v7/appcompat/src/android/support/v7/internal/widget/TintRatingBar.java

/*
 * Copyright (C) 2014 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 android.support.v7.internal.widget;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Shader;
import android.graphics.drawable.AnimationDrawable;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.ClipDrawable;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.LayerDrawable;
import android.graphics.drawable.ShapeDrawable;
import android.graphics.drawable.shapes.RoundRectShape;
import android.graphics.drawable.shapes.Shape;
import android.support.v4.graphics.drawable.DrawableWrapper;
import android.support.v4.view.ViewCompat;
import android.util.AttributeSet;
import android.view.Gravity;
import android.widget.RatingBar;

/**
 * An tint aware {@link android.widget.RatingBar}.
 * <p>
 * This will automatically be used when you use {@link android.widget.RatingBar} in your
 * layouts. You should only need to manually use this class when writing custom views.
 */
public class TintRatingBar extends RatingBar {

    private static final int[] TINT_ATTRS = {
            android.R.attr.indeterminateDrawable,
            android.R.attr.progressDrawable
    };

    private Bitmap mSampleTile;

    public TintRatingBar(Context context) {
        this(context, null);
    }

    public TintRatingBar(Context context, AttributeSet attrs) {
        this(context, attrs, android.R.attr.ratingBarStyle);
    }

    public TintRatingBar(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);

        if (TintManager.SHOULD_BE_USED) {
            TintTypedArray a = TintTypedArray.obtainStyledAttributes(getContext(), attrs,
                    TINT_ATTRS, defStyleAttr, 0);

            Drawable drawable = a.getDrawable(0);
            if (drawable != null) {
                setIndeterminateDrawable(tileifyIndeterminate(drawable));
            }

            drawable = a.getDrawable(1);
            if (drawable != null) {
                setProgressDrawable(tileify(drawable, false));
            }

            a.recycle();
        }
    }

    /**
     * Converts a drawable to a tiled version of itself. It will recursively
     * traverse layer and state list drawables.
     */
    private Drawable tileify(Drawable drawable, boolean clip) {
        if (drawable instanceof DrawableWrapper) {
            Drawable inner = ((DrawableWrapper) drawable).getWrappedDrawable();
            if (inner != null) {
                inner = tileify(inner, clip);
                ((DrawableWrapper) drawable).setWrappedDrawable(inner);
            }
        } else if (drawable instanceof LayerDrawable) {
            LayerDrawable background = (LayerDrawable) drawable;
            final int N = background.getNumberOfLayers();
            Drawable[] outDrawables = new Drawable[N];

            for (int i = 0; i < N; i++) {
                int id = background.getId(i);
                outDrawables[i] = tileify(background.getDrawable(i),
                        (id == android.R.id.progress || id == android.R.id.secondaryProgress));
            }
            LayerDrawable newBg = new LayerDrawable(outDrawables);

            for (int i = 0; i < N; i++) {
                newBg.setId(i, background.getId(i));
            }

            return newBg;

        } else if (drawable instanceof BitmapDrawable) {
            final Bitmap tileBitmap = ((BitmapDrawable) drawable).getBitmap();
            if (mSampleTile == null) {
                mSampleTile = tileBitmap;
            }

            final ShapeDrawable shapeDrawable = new ShapeDrawable(getDrawableShape());
            final BitmapShader bitmapShader = new BitmapShader(tileBitmap,
                    Shader.TileMode.REPEAT, Shader.TileMode.CLAMP);
            shapeDrawable.getPaint().setShader(bitmapShader);
            return (clip) ? new ClipDrawable(shapeDrawable, Gravity.LEFT,
                    ClipDrawable.HORIZONTAL) : shapeDrawable;
        }

        return drawable;
    }

    /**
     * Convert a AnimationDrawable for use as a barberpole animation.
     * Each frame of the animation is wrapped in a ClipDrawable and
     * given a tiling BitmapShader.
     */
    private Drawable tileifyIndeterminate(Drawable drawable) {
        if (drawable instanceof AnimationDrawable) {
            AnimationDrawable background = (AnimationDrawable) drawable;
            final int N = background.getNumberOfFrames();
            AnimationDrawable newBg = new AnimationDrawable();
            newBg.setOneShot(background.isOneShot());

            for (int i = 0; i < N; i++) {
                Drawable frame = tileify(background.getFrame(i), true);
                frame.setLevel(10000);
                newBg.addFrame(frame, background.getDuration(i));
            }
            newBg.setLevel(10000);
            drawable = newBg;
        }
        return drawable;
    }

    private Shape getDrawableShape() {
        final float[] roundedCorners = new float[] { 5, 5, 5, 5, 5, 5, 5, 5 };
        return new RoundRectShape(roundedCorners, null, null);
    }

    @Override
    protected synchronized void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        if (mSampleTile != null) {
            final int width = mSampleTile.getWidth() * getNumStars();
            setMeasuredDimension(ViewCompat.resolveSizeAndState(width, widthMeasureSpec, 0),
                    getMeasuredHeight());
        }
    }

}