7 接着又是一堆逻辑和赋值，并在某种情况下还调用了host.measure()。算是measure 完成了

8. 然后是layout 的部分。

        final boolean didLayout = mLayoutRequested && !mStopped;
        boolean triggerGlobalLayoutListener = didLayout
                || attachInfo.mRecomputeGlobalAttributes;
        if (didLayout) {
            mLayoutRequested = false;
            host.layout(0, 0, host.getMeasuredWidth(), host.getMeasuredHeight());

    public void layout(int l, int t, int r, int b) {
        int oldL = mLeft;
        int oldT = mTop;
        int oldB = mBottom;
        int oldR = mRight;
        boolean changed = setFrame(l, t, r, b);
        if (changed || (mPrivateFlags & LAYOUT_REQUIRED) == LAYOUT_REQUIRED) {
            if (ViewDebug.TRACE_HIERARCHY) {
                ViewDebug.trace(this, ViewDebug.HierarchyTraceType.ON_LAYOUT);
            }

            onLayout(changed, l, t, r, b);
            mPrivateFlags &= ~LAYOUT_REQUIRED;

            if (mOnLayoutChangeListeners != null) {
                ArrayList
  
    listenersCopy =
                        (ArrayList
   
    ) mOnLayoutChangeListeners.clone(); int numListeners = listenersCopy.size(); for (int i = 0; i < numListeners; ++i) { listenersCopy.get(i).onLayoutChange(this, l, t, r, b, oldL, oldT, oldR, oldB); } } } mPrivateFlags &= ~FORCE_LAYOUT; }
   
  

在setFrame()中，判断新的位置和旧的位置是否一致。

    protected boolean setFrame(int left, int top, int right, int bottom) {
        boolean changed = false;

        if (DBG) {
            Log.d("View", this + " View.setFrame(" + left + "," + top + ","
                    + right + "," + bottom + ")");
        }

        if (mLeft != left || mRight != right || mTop != top || mBottom != bottom) {
            changed = true;

            // Remember our drawn bit
            int drawn = mPrivateFlags & DRAWN;

            int oldWidth = mRight - mLeft;
            int oldHeight = mBottom - mTop;
            int newWidth = right - left;
            int newHeight = bottom - top;
            boolean sizeChanged = (newWidth != oldWidth) || (newHeight != oldHeight);

            // Invalidate our old position
            invalidate(sizeChanged);

            mLeft = left;
            mTop = top;
            mRight = right;
            mBottom = bottom;

            mPrivateFlags |= HAS_BOUNDS;


            if (sizeChanged) {
                if ((mPrivateFlags & PIVOT_EXPLICITLY_SET) == 0) {
                    // A change in dimension means an auto-centered pivot point changes, too
                    if (mTransformationInfo != null) {
                        mTransformationInfo.mMatrixDirty = true;
                    }
                }
                onSizeChanged(newWidth, newHeight, oldWidth, oldHeight);
            }

            if ((mViewFlags & VISIBILITY_MASK) == VISIBLE) {
                // If we are visible, force the DRAWN bit to on so that
                // this invalidate will go through (at least to our parent).
                // This is because someone may have invalidated this view
                // before this call to setFrame came in, thereby clearing
                // the DRAWN bit.
                mPrivateFlags |= DRAWN;
                invalidate(sizeChanged);
                // parent display list may need to be recreated based on a change in the bounds
                // of any child
                invalidateParentCaches();
            }

            // Reset drawn bit to original value (invalidate turns it off)
            mPrivateFlags |= drawn;

            mBackgroundSizeChanged = true;
        }
        return changed;
    }

? ? void invalidate(boolean invalidateCache) {
		if (p != null && ai != null) {
                final Rect r = ai.mTmpInvalRect;
                r.set(0, 0, mRight - mLeft, mBottom - mTop);
                // Don't call invalidate -- we don't want to internally scroll
                // our own bounds
                p.invalidateChild(this, r);
            }
        }