Mobile Development Collective

4374 votes

132 answers

1.9m views

How can I close/hide the Android soft keyboard programmatically?

I have an EditText and a Button in my layout. After writing in the edit field and clicking on the Button, I want to hide the virtual keyboard when touching outside the keyboard. Can someone provide a ...

Community wiki

31 revs, 19 users 19%
Vidar Vestnes

3566 votes

78 answers

1.2m views

Why is the Android emulator so slow? How can we speed up the Android emulator?

I have got a 2.67 GHz Celeron processor, and 1.21 GB of RAM on a x86 Windows XP Professional machine. My understanding is that the Android Emulator should start fairly quickly on such a machine, but ...

Community wiki

18 revs, 13 users 37%
Peter Mortensen

6423 votes

35 answers

1.5m views

What is the difference between px, dip, dp, and sp?

What is the difference between the units of measure px, dip, dp, and sp?

capecrawler

68.3k

asked Jan 8, 2010 at 3:23

3181 votes

54 answers

836k views

How to stop EditText from gaining focus when an activity starts in Android?

I have an Activity in Android, with two elements: EditText ListView When my Activity starts, the EditText immediately has the input focus (flashing cursor). I don't want any control to have input ...

Mark

39.9k

asked Oct 12, 2009 at 15:03

2746 votes

66 answers

1.5m views

How can I fix 'android.os.NetworkOnMainThreadException'?

I got an error while running my Android project for RssReader. Code: URL url = new URL(urlToRssFeed); SAXParserFactory factory = SAXParserFactory.newInstance(); SAXParser parser = factory....

bejoy george

29.9k

asked Jun 14, 2011 at 12:02

2336 votes

75 answers

1.6m views

How do I center text horizontally and vertically in a TextView?

How do I center the text horizontally and vertically in a TextView, so that it appears exactly in the middle of the TextView in Android?

Pablo Fernandez

288k

asked Jan 11, 2009 at 0:27

3115 votes

54 answers

1.3m views

Is there a unique Android device ID?

Do Android devices have a unique ID, and if so, what is a simple way to access it using Java?

Tyler

31.7k

asked May 7, 2010 at 0:47

1799 votes

99 answers

658k views

How can I make a UITextField move up when the keyboard is present - on starting to edit?

With the iOS SDK: I have a UIView with UITextFields that bring up a keyboard. I need it to be able to: Allow scrolling of the contents of the UIScrollView to see the other text fields once the ...

Community wiki

25 revs, 15 users 42%
philfreo

2350 votes

51 answers

773k views

Vertically align text to top within a UILabel

I have a UILabel with space for two lines of text. Sometimes, when the text is too short, this text is displayed in the vertical center of the label. How do I vertically align the text to always be ...

Stefan

29k

asked Jun 28, 2009 at 8:54

1132 votes

108 answers

906k views

R cannot be resolved - Android error

I just downloaded and installed the new Android SDK. I wanted to create a simple application to test drive it. The wizard created this code: package eu.mauriziopz.gps; import android.app.Activity; ...

Community wiki

9 revs, 6 users 58%
Maurizio Pozzobon

1334 votes

82 answers

1.0m views

Xcode - How to fix 'NSUnknownKeyException', Reason: "… this class is not key value coding-compliant for the key X" error?

I'm trying to link a UILabel with an IBOutlet created in my class. My application is crashing with the following error" *** Terminating app due to uncaught exception 'NSUnknownKeyException', ...

Community wiki

26 revs, 16 users 36%
Guillaume Dubois

2877 votes

35 answers

915k views

How can I save an activity state using the save instance state?

I've been working on the Android SDK platform, and it is a little unclear how to save an application's state. So given this minor re-tooling of the 'Hello, Android' example: package com.android.hello; ...

Bernard

45.6k

asked Sep 30, 2008 at 4:41

1975 votes

44 answers

1.2m views

How to get screen dimensions as pixels in Android

I created some custom elements, and I want to programmatically place them to the upper right corner (n pixels from the top edge and m pixels from the right edge). Therefore I need to get the screen ...

Niko Gamulin

66.6k

asked Jun 19, 2009 at 8:25

2093 votes

41 answers

580k views

How to lazy load images in ListView in Android

I am using a ListView to display some images and captions associated with those images. I am getting the images from the Internet. Is there a way to lazy load images so while the text displays, the UI ...

lostInTransit

71.1k

asked Feb 12, 2009 at 15:59

1259 votes

69 answers

1.2m views

You need to use a Theme.AppCompat theme (or descendant) with this activity

Android Studio 0.4.5 Android documentation for creating custom dialog boxes: http://developer.android.com/guide/topics/ui/dialogs.html If you want a custom dialog, you can instead display an ...

ant2009

22.8k

asked Feb 16, 2014 at 17:34

1541 votes

53 answers

1.3m views

How do I pass data between Activities in Android application?

I have a scenario where, after logging in through a login page, there will be a sign-out button on each activity. On clicking sign-out, I will be passing the session id of the signed in user to sign-...

UMAR-MOBITSOLUTIONS

78.1k

asked Jan 19, 2010 at 6:06

799 votes

105 answers

1.2m views

"cannot resolve symbol R" in Android Studio

In every instance in all of my classes where I reference R.id.something, the R is in red and it says "cannot resolve symbol R". Also every time there is R.layout.something it is underlined in red and ...

ez4nick

10.2k

asked Jun 11, 2013 at 21:18

1759 votes

40 answers

1.6m views

Android 8: Cleartext HTTP traffic not permitted

I had reports from users with Android 8 that my app (that uses back-end feed) does not show content. After investigation I found following Exception happening on Android 8: 08-29 12:03:11.246 11285-...

david.s

17.8k

asked Aug 29, 2017 at 13:48

1611 votes

39 answers

952k views

How can you get the build/version number of your Android application?

I need to figure out how to get or make a build number for my Android application. I need the build number to display in the UI. Do I have to do something with AndroidManifest.xml?

Fahad Ali Shaikh

16.1k

asked Jan 6, 2011 at 14:43

1640 votes

45 answers

1.3m views

How can I open a URL in Android's web browser from my application?

How to open a URL from code in the built-in web browser rather than within my application? I tried this: try { Intent myIntent = new Intent(Intent.ACTION_VIEW, Uri.parse(download_link)); ...

Arutha

26.6k

asked Feb 4, 2010 at 17:51

1244 votes

55 answers

648k views

How do I "select Android SDK" in Android Studio?

After a successful import of an Eclipse-Android-Project into "Android Studio 1.4", I get the error "Please select Android SDK" when I click on the button to run the application in ...

delete

19.3k

asked Dec 18, 2015 at 10:16

2272 votes

32 answers

828k views

What is 'Context' on Android?

In Android programming, what exactly is a Context class and what is it used for? I read about it on the developer site, but I am unable to understand it clearly.

Brigadier

23.5k

asked Aug 26, 2010 at 6:12

1097 votes

61 answers

677k views

How to change Status Bar text color in iOS

My application has a dark background, but in iOS 7 the status bar became transparent. So I can't see anything there, only the green battery indicator in the corner. How can I change the status bar ...

Oleksandr Veremchuk

11.1k

asked Jul 16, 2013 at 14:11

1504 votes

44 answers

528k views

Passing data between view controllers

I'm new to iOS and Objective-C and the whole MVC paradigm and I'm stuck with the following: I have a view that acts as a data entry form and I want to give the user the option to select multiple ...

Matt Price

34.6k

asked Mar 6, 2011 at 12:43

1308 votes

50 answers

709k views

Activity has leaked window that was originally added

What is this error, and why does it happen? 05-17 18:24:57.069: ERROR/WindowManager(18850): Activity com.mypkg.myP has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@44c46ff0 ...

Pentium10

208k

asked May 17, 2010 at 15:51

951 votes

69 answers

893k views

Xcode building for iOS Simulator, but linking in an object file built for iOS, for architecture 'arm64'

I am trying to get a large (and working on Xcode 11!) project building in Xcode 12 (beta 5) to prepare for iOS 14. The codebase was previously in Objective-C, but now it contains both Objective-C and ...

btxios

9,625

asked Aug 26, 2020 at 23:40

1393 votes

44 answers

653k views

Strange OutOfMemory issue while loading an image to a Bitmap object

I have a ListView with a couple of image buttons on each row. When the user clicks the list row, it launches a new activity. I have had to build my own tabs because of an issue with the camera layout. ...

Community wiki

24 revs, 17 users 20%
Chrispix

1303 votes

44 answers

1.8m views

How to get current time and date in Android

How can I get the current time and date in an Android app?

M7M

13.1k

asked Mar 20, 2011 at 16:12

925 votes

71 answers

491k views

"Conversion to Dalvik format failed with error 1" on external JAR

In my Android application in Eclipse, I get the following error. UNEXPECTED TOP-LEVEL EXCEPTION: java.lang.IllegalArgumentException: already added: Lorg/xmlpull/v1/XmlPullParser; .... Conversion to ...

Community wiki

9 revs, 5 users 46%
Michel

4050 votes

12 answers

375k views

Proper use cases for Android UserManager.isUserAGoat()?

I was looking at the new APIs introduced in Android 4.2. While looking at the UserManager class I came across the following method: public boolean isUserAGoat() Used to determine whether the ...

Ovidiu Latcu

72.3k

asked Nov 14, 2012 at 8:34

1279 votes

42 answers

546k views

How can I disable the UITableView selection?

When you tap a row in a UITableView, the row is highlighted and selected. Is it possible to disable this so tapping a row does nothing?

davidmytton

39.3k

asked Oct 10, 2008 at 11:32

738 votes

78 answers

333k views

Why is there extra padding at the top of my UITableView with style UITableViewStyleGrouped in iOS7

Starting in iOS7, there is additional space at the top of my UITableView's which have a style UITableViewStyleGrouped. Here is an example: The tableview starts at the first arrow, there are 35 pixels ...

esilver

28.5k

asked Sep 18, 2013 at 19:07

1953 votes

28 answers

540k views

What's the difference between the atomic and nonatomic attributes?

What do atomic and nonatomic mean in property declarations? @property(nonatomic, retain) UITextField *userName; @property(atomic, retain) UITextField *userName; @property(retain) UITextField *...

Alex Wayne

188k

asked Feb 26, 2009 at 2:31

1611 votes

30 answers

984k views

Transport security has blocked a cleartext HTTP

What setting do I need to put in my info.plist to enable HTTP mode as per the following error message? Transport security has blocked a cleartext HTTP (http://) resource load since it is insecure. ...

Jeef

27.3k

asked Jul 6, 2015 at 20:10

1322 votes

42 answers

742k views

Run/install/debug Android applications over Wi-Fi?

I thought there was a way to test your applications in development over Wi-Fi. Is this possible? I'd love to be able to untether my phone and develop wirelessly.

Naftuli Kay

92.1k

asked Feb 4, 2011 at 2:23

1414 votes

39 answers

519k views

How can I check for an active Internet connection on iOS or macOS?

I would like to check to see if I have an Internet connection on iOS using the Cocoa Touch libraries or on macOS using the Cocoa libraries. I came up with a way to do this using an NSURL. The way I ...

Brock Woolf

47.4k

asked Jul 5, 2009 at 8:45

1128 votes

46 answers

849k views

How to add dividers and spaces between items in RecyclerView

This is an example of how it could have been done previously in the ListView class, using the divider and dividerHeight parameters: <ListView android:id="@+id/activity_home_list_view" ...

EyesClear

28.4k

asked Jul 7, 2014 at 20:01

577 votes

98 answers

536k views

Error type 3 Error: Activity class {} does not exist

I have an IntelliJ Android project, that I successfully imported to Android Studio 0.4.0. It works perfectly if I don't change anything in manifest. However, when I want to change the launcher ...

Jacob

15.3k

asked Jan 4, 2014 at 0:35

1244 votes

45 answers

451k views

Android SDK installation doesn't find JDK

I'm trying to install the Android SDK on my Windows 7 x64 System. jdk-6u23-windows-x64.exe is installed, but the Android SDK setup refuses to proceed because it doesn't find the JDK installation. ...

Community wiki

11 revs, 11 users 44%
Simon

1618 votes

29 answers

713k views

Using Auto Layout in UITableView for dynamic cell layouts & variable row heights

How do you use Auto Layout within UITableViewCells in a table view to let each cell's content and subviews determine the row height (itself/automatically), while maintaining smooth scrolling ...

smileyborg

30.5k

asked Sep 11, 2013 at 16:48

1164 votes

40 answers

704k views

How to make links in a TextView clickable

I have the following TextView defined: <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/txtCredits" ...

Richard

28.9k

asked Apr 29, 2010 at 1:41

1251 votes

40 answers

300k views

Is quitting an application frowned upon?

Moving on in my attempt to learn Android, I just read the following: Question: Does the user have a choice to kill the application unless we put a menu option in to kill it? If no such option ...

Community wiki

7 revs, 6 users 67%
Ted

1214 votes

38 answers

1.8m views

How do I display an alert dialog on Android?

I want to display a dialog/popup window with a message to the user that shows "Are you sure you want to delete this entry?" with one button that says 'Delete'. When Delete is touched, it should delete ...

Community wiki

10 revs, 8 users 37%
UMAR-MOBITSOLUTIONS

570 votes

91 answers

833k views

Getting error "No such module" using Xcode, but the framework is there

I'm currently coding in Swift, and I've got an error: No such module Social But I don't understand, because the module is in my project, declared in "Linked frameworks and Libraries" and in "...

alexandresecanove

6,185

asked Apr 7, 2015 at 19:59

1271 votes

43 answers

1.1m views

How can I develop for iPhone using a Windows development machine?

Is there any way to tinker with the iPhone SDK on a Windows machine? Are there plans for an iPhone SDK version for Windows? The only other way I can think of doing this is to run a Mac VM image on a ...

Community wiki

6 revs, 6 users 36%
ryan

2083 votes

23 answers

779k views

Is there a way to run Python on Android?

We are working on an S60 version and this platform has a nice Python API.. However, there is nothing official about Python on Android, but since Jython exists, is there a way to let the snake and the ...

Bite code

598k

asked Sep 19, 2008 at 13:21

1463 votes

34 answers

410k views

Activity restart on rotation Android

In my Android application, when I rotate the device (slide out the keyboard) then my Activity is restarted (onCreate is called). Now, this is probably how it's supposed to be, but I do a lot of ...

Isaac Waller

32.8k

asked Jan 19, 2009 at 0:28

728 votes

64 answers

522k views

How to check internet access on Android? InetAddress never times out

I got a AsyncTask that is supposed to check the network access to a host name. But the doInBackground() is never timed out. Anyone have a clue? public class HostAvailabilityTask extends AsyncTask<...

Vidar Vestnes

43k

asked Oct 13, 2009 at 14:59

1195 votes

37 answers

795k views

findViewById in Fragment

I am trying to create an ImageView in a Fragment which will refer to the ImageView element which I have created in the XML for the Fragment. However, the findViewById method only works if I extend an ...