelStringId = R.string.file_picker_camera;
    } else {
        image = VectorDrawableCompat.create(
                resources, R.drawable.ic_collections_grey, mContext.getTheme());
        labelStringId = R.string.file_picker_browse;
    }

    ApiCompatibilityUtils.setCompoundDrawablesRelativeWithIntrinsicBounds(
            mSpecialTile, null, image, null, null);
    mSpecialTile.setText(labelStringId);

    initialize(request, null, false);

    // Reset visibility, since #initialize() sets mSpecialTile visibility to
GONE.
    mSpecialTile.setVisibility(View.VISIBLE);
}


With some constructs in setThumbnailBitmap() to deal with @Nullable Bitmap
thumbnail.

[Finnur, 2017/04/05 15:14:39]

Done. Except the last part (constructs for null bitmaps). Is it necessary to
deal with a null bitmap specifically?

[Theresa, 2017/04/05 15:48:23]

If Android is happy with a null passed in to #setImageBitmap() then there's no
need add special handling.

+            ApiCompatibilityUtils.setCompoundDrawablesRelativeWithIntrinsicBounds(
+                    mSpecialTile, null, collections, null, null);
+            labelStringId = R.string.file_picker_browse;
+        }
+
+        mSpecialTile.setText(labelStringId);
+
+        int size = mCategoryView.getImageSize();
+        Bitmap tile = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888);
+        tile.eraseColor(Color.argb(0, 0, 0, 0));
+        initialize(request, tile, false);
+
+        mSpecialTile.setVisibility(View.VISIBLE);
+    }
+
+    /**
+     * Sets a thumbnail bitmap for the current view.
+     * @param thumbnail The Bitmap to use for the icon ImageView.
+     * @return True if no image was loaded before (e.g. not even a low-res image).
+     */
+    public boolean setThumbnailBitmap(Bitmap thumbnail) {
+        mIconView.setImageBitmap(thumbnail);
+
+        boolean noImageWasLoaded = !mImageLoaded;
+        mImageLoaded = true;
+        updateSelectionState();
+
+        return noImageWasLoaded;
+    }
+
+    /**
+     * Resets the view to its starting state, which is necessary when the view is about to be
+     * re-used.
+     */
+    private void resetTile() {
+        mSpecialTile.setVisibility(View.GONE);
+    }
+
+    /**
+     * Updates the selection controls for this view.
+     */
+    private void updateSelectionState() {
+        boolean special = !isPictureTile();
+        boolean checked = super.isChecked();
+        boolean anySelection =
+                mSelectionDelegate != null && mSelectionDelegate.isSelectionEnabled();
+        int bgColorId, fgColorId;
+        if (!special) {
+            bgColorId = R.color.file_picker_tile_bg_color;
+            fgColorId = R.color.file_picker_special_tile_color;
+        } else if (!anySelection) {
+            bgColorId = R.color.file_picker_special_tile_bg_color;
+            fgColorId = R.color.file_picker_special_tile_color;
+        } else {
+            bgColorId = R.color.file_picker_special_tile_disabled_bg_color;
+            fgColorId = R.color.file_picker_special_tile_disabled_color;
+        }
+
+        Resources resources = mContext.getResources();
+        mBorderView.setBackgroundColor(ApiCompatibilityUtils.getColor(resources, bgColorId));
+        mSpecialTile.setTextColor(ApiCompatibilityUtils.getColor(resources, fgColorId));
+        Drawable[] drawables = mSpecialTile.getCompoundDrawables();
+        // The textview only has a top compound drawable (2nd element).
+        if (drawables[1] != null) {
+            int color = ApiCompatibilityUtils.getColor(resources, fgColorId);
+            drawables[1].setColorFilter(color, PorterDuff.Mode.SRC_IN);
+        }
+    }
+
+    private boolean isGalleryTile() {
+        return mBitmapDetails != null && mBitmapDetails.type() == PickerBitmap.TileTypes.GALLERY;
+    }
+
+    private boolean isCameraTile() {
+        return mBitmapDetails != null && mBitmapDetails.type() == PickerBitmap.TileTypes.CAMERA;
+    }
+
+    private boolean isPictureTile() {
+        return mBitmapDetails != null && mBitmapDetails.type() == PickerBitmap.TileTypes.PICTURE;
+    }
+}