android.view.View#getLayoutParams ( )源码实例Demo

/**
 * Find the highest displayed edge of the section. If there is no member found then return the
 * default edge instead.
 *
 * @param sectionFirstPosition Section id, position of first item in the section.
 * @param firstIndex           Child index to start looking from.
 * @param defaultEdge          Default value.
 * @return Top (attached) edge of the section.
 */
public int getHighestEdge(int sectionFirstPosition, int firstIndex, int defaultEdge) {
    // Look from start to find children that are the highest.
    for (int i = firstIndex; i < mLayoutManager.getChildCount(); i++) {
        View child = mLayoutManager.getChildAt(i);
        LayoutManager.LayoutParams params = (LayoutManager.LayoutParams) child
                .getLayoutParams();
        if (params.getTestedFirstPosition() != sectionFirstPosition) {
            break;
        }
        if (params.isHeader) {
            continue;
        }
        // A more interesting layout would have to do something more here.
        return mLayoutManager.getDecoratedTop(child);
    }
    return defaultEdge;
}
 

public void setPanelHeight(int height) {
    panelHeight = height;
    if (isFullSize && botButtons != null && botButtons.rows.size() != 0) {
        buttonHeight = !isFullSize ? 42 : (int) Math.max(42, (panelHeight - AndroidUtilities.dp(30) - (botButtons.rows.size() - 1) * AndroidUtilities.dp(10)) / botButtons.rows.size() / AndroidUtilities.density);
        int count = container.getChildCount();
        int newHeight = AndroidUtilities.dp(buttonHeight);
        for (int a = 0; a < count; a++) {
            View v = container.getChildAt(a);
            LinearLayout.LayoutParams layoutParams = (LinearLayout.LayoutParams) v.getLayoutParams();
            if (layoutParams.height != newHeight) {
                layoutParams.height = newHeight;
                v.setLayoutParams(layoutParams);
            }
        }
    }
}
 

/**
 * Close the specified drawer view by animating it into view.
 *
 * @param drawerView Drawer view to close
 */
public void closeDrawer(View drawerView) {
    if (!isDrawerView(drawerView)) {
        throw new IllegalArgumentException("View " + drawerView + " is not a sliding drawer");
    }

    if (mFirstLayout) {
        final LayoutParams lp = (LayoutParams) drawerView.getLayoutParams();
        lp.onScreen = 0.f;
        lp.knownOpen = false;
    } else {
        if (checkDrawerViewAbsoluteGravity(drawerView, Gravity.LEFT)) {
            mLeftDragger.smoothSlideViewTo(drawerView, -drawerView.getWidth(),
                    drawerView.getTop());
        } else {
            mRightDragger.smoothSlideViewTo(drawerView, getWidth(), drawerView.getTop());
        }
    }
    invalidate();
}
 

/**
 * wrap a view
 * @param view the view to be wrapped
 * @return the original wrapper or create a new wrapper to wrap the view and replace its place into parent
 */
public static SmartSwipeWrapper wrap(View view) {
    SmartSwipeWrapper wrapper = peekWrapperFor(view);
    if (wrapper != null) {
        return wrapper;
    }
    ViewGroup.LayoutParams layoutParams = view.getLayoutParams();
    if (view.getParent() != null) {
        ViewGroup viewParent = (ViewGroup) view.getParent();
        wrapper = createNewWrapper(view.getContext());
        int index = viewParent.indexOfChild(view);
        viewParent.removeView(view);
        viewParent.addView(wrapper, index, layoutParams);
    } else {
        wrapper = createNewWrapper(view.getContext());
        if (layoutParams != null) {
            wrapper.setLayoutParams(layoutParams);
        }
    }
    wrapper.setContentView(view);
    return wrapper;
}
 

private void drawVertical(Canvas c, RecyclerView parent)
{
    final int left = parent.getPaddingLeft();
    final int right = parent.getWidth() - parent.getPaddingRight();

    final int childCount = parent.getChildCount();
    for (int i = 0; i < childCount; i++)
    {
        final View child = parent.getChildAt(i);
        final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
        final int top = child.getBottom() + params.bottomMargin;
        final int bottom = top + mDividerSize;
        if (mDividerDrawable != null)
        {
            mDividerDrawable.setBounds(left, top, right, bottom);
            mDividerDrawable.draw(c);
        } else if (mDividerPaint != null)
        {
            c.drawRect(left, top, right, bottom, mDividerPaint);
        }
    }
}
 

private void inflate(Context context, View root, String text, Drawable drawable, int res,
                     int tv_id, int iv_id, int verb) {
    if (!TextUtils.isEmpty(text)) {
        TextView tv = (TextView) root.findViewById(tv_id);
        if (tv != null) {
            tv.setText(text);
            tv.setVisibility(VISIBLE);
        }
    } else if (drawable != null) {
        ImageView iv = (ImageView) root.findViewById(iv_id);
        if (iv != null) {
            iv.setImageDrawable(drawable);
            iv.setVisibility(VISIBLE);
        }
    } else if (res != -1) {
        View view = LayoutInflater.from(context).inflate(res, this, false);
        addView(view);
        LayoutParams lp = (LayoutParams) view.getLayoutParams();
        lp.addRule(verb);
        lp.height = ViewGroup.LayoutParams.MATCH_PARENT;
        lp.width = ViewGroup.LayoutParams.WRAP_CONTENT;
        view.setLayoutParams(lp);
    }
}
 

/**
 * 设置视图的宽高
 *
 * @param view
 * @param width
 * @param height
 */
public void setViewWidthAndHeight(View view, int width, int height) {
    if (view == null) {
        return;
    }
    ViewGroup.LayoutParams lp = view.getLayoutParams();
    lp.width = width;
    lp.height = height;
    view.setLayoutParams(lp);
}
 

private void removeNonDecorViews() {
    for (int i = 0; i < getChildCount(); i++) {
        final View child = getChildAt(i);
        final LayoutParams lp = (LayoutParams) child.getLayoutParams();
        if (!lp.isDecor) {
            removeViewAt(i);
            i--;
        }
    }
}
 

@Override
public void measureChildWithMargins(View child, int widthUsed, int heightUsed) {
    RecyclerView.ViewHolder holder = listView.findContainingViewHolder(child);
    int pos = holder.getAdapterPosition();
    if (pos == getItemCount() - 1) {
        RecyclerView.LayoutParams layoutParams = (RecyclerView.LayoutParams) child.getLayoutParams();
        layoutParams.height = Math.max(lastItemHeight, 0);
    }
    super.measureChildWithMargins(child, 0, 0);
}
 

/** 增加View的高度以及paddingTop,增加的值为状态栏高度.一般是在沉浸式全屏给ToolBar用的 */
public static void setHeightAndPadding(Context context, View view) {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
        ViewGroup.LayoutParams lp = view.getLayoutParams();
        lp.height += getStatusBarHeight(context);//增高
        view.setPadding(view.getPaddingLeft(), view.getPaddingTop() + getStatusBarHeight(context),
                view.getPaddingRight(), view.getPaddingBottom());
    }
}
 

@Override
public void addView(View child, int index) {
    RecyclerView.LayoutParams lp = (RecyclerView.LayoutParams) child.getLayoutParams();
    if (showOneItemOnly) {
        if (canScrollHorizontally()) {
            lp.width = getWidth();
            if (lp.height != -2) {
                lp.height = getHeight();
            }
        } else {
            lp.height = getHeight();
            if (lp.width != -2) {
                lp.width = getWidth();
            }
        }
    } else {
        if (lp instanceof LayoutParams) {
            lp.width = ((LayoutParams) lp).origWidth;
            lp.height = ((LayoutParams) lp).origHeight;
        } else if (lp instanceof ScalableGridLayoutManager.LayoutParams) {
            lp.width = ((ScalableGridLayoutManager.LayoutParams) lp).getOrigWidth();
            lp.height = ((ScalableGridLayoutManager.LayoutParams) lp).getOrigHeight();
        }

    }
    super.addView(child, index);
}
 

/**
 * 获取某个childView在竖直方向所占的空间,将margin考虑进去
 *
 * @param view
 * @return
 */
public int getDecoratedMeasurementVertical(View view) {
    final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams)
            view.getLayoutParams();
    return getDecoratedMeasuredHeight(view) + params.topMargin
            + params.bottomMargin;
}
 

private void measureScrapChild(RecyclerView.Recycler recycler, int position, int widthSpec, int heightSpec, int[] measuredDimension) {
    View view = recycler.getViewForPosition(position);
    if (view != null) {
        RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) view.getLayoutParams();
        int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec,
                getPaddingTop() + getPaddingBottom(), p.height);
        view.measure(widthSpec, childHeightSpec);
        measuredDimension[0] = view.getMeasuredWidth() + p.leftMargin + p.rightMargin;
        measuredDimension[1] = view.getMeasuredHeight() + p.bottomMargin + p.topMargin;
        recycler.recycleView(view);
    }
}
 

public static void setMarginTopAndBottom(View view, int marginTop, int marginBottom) {
    WeakReference<View> viewWeakReference = new WeakReference<>(view);
    if (viewWeakReference.get() != null) {
        ViewGroup.MarginLayoutParams params = (ViewGroup.MarginLayoutParams) view.getLayoutParams();
        if (params != null) {
            params.topMargin = marginTop;
            params.bottomMargin = marginBottom;
            viewWeakReference.get().setLayoutParams(params);
        }
    }
}
 

public void setFrameLayoutChildInsets(View child, Rect newInsets, Rect oldInsets) {
    final LayoutParams lp = (LayoutParams) child.getLayoutParams();

    if (child instanceof Insettable) {
        ((Insettable) child).setInsets(newInsets);
    } else if (!lp.ignoreInsets) {
        lp.topMargin += (newInsets.top - oldInsets.top);
        lp.leftMargin += (newInsets.left - oldInsets.left);
        lp.rightMargin += (newInsets.right - oldInsets.right);
        lp.bottomMargin += (newInsets.bottom - oldInsets.bottom);
    }
    child.setLayoutParams(lp);
}
 

@Override
protected boolean onCustomMeasure(View view, int width, int height) {
    if (view == videoView.getControlsView()) {
        ViewGroup.LayoutParams layoutParams = view.getLayoutParams();
        layoutParams.width = videoView.getMeasuredWidth();
        layoutParams.height = videoView.getAspectRatioView().getMeasuredHeight() + (videoView.isInFullscreen() ? 0 : AndroidUtilities.dp(10));
    }
    return false;
}
 

private int getAbsoluteGravity(View menu) {
    final int gravity = ((LayoutParams) menu.getLayoutParams()).gravity;
    return GravityCompat.getAbsoluteGravity(gravity, ViewCompat.getLayoutDirection(this));
}
 

private void setWeight(int id, float progress) {
    View before = findViewById(id);
    LinearLayout.LayoutParams layoutParams = (LinearLayout.LayoutParams) before.getLayoutParams();
    layoutParams.weight = progress;
    before.requestLayout();
}
 

@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
    if (mVerticalDividerDrawableHeight <= 0 && mHorizontalDividerDrawableHeight <= 0) return;

    RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) view.getLayoutParams();
    int position = params.getViewAdapterPosition();
    int headersCount;
    int footerCount;
    int itemViewCount;
    FamiliarRecyclerView curFamiliarRecyclerView = null;
    if (parent instanceof FamiliarRecyclerView) {
        curFamiliarRecyclerView = (FamiliarRecyclerView) parent;

        footerCount = curFamiliarRecyclerView.getFooterViewsCount();
        headersCount = curFamiliarRecyclerView.getHeaderViewsCount();
        itemViewCount = curFamiliarRecyclerView.getAdapter().getItemCount() - headersCount - footerCount;
    } else {
        headersCount = 0;
        footerCount = 0;
        itemViewCount = parent.getAdapter().getItemCount();
    }

    // intercept filter
    if (isInterceptFilter(position, headersCount, footerCount, itemViewCount)) return;

    // set headView or footerView
    if (isHeadViewPos(headersCount, position)) {
        // head
        if (mOrientation == OrientationHelper.HORIZONTAL) {
            outRect.set(mVerticalDividerDrawableHeight, 0, 0, 0);
        } else {
            outRect.set(0, mHorizontalDividerDrawableHeight, 0, 0);
        }
        return;
    } else if (isFooterViewPos(headersCount, footerCount, itemViewCount, position)) {
        // footer
        if (mOrientation == OrientationHelper.HORIZONTAL) {
            outRect.set(mVerticalDividerDrawableHeight, 0, 0, 0);
        } else {
            outRect.set(0, mHorizontalDividerDrawableHeight, 0, 0);
        }
        return;
    } else if (isEmptyView(curFamiliarRecyclerView, position, headersCount)) {
        // emptyView
        if (isHeaderDividersEnabled && headersCount > 0) {
            if (mOrientation == OrientationHelper.HORIZONTAL) {
                outRect.set(mVerticalDividerDrawableHeight, 0, 0, 0);
            } else {
                outRect.set(0, mHorizontalDividerDrawableHeight, 0, 0);
            }
        }
        return;
    }

    // set itemView
    if (mLayoutManagerType == FamiliarRecyclerView.LAYOUT_MANAGER_TYPE_GRID || mLayoutManagerType == FamiliarRecyclerView.LAYOUT_MANAGER_TYPE_STAGGERED_GRID) {
        processGridOffsets(outRect, position, headersCount, view);
    } else {
        int topOrLeftSize;
        if ((!isHeaderDividersEnabled || headersCount == 0) && position - headersCount == 0) {
            topOrLeftSize = 0;
        } else {
            topOrLeftSize = mOrientation == OrientationHelper.VERTICAL ? mHorizontalDividerDrawableHeight : mVerticalDividerDrawableHeight;
        }

        if (mOrientation == OrientationHelper.HORIZONTAL) {
            outRect.set(topOrLeftSize, mItemViewBothSidesMargin, 0, mItemViewBothSidesMargin);
        } else {
            outRect.set(mItemViewBothSidesMargin, topOrLeftSize, mItemViewBothSidesMargin, 0);
        }
    }
}
 

/**
 * 测试tabflowlayout竖直状态
 * @param widthMeasureSpec
 * @param heightMeasureSpec
 */
private void measureTabVertical(int widthMeasureSpec, int heightMeasureSpec) {
    int widthMode = MeasureSpec.getMode(widthMeasureSpec);
    int widthSize = MeasureSpec.getSize(widthMeasureSpec);
    int heightMode = MeasureSpec.getMode(heightMeasureSpec);
    int heightSize = MeasureSpec.getSize(heightMeasureSpec);

    int childCount = getChildCount();
    int width = 0;
    int height = 0;

    for (int i = 0; i < childCount; i++) {
        View child = getChildAt(i);
        if (child.getVisibility() == GONE) {
            continue;
        }
        measureChild(child, widthMeasureSpec, heightMeasureSpec);
        MarginLayoutParams params = (MarginLayoutParams) child.getLayoutParams();
        //拿到 子控件宽高 + margin
        int cw = child.getMeasuredWidth() + params.leftMargin + params.rightMargin;
        int ch = child.getMeasuredHeight() + params.topMargin + params.bottomMargin;

        height += ch;

        width = Math.max(width, cw);
    }

    if (MeasureSpec.EXACTLY == widthMode ) {
        width = widthSize;
    } else {
        width += getPaddingLeft() + getPaddingRight();
    }
    if (MeasureSpec.EXACTLY == heightMode) {
        height = heightSize;
    } else {
        height += getPaddingTop() + getPaddingBottom();
    }

    mViewHeight = height;
    setMeasuredDimension(width, height);
}