Develop Reference

Fragment webView for Button (to call or dial a number) [Android Studio]

I have successfully added a WebView to a fragment, to load a website. However, some elements on the website, such as a button, link to a tel= scheme, resulting in an err_unknown_url_scheme error when pressed. How can I support this?
This is my code:
fragment_notification.xml
android:layout_width="match_parent"
android:layout_height="match_parent">
<WebView
android:layout_width="match_parent"
android:id="#+id/webView3"
android:layout_height="match_parent">
</WebView>
NotificationsFragment.java
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import androidx.annotation.NonNull;
import androidx.fragment.app.Fragment;
import com.alidmisli.gcsdriver.R;
public class NotificationsFragment extends Fragment {
public NotificationsFragment() {
}
public View onCreateView(#NonNull LayoutInflater inflater,
ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_notifications, container, false );
WebView webView= (WebView)v.findViewById(R.id.webView3);
webView.getSettings().setJavaScriptEnabled(true);
webView.setWebViewClient(new WebViewClient());
webView.loadUrl("http://gcs-bn.com/sos.html/");
return v;
}
}
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.alidmisli.gcsdriver">
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
<uses-permission android:name="android.permission.CALL_PHONE" />
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity
android:name=".MainActivity"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

Set webviewclient like this
webView.setWebViewClient(new CustomWebViewClient());
String TELPREFIX = "tel:"
class CustomWebViewClient extends WebViewClient {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
if(url.startsWith(TELPREFIX)) {
Intent intent = new Intent(Intent.ACTION_DIAL);
intent.setData(Uri.parse(url));
startActivity(intent);
return true;
}
return super.shouldOverrideUrlLoading(view, url);
}
}

".MainActivity" in <activity android:name=".MainActivity"> is not a concrete class

When inspecting my code, I get an error in the AndroindManifest.xml saying that
".MainActivity" in <activity android:name=".MainActivity"> is not a concrete class.
The App is, therefore, crashing in the Emulator of Android Studio.
Here is the Java Code of the Application:
package de.thi.donotpressthebutton;
import android.media.MediaPlayer;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity {
Button button;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button = (Button) findViewById(R.id.button);
final MediaPlayer audio = MediaPlayer.create(this, R.raw.niggaz_audio );
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
audio.start();
}
});
}
}
And here is the XML Code:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="de.thi.donotpressthebutton">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".MainActivity"> **//error**
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

If your mainactivity.java is not in the package root directory, you should add the folder name. For example, mainactivity.java in the com.balbala.holleworld/View/folder should be <activity android:name=".view.MainActivity"> instead of <activity android:name=".view.MainActivity">. Hope to solve your problem.

The other Reason For this Type Of Error Might Be That You Have Accidentally Used "Abstract"
Keyword Before the Activity Name That Might Have Caused The Problem In The Project

how to mopub ads add in application

i want to add ads banner in my application i have integrate mopub sdk with my project and import and add library to the my project now my question is how to add banner disply and where code i have to write in my application java code and xml code about ads so please help enyone
my java code and mainifest file code is given below
mainactivity.java
package com.example.ration;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.os.Build;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.Toast;
public class MainActivity extends Activity {
private WebView web;
int k;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
web=(WebView)findViewById(R.id.web);
web.getSettings().setJavaScriptEnabled(true);
web.setWebViewClient(new WebViewClient());
web.getSettings().setBuiltInZoomControls(true);
web.loadUrl("http://dcs-dof.gujarat.gov.in/live-info.htm");
// web.getProgress();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
menu.add(0,1,menu.NONE,"About");
menu.add(0,2,menu.NONE,"Feedback");
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id=item.getItemId();
if(id == 1)
{
Toast.makeText(MainActivity.this,"About",Toast.LENGTH_LONG).show();
Intent i=new Intent(MainActivity.this,about.class);
startActivity(i);
}
else {
Toast.makeText(MainActivity.this,"Feedback",Toast.LENGTH_LONG).show();
Intent i2 =new Intent(MainActivity.this,feedback.class);
startActivity(i2);
}
return super.onOptionsItemSelected(item);
}
private boolean doubleBackToExitPressedOnce = false;
#Override
protected void onResume() {
super.onResume();
// .... other stuff in my onResume ....
this.doubleBackToExitPressedOnce = false;
}
#Override
public void onBackPressed() {
if (doubleBackToExitPressedOnce) {
super.onBackPressed();
return;
}
this.doubleBackToExitPressedOnce = true;
Toast.makeText(this,"Press Again to Exit", Toast.LENGTH_SHORT).show();
}
}
and my manifest file is
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.ration"
android:versionCode="1"
android:versionName="1.0" >
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="18" />
<application
android:allowBackup="true"
android:icon="#drawable/icon"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.example.ration.MainActivity"
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.ration.about"></activity>
<activity android:name="com.example.ration.feedback"></activity>
<activity android:name="com.mopub.mobileads.MoPubActivity" android:configChanges="keyboardHidden|orientation"/>
<activity android:name="com.mopub.mobileads.MraidActivity" android:configChanges="keyboardHidden|orientation"/>
<activity android:name="com.mopub.mobileads.MraidBrowser" android:configChanges="keyboardHidden|orientation"/>
<activity android:name="com.mopub.mobileads.MraidVideoPlayerActivity" android:configChanges="keyboardHidden|orientation"/>
<activity android:name="com.google.ads.AdActivity" android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize" />
<activity android:name="com.millennialmedia.android.MMActivity" android:theme="#android:style/Theme.Translucent.NoTitleBar" android:configChanges="keyboardHidden|orientation|keyboard" />
<activity android:name="com.millennialmedia.android.VideoPlayer" android:configChanges="keyboardHidden|orientation|keyboard" />
</application>
</manifest>

I think you should better go through the guide for Mopub Banner Ads Integration which explains you the steps of banner ads integration.
Hope this will help you.

Use view in XML file
<com.mopub.mobileads.MoPubView
android:id="#+id/mrect_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center_horizontal"
android:layout_weight="1" />
in activity Load code
pass id of view in below function ,unit id of ur app,and keywords of cataogry of ads
public void loadMoPubView(MoPubView moPubView, String adUnitId, String keywords) {
if (moPubView == null) {
Utils.logToast(LockScreenActivity.this, "Unable to inflate MoPubView from xml.");
//Toast.makeText(this, "Unable to inflate MoPubView from xml.", Toast.LENGTH_SHORT).show();
return;
}
try {
Utils.validateAdUnitId(adUnitId);
} catch (IllegalArgumentException exception) {
Utils.logToast(LockScreenActivity.this, exception.getMessage());
return;
}
moPubView.setBannerAdListener(this);
moPubView.setAdUnitId(adUnitId);
moPubView.setKeywords(keywords);
moPubView.setAutorefreshEnabled(true);
moPubView.loadAd();
}

application runs but no app icon in emulator

In my code I have a webview. the code runs and shows the web content.But after pressing the backward key in emulator i can not see the app icon in it for reopening. the logcat shows the following error also
WebActivity.java
package example.webapp;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
public class WebActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_web);
WebView mainWebView = (WebView) findViewById(R.id.mainWebView);
WebSettings webSettings = mainWebView.getSettings();
webSettings.setJavaScriptEnabled(true);
mainWebView.setWebViewClient(new MyCustomWebViewClient());
mainWebView.loadUrl("http://google.com");
mainWebView.setScrollBarStyle(View.SCROLLBARS_INSIDE_OVERLAY);
}
private class MyCustomWebViewClient extends WebViewClient {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(url);
return true;
}
}
}
logcat
08-22 17:53:11.464: E/geolocationService(278): Caught security exception registering for location updates from system. This should only happen in DumpRenderTree. please give me an answer
manifest file
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="example.webapp"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="8" />
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="example.webapp.WebActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

Android SecurityException ACCESS_WIFI_STATE

I am building an Android app that uses wifi.
I have properly declared these uses permissions in the manifest, however for some reason the app is throwing a SecurityException that causes the app to force-close.
I traced the cause of the security exception in LogCat to the system saying it doesn't have the access_wifi_state permission. This is strange and confusing to me because I have already declared it in the manifest.
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="android.wifi"
android:versionCode="1"
android:versionName="1.0" >
<uses-permission android:name="ACCESS_WIFI_STATE" />
<uses-permission android:name="CHANGE_WIFI_STATE" />
<uses-feature android:name="android.hardware.wifi" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-sdk android:minSdkVersion="8" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name" >
<activity
android:name="android.wifi.AndroidWiFiActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
And here is the code that causes the exception:
package android.wifi;
import android.app.Activity;
import android.content.Context;
import android.net.wifi.WifiManager;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.widget.Button;
import android.widget.TextView;
import android.wifi.R;
public class AndroidWiFiActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
TextView tv = (TextView) findViewById(R.id.textbox);
tv.setText("ABC 123");
WifiManager wifiMgr = (WifiManager) getSystemService(Context.WIFI_SERVICE);
if(wifiMgr.isWifiEnabled())
{
tv.append("Wifi is enabled");
}
else
{
tv.append("Wifi is disabled");
}
}
}
Any help is greatly appreciated. Thanks.

The permission is:
android.permission.ACCESS_WIFI_STATE