Popupwindow 適配25版本與簡單跟蹤

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N_MR1) {
   int dropLocation = UIUtils.dip2Px(1) + viewHeight+
         screenLocation[1];
   mPopupWindow.showAtLocation(this, Gravity.NO_GRAVITY, 0, dropLocation);
} else {
   mPopupWindow.showAsDropDown(this, 0, UIUtils.dip2Px(1));

}

注意這個不應該 在 

onWindowFocusChanged  獲取以下的信息 因爲在25 也會獲取不到

@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
   super.onLayout(changed, l, t, r, b);

   if(!isFirst){
      isFirst=true;
      getLocationOnScreen(screenLocation);
      viewHeight=getMeasuredHeight();
   }

   if(changed){
      isFirst=false;
   }
}

  1是一條分割線 ,screenLocation是這個視圖位置相對於屏幕的左上角 x,y ,viewHeight 就是視圖的高

效果:

爲什麼

showAsDropDown 方法就不行呢

在斷點調試的時候發現 在23和25findDropDownPosition(....)  方法是不一樣的.

23.版本

private boolean findDropDownPosition(View anchor, WindowManager.LayoutParams p, int xoff,
            int yoff, int gravity) {
        final int anchorHeight = anchor.getHeight();
        final int anchorWidth = anchor.getWidth();
        if (mOverlapAnchor) {
            yoff -= anchorHeight;
        }

        anchor.getLocationInWindow(mDrawingLocation);
        p.x = mDrawingLocation[0] + xoff;
        p.y = mDrawingLocation[1] + anchorHeight + yoff;

        final int hgrav = Gravity.getAbsoluteGravity(gravity, anchor.getLayoutDirection())
                & Gravity.HORIZONTAL_GRAVITY_MASK;
        if (hgrav == Gravity.RIGHT) {
            // Flip the location to align the right sides of the popup and
            // anchor instead of left.
            p.x -= mPopupWidth - anchorWidth;
        }

        boolean onTop = false;

        p.gravity = Gravity.LEFT | Gravity.TOP;

        anchor.getLocationOnScreen(mScreenLocation);
        final Rect displayFrame = new Rect();
        anchor.getWindowVisibleDisplayFrame(displayFrame);

        final int screenY = mScreenLocation[1] + anchorHeight + yoff;
        final View root = anchor.getRootView();
        if (screenY + mPopupHeight > displayFrame.bottom
                || p.x + mPopupWidth - root.getWidth() > 0) {
            // If the drop down disappears at the bottom of the screen, we try
            // to scroll a parent scrollview or move the drop down back up on
            // top of the edit box.
            if (mAllowScrollingAnchorParent) {
                final int scrollX = anchor.getScrollX();
                final int scrollY = anchor.getScrollY();
                final Rect r = new Rect(scrollX, scrollY, scrollX + mPopupWidth + xoff,
                        scrollY + mPopupHeight + anchorHeight + yoff);
                anchor.requestRectangleOnScreen(r, true);
            }

            // Now we re-evaluate the space available, and decide from that
            // whether the pop-up will go above or below the anchor.
            anchor.getLocationInWindow(mDrawingLocation);
            p.x = mDrawingLocation[0] + xoff;
            p.y = mDrawingLocation[1] + anchorHeight + yoff;

            // Preserve the gravity adjustment.
            if (hgrav == Gravity.RIGHT) {
                p.x -= mPopupWidth - anchorWidth;
            }

            // Determine whether there is more space above or below the anchor.
            anchor.getLocationOnScreen(mScreenLocation);
            onTop = (displayFrame.bottom - mScreenLocation[1] - anchorHeight - yoff) <
                    (mScreenLocation[1] - yoff - displayFrame.top);
            if (onTop) {
                p.gravity = Gravity.LEFT | Gravity.BOTTOM;
                p.y = root.getHeight() - mDrawingLocation[1] + yoff;
            } else {
                p.y = mDrawingLocation[1] + anchorHeight + yoff;
            }
        }

        if (mClipToScreen) {
            final int displayFrameWidth = displayFrame.right - displayFrame.left;
            final int right = p.x + p.width;
            if (right > displayFrameWidth) {
                p.x -= right - displayFrameWidth;
            }

            if (p.x < displayFrame.left) {
                p.x = displayFrame.left;
                p.width = Math.min(p.width, displayFrameWidth);
            }

            if (onTop) {
                final int popupTop = mScreenLocation[1] + yoff - mPopupHeight;
                if (popupTop < 0) {
                    p.y += popupTop;
                }
            } else {
                p.y = Math.max(p.y, displayFrame.top);
            }
        }

        p.gravity |= Gravity.DISPLAY_CLIP_VERTICAL;

        return onTop;
    }

25. 版本

private boolean findDropDownPosition(View anchor, WindowManager.LayoutParams outParams,
            int xOffset, int yOffset, int width, int height, int gravity) {
        final int anchorHeight = anchor.getHeight();
        final int anchorWidth = anchor.getWidth();
        if (mOverlapAnchor) {
            yOffset -= anchorHeight;
        }

        // Initially, align to the bottom-left corner of the anchor plus offsets.
        final int[] drawingLocation = mTmpDrawingLocation;
        anchor.getLocationInWindow(drawingLocation);
        outParams.x = drawingLocation[0] + xOffset;
        outParams.y = drawingLocation[1] + anchorHeight + yOffset;

        final Rect displayFrame = new Rect();
        anchor.getWindowVisibleDisplayFrame(displayFrame);
        if (width == MATCH_PARENT) {
            width = displayFrame.right - displayFrame.left;
        }
        if (height == MATCH_PARENT) {
            height = displayFrame.bottom - displayFrame.top;
        }

        // Let the window manager know to align the top to y.
        outParams.gravity = computeGravity();
        outParams.width = width;
        outParams.height = height;

        // If we need to adjust for gravity RIGHT, align to the bottom-right
        // corner of the anchor (still accounting for offsets).
        final int hgrav = Gravity.getAbsoluteGravity(gravity, anchor.getLayoutDirection())
                & Gravity.HORIZONTAL_GRAVITY_MASK;
        if (hgrav == Gravity.RIGHT) {
            outParams.x -= width - anchorWidth;
        }

        final int[] screenLocation = mTmpScreenLocation;
        anchor.getLocationOnScreen(screenLocation);

        // First, attempt to fit the popup vertically without resizing.
        final boolean fitsVertical = tryFitVertical(outParams, yOffset, height,
                anchorHeight, drawingLocation[1], screenLocation[1], displayFrame.top,
                displayFrame.bottom, false);

        // Next, attempt to fit the popup horizontally without resizing.
        final boolean fitsHorizontal = tryFitHorizontal(outParams, xOffset, width,
                anchorWidth, drawingLocation[0], screenLocation[0], displayFrame.left,
                displayFrame.right, false);

        // If the popup still doesn't fit, attempt to scroll the parent.
        if (!fitsVertical || !fitsHorizontal) {
            final int scrollX = anchor.getScrollX();
            final int scrollY = anchor.getScrollY();
            final Rect r = new Rect(scrollX, scrollY, scrollX + width + xOffset,
                    scrollY + height + anchorHeight + yOffset);
            if (mAllowScrollingAnchorParent && anchor.requestRectangleOnScreen(r, true)) {
                // Reset for the new anchor position.
                anchor.getLocationInWindow(drawingLocation);
                outParams.x = drawingLocation[0] + xOffset;
                outParams.y = drawingLocation[1] + anchorHeight + yOffset;

                // Preserve the gravity adjustment.
                if (hgrav == Gravity.RIGHT) {
                    outParams.x -= width - anchorWidth;
                }
            }

            // Try to fit the popup again and allowing resizing.
            tryFitVertical(outParams, yOffset, height, anchorHeight, drawingLocation[1],
                    screenLocation[1], displayFrame.top, displayFrame.bottom, mClipToScreen);
            tryFitHorizontal(outParams, xOffset, width, anchorWidth, drawingLocation[0],
                    screenLocation[0], displayFrame.left, displayFrame.right, mClipToScreen);
        }

        // Return whether the popup's top edge is above the anchor's top edge.
        return outParams.y < drawingLocation[1];
    }

 這個兩個版本的方法都是通過outParams.y=screenLocation[1]+anchorHeight+yOffset 來確定其Popup...的位置.所以我也使用了這個方式.

25.版本的 findDropDownPosition(....)裏面的tryFitVertical(...)方法使用outParam.y發生了改變

所以25 版本不管用.  網上說的是什麼手機問題,不過是sdk 的更新而已.