Develop Reference

Problems implementing the new sensitive clipboard code in Android SDK 13

Has anyone else tried to mark their clipboard copied data as sensitive as per the following recommendation?
https://developer.android.com/about/versions/13/features/copy-paste
clipData.apply {
description.extras = PersistableBundle().apply {
putBoolean(ClipDescription.EXTRA_IS_SENSITIVE, true)
}
}
When I tried to do so, I don't find a clipData.apply method.
How can I set the sensitivity settings in an android app Java code?

apply() is a Kotlin scope function. You appear to be programming in Java, so the Kotlin syntax will not work for you.
By eyeball, the Java equivalent would be:
PersistableBundle extras = new PersistableBundle();
extras.putBoolean(ClipDescription.EXTRA_IS_SENSITIVE, true);
clipData.getDescription().setExtras(extras);

My device will flash back to the background after the multilingual handover jump

BaseActivity.java
Language switching
Intent
OnClickListener
Error demo
No error message was prompted.

You are using old style of language switching which were deprecated and removed after releasing android 8, It completely get removed. However, if you want to use your application for android prior to 26, you have to change your code on language switching Image as follow:
Configuration config = new Configuration(resources.getConfiguration());
New instance of Configuration have to be passed to resources.updateConfiguration();. above line will solve your problem.
On the other hand if you want to publish your application for higher api level, follow link below:
#Override
protected void attachBaseContext(Context newBase){
Configuration configuration = new Configuration(newBase.getResoureces().getConfiguration());
configuration.setLocale(/* selected locale which you have to get from user or your app configuration*/);
super.attachBaseContext(newBase.createConfigurationContext(configuration));
}
Override above method for each activity which you have declared;

java.lang.Exception when implementing method in android activity

This might be a very naive question but I can't get this java.lang.Exception error to go away. I also just started learning java and android so... this might be an easy problem to solve.
So I have a main activity in android and I want to implement a weka ml classifier within the app. Right now I'm just trying to load some data.
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ml_classifiers ml_object = new ml_classifiers();
int number = ml_object.loadData();
Trying to load data...
public class ml_classifiers {
public int loadData() {
ConverterUtils.DataSource source = new ConverterUtils.DataSource("C:/Users/Seth/Desktop/iris.arff");
Instances data = source.getDataSet();
int num = data.numInstances();
return num;
}
}
Why does java.lang.exception occur?

Why does java.lang.exception occur?
In the future, when you encounter crashes, use LogCat to examine the Java stack trace associated with the crash. If you do not understand the stack trace or otherwise cannot identify the problem, and you want help here, post the stack trace along with the code. As it stands, we have to guess exactly what is going wrong in your app.
In this case, while you may be crashing elsewhere, you will definitely crash with:
ConverterUtils.DataSource source = new ConverterUtils.DataSource("C:/Users/Seth/Desktop/iris.arff");
assuming that this is code in your Android app.
You are attempting to read data from C:/Users/Seth/Desktop/iris.arff. That is a path to a file on a Windows machine. Android is not Windows. There are ~2 billion Android devices in use, and none of them have access to files on your Windows' machine's desktop.
You need to get this data onto the Android device, such as:
by putting it in the assets/ directory in your module (to package it with your app), then using AssetManager to get an InputStream on that asset, hopefully passing that directly to ConverterUtils.DataSource
downloading the file from the Internet, perhaps into internal storage (e.g., getCacheDir())
expecting the user to copy the file onto their device by hand, such as via external storage

Are Activity/Fragment Transitions compatible with pre-Lollipop devices?

I'm trying to make an Activity Transition using Shared Elements on a pre-Lollipop device (4.x). Is it possible? So far, I'm trying this:
public class RewardDetail extends ActionBarActivity {
#Override
public void onCreate(final Bundle savedInstanceState) {
...
ViewCompat.setTransitionName(imageView, TRANSITION_NAME);
}
...
public static void launch(ActionBarActivity activity, View transitionView, WelcomeReward detailData) {
ActivityOptionsCompat options = ActivityOptionsCompat.makeSceneTransitionAnimation(activity, transitionView, TRANSITION_NAME);
Intent intent = new Intent(activity, RewardDetail.class);
intent.putExtra(PARAM_DATA, detailData);
ActivityCompat.startActivity(activity, intent, options.toBundle());
}
}
called by:
#Override
public void onClick(final View v) {
int position = recyclerView.getChildPosition(v);
WelcomeReward welcomeReward = data.get(position);
RewardDetail.launch(WelcomeRewardActivity.this, v.findViewById(R.id.reward_view), welcomeReward);
}
But it results in a "regular" transition (no shared element). Any ideas?
EDIT
According to this video, it could be done:
https://www.youtube.com/watch?v=RhiPJByIMrM&index=8&list=WL
Is there a library already implementing this for pre Lollipop ?

No, Activity/Fragment Transitions are not possible on pre-Lollipop devices. According to the documentation:
Start an activity with additional launch information, if able.
In Android 4.1+ additional options were introduced to allow for more control on activity launch animations. Applications can use this method along with ActivityOptionsCompat to use these animations when available. When run on versions of the platform where this feature does not exist the activity will be launched normally.
See also George Mount's answer to this StackOverflow question.

You can check out this library for activity and fragment transitions for pre lollipop devices
dependencies {
compile 'com.albinmathew:PreLollipopTransition:1.1.2'
}
https://github.com/albinmathew/PreLollipopTransition

Although the fancy Lollipop Activity/Fragment transitions are not available pre-Lollipop (without the use of a 3rd party library), you can still override the animation used to transition between activities.
Just before/after you start invoke startActivity() you can make a call to [Activity.overridePendingTransition](http://developer.android.com/reference/android/app/Activity.html#overridePendingTransition(int, int)). When you leave your activity, call the same method.
Similarly you can use ActivityOptionsCompat to define a custom animation to use during a transition.
ActivityOptionsCompat opts =
ActivityOptionsCompat.makeCustomAnimation(getActivity(), R.anim.in, R.anim.out);
startActivity(intent, opts.toBundle());

There is a support library, but it does not support (all) transitions on Android versions below 5.0. There are however some alternatives:
Unofficial Compatibility libraries https://github.com/andkulikov/transitions-everywhere
https://github.com/takahirom/PreLollipopTransition
https://github.com/lgvalle/Material-Animations
Android KitKat http://www.doubleencore.com/2013/11/new-transitions-framework/ and a
sample found in your SDK samples folder.
Posted earlier to a duplicate of this question here: https://stackoverflow.com/a/27344471/1683141

Mac Address or IMEI on Libgdx Android App

I'm developing a APP to android using LIGBDX, i need to get the MAC ADDRES or IMEI or any other unique code from the phone. When using NetworkInterface from Java.net works fine on Desktop project, but on Android it doesnt work, so i saw on the internet the WifiManger,
is a API (i guess) from android.
WifiManager wifiMan = (WifiManager) this.getSystemService( Context.WIFI_SERVICE);
WifiInfo wifiInf = wifiMan.getConnectionInfo();
String macAddr = wifiInf.getMacAddress();
And it seens it works, BUT i'm using LIBGDX and i not getting to import Android.Net on my project, saw one guys talking when i try to references pure android on LIbgdx i have to work only on android not in Core, but i dont know how to do this.
Maybe add Wifimanager.java into library i tried that but not work.
Note: i am using Gdx Net and edited the manifest, i am dowloading and send data from iternet, i cant do only the mac part

Try this:
1)
Declare an Interface in your core project with a method to retrieve the number you want.
public interface IActivityRequestHandler {
public String getUniqueId();
}
In your core project, add a constructor to your Game class that takes a IActivityRequestHandler as a parameter:
public abstract class MyGame extends Game {
...
public IActivityRequestHandler handler;
...
public MyGame(IActivityRequestHandler handler){
this.handler = handler;
}
You will use "handler" to call platform specific methods.
2)
Make the android MainActivity implement this interface and write the methood to return the value you need.
3) In your Android MainActivity, when you instantiate your AndroidGame, pass the MainActivity as a parameter:
public class MainActivity extends AndroidApplication implements IActivityRequestHandler{
...
ApplicationListener game;
....
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
game = new AndroidMyGame(this);
...
}
public String getUniqueId(){
return uniqueId;
}
...
}
4) Now when you need the id from the core you call: handler.getUniqueId() (from MyGame class)
This will be calling the method on your Android MainActivity if you are running the game from an Android Device.
Important notes:
1) This should work if you don't have any contraints regarding the UI Thread in Android.
This is, to return a value it should work. If you call anything that can only be called in the UIThread this won't work and, aditionally, you have to use a Handler to communicate between threads.
2) Your Desktop version will also have to implement IActivityRequestHandler.
3) Getting a unique id in Android devices is something I haven't found a nice solution yet.
a) Tablets, unless they have a phone line, don't have IMEI or telephone number.
b) MAC Addresses are not unique (you have 3g, wifi, bluetooth) and sometimes are not available for example if wifi is turned off.
4) You might be better off generating a unique id yourself and storing it on the phone.
google "Java UUID".