I have an android application which is running on production for several years. Lately, I have discovered a problem with a ListView in the app, that gets blurry while scrolling. The problem only occurs under Android Marshmallow.
Here is a screenshot of the ListView while scrolling
Any help would be much appreciated.
Thanks!
Preface: I posted a separate answer prior to this one, but that solution only worked on my MotoX. I later discovered it did not work for my Galaxy Tab A. The answer here seems to be more universal:
I was able to fix my scrolling blur by defining a separate ListView style for my application and specifying a different list divider. So, for my application theme I set this:
<item name="android:listViewStyle">#style/ListViewStyleNoBlur</item>
Where ListViewStyleNoBlur is defined as:
<style name="ListViewStyleNoBlur" parent="#android:style/Widget.ListView.White">
<item name="android:divider">#android:drawable/divider_horizontal_bright</item>
</style>
I specified these in a values-v23 resources folder so the change doesn't affect pre-Marshmallow devices.
My application theme is based off of android:style/Theme.Light, which is why my list view style's parent is android:style/Widget.ListView.White. My app min SDK is 8, which is why I'm using such an "old" theme. I also noticed that if I use a "newer" theme, such as Holo, the blur does not exist.
I also had this problem and, through trial-and-error, finally found a solution. Hopefully it will also work for you. This appears to be a bug in Marshmallow related to the scroll bar in list views. I had the following property set in my application theme, and removing this property fixed the blurry scrolling:
<item name="android:fadeScrollbars">false</item>
Using true instead of false also works, but is unnecessary since it is the default. I also discovered (through trail-and-error) that using android:fastScrollEnabled="true" causes the same blurring, but based on your scrollbar style, you do not appear to be using it.
In summary, don't use android:fadeScrollbars. If that doesn't fix your issue, try playing around with any other scrollbar-related styles you may be using on your ListView, bearing in mind these styles may be part of the view directly, or part of an activity or application theme.
Related
I'm transitioning an app from Holo style to Material design, and am stuck with a ProgressBar widget that won't show up as it is supposed to.
It's supposed to be flat like (and that's what AndroidStudio's preview gives me):
But when on the emulator (running Android 7.1.1), I only get the version with an arrow tip (also, it's not being animated)
I've already tried removing every single bit of customization on top of the base AppTheme, which inherits from Material:
<style name="AppTheme" parent="android:Theme.Material.Light"></style>
The ProgressBar is declared without any styling whatsoever, plain:
<ProgressBar
android:id="#+id/sign_in_activity_login_progressbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:indeterminate="true" />
I'm at a loss here, already removed everything on the project that could reference styling, but this still happens. Already cleaned/rebuilt the project many times. What am I missing? How can I make that progress bar look like the flat one?
This is the problem of the emulator. Sometimes emulator does not give us the proper result.
If you run it on a device then you will get to see the difference and it also depends on a device. If any device's OS is customized then the progress bar may look different.
At the moment, I'm stuck with a very annoying kind of "bug" I assume regarding all Pre-Lollipop Android versions. It appears that (support) fragments don't apply the activity's theme they're assigned to. To make my explanations a bit easier, have the following demonstration:
My app runs with a turquoise theme at first. Let's say, the user decided to change the turquoise theme to a red theme. He or she restarts the app and is greeted with the following:
(screenshot taken on an Android 4.4.2 tablet)
Terrible sight, isn't it? However, if I run the same app in an emulator with Android L the whole theme problem doesn't even seem to exist.
There's especially one thing which seems odd about the tablet screenshot. The fragment itself doesn't apply the theme but child components inside the fragment which get added lateron (like the view with the exclamation mark which is hosted by a ViewPager) take and apply the theme as if nothing happened.
I'm not quite sure what the issue might be. I've done everything as stated in every document available. I set the theme before I call setContentView(resource) in the corresponding activity. I tried to do the trick with ContextThemeWrapper but it was no use.
Relevant code:
The activity's onCreate()
The fragment's onCreateView()
The fragment's layout
Attributes
Themes (a lot of them)
I tried to resolve this issue for days now and I still can't find out why this is not working. I haven't found a suitable answer yet and would love some advise.
I've been the victim to my own stupidity. I had another close look on my project setup and found this:
My tablet takes its layout resources from the sw600dp-folder, but I forgot to change the corresponding layout to take attributes instead of hardcoded colors. I think I have to retire after making such a stupid mistake.
There are lots of way to style ListViews to give them elegant look, but all of them involve modyfying the adapter or writing additional code.
With the release of Android 4.0, unfortunetely things have to change. Google polished their Holo theme and gave it new look. All of the developers are now encouraged to use it, in order to make all apps look the same.
And here's the problem. Google rolled out 4.0, but there are still people using older Android versions. We can't just leave our previous custom application themes and use Holo, because it will ruin visual experience for users with older devices. And we can't force 4.0 users just to use Holo, because let's be honest - it's still not perfect.
The goal is to use builtin themes system and prepare some alternatives for Holo, which will look great on all devices. Then we can just switch between Holo and our themes with just setTheme() and no additional problems. Unfortunetely it's not that simple. We are limited to the capabilities of existing theme system and some things are just hard to do. And here comes my question.
Taking everything I've mentioned into consideration, how can we control ListView look? I'm not able to figure out, how to:
create list with rounded corners and make sure the selector background doesn't ruin it when selecting first/last element
create rounded corners not for the list but sections separated by headers, something like here:
The solution should affect ListViews created by PreferenceActivity without any additional lines of code. Everything should be contained in the theme:
<theme name="SampleTheme" parent="android:Theme">
...
</theme>
I kindly ask not to post solutions that do not use styles & themes. They can be easily found in another questions, here on Stack Overflow.
Thanks in advance.
I can see two ways to solve this.
One is simply to use a theme for your listviews specifying the background, which in turn is a 9 patch with rounded corners or an xml shape you specify (with rounded corners as well). This will have the side-effect of the listview row selector appearing 'over' the background you specified, therefore kind of spoiling the effect. It is quite straightforward to implement though.
The second option is to simply always add headers and footers to your listviews, which have backgrounds that are selectors with rounded corners on top (and bottom). You can specify styles for these as well if you really want to.
Sorry for this last comment, but I had to say it. Please don't try to make your app look like an iPhone app :)
I recently updated my app, changing it's design a bit. Amongst other things, I styled buttons with custom drawables (well - not exactly custom, just taken from ICS release). Everything works well, except for one of the users.
Instead of:
He sees:
This is a Button, but I have also other controls styled with the same background drawable and the problems appears there (so, it's not limited to buttons).
There are two changed style properties that these controls have in common. One is, of course, a background drawable. The other is textAppearance:
<item name="android:textAppearance">?android:attr/textAppearanceMediumInverse</item>
I came to a conclusion, that this user is using some strange theme, which alters the default value of textAppearance* styles. But I have no idea what attribute may control this "text background color" (android:background does not work, checked this just in case). Or maybe I'm looking in the wrong place and this problem is not related to textAppearance?
EDIT:
The background image is a semi-transparent PNG file.
Android version 2.3.7, Motorola Milestone. That's all I got.
EDIT 2, Fixed:
OK, the problem was at the users side, it turned out he was using CyanogenMod7 with forced 16bit trasparency. After switching that option off, everything works.
OK, the problem was at the users side, it turned out he was using CyanogenMod7 with forced 16bit trasparency. After switching that option off, everything works.
In the new official Twitter app, the scrollbars in all the ListViews the app uses are hidden unless the user is scrolling through the list.
When you start scrolling, the scrollbars appear. When you stop, they fade out with an animation until they are gone completely.
I can't seem to find anything in the documentation that indicates this as being a standard feature.
Is this something included in the API? If not, anyone know how this might be done?
Confirmed : either use android:fadeScrollbars ( if you're API level 5 )
or try to use setOnScrollListener to check scroll status and hide/show the bars . Some code examples are in this thread:
how to detect Android ListView Scrolling stopped?
You can enable scroll bar fading for your entire app on API level 5 and newer via a custom theme and the fadeScrollbars style attribute by adding this to styles.xml:
<style name="Theme.App" parent="android:Theme.Light">
<item name="android:fadeScrollbars">true</item>
</style>
Then set the new theme for your application in AndroidManifest.xml:
<application android:icon="#drawable/app_icon"
android:label="#string/app_name"
android:description="#string/description"
android:theme="#style/Theme.App">
Just be sure you're not overriding this global theme on individual activities. Earlier Android versions will safely ignore this unknown XML attribute and not fade the scrollbars.
I haven't used them yet, but you might play around with android:scrollbarDefaultDelayBeforeFade and android:scrollbarFadeDuration, available on all widgets (i.e., subclasses of View).
I followed Alex's answer and it worked using both the theme settings and through code.
GridView gridview = (GridView) findViewById(R.id.mygridView);
gridview.setScrollbarFadingEnabled(false);
I did encounter a problem however with the Gallery Component. Whilst the following will compile fine, it will throw a NullPointerException. I assume this is to do with a Gallery not having scrollbars to show/hide.
Gallery gallery = (Gallery) findViewById(R.id.myGallery);
gallery.setScrollbarFadingEnabled(false); // <-- this will throw an exception
Android 2.2