Develop Reference

Webview Splash screen doen't show once as expected

Am trying to create a webview app displaying a splash screen once after the first lunch. Initially once i open the app the splash screen will show up then after 5 seconds it will load main activity VaultActivity, but after i have added the line of code to check if splash screen 'SplashScreen' has been launched before, the app stopped loading VaultActivity using the SPLASH_TIME_OUT i set and also the splash screen still shows up anytime i lunch the app.
Initially
public class SplashScreen extends Activity {
private static int SPLASH_TIME_OUT = 5000; // Splash screen timer
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_splash);
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
// Start main activity
Intent intent = new Intent(SplashScreen.this, VaultActivity.class);
startActivity(intent);
finish();
}
}, SPLASH_TIME_OUT);
}
}
Currently
public class SplashScreen extends Activity {
private static int SPLASH_TIME_OUT = 5000; // Splash screen timer
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_splash);
SharedPreferences pref = getSharedPreferences("ActivityPREF", Context.MODE_PRIVATE);
if(pref.getBoolean("activity_executed", false)){
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
// Start main activity
Intent intent = new Intent(SplashScreen.this, VaultActivity.class);
startActivity(intent);
finish();
}
}, SPLASH_TIME_OUT);
} else {
SharedPreferences.Editor ed = pref.edit();
ed.putBoolean("activity_executed", true);
ed.commit();
}
}
}
My Manifest
<activity
android:name=".SplashScreen"
android:launchMode="singleTask"
android:label="#string/app_name"
android:screenOrientation="portrait" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".VaultActivity"
android:label="#string/app_name"
android:screenOrientation="portrait">
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.BROWSABLE" />
<data android:scheme="http"
android:host="example.com"
android:pathPrefix="/androidmobile" />
</intent-filter>
</activity>

:) you need just adding startActivity in else section.
public class SplashScreen extends Activity {
private static int SPLASH_TIME_OUT = 5000; // Splash screen timer
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_splash);
SharedPreferences pref = getSharedPreferences("ActivityPREF", Context.MODE_PRIVATE);
final SharedPreferences.Editor ed = pref.edit()
if(pref.getBoolean("activity_executed", false)){
//ed.putBoolean("activity_executed", true);
//ed.commit();
Intent intent = new Intent(SplashScreen.this, VaultActivity.class);
startActivity(intent);
finish();
} else {
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
// Start main activity
Intent intent = new Intent(SplashScreen.this, VaultActivity.class);
startActivity(intent);
ed.putBoolean("activity_executed", true);
ed.commit();
finish();
}
}, SPLASH_TIME_OUT);
}
}
}

You have to call the startActivity in your else.

NotificationListenerService sendBroadcast not working?

I'm trying for well over 10 hours now and I can't seem to think about anyhting else. I tried every possible example on the internet, but to no avail.
I have NotificationMonitor class extending NotificationListenerService and I wanted to send message from this service to main activity(and possible other activities and services in the future) using Intent mechanism. I post code below:
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.testpackage.test">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<service android:name=".NotificationMonitor"
android:label="#string/app_name"
android:permission="android.permission.BIND_NOTIFICATION_LISTENER_SERVICE">
<intent-filter>
<action android:name="android.service.notification.NotificationListenerService" />
</intent-filter>
</service>
</application>
</manifest>
MainActivity.java
public class MainActivity extends Activity {
private TextView txtView;
private NotificationReceiver nReceiver;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
txtView = (TextView) findViewById(R.id.textView);
//create receiver
nReceiver = new NotificationReceiver();
IntentFilter filter = new IntentFilter();
filter.addAction("com.testpackage.test.NOTIFICATION_MONITOR");
registerReceiver(nReceiver,filter);
}
#Override
protected void onDestroy() {
super.onDestroy();
unregisterReceiver(nReceiver);
}
public void buttonClicked(View v){
if(v.getId() == R.id.btnTestBroadcast){
//send test intent without category
Log.d("ActivityMain","Button clicked");
Intent i = new Intent("com.testpackage.test.NOTIFICATION_MONITOR");
sendBroadcast(i);
}
}
class NotificationReceiver extends BroadcastReceiver{
#Override
public void onReceive(Context context, Intent intent) {
Log.d("ActivityMain","Intent received: "+intent.getAction()+" has extra: "+intent.hasExtra("info"));
if (intent.hasCategory("com.testpackage.test.TEST_CATEGORY")) {
if (intent.hasExtra("info")) {
txtView.setText(intent.getStringExtra("info"));
}
}
}
}
}
NotificationMonitor.java
public class NotificationMonitor extends NotificationListenerService {
private NotificationMonitorReceiver receiver;
#Override
public void onCreate() {
super.onCreate();
receiver = new NotificationMonitorReceiver();
IntentFilter filter = new IntentFilter();
filter.addAction("com.testpackage.test.NOTIFICATION_MONITOR");
registerReceiver(receiver,filter);
}
#Override
public void onDestroy() {
super.onDestroy();
unregisterReceiver(receiver);
}
#Override
public void onNotificationPosted(StatusBarNotification sbn) {
//do something
sendInfo("notification posted");
}
#Override
public void onNotificationRemoved(StatusBarNotification sbn) {
//do something
sendInfo("notification removed");
}
#Override
public void onListenerConnected() {
//service created and listener connected
Log.d("NM","Listener connected!");
sendInfo("listener connected");
}
private void sendInfo(String info) {
Log.d("NM", "sendInfo called!");
Intent i = new Intent("com.testpackage.test.NOTIFICATION_MONITOR");
i.addCategory("com.testpackage.test.TEST_CATEGORY");
i.putExtra("info", info);
sendBroadcast(i);
}
class NotificationMonitorReceiver extends BroadcastReceiver{
#Override
public void onReceive(Context context, Intent intent) {
//no categories intents get replied
Log.d("NM","Intent received: "+intent.getAction()+" has categories: "+(intent.getCategories()!=null));
if (intent.getCategories() == null) {
Intent i = new Intent("com.testpackage.test.NOTIFICATION_MONITOR");
i.addCategory("com.testpackage.test.TEST_CATEGORY");
sendBroadcast(i);
}
}
}
}
After running this app in debug mode of course I need to re-enable notification permissions, so when I do I see in logcat:
10-10 16:22:46.428 7330-7381/com.testpackage.test D/NM: Listener connected!
10-10 16:22:46.428 7330-7381/com.testpackage.test D/NM: sendInfo called!
well, I should receive broadcast in my application, shouldn't I?
After I click button:
10-10 16:22:57.607 7330-7330/com.testpackage.test D/ActivityMain: Button clicked
10-10 16:22:57.612 7330-7330/com.testpackage.test D/ActivityMain: Intent received: com.testpackage.test.NOTIFICATION_MONITOR has extra: false
10-10 16:22:57.619 7330-7330/com.testpackage.test D/NM: Intent received: com.testpackage.test.NOTIFICATION_MONITOR has categories: false
so the Intent is properly created and send from main activity, received back by the same activity and NotificationListenerService, has no categories so should get replied but nothing happens like when sendInfo method is called.
Please help, I have no other ideas about what might be wrong.
edit: I tested with regular services and of course Broadcasts are working just fine. Is there by chance any possibility that you just can't sendBroadcast from this particular extended service class?

Oficially, I'm a moron. Answer is: I didn't set up Category filter in IntentFilter and this is why I received zero properly sent intents from my class. So, long story short, to "fix" this mistake all one needs to do is add:
filter.addCategory("com.testpackage.test.TEST_CATEGORY");
and that's it. Thank you for your attention.

How to start launcher activity from another activity?

I created one app with two activities when I run app It opens first launcher activity In this activity I added textViewon clicking this textViewsecond activity is opened,
At the second activity again I added one textView on clicking that textView I expected to launch my first activity(Launcer activity) but this doesn't happens? Why? My Manifest file is as follows
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.adbs.abs.dhanagarmaza" >
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme" >
<activity
android:name=".LoginRegi"
android:label="#string/app_name"
android:theme="#style/AppTheme.NoActionBar" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".Register"
android:label="#string/app_name"
android:theme="#style/AppTheme.NoActionBar" >
<intent-filter>
<action android:name="com.adbs.abs.REGISTER" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
</manifest>
My LoginRegi(Second activity java file 'DEFAULT activity')
protected void onCreate(Bundle registerBundle) {
super.onCreate(registerBundle);
setContentView(R.layout.register);
// If user wants to login then on click "Login Me" textView open activity(LoginRegi.xml)
loginMe = (TextView)findViewById(R.id.tvLoginMe);
loginMe.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
Intent openLoginRegi = new Intent("android.intent.action.MAIN");
startActivity(openLoginRegi);
}
});
}
and LoginRegi.java (First activity 'LAUNCHER activity')
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login_regi);
// On click signup textView => Open activity (register.xml)
signUp = (TextView)findViewById(R.id.tvSignUp);
signUp.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
Intent openRegister = new Intent("com.adbs.abs.REGISTER");
startActivity(openRegister);
}
});
}

Activity 1:-
public class MainActivity extends Activity {
TextView tvOne;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tvOne=(TextView)findViewById(R.id.tvOne);
tvOne.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent=new Intent(getApplicationContext(),Main2Activity.class);
startActivity(intent);
}
});
}
}
Activity 2:-
public class Main2Activity extends Activity {
TextView tvTwo;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
tvTwo=(TextView)findViewById(R.id.tvTwo);
tvTwo.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent=new Intent(getApplicationContext(),MainActivity.class);
startActivity(intent);
}
});
}
}

Intent i =new Intent(this,MainActivity.class);
startActivity(i);

you can post your code so we can get exact problem because ..
by finish(); you can get your prevous activity back either you can do it by Intent

My LoginRegi(Second activity java file 'DEFAULT activity')
protected void onCreate(Bundle registerBundle) {
super.onCreate(registerBundle);
setContentView(R.layout.register);
// If user wants to login then on click "Login Me" textView open activity(LoginRegi.xml)
loginMe = (TextView)findViewById(R.id.tvLoginMe);
loginMe.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
Intent openLoginRegi = new Intent(Register.this,LoginRegi.class);
startActivity(openLoginRegi);
}
});
}
and LoginRegi.java (First activity 'LAUNCHER activity')
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login_regi);
// On click signup textView => Open activity (register.xml)
signUp = (TextView)findViewById(R.id.tvSignUp);
signUp.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
Intent openRegister = new Intent(LoginRegi.this,Register.class);
startActivity(openRegister);
}
});
}

Android: Application crash on Start (Opening intent on Button)

I am trying to open another activity through Intent on Button press.
But the app crashes every time on launch.
IntentTest.java:
package com.example.intenttest;
public class IntentTest extends Activity {
Button b1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_intent_test);
b1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent2 = new Intent(IntentTest.this, IntentTest2.class);
startActivity(intent2);
}
});
}
}
IntentTest2.java:
package com.example.intenttest;
public class IntentTest2 extends Activity {
TextView textView1;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_intent_test2);
textView1=(TextView)findViewById(R.id.textView1);
}
}
Manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.intenttest"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="11"
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.intenttest.IntentTest"
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:label="#string/app_name" android:name="com.example.intenttest.IntentTest2" />
</application>
</manifest>
Here is the LogCat where the app crashes:
12-18 11:59:59.563: W/Trace(20985): error opening trace file: No such file or directory (2)
12-18 11:59:59.623: D/AndroidRuntime(20985): Shutting down VM
12-18 11:59:59.623: W/dalvikvm(20985): threadid=1: thread exiting with uncaught exception (group=0x40c8d930)
12-18 11:59:59.633: E/AndroidRuntime(20985): FATAL EXCEPTION: main
12-18 11:59:59.633: E/AndroidRuntime(20985): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.intenttest/com.example.intenttest.IntentTest}: java.lang.NullPointerException
I cant find out what is wrong. Please help.

Because you did not initialize b1(Button)
b1 = (Button)findViewById(R.id.button_id);
b1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent2 = new Intent(IntentTest.this, IntentTest2.class);
startActivity(intent2);
}
});

you forgot to initialze button object in IntentTest
b1=(Button)findViewById(R.id.b1);
like this way with your button id.

Button b1 is not initialized. So it's null.

Fisrt initialize your button
Button b1 = (Button)findViewById(R.id.Buttonid);
b1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent2 = new Intent(IntentTest.this, IntentTest2.class);
startActivity(intent2);
}
});
else directly use like this
findViewById(R.id.Buttonid).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent2 = new Intent(IntentTest.this, IntentTest2.class);
startActivity(intent2);
}
});

You did not initialize your button b1 in IntentTest class,
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_intent_test);
b1=(Button)findViewById(R.id.your_btn_name);
b1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent2 = new Intent(IntentTest.this, IntentTest2.class);
startActivity(intent2);
}
});
}

Switch between activities in Android

I want the user to be able to tap a button and be taken to a different activity. I've used similar code before in another app, but every time I press the button now the app crashes. In the main menu I have:
Button testButton = (Button) findViewById(R.id.testButton);
testButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
startActivity(new Intent("de.vogella.android.c2dm.simpleclient.TEST"));
}
});
In the manifest:
<activity
android:name=".TestClass"
android:label="#string/app_name" >
<intent-filter>
<action android:name="de.vogella.android.c2dm.simpleclient.TEST" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
TestClass.java is:
package de.vogella.android.c2dm.simpleclient;
import android.app.Activity;
import android.os.Bundle;
public class TestClass extends Activity {
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
}

Try this: In the onClick modify your first class to this:
Button testButton = (Button) findViewById(R.id.testButton);
testButton.setOnClickListener(new View.OnClickListener() {
final ClassName changeAct = this;
public void onClick(View v) {
// TODO Auto-generated method stub
Intent i = new Intent();
i.setClass(changeAct, TEST.class); //Change TEST.class to the name of the class you want it to go to.
startActivity(i);
stop();
}
});

Intent intent = new Intent (CurrentActivity.this, TestClass.class);
startActivity(intent);
If your TestClass is in another package just put your package in front.
Intent intent = new Intent (CurrentActivity.this, de.vogella.android.c2dm.simpleclient.TestClass.class);
startActivity(intent);
Declare the activity in manifest like this:
<activity
android:name="de.vogella.android.c2dm.simpleclient.TestClass"
</activity>