multiple Instance running of the same app in kitkat android

Question

Is there any way to stop app running multiple instance? I have tried single instance in manifest also but did not succeed.

I have make a demo app for fetching Facebook friends. It works good in 4.2.2 and other but in kitkat 4.4.2 after login when i fatch friends it crashes and in DDMS app shows multiple instance running of the same app.

Can anyone help me or guide what is the issue?

Here is the manifest file

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk
    android:minSdkVersion="8"
    android:targetSdkVersion="18" />


<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />


<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme"
    android:name="com.example.MyApplication" >


    <activity
        android:name=".Splash"
        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="com.example.ui.newHome"
        android:screenOrientation="portrait" />


     <activity
        android:name="com.example.ui.FriendsList"
        android:screenOrientation="portrait" />


    <activity
        android:name="com.facebook.LoginActivity"
        android:label="@string/app_name"
        android:theme="@android:style/Theme.Translucent.NoTitleBar" />

    <meta-data
        android:name="com.facebook.sdk.ApplicationId"
        android:value="@string/app_id" />
</application>

Whitley

try android:launchMode="singleTask" for your activty in your manifest – Swine

i have tried with it also but doesnt work.i am facing issue in kitkat only – Whitley

There is always only one instance of an application. There may be more than one instance of an activity for an application. – Calcic

android:launchMode="singleInstance" in your activity in manifest – Rabies

Answer 1

You should use as per official documentation mode="singleTask" or mode="singleInstance".

singleTask

The system creates the activity at the root of a new task and routes the intent to it. However, if an instance of the activity already exists, the system routes the intent to existing instance through a call to its onNewIntent() method, rather than creating a new one.

singleInstance

Same as "singleTask", except that the system doesn't launch any other activities into the task holding the instance. The activity is always the single and only member of its task.

http://developer.android.com/guide/topics/manifest/activity-element.html

If your problem persist please post the exception stack trace.

Distribute

Answer 2

Try the following in the launcher activity in onCreate

if(!isTaskRoot()){
            finish();
            return;
        }

This will prevent the multiple instance of same application.

Errata

You shouldn't need to do that – Distribute

Well this ensures a single instance of your app and i'm sure the question was regarding that only. isn't it? – Errata

The android framework provides a way to archive that, which doesn't even require a line of code. – Distribute

Answer 3

In your manifest file include
android:launchMode="singleInstance"

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