Develop Reference

Creating a Widget only application in Android?

To clarify the question:
I have seen multiple Apps in the Playstore that are widget only Apps without visible activities.
I tried to create one myself but I need to define a launcher Activity. Once I use the configuration Activity of the Widget as a launcher the app becomes visible in the app overview in Android.
https://i.imgur.com/lhx0TDG.png
If I dont define a launcher Activity I cant even deploy the app on the emulator.
The developerguide on https://developer.android.com/guide/topics/appwidgets/index.html about Widgets isnt really clear about how to handle this case.
Any help or directions where to find information is appreciated.

If you want to create a widget only android application without any activity. You don't have to declare any intents for your activity. Just pass the intent filter for android.appwidget.action.APPWIDGET_CONFIGURE It will make the activity load when the user adds it to their home screen. Now you can simply declare your configuration class with your widget layout xml file with android:configure attribute liking to the class file the widget runs on.
Hope this helps.

Android : how to show other apps widget in my activity

I am devlopeing a lock screen , which is just an activity in this i want to show widgets of other applications installed , i got the list of widgets . i can show these widgets in my activity layout. But the widgets are not working they are just dumb images of widgets. what should i do to make them work?
please reply if anyone knows anything about it.
thankyou

i have completed this task :)
you can use the tutorials at
http://www.anddev.org/appwidgethost_tutorial-t10329.html

How to find the code related to a small UI component quickly in a large Android codebase?

I just started my work as an Android developer. My first assignment is to fix several bugs of an App call DailyFinance.
One bug is UI related, if you click a button on a certain page, a dialog will pop up, but the dialog is not displayed properly. My question is how can I locate the code (xml layout file as well as activities) related to the dialog quickly in the codebase which I am not familiar with?

Couple approaches come in mind:
Search for any text that displayed on the target dialog.
Search button text and locate the xml layout file that that contains the button which launch the target dialog
Once find the xml layout file, determine the button 'id' as xxxxx, then you can further search for source contains references to 'R.id.xxxxx'

Set breakpoints on methods in files that implement the dialog. So maybe search for dialog and then put breakpoints inside the dialog. See it it gets hit when your dialog gets pulled up. Or just see where the layouts are set in files that have the word dialog in them. look for R.layout.someLayoutName.
One other suggestion is for some difficult layouts where its tough to see whats going on you can use the HierachyViewer to see the runtime view layouts: http://developer.android.com/tools/help/hierarchy-viewer.html Its worth running on your app to see the structure of the layouts at runtime which is often hard to see these relationships in the layout files before they have been inflated.
BTW, I was a student of CS and the biggest mistake I ever made was not to learn the debugger inside and out. Its without a doubt the most powerful ally you have to learn as well as fix bugs. If you think about it, code really is only an abstraction until you see it running inside the debugger.

android: How can I implement first time tutorial like Go Launcher in my app?

Go Launcher have a nice first-time tutorial. it is very similar to Stock ICS first time run. I want to learn how to make the similar tutorial display at the first launch of my app. How can I implement this Transparent view (which interacts with screen objects) in my android app?

I was trying to do something similar using a transparent activity with a viewpager inside it. I wanted static 'tutorial' images that users could swipe through.
One of the answers to my question mentioned an interesting library (called ShowcaseView). It seems like it may be a good fit for your requirements as well.
https://github.com/Espiandev/ShowcaseView

You can either use a FrameLayout or RelativeLayout as root of your Activity/Fragment, and put your "first time" View upon content with a (almost) transparent background, or use another Activity/Fragment themed with a transluscent window. (like this)
I'd rather use an Activity/Fragment, but this is up to you!

I wrote little library That contains a simple component for making ​​a app tour. It`s very restricted to my case but maybe could be your case . Single LessonCardView Showed onstartactivity for the first time or on button click Any criticism ,help or advice will be appreciated. thanks https://github.com/dnocode/DnoLib

You can implement a first-time user guide with the Spotlight library by TakuSemba.
It is similar to the one shared above and it is still well-maintained (as of 2021).
https://github.com/TakuSemba/Spotlight

show spinner before adding widget android

For a widget I am creating for the Android OS, I want the user to first select a certain option from a Spinner. Just like when you add a shortcut to the homescreen.
Is that possible or do you have to start an Activity?
If it is possible, can anyone explain how to do it?

Spinner widgets do not exist on their own -- you have to have them in an Activity. Android's app widget framework supports the notion of a configuration activity that is automatically launched when somebody chooses your widget. Just put your Spinner in there.