@Override
public void notifyAppearStateChange(
int firstVisible, int lastVisible, int directionX, int directionY) {
// notify appear state
Iterator<AppearanceHelper> it = mAppearComponents.values().iterator();
String direction = directionY > 0 ? "up" : "down";
if (getOrientation() == Constants.Orientation.HORIZONTAL) {
direction = directionX > 0 ? "left" : "right";
}
while (it.hasNext()) {
AppearanceHelper item = it.next();
WXComponent component = item.getAwareChild();
if (!item.isWatch()) {
continue;
}
boolean outOfVisibleRange =
item.getCellPositionINScollable() < firstVisible
|| item.getCellPositionINScollable() > lastVisible;
View view = component.getHostView();
if (view == null) {
continue;
}
boolean visible = (!outOfVisibleRange) && item.isViewVisible();
int result = item.setAppearStatus(visible);
if (WXEnvironment.isApkDebugable()) {
WXLogUtils.d("appear", "item " + item.getCellPositionINScollable() + " result " + result);
}
if (result == AppearanceHelper.RESULT_NO_CHANGE) {
continue;
}
component.notifyAppearStateChange(
result == AppearanceHelper.RESULT_APPEAR
? Constants.Event.APPEAR
: Constants.Event.DISAPPEAR,
direction);
}
}
