android - 带有 TabLayout 的 ViewPager 问题与 AnimatedVectorDrawable

Question

我正在尝试在 VectorDrawable 上实现带有一些动画的简单 ViewPager。
正在关注this very good example使用点切换的漂亮标签滚动的解决方案。

唯一的区别是我使用的是矢量动画。作为一项 Activity ，它就像一个魅力，添加了 ViewPager，动画不始终启动。

compileSdkVersion 25
buildToolsVersion "26.0.2"
targetSdkVersion 25

我正在我的设备 (SG7) 上调试，我在 animation.start()

上设置了断点

• 在中间屏幕上，并不总是调用断点
• 更频繁地出现在屏幕 1 和 3 上，不触发动画
• 使用点跳跃时，总是会触发 1 和 3 之间的动画!但不是在做 1-2 或 2-3 时!!

所有这些都在一个大的 VectorDrawable 上工作，其中有 3 个动画组。
2个字幕一开始就滑进去，然后无限滚动旋转，旋转一直有效。

Activity

   @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main_activity);

    mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

    // Set up the ViewPager with the sections adapter.
    mViewPager = (ViewPager) findViewById(R.id.pager);
    mHideHandler.post(mHidePart2Runnable);
    mViewPager.setAdapter(mSectionsPagerAdapter);

    TabLayout tabLayout = (TabLayout) findViewById(R.id.tabDots);
    tabLayout.setupWithViewPager(mViewPager, true);

    };

fragment :

  public class SectionsPagerAdapter extends FragmentPagerAdapter {

    public SectionsPagerAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int position) {
        // getItem is called to instantiate the fragment for the given page.
        // Return a PlaceholderFragment (defined as a static inner class below).
        return PlaceholderFragment.newInstance(position + 1);
    }

    @Override
    public int getCount() {
        // Show 3 total pages.
        return 3;
    }

静态 fragment

      public static class PlaceholderFragment extends Fragment {
    /**
     * The fragment argument representing the section number for this
     * fragment.
     */
    private static final String ARG_SECTION_NUMBER = "section_number";

    public PlaceholderFragment() {
    }

    /**
     * Returns a new instance of this fragment for the given section
     * number.
     */
    public static PlaceholderFragment newInstance(int sectionNumber) {
        PlaceholderFragment fragment = new PlaceholderFragment();
        Bundle args = new Bundle();
        args.putInt(ARG_SECTION_NUMBER, sectionNumber);
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.activity_fullscreen, container, false);
        View imgView = rootView.findViewById(R.id.vec_anim);

        Drawable drawable = ((ImageView)imgView).getDrawable();
        if (drawable instanceof Animatable) {
            ((Animatable) drawable).start();
        };
        return rootView;
    }

我是这一切的新手，想描述 SVG 大小对性能的影响(考虑缓存 svgs 并在创建 View 时触发动画可能......)我正在尝试优化它并使其成为现实光滑的。但首先，它不能正常工作。

为什么换页时断点不总是命中？
有更好的方法吗？

Answer 1

试试这个，

1. Add library compile com.mcxiaoke.viewpagerindicator:library:2.4.1@aar'.

2. Your main layout file,

    <RelativeLayout
        android:id="@+id/pager_layout"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:gravity="right">
        <android.support.v4.view.ViewPager
            android:id="@+id/pager_profile"
            android:layout_width="fill_parent"
            android:layout_height="match_parent"
            app:layout_behavior="@string/appbar_scrolling_view_behavior">
        </android.support.v4.view.ViewPager>
    
        <yourpackagename.utils.CirclePageIndicator
           android:id="@+id/cover_photo_indicator"
           android:layout_width="wrap_content"
           android:layout_height="wrap_content"
           android:foregroundGravity="right"
           android:layout_alignParentBottom="true"
           android:layout_alignParentEnd="true"
           android:padding="10dip" />
</RelativeLayout>

3. Create custom class CirclePageIndicator

/**
 * Draws circles (one for each view). The current view position is filled and
 * others are only stroked.
 */
public class CirclePageIndicator extends View implements PageIndicator {
    private static final int INVALID_POINTER = -1;

    private float mRadius;
    private final Paint mPaintPageFill = new Paint(ANTI_ALIAS_FLAG);
    private final Paint mPaintStroke = new Paint(ANTI_ALIAS_FLAG);
    private final Paint mPaintFill = new Paint(ANTI_ALIAS_FLAG);
    private ViewPager mViewPager;
    private ViewPager.OnPageChangeListener mListener;
    private int mCurrentPage;
    private int mSnapPage;
    private float mPageOffset;
    private int mScrollState;
    private int mOrientation;
    private boolean mCentered;
    private boolean mSnap;

    private int mTouchSlop;
    private float mLastMotionX = -1;
    private int mActivePointerId = INVALID_POINTER;
    private boolean mIsDragging;


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

    public CirclePageIndicator(Context context, AttributeSet attrs) {
        this(context, attrs, R.attr.vpiCirclePageIndicatorStyle);
    }

    public CirclePageIndicator(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        if (isInEditMode()) return;

        //Load defaults from resources
        final Resources res = getResources();
        final int defaultPageColor = res.getColor(R.color.default_circle_indicator_page_color);
        //default_circle_indicator_fill_color
        final int defaultFillColor = res.getColor(R.color.holo_blue_dark);
        final int defaultOrientation = res.getInteger(R.integer.default_circle_indicator_orientation);
        final int defaultStrokeColor = res.getColor(R.color.default_circle_indicator_stroke_color);
        final float defaultStrokeWidth = res.getDimension(R.dimen.default_circle_indicator_stroke_width);
        final float defaultRadius = res.getDimension(R.dimen.default_circle_indicator_radius);
        final boolean defaultCentered = res.getBoolean(R.bool.default_circle_indicator_centered);
        final boolean defaultSnap = res.getBoolean(R.bool.default_circle_indicator_snap);

        //Retrieve styles attributes
        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CirclePageIndicator, defStyle, 0);

        mCentered = a.getBoolean(R.styleable.CirclePageIndicator_centered, defaultCentered);
        mOrientation = a.getInt(R.styleable.CirclePageIndicator_android_orientation, defaultOrientation);
        mPaintPageFill.setStyle(Style.FILL);
        mPaintPageFill.setColor(a.getColor(R.styleable.CirclePageIndicator_pageColor, defaultPageColor));
        mPaintStroke.setStyle(Style.STROKE);
        mPaintStroke.setColor(a.getColor(R.styleable.CirclePageIndicator_strokeColor, defaultStrokeColor));
        mPaintStroke.setStrokeWidth(a.getDimension(R.styleable.CirclePageIndicator_strokeWidth, defaultStrokeWidth));
        mPaintFill.setStyle(Style.FILL);
        mPaintFill.setColor(a.getColor(R.styleable.CirclePageIndicator_fillColor, defaultFillColor));
        mRadius = a.getDimension(R.styleable.CirclePageIndicator_radius, defaultRadius);
        mSnap = a.getBoolean(R.styleable.CirclePageIndicator_snap, defaultSnap);

        Drawable background = a.getDrawable(R.styleable.CirclePageIndicator_android_background);
        if (background != null) {
            setBackgroundDrawable(background);
        }

        a.recycle();

        final ViewConfiguration configuration = ViewConfiguration.get(context);
        mTouchSlop = ViewConfigurationCompat.getScaledPagingTouchSlop(configuration);
    }


    public void setCentered(boolean centered) {
        mCentered = centered;
        invalidate();
    }

    public boolean isCentered() {
        return mCentered;
    }

    public void setPageColor(int pageColor) {
        mPaintPageFill.setColor(pageColor);
        invalidate();
    }

    public int getPageColor() {
        return mPaintPageFill.getColor();
    }

    public void setFillColor(int fillColor) {
        mPaintFill.setColor(fillColor);
        invalidate();
    }

    public int getFillColor() {
        return mPaintFill.getColor();
    }

    public void setOrientation(int orientation) {
        switch (orientation) {
            case HORIZONTAL:
            case VERTICAL:
                mOrientation = orientation;
                requestLayout();
                break;

            default:
                throw new IllegalArgumentException("Orientation must be either HORIZONTAL or VERTICAL.");
        }
    }

    public int getOrientation() {
        return mOrientation;
    }

    public void setStrokeColor(int strokeColor) {
        mPaintStroke.setColor(strokeColor);
        invalidate();
    }

    public int getStrokeColor() {
        return mPaintStroke.getColor();
    }

    public void setStrokeWidth(float strokeWidth) {
        mPaintStroke.setStrokeWidth(strokeWidth);
        invalidate();
    }

    public float getStrokeWidth() {
        return mPaintStroke.getStrokeWidth();
    }

    public void setRadius(float radius) {
        mRadius = radius;
        invalidate();
    }

    public float getRadius() {
        return mRadius;
    }

    public void setSnap(boolean snap) {
        mSnap = snap;
        invalidate();
    }

    public boolean isSnap() {
        return mSnap;
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        if (mViewPager == null) {
            return;
        }
        final int count = mViewPager.getAdapter().getCount();
        if (count == 0) {
            return;
        }

        if (mCurrentPage >= count) {
            setCurrentItem(count - 1);
            return;
        }

        int longSize;
        int longPaddingBefore;
        int longPaddingAfter;
        int shortPaddingBefore;
        if (mOrientation == HORIZONTAL) {
            longSize = getWidth();
            longPaddingBefore = getPaddingLeft();
            longPaddingAfter = getPaddingRight();
            shortPaddingBefore = getPaddingTop();
        } else {
            longSize = getHeight();
            longPaddingBefore = getPaddingTop();
            longPaddingAfter = getPaddingBottom();
            shortPaddingBefore = getPaddingLeft();
        }

        final float threeRadius = mRadius * 3;
        final float shortOffset = shortPaddingBefore + mRadius;
        float longOffset = longPaddingBefore + mRadius;
        if (mCentered) {
            longOffset += ((longSize - longPaddingBefore - longPaddingAfter) / 2.0f) - ((count * threeRadius) / 2.0f);
        }

        float dX;
        float dY;

        float pageFillRadius = mRadius;
        if (mPaintStroke.getStrokeWidth() > 0) {
            pageFillRadius -= mPaintStroke.getStrokeWidth() / 2.0f;
        }

        //Draw stroked circles
        for (int iLoop = 0; iLoop < count; iLoop++) {
            float drawLong = longOffset + (iLoop * threeRadius);
            if (mOrientation == HORIZONTAL) {
                dX = drawLong;
                dY = shortOffset;
            } else {
                dX = shortOffset;
                dY = drawLong;
            }
            // Only paint fill if not completely transparent
            if (mPaintPageFill.getAlpha() > 0) {
                canvas.drawCircle(dX, dY, pageFillRadius, mPaintPageFill);
            }

            // Only paint stroke if a stroke width was non-zero
            if (pageFillRadius != mRadius) {
                canvas.drawCircle(dX, dY, mRadius, mPaintStroke);
            }
        }

        //Draw the filled circle according to the current scroll
        float cx = (mSnap ? mSnapPage : mCurrentPage) * threeRadius;
        if (!mSnap) {
            cx += mPageOffset * threeRadius;
        }
        if (mOrientation == HORIZONTAL) {
            dX = longOffset + cx;
            dY = shortOffset;
        } else {
            dX = shortOffset;
            dY = longOffset + cx;
        }
        canvas.drawCircle(dX, dY, mRadius, mPaintFill);
    }

    public boolean onTouchEvent(android.view.MotionEvent ev) {
        if (super.onTouchEvent(ev)) {
            return true;
        }
        if ((mViewPager == null) || (mViewPager.getAdapter().getCount() == 0)) {
            return false;
        }

        final int action = ev.getAction() & MotionEventCompat.ACTION_MASK;
        switch (action) {
            case MotionEvent.ACTION_DOWN:
                mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
                mLastMotionX = ev.getX();
                break;

            case MotionEvent.ACTION_MOVE: {
                final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
                final float x = MotionEventCompat.getX(ev, activePointerIndex);
                final float deltaX = x - mLastMotionX;

                if (!mIsDragging) {
                    if (Math.abs(deltaX) > mTouchSlop) {
                        mIsDragging = true;
                    }
                }

                if (mIsDragging) {
                    mLastMotionX = x;
                    if (mViewPager.isFakeDragging() || mViewPager.beginFakeDrag()) {
                        mViewPager.fakeDragBy(deltaX);
                    }
                }

                break;
            }

            case MotionEvent.ACTION_CANCEL:
            case MotionEvent.ACTION_UP:
                if (!mIsDragging) {
                    final int count = mViewPager.getAdapter().getCount();
                    final int width = getWidth();
                    final float halfWidth = width / 2f;
                    final float sixthWidth = width / 6f;

                    if ((mCurrentPage > 0) && (ev.getX() < halfWidth - sixthWidth)) {
                        if (action != MotionEvent.ACTION_CANCEL) {
                            mViewPager.setCurrentItem(mCurrentPage - 1);
                        }
                        return true;
                    } else if ((mCurrentPage < count - 1) && (ev.getX() > halfWidth + sixthWidth)) {
                        if (action != MotionEvent.ACTION_CANCEL) {
                            mViewPager.setCurrentItem(mCurrentPage + 1);
                        }
                        return true;
                    }
                }

                mIsDragging = false;
                mActivePointerId = INVALID_POINTER;
                if (mViewPager.isFakeDragging()) mViewPager.endFakeDrag();
                break;

            case MotionEventCompat.ACTION_POINTER_DOWN: {
                final int index = MotionEventCompat.getActionIndex(ev);
                mLastMotionX = MotionEventCompat.getX(ev, index);
                mActivePointerId = MotionEventCompat.getPointerId(ev, index);
                break;
            }

            case MotionEventCompat.ACTION_POINTER_UP:
                final int pointerIndex = MotionEventCompat.getActionIndex(ev);
                final int pointerId = MotionEventCompat.getPointerId(ev, pointerIndex);
                if (pointerId == mActivePointerId) {
                    final int newPointerIndex = pointerIndex == 0 ? 1 : 0;
                    mActivePointerId = MotionEventCompat.getPointerId(ev, newPointerIndex);
                }
                mLastMotionX = MotionEventCompat.getX(ev, MotionEventCompat.findPointerIndex(ev, mActivePointerId));
                break;
        }

        return true;
    }

    @Override
    public void setViewPager(ViewPager view) {
        if (mViewPager == view) {
            return;
        }
        if (mViewPager != null) {
            mViewPager.setOnPageChangeListener(null);
        }
        if (view.getAdapter() == null) {
            throw new IllegalStateException("ViewPager does not have adapter instance.");
        }
        mViewPager = view;
        mViewPager.setOnPageChangeListener(this);
        invalidate();
    }

    @Override
    public void setViewPager(ViewPager view, int initialPosition) {
        setViewPager(view);
        setCurrentItem(initialPosition);
    }

    @Override
    public void setCurrentItem(int item) {
        if (mViewPager == null) {
            throw new IllegalStateException("ViewPager has not been bound.");
        }
        mViewPager.setCurrentItem(item);
        mCurrentPage = item;
        invalidate();
    }

    @Override
    public void notifyDataSetChanged() {
        invalidate();
    }

    @Override
    public void onPageScrollStateChanged(int state) {
        mScrollState = state;

        if (mListener != null) {
            mListener.onPageScrollStateChanged(state);
        }
    }

    @Override
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
        mCurrentPage = position;
        mPageOffset = positionOffset;
        invalidate();

        if (mListener != null) {
            mListener.onPageScrolled(position, positionOffset, positionOffsetPixels);
        }
    }

    @Override
    public void onPageSelected(int position) {
        if (mSnap || mScrollState == ViewPager.SCROLL_STATE_IDLE) {
            mCurrentPage = position;
            mSnapPage = position;
            invalidate();
        }

        if (mListener != null) {
            mListener.onPageSelected(position);
        }
    }

    @Override
    public void setOnPageChangeListener(ViewPager.OnPageChangeListener listener) {
        mListener = listener;
    }

    /*
     * (non-Javadoc)
     *
     * @see android.view.View#onMeasure(int, int)
     */
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        if (mOrientation == HORIZONTAL) {
            setMeasuredDimension(measureLong(widthMeasureSpec), measureShort(heightMeasureSpec));
        } else {
            setMeasuredDimension(measureShort(widthMeasureSpec), measureLong(heightMeasureSpec));
        }
    }

    /**
     * Determines the width of this view
     *
     * @param measureSpec
     *            A measureSpec packed into an int
     * @return The width of the view, honoring constraints from measureSpec
     */
    private int measureLong(int measureSpec) {
        int result;
        int specMode = MeasureSpec.getMode(measureSpec);
        int specSize = MeasureSpec.getSize(measureSpec);

        if ((specMode == MeasureSpec.EXACTLY) || (mViewPager == null)) {
            //We were told how big to be
            result = specSize;
        } else {
            //Calculate the width according the views count
            final int count = mViewPager.getAdapter().getCount();
            result = (int)(getPaddingLeft() + getPaddingRight()
                    + (count * 2 * mRadius) + (count - 1) * mRadius + 1);
            //Respect AT_MOST value if that was what is called for by measureSpec
            if (specMode == MeasureSpec.AT_MOST) {
                result = Math.min(result, specSize);
            }
        }
        return result;
    }

    /**
     * Determines the height of this view
     *
     * @param measureSpec
     *            A measureSpec packed into an int
     * @return The height of the view, honoring constraints from measureSpec
     */
    private int measureShort(int measureSpec) {
        int result;
        int specMode = MeasureSpec.getMode(measureSpec);
        int specSize = MeasureSpec.getSize(measureSpec);

        if (specMode == MeasureSpec.EXACTLY) {
            //We were told how big to be
            result = specSize;
        } else {
            //Measure the height
            result = (int)(2 * mRadius + getPaddingTop() + getPaddingBottom() + 1);
            //Respect AT_MOST value if that was what is called for by measureSpec
            if (specMode == MeasureSpec.AT_MOST) {
                result = Math.min(result, specSize);
            }
        }
        return result;
    }

    @Override
    public void onRestoreInstanceState(Parcelable state) {
        SavedState savedState = (SavedState)state;
        super.onRestoreInstanceState(savedState.getSuperState());
        mCurrentPage = savedState.currentPage;
        mSnapPage = savedState.currentPage;
        requestLayout();
    }

    @Override
    public Parcelable onSaveInstanceState() {
        Parcelable superState = super.onSaveInstanceState();
        SavedState savedState = new SavedState(superState);
        savedState.currentPage = mCurrentPage;
        return savedState;
    }

    static class SavedState extends BaseSavedState {
        int currentPage;

        public SavedState(Parcelable superState) {
            super(superState);
        }

        private SavedState(Parcel in) {
            super(in);
            currentPage = in.readInt();
        }

        @Override
        public void writeToParcel(Parcel dest, int flags) {
            super.writeToParcel(dest, flags);
            dest.writeInt(currentPage);
        }

        @SuppressWarnings("UnusedDeclaration")
        public static final Parcelable.Creator<SavedState> CREATOR = new Parcelable.Creator<SavedState>() {
            @Override
            public SavedState createFromParcel(Parcel in) {
                return new SavedState(in);
            }

            @Override
            public SavedState[] newArray(int size) {
                return new SavedState[size];
            }
        };
    }
}

4. Create indicator_tags.xml inside res -> values

---

<resources>

    <bool name="default_circle_indicator_centered">true</bool>

    <color name="default_circle_indicator_fill_color">#FFFF0000</color>
    <color name="default_circle_indicator_page_color">#00000000</color>

    <integer name="default_circle_indicator_orientation">0</integer>

    <dimen name="default_circle_indicator_radius">4dp</dimen>

    <bool name="default_circle_indicator_snap">false</bool>

    <color name="default_circle_indicator_stroke_color">#FFDDDDDD</color>

    <dimen name="default_circle_indicator_stroke_width">1dp</dimen>

    <declare-styleable name="ViewPagerIndicator">

        <!-- Style of the circle indicator. -->
        <attr name="vpiCirclePageIndicatorStyle" format="reference" />
        <!-- Style of the icon indicator's views. -->
        <attr name="vpiIconPageIndicatorStyle" format="reference" />
        <!-- Style of the line indicator. -->
        <attr name="vpiLinePageIndicatorStyle" format="reference" />
        <!-- Style of the title indicator. -->
        <attr name="vpiTitlePageIndicatorStyle" format="reference" />
        <!-- Style of the tab indicator's tabs. -->
        <attr name="vpiTabPageIndicatorStyle" format="reference" />
        <!-- Style of the underline indicator. -->
        <attr name="vpiUnderlinePageIndicatorStyle" format="reference" />
    </declare-styleable>

    <attr name="centered" format="boolean" />
    <attr name="selectedColor" format="color" />
    <attr name="strokeWidth" format="dimension" />
    <attr name="unselectedColor" format="color" />

    <declare-styleable name="CirclePageIndicator">

        <!-- Whether or not the indicators should be centered. -->
        <attr name="centered" />
        <!-- Color of the filled circle that represents the current page. -->
        <attr name="fillColor" format="color" />
        <!-- Color of the filled circles that represents pages. -->
        <attr name="pageColor" format="color" />
        <!-- Orientation of the indicator. -->
        <attr name="android:orientation" />
        <!-- Radius of the circles. This is also the spacing between circles. -->
        <attr name="radius" format="dimension" />
        <!-- Whether or not the selected indicator snaps to the circles. -->
        <attr name="snap" format="boolean" />
        <!-- Color of the open circles. -->
        <attr name="strokeColor" format="color" />
        <!-- Width of the stroke used to draw the circles. -->
        <attr name="strokeWidth" />
        <!-- View background -->
        <attr name="android:background" />
    </declare-styleable>
    <declare-styleable name="LinePageIndicator">

        <!-- Whether or not the indicators should be centered. -->
        <attr name="centered" />
        <!-- Color of the unselected lines that represent the pages. -->
        <attr name="unselectedColor" />
        <!-- Color of the selected line that represents the current page. -->
        <attr name="selectedColor" />
        <!-- Width of each indicator line. -->
        <attr name="lineWidth" format="dimension" />
        <!-- Width of each indicator line's stroke. -->
        <attr name="strokeWidth" />
        <!-- Width of the gap between each indicator line. -->
        <attr name="gapWidth" format="dimension" />
        <!-- View background -->
        <attr name="android:background" />
    </declare-styleable>
    <declare-styleable name="TitlePageIndicator">

        <!-- Screen edge padding. -->
        <attr name="clipPadding" format="dimension" />
        <!-- Color of the footer line and indicator. -->
        <attr name="footerColor" format="color" />
        <!-- Height of the footer line. -->
        <attr name="footerLineHeight" format="dimension" />
        <!-- Style of the indicator. Default is triangle. -->
        <attr name="footerIndicatorStyle">
            <enum name="none" value="0" />
            <enum name="triangle" value="1" />
            <enum name="underline" value="2" />
        </attr>
        <!-- Height of the indicator above the footer line. -->
        <attr name="footerIndicatorHeight" format="dimension" />
        <!-- Left and right padding of the underline indicator. -->
        <attr name="footerIndicatorUnderlinePadding" format="dimension" />
        <!-- Padding between the bottom of the title and the footer. -->
        <attr name="footerPadding" format="dimension" />
        <!-- Position of the line. -->
        <attr name="linePosition">
            <enum name="bottom" value="0" />
            <enum name="top" value="1" />
        </attr>
        <!-- Color of the selected title. -->
        <attr name="selectedColor" />
        <!-- Whether or not the selected item is displayed as bold. -->
        <attr name="selectedBold" format="boolean" />
        <!-- Color of regular titles. -->
        <attr name="android:textColor" />
        <!-- Size of title text. -->
        <attr name="android:textSize" />
        <!-- Padding between titles when bumping into each other. -->
        <attr name="titlePadding" format="dimension" />
        <!-- Padding between titles and the top of the View. -->
        <attr name="topPadding" format="dimension" />
        <!-- View background -->
        <attr name="android:background" />
    </declare-styleable>
    <declare-styleable name="UnderlinePageIndicator">

        <!-- Whether or not the selected indicator fades. -->
        <attr name="fades" format="boolean" />
        <!-- Length of the delay to fade the indicator. -->
        <attr name="fadeDelay" format="integer" />
        <!-- Length of the indicator fade to transparent. -->
        <attr name="fadeLength" format="integer" />
        <!-- Color of the selected line that represents the current page. -->
        <attr name="selectedColor" />
        <!-- View background -->
        <attr name="android:background" />
    </declare-styleable>

</resources>  

5. Call this from MainActivity like

    // setup the view pager with its adapter
    vpagerProfile.setAdapter(objProfilePageTopListAdapter);
    
    // initialize circular indicator class
    mCirclePageIndicator = (CirclePageIndicator)findViewById(R.id.cover_photo_indicator);
    
    mCirclePageIndicator.setPageColor(android.R.color.transparent);
    
    // set viewpager to indicator so it can indicate when you change the page
    mCirclePageIndicator.setViewPager(vpagerProfile);