MuPDF Android库垂直滚动 [英] MuPDF Android Library Vertical Scroll
本文介绍了MuPDF Android库垂直滚动的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我正在使用 MuPdf Android库， 垂直滚动，而不是水平页面滚动，尝试了所有但失败的方法，搜索了问题，并在 Stackoverflow ，有人回答了他的问题，该问题适用于问题作者，但我没有得到此解决方案，因此将这些方法放入ReaderView，但是通过这种方式，我发现了与其他活动有关的错误，请帮助我将这些方法放在哪里等.有人在 mupdf 垂直滚动中工作吗?
I am using MuPdf Android Library, I want vertical Scroll instead of horizontal page Scrolling, tried everything but failed, googled the problem and found an answer on Stackoverflow and someone answered his question which worked for the Questions Author but I am not getting this solution, putted these methods in ReaderView but by this way I found errors which were related to other activities, kindly help me to where put these methods etc. someone worked on mupdf vertical scrolling?
推荐答案
您可以通过将水平值更改为垂直值(将所有与宽度相关的计算更改为height)来完成.更改onLayout()& onFling()如下:(参考)
You can do by changing the horizontal values to vertical ( change all width related calculations to height ). Change onLayout() & onFling() as below: (Reference)
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
// "Edit mode" means when the View is being displayed in the Android GUI editor. (this class
// is instantiated in the IDE, so we need to be a bit careful what we do).
if (isInEditMode())
return;
View cv = mChildViews.get(mCurrent);
Point cvOffset;
if (!mResetLayout) {
// Move to next or previous if current is sufficiently off center
if (cv != null) {
cvOffset = subScreenSizeOffset(cv);
// cv.getRight() may be out of date with the current scale
// so add left to the measured width for the correct position
//if (cv.getLeft() + cv.getMeasuredWidth() + cvOffset.x + GAP/2 + mXScroll < getWidth()/2 && mCurrent + 1 < mAdapter.getCount()) {
if (cv.getTop() + cv.getMeasuredHeight() + cvOffset.y + GAP / 2 + mYScroll < getHeight() / 2 && mCurrent + 1 < mAdapter.getCount()) {
postUnsettle(cv);
// post to invoke test for end of animation
// where we must set hq area for the new current view
mStepper.prod();
onMoveOffChild(mCurrent);
mCurrent++;
onMoveToChild(mCurrent);
}
//if (cv.getLeft() - cvOffset.x - GAP/2 + mXScroll >= getWidth()/2 && mCurrent > 0) {
if (cv.getTop() - cvOffset.y - GAP / 2 + mYScroll >= getHeight() / 2 && mCurrent > 0) {
postUnsettle(cv);
// post to invoke test for end of animation
// where we must set hq area for the new current view
mStepper.prod();
onMoveOffChild(mCurrent);
mCurrent--;
onMoveToChild(mCurrent);
}
}
// Remove not needed children and hold them for reuse
int numChildren = mChildViews.size();
int childIndices[] = new int[numChildren];
for (int i = 0; i < numChildren; i++)
childIndices[i] = mChildViews.keyAt(i);
for (int i = 0; i < numChildren; i++) {
int ai = childIndices[i];
if (ai < mCurrent - 1 || ai > mCurrent + 1) {
View v = mChildViews.get(ai);
onNotInUse(v);
mViewCache.add(v);
removeViewInLayout(v);
mChildViews.remove(ai);
}
}
} else {
mResetLayout = false;
mXScroll = mYScroll = 0;
// Remove all children and hold them for reuse
int numChildren = mChildViews.size();
for (int i = 0; i < numChildren; i++) {
View v = mChildViews.valueAt(i);
onNotInUse(v);
mViewCache.add(v);
removeViewInLayout(v);
}
mChildViews.clear();
// Don't reuse cached views if the adapter has changed
if (mReflowChanged) {
mReflowChanged = false;
mViewCache.clear();
}
// post to ensure generation of hq area
mStepper.prod();
}
// Ensure current view is present
int cvLeft, cvRight, cvTop, cvBottom;
boolean notPresent = (mChildViews.get(mCurrent) == null);
cv = getOrCreateChild(mCurrent);
// When the view is sub-screen-size in either dimension we
// offset it to center within the screen area, and to keep
// the views spaced out
cvOffset = subScreenSizeOffset(cv);
if (notPresent) {
//Main item not already present. Just place it top left
cvLeft = cvOffset.x;
cvTop = cvOffset.y;
} else {
// Main item already present. Adjust by scroll offsets
cvLeft = cv.getLeft() + mXScroll;
cvTop = cv.getTop() + mYScroll;
}
// Scroll values have been accounted for
mXScroll = mYScroll = 0;
cvRight = cvLeft + cv.getMeasuredWidth();
cvBottom = cvTop + cv.getMeasuredHeight();
if (!mUserInteracting && mScroller.isFinished()) {
Point corr = getCorrection(getScrollBounds(cvLeft, cvTop, cvRight, cvBottom));
cvRight += corr.x;
cvLeft += corr.x;
cvTop += corr.y;
cvBottom += corr.y;
} else if (cv.getMeasuredWidth() <= getWidth()) {
// // When the current view is as small as the screen in height, clamp
// // it vertically
// Point corr = getCorrection(getScrollBounds(cvLeft, cvTop, cvRight, cvBottom));
// cvTop += corr.y;
// cvBottom += corr.y;
// When the current view is as small as the screen in width, clamp
// it horizontally
Point corr = getCorrection(getScrollBounds(cvLeft, cvTop, cvRight, cvBottom));
cvRight += corr.x;
cvLeft += corr.x;
}
cv.layout(cvLeft, cvTop, cvRight, cvBottom);
if (mCurrent > 0) {
View lv = getOrCreateChild(mCurrent - 1);
Point leftOffset = subScreenSizeOffset(lv);
/*int gap = leftOffset.x + GAP + cvOffset.x;
lv.layout(cvLeft - lv.getMeasuredWidth() - gap,
(cvBottom + cvTop - lv.getMeasuredHeight())/2,
cvLeft - gap,
(cvBottom + cvTop + lv.getMeasuredHeight())/2);*/
int gap = leftOffset.y + GAP + cvOffset.y;
lv.layout((cvRight + cvLeft - lv.getMeasuredWidth())/2,
cvTop - lv.getMeasuredHeight() - gap,
(cvRight + cvLeft + lv.getMeasuredWidth())/2,
cvTop - gap);
}
if (mCurrent + 1 < mAdapter.getCount()) {
View rv = getOrCreateChild(mCurrent + 1);
Point rightOffset = subScreenSizeOffset(rv);
/*int gap = cvOffset.x + GAP + rightOffset.x;
rv.layout(cvRight + gap,
(cvBottom + cvTop - rv.getMeasuredHeight())/2,
cvRight + rv.getMeasuredWidth() + gap,
(cvBottom + cvTop + rv.getMeasuredHeight())/2);*/
int gap = cvOffset.y + GAP + rightOffset.y;
rv.layout((cvRight + cvLeft - rv.getMeasuredWidth())/2,
cvBottom + gap,
(cvRight + cvLeft + rv.getMeasuredWidth())/2,
cvBottom + rv.getMeasuredHeight() + gap);
}
invalidate();
}
还添加以下几行:
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
if (mScaling)
return true;
View v = mChildViews.get(mCurrent);
if (v != null) {
Rect bounds = getScrollBounds(v);
switch (directionOfTravel(velocityX, velocityY)) {
case MOVING_UP:
if (bounds.top >= 0) {
// Fling off to the left bring next view onto screen
View vl = mChildViews.get(mCurrent + 1);
if (vl != null) {
slideViewOntoScreen(vl);
return true;
}
}
break;
case MOVING_DOWN:
if (bounds.bottom <= 0) {
// Fling off to the right bring previous view onto screen
View vr = mChildViews.get(mCurrent - 1);
if (vr != null) {
slideViewOntoScreen(vr);
return true;
}
}
break;
}
mScrollerLastX = mScrollerLastY = 0;
// If the page has been dragged out of bounds then we want to spring back
// nicely. fling jumps back into bounds instantly, so we don't want to use
// fling in that case. On the other hand, we don't want to forgo a fling
// just because of a slightly off-angle drag taking us out of bounds other
// than in the direction of the drag, so we test for out of bounds only
// in the direction of travel.
//
// Also don't fling if out of bounds in any direction by more than fling
// margin
Rect expandedBounds = new Rect(bounds);
expandedBounds.inset(-FLING_MARGIN, -FLING_MARGIN);
if (withinBoundsInDirectionOfTravel(bounds, velocityX, velocityY)
&& expandedBounds.contains(0, 0)) {
mScroller.fling(0, 0, (int) velocityX, (int) velocityY, bounds.left, bounds.right, bounds.top, bounds.bottom);
mStepper.prod();
}
}
return true;
}
这篇关于MuPDF Android库垂直滚动的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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