Example usage for android.view Gravity CENTER

Introduction

In this page you can find the example usage for android.view Gravity CENTER_HORIZONTAL.

Prototype

int CENTER_HORIZONTAL

To view the source code for android.view Gravity CENTER_HORIZONTAL.

Click Source Link

Document

Place object in the horizontal center of its container, not changing its size.

Usage

From source file:com.guide.ViewPager.java

@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
    final int count = getChildCount();
    int width = r - l;
    int height = b - t;
    int paddingLeft = getPaddingLeft();
    int paddingTop = getPaddingTop();
    int paddingRight = getPaddingRight();
    int paddingBottom = getPaddingBottom();
    final int scrollX = getScrollX();
    final int scrollY = getScrollY();

    int decorCount = 0;

    // First pass - decor views. We need to do this in two passes so that
    // we have the proper offsets for non-decor views later.
    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            int childLeft = 0;
            int childTop = 0;
            if (lp.isDecor) {
                final int hgrav = lp.gravity & Gravity.HORIZONTAL_GRAVITY_MASK;
                final int vgrav = lp.gravity & Gravity.VERTICAL_GRAVITY_MASK;
                switch (hgrav) {
                default:
                    childLeft = paddingLeft;
                    break;
                case Gravity.LEFT:
                    childLeft = paddingLeft;
                    paddingLeft += child.getMeasuredWidth();
                    break;
                case Gravity.CENTER_HORIZONTAL:
                    childLeft = Math.max((width - child.getMeasuredWidth()) / 2, paddingLeft);
                    break;
                case Gravity.RIGHT:
                    childLeft = width - paddingRight - child.getMeasuredWidth();
                    paddingRight += child.getMeasuredWidth();
                    break;
                }/*from ww w .  ja va2 s  . c  o  m*/
                switch (vgrav) {
                default:
                    childTop = paddingTop;
                    break;
                case Gravity.TOP:
                    childTop = paddingTop;
                    paddingTop += child.getMeasuredHeight();
                    break;
                case Gravity.CENTER_VERTICAL:
                    childTop = Math.max((height - child.getMeasuredHeight()) / 2, paddingTop);
                    break;
                case Gravity.BOTTOM:
                    childTop = height - paddingBottom - child.getMeasuredHeight();
                    paddingBottom += child.getMeasuredHeight();
                    break;
                }
                if (isOrientationHorizontal()) {
                    childLeft += scrollX;
                } else {
                    childTop += scrollY;
                }
                child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());
                decorCount++;
            }
        }
    }

    int childSize = 0;
    if (isOrientationHorizontal()) {
        childSize = width - paddingLeft - paddingRight;
    } else {
        childSize = height - paddingTop - paddingBottom;
    }
    // Page views. Do this once we have the right padding offsets from
    // above.
    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            ItemInfo ii;
            if (!lp.isDecor && (ii = infoForChild(child)) != null) {
                int loff = (int) (childSize * ii.offset);
                int childLeft = paddingLeft + (isOrientationHorizontal() ? loff : 0);
                int childTop = paddingTop + (isOrientationHorizontal() ? 0 : loff);
                if (lp.needsMeasure) {
                    // This was added during layout and needs measurement.
                    // Do it now that we know what we're working with.
                    lp.needsMeasure = false;
                    int widthSpec = 0, heightSpec = 0;
                    if (isOrientationHorizontal()) {
                        widthSpec = MeasureSpec.makeMeasureSpec((int) (childSize * lp.sizeFactor),
                                MeasureSpec.EXACTLY);
                        heightSpec = MeasureSpec.makeMeasureSpec((int) (height - paddingTop - paddingBottom),
                                MeasureSpec.EXACTLY);
                    } else {
                        widthSpec = MeasureSpec.makeMeasureSpec((int) (width - paddingLeft - paddingRight),
                                MeasureSpec.EXACTLY);
                        heightSpec = MeasureSpec.makeMeasureSpec((int) (childSize * lp.sizeFactor),
                                MeasureSpec.EXACTLY);
                    }
                    child.measure(widthSpec, heightSpec);
                }
                if (DEBUG)
                    Log.v(TAG, "Positioning #" + i + " " + child + " f=" + ii.object + ":" + childLeft + ","
                            + childTop + " " + child.getMeasuredWidth() + "x" + child.getMeasuredHeight());
                child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());
            }
        }
    }
    mLeftPageBounds = paddingLeft;
    mTopPageBounds = paddingTop;
    mRightPageBounds = width - paddingRight;
    mBottomPageBounds = height - paddingBottom;
    mDecorChildCount = decorCount;

    if (mFirstLayout) {
        scrollToItem(mCurItem, false, 0, false);
    }
    mFirstLayout = false;
}

From source file:com.isapp.android.circularviewpager.CircularViewPager.java

@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
    final int count = getChildCount();
    int width = r - l;
    int height = b - t;
    int paddingLeft = getPaddingLeft();
    int paddingTop = getPaddingTop();
    int paddingRight = getPaddingRight();
    int paddingBottom = getPaddingBottom();
    final int scrollX = getScrollX();
    int decorCount = 0;
    // First pass - decor views. We need to do this in two passes so that
    // we have the proper offsets for non-decor views later.
    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            int childLeft = 0;
            int childTop = 0;
            if (lp.isDecor) {
                final int hgrav = lp.gravity & Gravity.HORIZONTAL_GRAVITY_MASK;
                final int vgrav = lp.gravity & Gravity.VERTICAL_GRAVITY_MASK;
                switch (hgrav) {
                default:
                    childLeft = paddingLeft;
                    break;
                case Gravity.LEFT:
                    childLeft = paddingLeft;
                    paddingLeft += child.getMeasuredWidth();
                    break;
                case Gravity.CENTER_HORIZONTAL:
                    childLeft = Math.max((width - child.getMeasuredWidth()) / 2, paddingLeft);
                    break;
                case Gravity.RIGHT:
                    childLeft = width - paddingRight - child.getMeasuredWidth();
                    paddingRight += child.getMeasuredWidth();
                    break;
                }//from   ww w .j  av a  2  s .  co  m
                switch (vgrav) {
                default:
                    childTop = paddingTop;
                    break;
                case Gravity.TOP:
                    childTop = paddingTop;
                    paddingTop += child.getMeasuredHeight();
                    break;
                case Gravity.CENTER_VERTICAL:
                    childTop = Math.max((height - child.getMeasuredHeight()) / 2, paddingTop);
                    break;
                case Gravity.BOTTOM:
                    childTop = height - paddingBottom - child.getMeasuredHeight();
                    paddingBottom += child.getMeasuredHeight();
                    break;
                }
                childLeft += scrollX;
                child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());
                decorCount++;
            }
        }
    }
    final int childWidth = width - paddingLeft - paddingRight;
    // Page views. Do this once we have the right padding offsets from above.
    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            ItemInfo ii;
            if (!lp.isDecor && (ii = infoForChild(child)) != null) {
                int loff = (int) (childWidth * ii.offset);
                int childLeft = paddingLeft + loff;
                int childTop = paddingTop;
                if (lp.needsMeasure) {
                    // This was added during layout and needs measurement.
                    // Do it now that we know what we're working with.
                    lp.needsMeasure = false;
                    final int widthSpec = MeasureSpec.makeMeasureSpec((int) (childWidth * lp.widthFactor),
                            MeasureSpec.EXACTLY);
                    final int heightSpec = MeasureSpec
                            .makeMeasureSpec((int) (height - paddingTop - paddingBottom), MeasureSpec.EXACTLY);
                    child.measure(widthSpec, heightSpec);
                }
                if (DEBUG)
                    Log.v(TAG, "Positioning #" + i + " " + child + " f=" + ii.object + ":" + childLeft + ","
                            + childTop + " " + child.getMeasuredWidth() + "x" + child.getMeasuredHeight());
                child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());
            }
        }
    }
    mTopPageBounds = paddingTop;
    mBottomPageBounds = height - paddingBottom;
    mDecorChildCount = decorCount;
    if (mFirstLayout) {
        scrollToItem(mCurItem, false, 0, false);
    }
    mFirstLayout = false;
}

From source file:com.telerik.examples.primitives.ExampleViewPagerBase.java

@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
    final int count = getChildCount();
    int width = r - l;
    int height = b - t;
    int paddingLeft = getPaddingLeft();
    int paddingTop = getPaddingTop();
    int paddingRight = getPaddingRight();
    int paddingBottom = getPaddingBottom();
    final int scrollPosition = getScroll(this);

    int decorCount = 0;

    // First pass - decor views. We need to do this in two passes so that
    // we have the proper offsets for non-decor views later.
    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            int childLeft = 0;
            int childTop = 0;
            if (lp.isDecor) {
                final int hgrav = lp.gravity & Gravity.HORIZONTAL_GRAVITY_MASK;
                final int vgrav = lp.gravity & Gravity.VERTICAL_GRAVITY_MASK;
                switch (hgrav) {
                default:
                    childLeft = paddingLeft;
                    break;
                case Gravity.LEFT:
                    childLeft = paddingLeft;
                    paddingLeft += child.getMeasuredWidth();
                    break;
                case Gravity.CENTER_HORIZONTAL:
                    childLeft = Math.max((width - child.getMeasuredWidth()) / 2, paddingLeft);
                    break;
                case Gravity.RIGHT:
                    childLeft = width - paddingRight - child.getMeasuredWidth();
                    paddingRight += child.getMeasuredWidth();
                    break;
                }// ww w . j  a v a2 s  .  c  o m
                switch (vgrav) {
                default:
                    childTop = paddingTop;
                    break;
                case Gravity.TOP:
                    childTop = paddingTop;
                    paddingTop += child.getMeasuredHeight();
                    break;
                case Gravity.CENTER_VERTICAL:
                    childTop = Math.max((height - child.getMeasuredHeight()) / 2, paddingTop);
                    break;
                case Gravity.BOTTOM:
                    childTop = height - paddingBottom - child.getMeasuredHeight();
                    paddingBottom += child.getMeasuredHeight();
                    break;
                }
                if (this.orientation == LinearLayout.HORIZONTAL) {
                    childLeft += scrollPosition;
                } else {
                    childTop += scrollPosition;
                }

                child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());
                decorCount++;
            }
        }
    }

    final int childLength = this.orientation == LinearLayout.HORIZONTAL ? width - paddingLeft - paddingRight
            : height - paddingTop - paddingBottom;
    // Page views. Do this once we have the right padding offsets from above.
    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            ItemInfo ii;
            if (!lp.isDecor && (ii = infoForChild(child)) != null) {
                int loff = (int) (childLength * ii.offset);
                int childLeft = paddingLeft;
                int childTop = paddingTop;

                if (this.orientation == LinearLayout.HORIZONTAL) {
                    childLeft += loff;
                } else {
                    childTop += loff;
                }
                if (lp.needsMeasure) {
                    // This was added during layout and needs measurement.
                    // Do it now that we know what we're working with.
                    lp.needsMeasure = false;
                    final int widthSpec;
                    final int heightSpec;

                    if (this.orientation == LinearLayout.HORIZONTAL) {
                        widthSpec = MeasureSpec.makeMeasureSpec((int) (childLength * lp.widthFactor),
                                MeasureSpec.EXACTLY);
                        heightSpec = MeasureSpec.makeMeasureSpec((int) (height - paddingTop - paddingBottom),
                                MeasureSpec.EXACTLY);
                    } else {
                        widthSpec = MeasureSpec.makeMeasureSpec((int) (width - paddingLeft - paddingRight),
                                MeasureSpec.EXACTLY);
                        heightSpec = MeasureSpec.makeMeasureSpec((int) (childLength * lp.widthFactor),
                                MeasureSpec.EXACTLY);
                    }

                    child.measure(widthSpec, heightSpec);
                }
                if (DEBUG)
                    Log.v(TAG, "Positioning #" + i + " " + child + " f=" + ii.object + ":" + childLeft + ","
                            + childTop + " " + child.getMeasuredWidth() + "x" + child.getMeasuredHeight());
                child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());
            }
        }
    }
    mTopPageBounds = paddingTop;
    mLeftPageBounds = paddingLeft;
    mBottomPageBounds = height - paddingBottom;
    mDecorChildCount = decorCount;

    if (mFirstLayout) {
        scrollToItem(mCurItem, false, 0, false);
    }
    mFirstLayout = false;
}

From source file:com.ifnoif.androidtestdemo.customview.VViewPager.java

@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
    final int count = getChildCount();
    int width = r - l;
    int height = b - t;
    int paddingLeft = getPaddingLeft();
    int paddingTop = getPaddingTop();
    int paddingRight = getPaddingRight();
    int paddingBottom = getPaddingBottom();
    final int scrollY = getScrollY();

    int decorCount = 0;

    // First pass - decor views. We need to do this in two passes so that
    // we have the proper offsets for non-decor views later.
    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            int childLeft = 0;
            int childTop = 0;
            if (lp.isDecor) {
                final int hgrav = lp.gravity & Gravity.HORIZONTAL_GRAVITY_MASK;
                final int vgrav = lp.gravity & Gravity.VERTICAL_GRAVITY_MASK;
                switch (hgrav) {
                default:
                    childLeft = paddingLeft;
                    break;
                case Gravity.LEFT:
                    childLeft = paddingLeft;
                    paddingLeft += child.getMeasuredWidth();
                    break;
                case Gravity.CENTER_HORIZONTAL:
                    childLeft = Math.max((width - child.getMeasuredWidth()) / 2, paddingLeft);
                    break;
                case Gravity.RIGHT:
                    childLeft = width - paddingRight - child.getMeasuredWidth();
                    paddingRight += child.getMeasuredWidth();
                    break;
                }//  ww w  . jav  a2 s  . c o m
                switch (vgrav) {
                default:
                    childTop = paddingTop;
                    break;
                case Gravity.TOP:
                    childTop = paddingTop;
                    paddingTop += child.getMeasuredHeight();
                    break;
                case Gravity.CENTER_VERTICAL:
                    childTop = Math.max((height - child.getMeasuredHeight()) / 2, paddingTop);
                    break;
                case Gravity.BOTTOM:
                    childTop = height - paddingBottom - child.getMeasuredHeight();
                    paddingBottom += child.getMeasuredHeight();
                    break;
                }
                childTop += scrollY;
                child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());
                decorCount++;
            }
        }
    }

    final int childHeight = height - paddingTop - paddingBottom;
    // Page views. Do this once we have the right padding offsets from above.
    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            ItemInfo ii;
            if (!lp.isDecor && (ii = infoForChild(child)) != null) {
                int toff = (int) (childHeight * ii.offset);
                int childTop = paddingTop + toff;
                int childLeft = paddingLeft;
                if (lp.needsMeasure) {
                    // This was added during layout and needs measurement.
                    // Do it now that we know what we're working with.
                    lp.needsMeasure = false;
                    final int widthSpec = MeasureSpec
                            .makeMeasureSpec((int) (width - paddingLeft - paddingRight), MeasureSpec.EXACTLY);
                    final int heightSpec = MeasureSpec.makeMeasureSpec((int) (childHeight * lp.heightFactor),
                            MeasureSpec.EXACTLY);
                    child.measure(widthSpec, heightSpec);
                }
                if (DEBUG)
                    Log.v(TAG, "Positioning #" + i + " " + child + " f=" + ii.object + ":" + childLeft + ","
                            + childTop + " " + child.getMeasuredWidth() + "x" + child.getMeasuredHeight());
                child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());
            }
        }
    }
    mLeftPageBounds = paddingLeft;
    mRightPageBounds = width - paddingRight;
    mDecorChildCount = decorCount;

    if (mFirstLayout) {
        scrollToItem(mCurItem, false, 0, false);
    }
    mFirstLayout = false;
}

From source file:com.example.leelay.galleyviewpager.GalleyViewPager.java

@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
    final int count = getChildCount();
    int width = r - l;
    int height = b - t;
    int paddingLeft = getPaddingLeft();
    int paddingTop = getPaddingTop();
    int paddingRight = getPaddingRight();
    int paddingBottom = getPaddingBottom();
    final int scrollX = getScrollX();

    int decorCount = 0;

    // First pass - decor views. We need to do this in two passes so that
    // we have the proper offsets for non-decor views later.
    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            int childLeft = 0;
            int childTop = 0;
            if (lp.isDecor) {
                final int hgrav = lp.gravity & Gravity.HORIZONTAL_GRAVITY_MASK;
                final int vgrav = lp.gravity & Gravity.VERTICAL_GRAVITY_MASK;
                switch (hgrav) {
                default:
                    childLeft = paddingLeft;
                    break;
                case Gravity.LEFT:
                    childLeft = paddingLeft;
                    paddingLeft += child.getMeasuredWidth();
                    break;
                case Gravity.CENTER_HORIZONTAL:
                    childLeft = Math.max((width - child.getMeasuredWidth()) / 2, paddingLeft);
                    break;
                case Gravity.RIGHT:
                    childLeft = width - paddingRight - child.getMeasuredWidth();
                    paddingRight += child.getMeasuredWidth();
                    break;
                }/* w  ww  . j av  a  2  s. c o  m*/
                switch (vgrav) {
                default:
                    childTop = paddingTop;
                    break;
                case Gravity.TOP:
                    childTop = paddingTop;
                    paddingTop += child.getMeasuredHeight();
                    break;
                case Gravity.CENTER_VERTICAL:
                    childTop = Math.max((height - child.getMeasuredHeight()) / 2, paddingTop);
                    break;
                case Gravity.BOTTOM:
                    childTop = height - paddingBottom - child.getMeasuredHeight();
                    paddingBottom += child.getMeasuredHeight();
                    break;
                }
                childLeft += scrollX;
                child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());
                decorCount++;
            }
        }
    }

    final int childWidth = (width - paddingLeft - paddingRight) - mEndWidth - mPageMargin;
    // Page views. Do this once we have the right padding offsets from above.
    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            ItemInfo ii;
            if (!lp.isDecor && (ii = infoForChild(child)) != null) {
                int loff = (int) (childWidth * ii.offset);
                int childLeft = paddingLeft + loff;
                int childTop = paddingTop;
                if (lp.needsMeasure) {
                    // This was added during layout and needs measurement.
                    // Do it now that we know what we're working with.
                    lp.needsMeasure = false;
                    final int widthSpec = MeasureSpec.makeMeasureSpec((int) (childWidth * lp.widthFactor),
                            MeasureSpec.EXACTLY);
                    final int heightSpec = MeasureSpec
                            .makeMeasureSpec((int) (height - paddingTop - paddingBottom), MeasureSpec.EXACTLY);
                    child.measure(widthSpec, heightSpec);
                }
                if (DEBUG)
                    Log.v(TAG, "Positioning #" + i + " " + child + " f=" + ii.object + ":" + childLeft + ","
                            + childTop + " " + child.getMeasuredWidth() + "x" + child.getMeasuredHeight());
                child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());
            }
        }
    }
    mTopPageBounds = paddingTop;
    mBottomPageBounds = height - paddingBottom;
    mDecorChildCount = decorCount;

    if (mFirstLayout) {
        scrollToItem(mCurItem, false, 0, false);
    }
    mFirstLayout = false;
}

From source file:android.support.v7.widget.Toolbar.java

private int getChildHorizontalGravity(int gravity) {
    final int ld = ViewCompat.getLayoutDirection(this);
    final int absGrav = GravityCompat.getAbsoluteGravity(gravity, ld);
    final int hGrav = absGrav & Gravity.HORIZONTAL_GRAVITY_MASK;
    switch (hGrav) {
    case Gravity.LEFT:
    case Gravity.RIGHT:
    case Gravity.CENTER_HORIZONTAL:
        return hGrav;
    default:/*from   w w w .  j av  a2 s.c  o m*/
        return ld == ViewCompat.LAYOUT_DIRECTION_RTL ? Gravity.RIGHT : Gravity.LEFT;
    }
}

From source file:example.luojing.androidsourceanalysis.ViewPager.java

/**
 * ?View?//from  w w  w.  j  a  v  a  2  s  .c om
 */
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
    final int count = getChildCount();
    int width = r - l;
    int height = b - t;
    int paddingLeft = getPaddingLeft();
    int paddingTop = getPaddingTop();
    int paddingRight = getPaddingRight();
    int paddingBottom = getPaddingBottom();
    final int scrollX = getScrollX();

    int decorCount = 0;

    // First pass - decor views. We need to do this in two passes so that
    // we have the proper offsets for non-decor views later.
    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            int childLeft = 0;
            int childTop = 0;
            if (lp.isDecor) {
                final int hgrav = lp.gravity & Gravity.HORIZONTAL_GRAVITY_MASK;
                final int vgrav = lp.gravity & Gravity.VERTICAL_GRAVITY_MASK;
                switch (hgrav) {
                default:
                    childLeft = paddingLeft;
                    break;
                case Gravity.LEFT:
                    childLeft = paddingLeft;
                    paddingLeft += child.getMeasuredWidth();
                    break;
                case Gravity.CENTER_HORIZONTAL:
                    childLeft = Math.max((width - child.getMeasuredWidth()) / 2, paddingLeft);
                    break;
                case Gravity.RIGHT:
                    childLeft = width - paddingRight - child.getMeasuredWidth();
                    paddingRight += child.getMeasuredWidth();
                    break;
                }
                switch (vgrav) {
                default:
                    childTop = paddingTop;
                    break;
                case Gravity.TOP:
                    childTop = paddingTop;
                    paddingTop += child.getMeasuredHeight();
                    break;
                case Gravity.CENTER_VERTICAL:
                    childTop = Math.max((height - child.getMeasuredHeight()) / 2, paddingTop);
                    break;
                case Gravity.BOTTOM:
                    childTop = height - paddingBottom - child.getMeasuredHeight();
                    paddingBottom += child.getMeasuredHeight();
                    break;
                }
                childLeft += scrollX;
                child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());
                decorCount++;
            }
        }
    }

    final int childWidth = width - paddingLeft - paddingRight;
    // Page views. Do this once we have the right padding offsets from above.
    for (int i = 0; i < count; i++) {
        final View child = getChildAt(i);
        if (child.getVisibility() != GONE) {
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            ItemInfo ii;
            if (!lp.isDecor && (ii = infoForChild(child)) != null) {
                int loff = (int) (childWidth * ii.offset);
                int childLeft = paddingLeft + loff;
                int childTop = paddingTop;
                if (lp.needsMeasure) {
                    // This was added during layout and needs measurement.
                    // Do it now that we know what we're working with.
                    lp.needsMeasure = false;
                    final int widthSpec = MeasureSpec.makeMeasureSpec((int) (childWidth * lp.widthFactor),
                            MeasureSpec.EXACTLY);
                    final int heightSpec = MeasureSpec
                            .makeMeasureSpec((int) (height - paddingTop - paddingBottom), MeasureSpec.EXACTLY);
                    child.measure(widthSpec, heightSpec);
                }
                if (DEBUG) {
                    Log.v(TAG, "Positioning #" + i + " " + child + " f=" + ii.object + ":" + childLeft + ","
                            + childTop + " " + child.getMeasuredWidth() + "x" + child.getMeasuredHeight());
                }
                child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());
            }
        }
    }
    mTopPageBounds = paddingTop;
    mBottomPageBounds = height - paddingBottom;
    mDecorChildCount = decorCount;

    if (mFirstLayout) {
        scrollToItem(mCurItem, false, 0, false);
    }
    mFirstLayout = false;
}

From source file:com.suning.boxcontroller.control.ExViewPager.java

/**
 * This method will be invoked when the current page is scrolled, either as part of a programmatically initiated
 * smooth scroll or a user initiated touch scroll. If you override this method you must call through to the
 * superclass implementation (e.g. super.onPageScrolled(position, offset, offsetPixels)) before onPageScrolled
 * returns./*  w  w w. j a va  2s .co m*/
 *
 * @param position Position index of the first page currently being displayed. Page position+1 will be visible if
 *            positionOffset is nonzero.
 * @param offset Value from [0, 1) indicating the offset from the page at position.
 * @param offsetPixels Value in pixels indicating the offset from position.
 */
protected void onPageScrolled(int position, float offset, int offsetPixels) {
    // Offset any decor views if needed - keep them on-screen at all times.
    if (mDecorChildCount > 0) {
        final int scrollX = getScrollX();
        int paddingLeft = getPaddingLeft();
        int paddingRight = getPaddingRight();
        final int width = getWidth();
        final int childCount = getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = getChildAt(i);
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            if (!lp.isDecor) {
                continue;
            }

            final int hgrav = lp.gravity & Gravity.HORIZONTAL_GRAVITY_MASK;
            int childLeft = 0;
            switch (hgrav) {
            default:
                childLeft = paddingLeft;
                break;
            case Gravity.LEFT:
                childLeft = paddingLeft;
                paddingLeft += child.getWidth();
                break;
            case Gravity.CENTER_HORIZONTAL:
                childLeft = Math.max((width - child.getMeasuredWidth()) / 2, paddingLeft);
                break;
            case Gravity.RIGHT:
                childLeft = width - paddingRight - child.getMeasuredWidth();
                paddingRight += child.getMeasuredWidth();
                break;
            }
            childLeft += scrollX;

            final int childOffset = childLeft - child.getLeft();
            if (childOffset != 0) {
                child.offsetLeftAndRight(childOffset);
            }
        }
    }

    if (mOnPageChangeListener != null) {
        mOnPageChangeListener.onPageScrolled(position, offset, offsetPixels);
    }
    if (mInternalPageChangeListener != null) {
        mInternalPageChangeListener.onPageScrolled(position, offset, offsetPixels);
    }

    if (mPageTransformer != null) {
        final int scrollX = getScrollX();
        final int childCount = getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = getChildAt(i);
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();

            if (lp.isDecor) {
                continue;
            }

            final float transformPos = (float) (child.getLeft() - scrollX) / getWidth();
            mPageTransformer.transformPage(child, transformPos);
        }
    }

    mCalledSuper = true;
}

From source file:com.android.internal.widget.ViewPager.java

/**
 * This method will be invoked when the current page is scrolled, either as part
 * of a programmatically initiated smooth scroll or a user initiated touch scroll.
 * If you override this method you must call through to the superclass implementation
 * (e.g. super.onPageScrolled(position, offset, offsetPixels)) before onPageScrolled
 * returns./*from w  ww  .ja  va 2  s .  co m*/
 *
 * @param position Position index of the first page currently being displayed.
 *                 Page position+1 will be visible if positionOffset is nonzero.
 * @param offset Value from [0, 1) indicating the offset from the page at position.
 * @param offsetPixels Value in pixels indicating the offset from position.
 */
protected void onPageScrolled(int position, float offset, int offsetPixels) {
    // Offset any decor views if needed - keep them on-screen at all times.
    if (mDecorChildCount > 0) {
        final int scrollX = getScrollX();
        int paddingLeft = getPaddingLeft();
        int paddingRight = getPaddingRight();
        final int width = getWidth();
        final int childCount = getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = getChildAt(i);
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            if (!lp.isDecor)
                continue;

            final int hgrav = lp.gravity & Gravity.HORIZONTAL_GRAVITY_MASK;
            int childLeft = 0;
            switch (hgrav) {
            default:
                childLeft = paddingLeft;
                break;
            case Gravity.LEFT:
                childLeft = paddingLeft;
                paddingLeft += child.getWidth();
                break;
            case Gravity.CENTER_HORIZONTAL:
                childLeft = Math.max((width - child.getMeasuredWidth()) / 2, paddingLeft);
                break;
            case Gravity.RIGHT:
                childLeft = width - paddingRight - child.getMeasuredWidth();
                paddingRight += child.getMeasuredWidth();
                break;
            }
            childLeft += scrollX;

            final int childOffset = childLeft - child.getLeft();
            if (childOffset != 0) {
                child.offsetLeftAndRight(childOffset);
            }
        }
    }

    if (mOnPageChangeListener != null) {
        mOnPageChangeListener.onPageScrolled(position, offset, offsetPixels);
    }
    if (mInternalPageChangeListener != null) {
        mInternalPageChangeListener.onPageScrolled(position, offset, offsetPixels);
    }

    if (mPageTransformer != null) {
        final int scrollX = getScrollX();
        final int childCount = getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = getChildAt(i);
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();

            if (lp.isDecor)
                continue;

            final float transformPos = (float) (child.getLeft() - scrollX) / getPaddedWidth();
            mPageTransformer.transformPage(child, transformPos);
        }
    }

    mCalledSuper = true;
}

From source file:com.mobilesolutionworks.android.imagepaging.ImageViewPager.java

/**
 * This method will be invoked when the current page is scrolled, either as part
 * of a programmatically initiated smooth scroll or a user initiated touch scroll.
 * If you override this method you must call through to the superclass implementation
 * (e.g. super.onPageScrolled(position, offset, offsetPixels)) before onPageScrolled
 * returns./*from ww  w.ja  v a 2 s  .  c  om*/
 *
 * @param position     Position index of the first page currently being displayed.
 *                     Page position+1 will be visible if positionOffset is nonzero.
 * @param offset       Value from [0, 1) indicating the offset from the page at position.
 * @param offsetPixels Value in pixels indicating the offset from position.
 */
@SuppressLint("RtlHardcoded")
protected void onPageScrolled(int position, float offset, int offsetPixels) {
    // Offset any decor views if needed - keep them on-screen at all times.
    if (mDecorChildCount > 0) {
        final int scrollX = getScrollX();
        int paddingLeft = getPaddingLeft();
        int paddingRight = getPaddingRight();
        final int width = getWidth();
        final int childCount = getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = getChildAt(i);
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            if (!lp.isDecor)
                continue;

            final int hgrav = lp.gravity & Gravity.HORIZONTAL_GRAVITY_MASK;
            int childLeft = 0;
            switch (hgrav) {
            default:
                childLeft = paddingLeft;
                break;
            case Gravity.LEFT:
                childLeft = paddingLeft;
                paddingLeft += child.getWidth();
                break;
            case Gravity.CENTER_HORIZONTAL:
                childLeft = Math.max((width - child.getMeasuredWidth()) / 2, paddingLeft);
                break;
            case Gravity.RIGHT:
                childLeft = width - paddingRight - child.getMeasuredWidth();
                paddingRight += child.getMeasuredWidth();
                break;
            }
            childLeft += scrollX;

            final int childOffset = childLeft - child.getLeft();
            if (childOffset != 0) {
                child.offsetLeftAndRight(childOffset);
            }
        }
    }

    if (mOnPageChangeListener != null) {
        mOnPageChangeListener.onPageScrolled(position, offset, offsetPixels);
    }
    if (mInternalPageChangeListener != null) {
        mInternalPageChangeListener.onPageScrolled(position, offset, offsetPixels);
    }

    if (mPageTransformer != null) {
        final int scrollX = getScrollX();
        final int childCount = getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = getChildAt(i);
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();

            if (lp.isDecor)
                continue;

            final float transformPos = (float) (child.getLeft() - scrollX) / getClientWidth();
            mPageTransformer.transformPage(child, transformPos);
        }
    }

    mCalledSuper = true;
}

Example usage for android.view Gravity CENTER_HORIZONTAL

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