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Simple app works correctly on Android Emulator but crashes on a real device [duplicate]

This question already has answers here:
"Could not find a method .. in the activity class .. for onClick handler"
(3 answers)
Crossfading 2 views using a button in Android
(1 answer)
Closed 5 years ago.
Real Device: LG G2, android 4.4.2, OPENGL ES v3.0
Emulated Device: Nexus 5X, android 7.1.1, OPENGL ES v2.0 (Hardware)
Apps that involve modifying the views (setting text, making views visible/invisible, etc) run flawlessly on the emulator, but crash on the real device (on button press).
Apps that don't involve modifying any of these work fine on the real device.
I've tried it with this simple app:
(activity_main.xml)
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.cmnd97.test.MainActivity">
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="method"
android:text="Press me" />
</LinearLayout>
(MainActivity.java)
package com.cmnd97.test;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.Button;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
protected void method() {
Button btn = (Button) findViewById(R.id.button);
btn.setText("Pressed");
}
}
This particular app crashes on button press without printing any error message to the debugger, however another app which involved hiding/showing a button printed this error:
Failed to set EGL_SWAP_BEHAVIOR error=EGL_BAD_MATCH

In your manifest file and gradle you need to set the minimun sdk target, so in your case could be works sdk 15 or 16
defaultConfig {
minSdkVersion 15
targetSdkVersion 25
}

Interrupt car radio android bluetooth

We're trying to play audio alerts from our android app (traffic information) over bluetooth connected car stereos. If we switch the car stereo audio input to bluetooth, the app audio plays. If it is on any other source, the app audio does not play, either from the stereo or from the device.
What we want to do, is to allow users to keep the stereo audio input on DAB/FM radio or other source, but have our app audio interrupt at certain times and play these traffic information alerts, like how VOIP apps manage to do (such as Facebook messenger), and the built-in telephony phone call app manages to do.
Here is the code we are using at the moment :
MainActivity.java
package com.robbresearch.ttsandroidtest;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.content.Context;
import android.media.AudioManager;
public class MainActivity extends AppCompatActivity {
private Button speakNowButton;
private TextView textView;
TTSManager ttsManager = null;
AudioManager am;
AudioManager.OnAudioFocusChangeListener afChangeListener =
new AudioManager.OnAudioFocusChangeListener() {
public void onAudioFocusChange(int focusChange) {
if (focusChange == AudioManager.AUDIOFOCUS_LOSS_TRANSIENT) {
// Pause playback
} else if (focusChange == AudioManager.AUDIOFOCUS_GAIN) {
// Resume playback
} else if (focusChange == AudioManager.AUDIOFOCUS_LOSS) {
//am.unregisterMediaButtonEventReceiver(RemoteControlReceiver);
am.abandonAudioFocus(afChangeListener);
// Stop playback
}
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Context mContext = getApplicationContext();
ttsManager = new TTSManager();
ttsManager.init(this);
am = (AudioManager)mContext.getSystemService(Context.AUDIO_SERVICE);
// Request audio focus for playback
int result = am.requestAudioFocus(afChangeListener,
// Use the music stream.
AudioManager.STREAM_VOICE_CALL,
// Request permanent focus.
AudioManager.AUDIOFOCUS_GAIN);
if (result == AudioManager.AUDIOFOCUS_REQUEST_GRANTED) {
//am.registerMediaButtonEventReceiver(RemoteControlReceiver);
// Start playback.
}
am.setMode(AudioManager.MODE_IN_CALL);
android.os.Process.setThreadPriority(
android.os.Process.THREAD_PRIORITY_URGENT_AUDIO);
textView = (TextView) findViewById(R.id.input_text);
speakNowButton = (Button) findViewById(R.id.speak_now);
speakNowButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
String text = textView.getText().toString();
ttsManager.initQueue(text);
}
});
}
/**
* Releases the resources used by the TextToSpeech engine.
*/
#Override
public void onDestroy() {
super.onDestroy();
ttsManager.shutDown();
}
}
activity_main.xml :
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_marginBottom="10dp"
android:orientation="vertical"
android:padding="20dp" >
<TextView
android:id="#+id/input_text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="20dp"
android:ems="10"
android:padding="10dp"
android:text="Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum." />
<Button
android:id="#+id/speak_now"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Speak Now" />
</LinearLayout>
We have these additional permissions in android manifest :
<uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS"/>
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
We would greatly appreciate any advice on how to achieve this, thanks :)
We only need to support newer versions of android if necessary.

I was able to get it working with the following code :
audioM.setMode(audioM.MODE_IN_COMMUNICATION);
audioM.setBluetoothScoOn(true);
audioM.startBluetoothSco();
audioM.setSpeakerphoneOn(false);
And the following permissions :
<uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS" />
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.BROADCAST_STICKY" />
There was no need to set thread priority or request audio focus.
Note that I'm currently getting a 15 second delay between calling TextToSpeech.speak() and hearing the audio over the car radio. When I've solved that I'll update this answer.

To reach to any solution for your problem, we must understand first what facility does car audio system provides with bluetooth.
Car audio system support A2DP profile along with HandsFree profile for attaining calls. Now, when bluetooth is selected as the source anything which is played by your app on A2DP profile will be played by audio system. However, once you've switched to other source like radio, even though your device is connected with A2DP profile with car audio system nothing will be played which you are facing now. However, few things that can be tried here, which interrupts the radio play as well are:
We know that when any call comes, we get alert with phone number even when we are listening to radio. This alert portion you can use for your solution. However, I dont know much if we can send phone ring alert from app. These alerts are at lower level just AT commands. Some search would be needed to check this.
In some car audio system, there is facility that when sms comes it alerts you. This alert part can also be explored.
I could see these two option which could help you. But this is not the only option I guess. Please try to find car audio systems bluetooth spec sheet. There you could know what other bluetooth alert features they provide.
I will update this answer I find any hint on my above suggestion.
Thanks

ZXing QR Reader Direct Integration android

Want to develop a QR code reader.. which will customized for my application. after a lot of search i found a link http://www.androidaz.com/development/zxing-qr-reader-direct-integration this tutorial demonstrate what i exactly want. but when i import it and then run this app i notice that its camera is in 90 degree angle when i rotate device. what is the problem i can not realize. my main.xml is
<FrameLayout
android:layout_width="200dip"
android:layout_height="200dip"
android:layout_gravity="center_horizontal">
<include layout="#layout/capture"/>
</FrameLayout>
my mainactivity file is:
public class ScannerActivity extends CaptureActivity
{
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_qrcode);
}
#Override
public void handleDecode(Result rawResult, Bitmap barcode)
{
Toast.makeText(this.getApplicationContext(), "Scanned code " + rawResult.getText(), Toast.LENGTH_LONG).show();
}
}
menifest file with permission :
<uses-permissionandroid:name="android.permission.CAMERA"/>
<uses-permissionandroid:name="android.permission.INTERNET"/>
<uses-permissionandroid:name="android.permission.VIBRATE"/>
<uses-permissionandroid:name="android.permission.FLASHLIGHT"/>
<uses-permissionandroid:name="android.permission.READ_CONTACTS"/>
<uses-permissionandroid:name="com.android.browser.permission.READ_HISTORY_BOOKMARKS"/>
<uses-permissionandroid:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permissionandroid:name="android.permission.CHANGE_WIFI_STATE"/>
<uses-permissionandroid:name="android.permission.ACCESS_WIFI_STATE"/>
it can read QR code fine. only problem camera caused abnormal behavior when rotating..
Thanks in advanced.

Maybe what you would like to do is here:
android-zxinglib
An android library project of zxing BarcodeScanner
https://code.google.com/p/android-zxinglib/
Download the project and look these files:
AndroidManifest.xml
capture.xml

Go into your manifest and change the orientation to landscape. Portrait caused the same problem for me, and landscape looked a lot better.

Android VideoView live tv stream (HLS)

I'am trying to develop app for tv streaming (HLS). Using code below I tested stream on 2.3.3, 3.0 and 4.0.1 version Android devices, but encountered several problems.
On Android 2.3.3 stream plays for >1 minute and then just stops. On Android 3.0 it plays well and on Android 4.0.3 it displays message 'This file cannot be played' (if I remember correctly).
So my question would be:
How can I play stream on ether of these devices, without having stream playing problems? Or where can I read more about solutions to these problems (tried to search but found nothing useful)?
Code in Main_Activity:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
VideoView player = (VideoView)findViewById(R.id.player);
String httpLiveUrl = "http://aj.lsops.net/live/aljazeer_en_high.sdp/playlist.m3u8";
//for Android 2.3.3 I used httplive:// prefix
player.setVideoURI(Uri.parse(httpLiveUrl));
player.setMediaController(new MediaController(this));
player.requestFocus();
player.start();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
Code in xml:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<VideoView
android:id="#+id/player"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true" />
</RelativeLayout>
Sorry if my english is poor.
Thank You.

This will not solve all the streaming issues. But one thing you should do is call player.start() when the MediaPlayer is ready. The selected answer to this SO post sets a listener on the MediaPlayer object so that it will run start() when onPrepared(MediaPlayer mp) is called.

Insert this Code to AndroidManifest.xml
<uses-permission android:name="android.permission.INTERNET" />

Load an SWF into a WebView

I'm having problems with this. If I go to an SWF directly in the browser, it works fine. If I attempt to use loadUrl on an SWF file it stays blank and loads nothing.

Figured it out. You have to enable plugins.
webview.getSettings().setPluginsEnabled(true);

Niky, you have a code example here.
I have used this example to test this code and confirm it works. In this example the qualibus.swf is in contained within the assets of the app. Please test this on an actual device, as on the emulator it show a blank page (probably the flash player is not present on the emulator)
Test3Activity.java:
package com.blabla.test3;
import android.app.Activity;
import android.os.Bundle;
import android.webkit.WebView;
public class Test3Activity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
String url ="file:///android_asset/qualibus.swf";
WebView wv=(WebView) findViewById(R.id.webView1);
wv.getSettings().setPluginsEnabled(true);
wv.loadUrl(url);
}
}
main.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<WebView android:id="#+id/webView1"
android:layout_width="match_parent"
android:layout_height="match_parent">
</WebView>
</LinearLayout>
Result:

The function WebView.getSettings().setPluginsEnabled(); method has
been deprecated since API level 9, and was removed in API level 18.
You can use the newer function
WebView.getSettings().setPluginState(WebSettings.PluginState.ON);
which was added in API level 8 and was deprecated in API level 18.
According to the WebSettings Documentation API levels beyond 18 will
not support plugins; I'm assuming it's because the main plugin to
support was flash which adobe is no longer developing for mobile.
Quoted from source
So, for now you can use it till 18, and handle compatibility with higher APIs (sadly)