com.stepstone.stepper.internal.DottedProgressBar.java Source code

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Here is the source code for com.stepstone.stepper.internal.DottedProgressBar.java

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/*
Copyright 2016 StepStone Services
    
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.stepstone.stepper.internal;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.drawable.Drawable;
import android.support.annotation.ColorInt;
import android.support.v4.content.ContextCompat;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.view.animation.AccelerateDecelerateInterpolator;
import android.widget.LinearLayout;

import com.stepstone.stepper.R;
import com.stepstone.stepper.util.TintUtil;

/**
 * An indicator displaying the current position in a list of items with dots.
 */
public class DottedProgressBar extends LinearLayout {

    private static final float FULL_SCALE = 1f;
    private static final float HALF_SCALE = 0.5f;
    private static final int DURATION_IMMEDIATE = 0;
    private static final int SCALE_ANIMATION_DEFAULT_DURATION = 300;

    @ColorInt
    private int mUnselectedColor;

    @ColorInt
    private int mSelectedColor;

    private int mDotCount;

    private int mCurrent;

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

    public DottedProgressBar(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public DottedProgressBar(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        mSelectedColor = ContextCompat.getColor(context, R.color.ms_selectedColor);
        mUnselectedColor = ContextCompat.getColor(context, R.color.ms_unselectedColor);
        if (attrs != null) {
            final TypedArray a = getContext().obtainStyledAttributes(attrs, R.styleable.DottedProgressBar,
                    defStyleAttr, 0);

            if (a.hasValue(R.styleable.DottedProgressBar_ms_activeDotColor)) {
                mSelectedColor = a.getColor(R.styleable.DottedProgressBar_ms_activeDotColor, mSelectedColor);
            }
            if (a.hasValue(R.styleable.DottedProgressBar_ms_inactiveDotColor)) {
                mUnselectedColor = a.getColor(R.styleable.DottedProgressBar_ms_inactiveDotColor, mUnselectedColor);
            }

            a.recycle();
        }
    }

    public void setUnselectedColor(@ColorInt int unselectedColor) {
        this.mUnselectedColor = unselectedColor;
    }

    public void setSelectedColor(@ColorInt int selectedColor) {
        this.mSelectedColor = selectedColor;
    }

    public void setDotCount(int dotCount) {
        this.mDotCount = dotCount;
        removeAllViews();
        for (int i = 0; i < dotCount; i++) {
            View view = LayoutInflater.from(getContext()).inflate(R.layout.ms_dot, this, false);
            addView(view);
        }
        setCurrent(0, false);
    }

    /**
     * Changes the currently selected dot and updates the UI accordingly
     * @param current the new currently selected dot
     * @param shouldAnimate true if the change should be animated, false otherwise
     */
    public void setCurrent(int current, boolean shouldAnimate) {
        this.mCurrent = current;
        update(shouldAnimate);
    }

    private void update(boolean shouldAnimate) {
        for (int i = 0; i < mDotCount; i++) {
            final AccelerateDecelerateInterpolator interpolator = new AccelerateDecelerateInterpolator();
            if (i == mCurrent) {
                getChildAt(i).animate().scaleX(FULL_SCALE).scaleY(FULL_SCALE)
                        .setDuration(shouldAnimate ? SCALE_ANIMATION_DEFAULT_DURATION : DURATION_IMMEDIATE)
                        .setInterpolator(interpolator).start();
                colorChildAtPosition(i, true);
            } else {
                getChildAt(i).animate().scaleX(HALF_SCALE).scaleY(HALF_SCALE)
                        .setDuration(shouldAnimate ? SCALE_ANIMATION_DEFAULT_DURATION : DURATION_IMMEDIATE)
                        .setInterpolator(interpolator).start();
                colorChildAtPosition(i, false);
            }
        }
    }

    private void colorChildAtPosition(int i, boolean selected) {
        Drawable d = getChildAt(i).getBackground();
        TintUtil.tintDrawable(d, selected ? mSelectedColor : mUnselectedColor);
    }

}