Develop Reference

Android : what category of intent filter should i use

In the second and third activity, in the intent filter what should i use in category.In the second activity i used default but after making third activity i do not know what category should i use.
This is the first android app i am trying to make.Please help me,which categoty should i use in second and third activity.
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="csimplifyit.mobileapp.myschool">
<!-- To auto-complete the email text field in the login form with the user's emails -->
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
<uses-permission android:name="android.permission.READ_PROFILE" />
<uses-permission android:name="android.permission.READ_CONTACTS" />
<!-- for json call -->
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:icon="#mipmap/login"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity
android:name=".login.Login"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".login.Menu"
android:label="#string/second_activity">
<intent-filter>
<action android:name="csimplifyit.mobileapp.myschool.login.Menu" />
<category android:name="android.intent.category. " />
</intent-filter>
</activity>
<activity
android:name=".login.Attendance"
android:label="#string/attendance_activity">
<intent-filter>
<action android:name="csimplifyit.mobileapp.myschool.login.Attendance" />
<category android:name="android.intent.category. " />
</intent-filter>
</activity>
</application>

Most likely, you get rid of the second and third <intent-filter> elements entirely. Only have <intent-filter> elements on activities that you expect other apps to link to. You do not need action strings for starting your own activities -- you can use explicit Intents (e.g., new Intent(this, csimplifyit.mobileapp.myschool.login.Menu.class)).
If, for some reason, you are expecting other developers to directly start your Menu or Attendance activities, then the simplest thing is to put them in the DEFAULT category as well. A call to startActivity() automatically adds the DEFAULT category to the Intent, if the Intent has not specified another category.

Android manifest for USBAccesory

I am making an app that communicates with a piece of usb hardware made by my company (this is the only app allowed to talk to the usb accessory, it's not a public api). I am having difficulties setting up the proper launch modes in the manifest.
There are three components to the app: the main activity, a login activity, and the USBService.
I'm assuming the intent for the main goes to the login activity, and the intent for the usb goes to the USBService, but I am not sure if I do this, will this start the service if the app is not running? More over, if it does, how do I fetch an already existing service?
What type of structure should I be looking at for the manifest file? (specifically, intent-filters, and appropriate launch modes... I've read a few documents about the launch modes but I am still not sure I quite understand... There should only ever be at most one instance of each activity/service, and they need to communicate together.
edit: it is not necessary for communications to start before the app is open, nor is it necessary to launch the app automatically when the usb is connected.
edit: my manifest as it stands, looks like:
<uses-feature android:name="android.hardware.usb.accessory" />
<uses-sdk
android:minSdkVersion="15"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name" >
<activity
android:name="mainpackage.MainActivity"
android:label="#string/app_name"
android:launchMode="singleTop">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<intent-filter>
<action android:name="android.hardware.usb.action.USB_ACCESSORY_ATTACHED" />
</intent-filter>
<meta-data
android:name="android.hardware.usb.action.USB_ACCESSORY_ATTACHED"
android:resource="#xml/accessory_filter" />
</activity>
<activity
android:name="mainpackage.LoginActivity"
android:label="#string/title_activity_login"
android:windowSoftInputMode="adjustResize|stateVisible" >
</activity>
<service android:name="updater.USBService"
android:exported="false" >
<!--
-->
</service>
</application>

in your manifest add
<manifest ...>
<uses-feature android:name="android.hardware.usb.host" />
<uses-sdk android:minSdkVersion="12" />
In this case, the following resource file should be saved in res/xml/device_filter.xml and specifies that any USB device with the specified attributes should be filtered:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<usb-device vendor-id="1234" product-id="5678" class="255" subclass="66" protocol="1" />
</resources>
Hope this help.

Your manifest looks good,
I think you make a good choice for putting the intent-filter "android.hardware.usb.action.USB_ACCESSORY_ATTACHED" in the mainActivity and start the application in this activity,
and again I think it's a good choice to start your mainActivity in SingleTop launch mode,
because if an instance of the mainActivity already exists at the top of the current task, the system going to launch this activity, no new instance of this activity will be created.
For a best understanding of the different launch mode available in android,
I think this link may help you :
http://www.intridea.com/blog/2011/6/16/android-understanding-activity-launchmode
To make a long story short I think you'll be all set with this manifest as is.

To Use Android Devices min SDK version should be set to 12 and need to declare following line in AndroidManifest.xml file
<>
<uses-sdk android:minSdkVersion="<version>" />
...
<application>
<uses-library android:name="com.android.future.usb.accessory" />
<activity ...>
...
<intent-filter>
<action android:name="android.hardware.usb.action.USB_ACCESSORY_ATTACHED" />
</intent-filter>
<meta-data android:name="android.hardware.usb.action.USB_ACCESSORY_ATTACHED"
android:resource="#xml/accessory_filter" />
</activity>
</application>

Android app doesn't launch the main activity and says app isnt installed

So im kinda new to android programming and i dont really know why i cant run the main activity when i have a permission tag under the activity. this is my code under the manifest file:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.lab08b_awahla"
android:versionCode="1"
android:versionName="1.0" >
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="com.example.DANGEROUS_ACTION" />
<permission
android:name="com.example.DANGEROUS_ACTION"
android:label="permission"
android:protectionLevel="dangerous" />
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.example.lab08b_awahla.MainActivity"
android:label="#string/app_name"
android:permission="com.example.DANGEROUS_ACTION" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<intent-filter>
<action android:name="com.example.DANGEROUS_ACTION" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
</manifest>

This is obvious. If you are providing a security tag for activity anyone who wants to launch this activity has to have such privilege. Home screen app doesn't have (even don't known) your permission tag so this is a problem.

According to the docs for the <activity> tag
android:permission
The name of a permission that clients must have to launch the activity or otherwise get it to respond to an intent. If a caller of startActivity() or startActivityForResult() has not been granted the specified permission, its intent will not be delivered to the activity.
This leads me to think that you misunderstand the use of this attribute.

Finding the "Android class name" in "AndroidManifest.xml" generated by Unity3D

When configuring a "Android Native App" in a Facebook app, they require the Android Class Name. If you created the Android APK from Unity3D, how do you know what class to use?
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:installLocation="preferExternal" package="--------------" android:versionName="1.02" android:versionCode="8">
<supports-screens android:smallScreens="true" android:normalScreens="true" android:largeScreens="true" android:xlargeScreens="true" android:anyDensity="true" />
<application android:icon="#drawable/app_icon" android:label="#string/app_name" android:debuggable="true">
<activity android:name="com.unity3d.player.UnityPlayerProxyActivity" android:label="#string/app_name" android:configChanges="fontScale|keyboard|keyboardHidden|locale|mnc|mcc|navigation|orientation|screenLayout|screenSize|smallestScreenSize|uiMode|touchscreen" android:screenOrientation="landscape">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name="com.unity3d.player.UnityPlayerActivity" android:label="#string/app_name" android:configChanges="fontScale|keyboard|keyboardHidden|locale|mnc|mcc|navigation|orientation|screenLayout|screenSize|smallestScreenSize|uiMode|touchscreen" android:screenOrientation="landscape">
</activity>
<activity android:name="com.unity3d.player.UnityPlayerNativeActivity" android:label="#string/app_name" android:configChanges="fontScale|keyboard|keyboardHidden|locale|mnc|mcc|navigation|orientation|screenLayout|screenSize|smallestScreenSize|uiMode|touchscreen" android:screenOrientation="landscape">
<meta-data android:name="android.app.lib_name" android:value="unity" />
<meta-data android:name="unityplayer.ForwardNativeEventsToDalvik" android:value="false" />
</activity>
<activity android:name="com.unity3d.player.VideoPlayer" android:label="#string/app_name" android:configChanges="fontScale|keyboard|keyboardHidden|locale|mnc|mcc|navigation|orientation|screenLayout|screenSize|smallestScreenSize|uiMode|touchscreen" android:screenOrientation="landscape">
</activity>
<!-- ACTIVITIES -->
<activity android:name="com.prime31.FacebookProxyActivity" />
<!-- META-DATA -->
</application>
<!-- PERMISSIONS -->
<uses-permission android:name="android.permission.INTERNET" />
<uses-feature android:glEsVersion="0x00020000" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-feature android:name="android.hardware.sensor.accelerometer" />
<uses-feature android:name="android.hardware.touchscreen" />
<uses-feature android:name="android.hardware.touchscreen.multitouch" android:required="false" />
<uses-feature android:name="android.hardware.touchscreen.multitouch.distinct" android:required="false" />
<uses-sdk android:minSdkVersion="8" android:targetSdkVersion="16" />
</manifest>

This field should be your main activity (associated with MAIN and LAUNCHER). In this case, I think it would be com.unity3d.player.UnityPlayerProxyActivity.
This is mainly necessary if you use native deep links (so the FB app can create an intent that directly calls your activity). In that respect, any publicly accessible Activity in your app will do.

The main activity's tag should contain an intent-filter tag with the action android.intent.action.MAIN and the category android.intent.category.LAUNCHER.
Description of the intent-filter tag (from documentation):
Specifies the types of intents that an activity, service, or broadcast
receiver can respond to. An intent filter declares the capabilities of
its parent component — what an activity or service can do and what
types of broadcasts a receiver can handle. It opens the component to
receiving intents of the advertised type, while filtering out those
that are not meaningful for the component. Most of the contents of the
filter are described by its <action>, <category>, and <data>
subelements.
For a more detailed discussion of filters, see the separate Intents
and Intent Filters document, as well as the Intents Filters section in
the introduction.
The main activity of an Android application has an intent-filter with the category LAUNCHER which basically tells that the activity can "launch the app" (in other words, that it is the launcher/entry).
The activity tag should look something like this:
<activity android:name="ActivityClassName" android:label="Activity title">
<!-- The intent filter -->
<intent-filter>
<!-- The action -->
<action android:name="android.intent.action.MAIN"/>
<!-- The category -->
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
By looking at your AndroidManifest.xml, you can conclude that the main Activity of your app is the com.unity3d.player.UnityPlayerProxyActivity Activity, because it contains an intent-filter matching those criterias.
Good luck with your game!

Using "UnityPlayerProxyActivity" is no longer true for all unity versions. You may have to use "UnityPlayerActivity" instead.
Details:
If you export an Android project from unity you may find three classes in src:
UnityPlayerActivity
UnityPlayerNativeActivity
UnityPlayerProxyActivity
"UnityPlayerProxyActivity" and "UnityPlayerNativeActivity" have been deprecated since Unity 5.0 beta12, thus you have to use "UnityPlayerActivity" instead.
In Facebook type in:
[tld.yourdomain.game].UnityPlayerActivity
Replace the [...] part with your app specifics of course. Attention: If you have some plugins/extensions that fiddle around with your manifest, then this may be different.
UPDATE:
In newer Versions of the Facebook SDK for Unity (tested with 7.9.4) you can simply search for "FacebookSettings" in your Assets folder and it will tell you what Class Name to use ("com.facebook.unity.FBUnityDeepLinkingActivity" for example).

BackButton quit the application

I'm experiencing a trouble on my app, my backButton quit the application.
My application is a SyncService, everything seems to be great in the Manifest, i check for one day with no response...
I already check if the launchmode change something, i test the 4 and nothing append...
If someone can have a look on the manifest, it would be great :
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.smile.android.ldapsync" android:versionCode="12" android:versionName="1.5">
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
<uses-permission android:name="android.permission.USE_CREDENTIALS" />
<uses-permission android:name="android.permission.MANAGE_ACCOUNTS" />
<uses-permission android:name="android.permission.AUTHENTICATE_ACCOUNTS" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WRITE_SETTINGS" />
<uses-permission android:name="android.permission.WRITE_SECURE_SETTINGS" />
<uses-permission android:name="android.permission.READ_CONTACTS" />
<uses-permission android:name="android.permission.WRITE_CONTACTS" />
<uses-permission android:name="android.permission.READ_SYNC_STATS" />
<uses-permission android:name="android.permission.READ_SYNC_SETTINGS" />
<uses-permission android:name="android.permission.WRITE_SYNC_SETTINGS" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /><application android:icon="#drawable/icon" android:label="#string/app_name" android:debuggable="true" android:enabled="true" android:persistent="true">
<service android:name="com.smile.android.ldapsync.authenticator.LDAPAuthenticationService" android:exported="true" android:debuggable="true">
<intent-filter>
<action android:name="android.accounts.AccountAuthenticator" />
</intent-filter>
<meta-data android:name="android.accounts.AccountAuthenticator" android:resource="#xml/authenticator" />
</service>
<service android:name="com.smile.android.ldapsync.syncadapter.SyncService" android:exported="true" android:debuggable="true">
<intent-filter>
<action android:name="android.content.SyncAdapter" />
</intent-filter>
<meta-data android:name="android.content.SyncAdapter" android:resource="#xml/syncadapter" />
</service>
<activity android:name="com.smile.android.ldapsync.authenticator.LDAPAuthenticatorActivity" android:label="#string/ui_activity_title" android:excludeFromRecents="true">
android:excludeFromRecents="true"
<!--
No intent-filter here! This activity is only ever launched by
someone who explicitly knows the class name
-->
</activity>
</application>
<uses-sdk android:minSdkVersion="5" />
</manifest>
Thank you ;)

Did you tried overriding onBackPressed ?
#Override
public void onBackPressed() {
return;
}

if you press back button while on the "main" activity (the first one you launched aka the bottom of your activity stack) the OS understand this as "the user is done and won't be back anytime soon" opposed as "home" button which is understood as "maybe the user wants to check something else before resuming the app"
So, if you DO NOT want your app to "terminate" (an android app terminates only when the OS kills it, otherwise it will lurk in memory until recalled) you need to override the back button pressed callback
public void onBackPressed()
which the api doc describes as:
"Called when the activity has detected the user's press of the back key. The default implementation simply finishes the current activity, but you can override this to do whatever you want."
You might just ignore the event and absorb it like timo schloesser suggested or you can do whatever is most appropriated (like, launching another activity or killing services before leaving the screen)
EDIT: you might also want to check the "moveTaskToBack" method inherited from Activity class. I have never used it but it might be useful to your problem.