先看效果:
主要处理:
使用PullToRefreshScrollView修改内部的scrollView源码,更换成可以固定顶部的自定义scrollView
@Override protected ScrollView createRefreshableView(Context context, AttributeSet attrs) { ScrollView scrollView; if (VERSION.SDK_INT >= VERSION_CODES.GINGERBREAD) { //TODO 修改代码 添加滑动固定顶部标题sv scrollView = new InternalScrollViewSDK9(context, attrs);// scrollView = new FloatScrollView(context, attrs); } else { scrollView = new ScrollView(context, attrs); } scrollView.setId(R.id.scrollview); return scrollView; }下面是scrollview的代码:
public static final String FLOAT = "float"; private ArrayList<View> stickyViews; private View currentlyStickingView; private float stickyViewTopOffset; private int stickyViewLeftOffset; private boolean redirectTouchesToStickyView; private boolean clippingToPadding; private boolean clipToPaddingHasBeenSet; private final Runnable invalidateRunnable = new Runnable() { @Override public void run() { if (currentlyStickingView != null) { int l = getLeftForViewRelativeOnlyChild(currentlyStickingView); int t = getBottomForViewRelativeOnlyChild(currentlyStickingView); int r = getRightForViewRelativeOnlyChild(currentlyStickingView); int b = (int) (getScrollY() + (currentlyStickingView.getHeight() + stickyViewTopOffset)); invalidate(l, t, r, b); } postDelayed(this, 16); } }; public void setup() { stickyViews = new ArrayList<View>(); } private int getLeftForViewRelativeOnlyChild(View v) { int left = v.getLeft(); while (v.getParent() != getChildAt(0)) { v = (View) v.getParent(); left += v.getLeft(); } return left; } private int getTopForViewRelativeOnlyChild(View v) { int top = v.getTop(); while (v.getParent() != getChildAt(0)) { v = (View) v.getParent(); top += v.getTop(); } return top; } private int getRightForViewRelativeOnlyChild(View v) { int right = v.getRight(); while (v.getParent() != getChildAt(0)) { v = (View) v.getParent(); right += v.getRight(); } return right; } private int getBottomForViewRelativeOnlyChild(View v) { int bottom = v.getBottom(); while (v.getParent() != getChildAt(0)) { v = (View) v.getParent(); bottom += v.getBottom(); } return bottom; } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { super.onLayout(changed, l, t, r, b); if (!clipToPaddingHasBeenSet) { clippingToPadding = true; } notifyHierarchyChanged(); } @Override public void setClipToPadding(boolean clipToPadding) { super.setClipToPadding(clipToPadding); clippingToPadding = clipToPadding; clipToPaddingHasBeenSet = true; } @Override public void addView(View child) { super.addView(child); findStickyViews(child); } @Override public void addView(View child, int index) { super.addView(child, index); findStickyViews(child); } @Override public void addView(View child, int index, android.view.ViewGroup.LayoutParams params) { super.addView(child, index, params); findStickyViews(child); } @Override public void addView(View child, int width, int height) { super.addView(child, width, height); findStickyViews(child); } @Override public void addView(View child, android.view.ViewGroup.LayoutParams params) { super.addView(child, params); findStickyViews(child); } @Override protected void dispatchDraw(Canvas canvas) { super.dispatchDraw(canvas); if (currentlyStickingView != null) { canvas.save(); canvas.translate(getPaddingLeft() + stickyViewLeftOffset, getScrollY() + stickyViewTopOffset + (clippingToPadding ? getPaddingTop() : 0)); canvas.clipRect(0, (clippingToPadding ? -stickyViewTopOffset : 0), getWidth(), currentlyStickingView.getHeight()); currentlyStickingView.draw(canvas); canvas.restore(); } } @Override public boolean dispatchTouchEvent(MotionEvent ev) { if (ev.getAction() == MotionEvent.ACTION_DOWN) { redirectTouchesToStickyView = true; } if (redirectTouchesToStickyView) { redirectTouchesToStickyView = currentlyStickingView != null; if (redirectTouchesToStickyView) { redirectTouchesToStickyView = ev.getY() <= (currentlyStickingView.getHeight() + stickyViewTopOffset) && ev.getX() >= getLeftForViewRelativeOnlyChild(currentlyStickingView) && ev.getX() <= getRightForViewRelativeOnlyChild(currentlyStickingView); } } else if (currentlyStickingView == null) { redirectTouchesToStickyView = false; } if (redirectTouchesToStickyView) { topForViewRelativeOnlyChild = getTopForViewRelativeOnlyChild(currentlyStickingView); ev.offsetLocation(0, -1 * ((getScrollY() + stickyViewTopOffset) - topForViewRelativeOnlyChild)); } return super.dispatchTouchEvent(ev); } private boolean hasNotDoneActionDown = true; @Override public boolean onTouchEvent(MotionEvent ev) { if (redirectTouchesToStickyView) { ev.offsetLocation(0, ((getScrollY() + stickyViewTopOffset) - getTopForViewRelativeOnlyChild(currentlyStickingView))); } if (ev.getAction() == MotionEvent.ACTION_DOWN || ev.getAction() == MotionEvent.ACTION_MOVE) { hasNotDoneActionDown = false; } if (hasNotDoneActionDown) { MotionEvent down = MotionEvent.obtain(ev); down.setAction(MotionEvent.ACTION_DOWN); super.onTouchEvent(down); hasNotDoneActionDown = false; } if (ev.getAction() == MotionEvent.ACTION_UP || ev.getAction() == MotionEvent.ACTION_CANCEL) { hasNotDoneActionDown = true; } return super.onTouchEvent(ev); } @Override protected void onScrollChanged(int l, int t, int oldl, int oldt) { super.onScrollChanged(l, t, oldl, oldt); doTheStickyThing(); } private void doTheStickyThing() { View viewThatShouldStick = null; View approachingView = null; for (View v : stickyViews) { int viewTop = getTopForViewRelativeOnlyChild(v) - getScrollY() + (clippingToPadding ? 0 : getPaddingTop()); if (viewTop <= 0) { if (viewThatShouldStick == null || viewTop > (getTopForViewRelativeOnlyChild(viewThatShouldStick) - getScrollY() + (clippingToPadding ? 0 : getPaddingTop()))) { viewThatShouldStick = v; } } else { if (approachingView == null || viewTop < (getTopForViewRelativeOnlyChild(approachingView) - getScrollY() + (clippingToPadding ? 0 : getPaddingTop()))) { approachingView = v; } } } if (viewThatShouldStick != null) { stickyViewTopOffset = approachingView == null ? 0 : Math.min(0, getTopForViewRelativeOnlyChild(approachingView) - getScrollY() + (clippingToPadding ? 0 : getPaddingTop()) - viewThatShouldStick.getHeight()); if (viewThatShouldStick != currentlyStickingView) { if (currentlyStickingView != null) { stopStickingCurrentlyStickingView(); } stickyViewLeftOffset = getLeftForViewRelativeOnlyChild(viewThatShouldStick); startStickingView(viewThatShouldStick); } } else if (currentlyStickingView != null) { stopStickingCurrentlyStickingView(); } } private void startStickingView(View viewThatShouldStick) { currentlyStickingView = viewThatShouldStick; } private void stopStickingCurrentlyStickingView() { currentlyStickingView = null; removeCallbacks(invalidateRunnable); } private void notifyHierarchyChanged() { if (currentlyStickingView != null) { stopStickingCurrentlyStickingView(); } stickyViews.clear(); findStickyViews(getChildAt(0)); doTheStickyThing(); invalidate(); } private void findStickyViews(View v) { if (v instanceof ViewGroup) { ViewGroup vg = (ViewGroup) v; for (int i = 0; i < vg.getChildCount(); i++) { String tag = getStringTagForView(vg.getChildAt(i)); if (tag != null && tag.contains(FLOAT)) { stickyViews.add(vg.getChildAt(i)); } else if (vg.getChildAt(i) instanceof ViewGroup) { findStickyViews(vg.getChildAt(i)); } } } else { String tag = (String) v.getTag(); if (tag != null && tag.contains(FLOAT)) { stickyViews.add(v); } } } private String getStringTagForView(View v) { Object tagObject = v.getTag(); return String.valueOf(tagObject); } }
