Expose onScrollStarted/onScrollStopped listeners in verticalScroll modifier [169509805]

Fixed

Bug

Status Update

No update yet.

Description

ya...@gmail.com

created issue #1

Sep 28, 2020 02:45PM

Component used: ScrollableColumn/verticalScroll modifier

Version used: alpha-03

Devices/Android versions reproduced on: Irrelevant

The scrollable modifier has onScrollStarted/onScrollStopped parameters, but the verticalScroll/horizontalScroll modifiers are not exposing those. Some type visibility like state.scrollableController make it impossible to use scrollable manually.

Would also be nice to have those on ScrollableColumn/ScrollableRow I guess.

Use case: I'd like to receive the event where the user stopped scrolling, and use the velocity to trigger a snap behavior.

I have the following page:

Stack {
    val collapsingToolbarExpandedSize = ...
    ScrollableColumn(){
       Spacer(modifier = Modifier.height(collapsingToolbarSize))
    }
    CollapsingToolbar {
          ....
    }
}

I want to be able to trigger a smooth scroll to a certain value (0 or collapsingToolbarSize) to snap the toolbar state.

Maybe there is a different way of doing this. I tried using the rawDragGestureFilter, but the onStop was always receiving a value of 0 for the offset. Maybe this is a bug?

Thanks.

Comments

so...@google.com <so...@google.com> Sep 28, 2020 03:46PM

Assigned to ma...@google.com.

ma...@google.com <ma...@google.com> #2Sep 28, 2020 05:14PM

Hi,

I also see my text cut off when I set maxLines = 2. Is it the same issue?

  Box(
    modifier =
      Modifier.size(
        width = 108dp,
        height = 34dp,
      ),
    contentAlignment = Alignment.Center,
  ) {
    BasicText(
      text = "text text text",
      maxLines = 2,
      autoSize = AutoSize.StepBased(minFontSize = 1.sp, maxFontSize = 13.sp, stepSize = 0.2.sp),
    )
  }

ya...@gmail.com <ya...@gmail.com> #3Sep 28, 2020 09:06PM

Project: platform/frameworks/support
Branch: androidx-main
Author: Jossi Wolf <jossiwolf@google.com>
Link: https://android-review.googlesource.com/3450389

Fix TextAutoSize bug with maxLines = 1

Expand for full commit details

Fix TextAutoSize bug with maxLines = 1 
 
We were overcaching the paragraphIntrinsics in MultiParagraphLayoutCache when mutating the style. For `AutoSizeStepBased` instances with biased windows (more values smaller/bigger than the optimal), this could result in performing layout with outdated intrinsics, and thus an outdated style and font size, without surfacing this in the TextLayoutResult. 
 
Test: New MultiParagraphLayoutCacheTests and manual testing 
Relnote: Fixed a bug in BasicText with TextAutoSize and maxLines set to 1. 
Fixes: 376834366 
 
Change-Id: Ic0450c763c5d764492995b44ee1fe570246a9689

Files:

M compose/foundation/foundation/src/androidInstrumentedTest/kotlin/androidx/compose/foundation/text/modifiers/MultiParagraphLayoutCacheTest.kt
M compose/foundation/foundation/src/commonMain/kotlin/androidx/compose/foundation/text/modifiers/MultiParagraphLayoutCache.kt

Hash: e1b712d78cc60384ed67a56c006148291ba146a6
Date: Tue Jan 07 18:52:26 2025

ap...@google.com <ap...@google.com> #4Oct 13, 2020 04:16PM

Marked as fixed.

#2, yeah, that's the same issue.

ma...@google.com <ma...@google.com> #5Oct 19, 2020 01:27PM

Thanks @jo...@google.com for fixing this! Do you know when the fix would be available for g3 apps?

Issue 169509805