I need to add a drop down to my app, which is running on the AppCompat theme, since we are not using the Material design components, but rather have our own design for buttons, etc.
For a simple feature, I need to use a dropdown and here I think the Exposed drop down from the Material design theme would work nicely.
However, if I'm not specifically using the MaterialComponents theme in my styles, the app will crash whenever I try to use the style on the TextInputLayout.
Is there a way of using the nice Exposed dropdown from MaterialComponents without using the entire theme (as this overrides all colors for buttons and such)? Or maybe just a simple way of getting a nice and simple dropdown otherwise. Spinners seem kinda hard to work with..
Cheers.
Related
We have an app using Android View system that we want to start migrating to Jetpack Compose soon.
The app has some screens that look pretty different so that it doesn't seem to work to use a single Material theme for the whole app. We can't really figure out which color will be primary, secondary and variants. We have more colors than this.
So I see two alternatives: Either don't use Material theme but make own own custom theme for the whole app, or use Material theme but have two or three different themes so each screen can use the relevant one.
It seems pretty easy to for solution 2 (several Material themes in a single app) in Compose. But I'm wondering if it's a good practice, if there are cons that we haven't thought about?
Thanks for your advices!
Compose library has limited set of available colors in Colors class. If you want to have additional colors there are two solutions I can think of:
Create extensions for Colors class for each specific color. This is fast but downside of this method is that you will have to handle logic with theming inside of each color added. Sample
Create custom Colors class yourself and provide it using CompositionLocal . This way you won't need to include theme checks everywhere, you can do it only once and provide required Colors instance with CompositionLocalProvider
Trying to add Dark Mode to my app. I am mostly there, most things work as I expect after I made the required changes, however I have a problem with the Toolbar. What have I missed?
Screenshot of Toolbar issue, and layout
You're applying AppTheme to popupTheme, what does it have?
You don't usually need to make a custom one, one of the pre-made ones like ThemeOverlay.MaterialComponents.Toolbar is enough.
And actually, if you're using MaterialComponents, you don't need to apply anything to your app to make it work in Dark Mode, just use the DayNight MaterialComponents theme.
I have a requirement to display a theme that comes from a webservice (return the color etc). What I want to know is can I create a style programmatically? I have my code setup to incorporate theme and I have 2 themes defined in xml which work perfectly fine. And now I want to add a third theme which is not locally in an xml. Is this even possible?
The other approach to achieve this is to create custom classes for views and apply the style according to the theme. Which is I don't want to do, as it is very tedious and error prone.
Any other suggestions are welcomed as well.
I was trying to change the android spinner popup window background by setting the android:popupBackground, but it didn't have any effect. Is there any way I can change it?
<Spinner
android:id="#+id/eventNameSpinner"
android:layout_width="160dp"
android:layout_height="30dp"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:layout_marginLeft="6dp"
android:background="#drawable/btn_name"
android:paddingBottom="2dp"
android:paddingTop="2dp"
android:popupBackground="#drawable/bkg">
I presume you are trying to change the "outer" backgroud of a Spinner's popup, not the background of Spinner "pupup items". Also, I presume that by popup, you mean a Spinner's dialog mode, where a floating dialog window appears on top of your activity, as opposed to the new dropdown mode.
Strategy
For a clean, sustainable approach which behaves well across multiple Android platforms and reduces the need for redundancy in the App, I believe it is essential to understand what the official docs don't tell us. So follow me on a short journey.
The tricky part about Spinners is that an Adapter is used to connect them to data. While it is relatively easy to identify the hooks for changing the appearance of android.R.layout.simple_spinner_item and its friends, those only determine the style of the Spinner's currently displayed item as well as each single popup item. But it is the Adapter which is responsible for creating the ListView and other widgets which frame that ListView.
This complexity is probably the reason why Android has introduced some attributes which can be specified on-the-fly "for" the Spinner although they are then applied to the Spnner's children, such as android:popupBackground. This is not necessarily a clean approach, rather a limited set of convenience functions. Regarding popupBackground, btw, this was introduced in API level 1, but Spinners respect it only in spinnerMode=dropdown, which was introduced in API level 11. That's the reason why you'll never be notified if you use it wrongly.
Older Android Versions (such as 2.2)
ListView
Knowing that the Adapter creates a ListView, it's not a bad idea to change the ListView appearance in one's theme, so there's one single place for the design change and the styling straightforward, like so:
<style name="MyTheme" parent="#android:style/[reference to original theme]" >
<item name="android:listViewStyle">#style/myListView</item>
[...]
</style>
<style name="myListView" parent="#android:style/Widget.ListView">
[check Android's Widget.ListView to understand what you can change here]
</style>
AlertDialog
Unfortunately, there's more work ahead. Because android:prompt can be used to create a headline for the popup, the popup really consists of more than just the ListView.
Android uses an AlertDialog
Recent Android Versions (such as 4.2)
Now that the AlertDialogs are styled, we still have to address the fact that more recent versions of Android don't use AlertDialogs for Spinner dialogs any more. That doesn't hurt, because for those, the AlertDialog style shouldd be kept anyways. It just means we need to style the new popup as well.
To do so, create version specific theme XML files to pull the additional styles into your customized theme, and provide version specific style XML files.
Feel like trying it yourself, starting here?
android:popupBackground is only valid when using android:spinnerMode = "dropdown" , thats probably why it wasnt any effect in your code. You need to tell that spinner which mode its in with some XML.
android:spinnerMode = "dropdown"
Links
http://developer.android.com/reference/android/widget/Spinner.html#attr_android:popupBackground
http://developer.android.com/reference/android/widget/Spinner.html
I am writing my little Android app. I pop up a dialog control which is a nice, non-fullscreen, rounded-corners dialog by setting android:theme="#android:style/Theme.Dialog" on the activity in my manifest. That all works just as I expected. However it is just a drab, grey-titled dialog as in this screenshot:
I've noticed however that a LOT of applications, when they pop up dialogs have a nice, blue-themed title as in this screen shot.
I would assume this theme is some common theme, as it shows up in a LOT of different apps. I would assume it is something built in to the OS. (My phone is a Captivate with the official Froyo release). Of course it COULD be something that every developer simply re-coded on their own, but I doubt that.
Assuming that this is a common theme, how do I utilize it in my app? What changes do I need to make to my activity to have it use that theme?
Thanks in advance!
You can set your activity to use a default theme like Theme.Black. There are default themes and they are in R.style - although i'm not sure which are available to which platforms(i.e. i think the holo themes are for 3.0 and up...
http://developer.android.com/reference/android/R.style.html
see here http://developer.android.com/guide/topics/ui/themes.html for defining your own custom themes and scroll all the way down for using the "platform styles" and themes.
Rather messy (there doesn't seem to be a good reference for this), but the platform styles are defined in \platforms\android-\data\res\values\styles.xml and \platforms\android-\data\res\values\themes.xml. You can dig through those and figure out the theme/style IDs that are available at compile time.
Other than that its really just trial and error.
To make a dialog you need to extend the dialog class. And to have a nice title bar you can use:
requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
and have your own custom title.
to have a title use:
setTitle("MyTitle");
You can also assign your custom view for the title.