Develop Reference

Getting troubles making status bar hovering the activity

I have a web site, and I decided to make an Android application for it, but I actually write under win32 on c++, and have never programming under Android. So I decided to make just a Blink render instance, fit it the screen size in my app and load automatically my site. Also I want the status bar hovering on the "activity", searched the internet but can't do this, so please point me, where am I wrong. Stuff should work from Android 4.4 and above. Working in Android Studio
What do I have now:
What do I want to:
My code:
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.myapplication">
<uses-permission android:name="android.permission.INTERNET" />
<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">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"
android:fitsSystemWindows="true">
<WebView
android:id="#+id/webview"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
/>
styles.xml
<resources>
<!-- Base application theme. -->
<style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
<!-- Customize your theme here. -->
<item name="colorPrimary">#000000</item>
<item name="colorPrimaryDark">#color/colorPrimaryDark</item>
<item name="colorAccent">#color/colorAccent</item>
<item name="android:windowTranslucentStatus">true</item>
</style>
MainActivity.java
package com.example.myapplication;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE|View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
WebView myWebView = findViewById(R.id.webview);
myWebView.setWebViewClient(new WebViewClient());
myWebView.loadUrl("http://somesite.com");
WebSettings webSettings = myWebView.getSettings();
webSettings.setJavaScriptEnabled(true);
}
}

Try this on onCreate this will make both transparent
getWindow().setFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS,WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);
or try
getWindow().setFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION,WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS,WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);

Add progress bar on top of your webview
<ProgressBar android:id="#+id/pB1"
style="?android:attr/progressBarStyleHorizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:padding="2dip">
</ProgressBar>
And then you need to set progress status on the progressbar like this:
myWebView.setWebChromeClient(new WebChromeClient() {
public void onProgressChanged(WebView view, int progress) {
if(progress < 100 && pbar.getVisibility() == ProgressBar.GONE){
pbar.setVisibility(ProgressBar.VISIBLE);
}
pbar.setProgress(progress);
if(progress == 100) {
pbar.setVisibility(ProgressBar.GONE);
}
}
});

Error inflating class fragment. Must specify unique android:id, android:tag, or have a parent with an id

I am trying to run a fragment but my application keeps on crashing when i run it. I am trying to load the main activity so that i can display the webview in it but i am having no luck.
MainActivity
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
public class MainActivity extends FragmentActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
}
Fragment code
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebSettings;
import android.webkit.WebView;
public class WebViewFragment extends Fragment {
private WebView mWebView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_main, container, false);
mWebView = (WebView) view.findViewById(R.id.webView);
WebSettings webSettings = mWebView.getSettings();
webSettings.setJavaScriptEnabled(true);
mWebView.loadUrl("https://www.google.co.uk/");
return view;
}
}
Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.bashirsentongo.webviewapp">
<uses-permission android:name="android.permission.INTERNET"/>
<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>
</application>
</manifest>
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<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"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.bashirsentongo.webviewapp.MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World!" />
<fragment
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
class="com.example.bashirsentongo.webviewapp.WebViewFragment"/>
</RelativeLayout>
fragment_main.xml
<FrameLayout 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="layout.main">
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="#string/hello_blank_fragment" />
<WebView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/webView"/>
/>
</FrameLayout>

From the official documentation:
Note: Each fragment requires a unique identifier that the system can use to restore the fragment if the activity is restarted (and which you can use to capture the fragment to perform transactions, such as remove it). There are three ways to provide an ID for a fragment:
Supply the android:id attribute with a unique ID.
Supply the android:tag attribute with a unique string.
If you provide neither of the previous two, the system uses the ID of the container view.
https://developer.android.com/guide/components/fragments.html
Also you find an example here using an id for the fragment:
<fragment android:name="com.example.news.ArticleListFragment"
android:id="#+id/list"
android:layout_weight="1"
android:layout_width="0dp"
android:layout_height="match_parent" />

You seem to be confused with how to implement a Fragment.
The Fragment is loaded onto a viewgroup (typically FrameLayout) contained within the Activity, there isn't really a need for the Fragment to have a FrameLayout in your case. (Because the TextView and Webview will overlap)
That being said, once you have a FrameLayout in place of the use of the <fragment> tag, think about, how would you load the Fragment in the Activity? A FragmentTransaction. What does that need? An id for the view container to load the Fragment. And that's your error - you don't have one.

All of your <fragment> containers should have unique ID. Then just set ID for root RelativeLayout.

Pass data between two activities in android

I made an android app which passes data between two activities but an error occurs in my code that I can't discover.
First "activity_main.xml" executes, and when the user presses a button, a second activity "activity_main1.xml" starts. But when the button is pressed, an error occurs and app stops.
This is the MainActivity.java:
package com.example.measureregistertool;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void sendMessage(View view) {
Intent intent = new Intent(MainActivity.this, MainActivity1.class);
startActivity(intent);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
This is the activity_main.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"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="90dp"
android:onClick="sendMessage"
android:text="Take Photo" />
</RelativeLayout>
This is the activity_main1.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="New Activity" />
</LinearLayout>
This is the manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.measureregistertool"
android:versionCode="1"
android:versionName="1.0" >
<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.measureregistertool.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>
My code error

Your second activity is missing in the manifest file. You probably created it just by creating new java class, not by creator from right click.
Add it to the manifest below your activity tag
<activity
android:name="com.example.measureregistertool.MainActivity1">
</activity>

You have two activities in your package,But have only declared one in manifest.
Declare the other Activity class.

You need to add the second Activity (MainActivity1) in your AndroidManifest.xml
<activity
android:name="com.example.measureregistertool.MainActivity1"
android:label="#string/app_name" >
</activity>

Always create activity by File->new->Activity -> (Select Category).
This process performs three operations
1. Create Activity java file.
2. Create Layout xml file.
3. Register your Activity class in Manifest file.
So you can be safe from such problems.

Android layout xml file not running

Below is a code for layout main.xml file
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/button" />
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/button" />
</LinearLayout>
Here is the activity file
package alvisoft.helloworld;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.MenuItem;
import android.support.v4.app.NavUtils;
public class MainActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
but when I run it on eclipse with android SDK it shows blank screen instead of showing button and textview.I am absolute beginner and don't know what's the problem Kindly Help me!

I also make mistakes like you. You can fix this error as follows:
- On the tab Graphic_layout you drag and drop layout LinearLayout(on the left) into the interfaces.
- Then on the tab main.xml You created newly code into this LinearLayout. This error has been fixed.

i think you forgot to add your activity in AndroidManifest.xml.
update your manifest file like this.
<?xml version="1.0" encoding="utf-8"?>
<manifest package="app.sample" android:versionCode="1"
android:versionName="1.0" xmlns:android="http://schemas.android.com/apk/res/android">
<application android:icon="#drawable/icon" android:label="#string/app_name"
android:theme="#android:style/Theme.Light.NoTitleBar.Fullscreen">
<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>
i tried your code. it is working fine. but the R.menu.main file was missing. i removed the options menu and tried

Starting activities with intents in Android - why does this work?

Previously I've been looking at existing code to display a map in a tab, and this time I've tried to write it myself to see if I understood it.
It runs fine without errors (screenshot), but I don't completely understand why, and whether I'm doing this in the best way.
The part that I don't quite understand is in the manifest.
I would have thought that android:label should be maptabview_name, but that gives me an error saying no matching resource was found.
Why does it run when using app_name for that activity?
Why can't it find the maptabview_name resource?
Also, in MapTab2, is this the best way to start an intent?
What exactly is this telling the system? "I intend to start an activity from this class"?
Here's my code
(It's based on this):
MapTab2.java
package com.test.maptab2;
import android.app.TabActivity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TabHost;
public class MapTab2 extends TabActivity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Intent i = new Intent(this,MapTabView.class);
TabHost.TabSpec spec;
spec = getTabHost().newTabSpec("tab1");
spec.setContent(i);
spec.setIndicator("Map");
getTabHost().addTab(spec);
spec = getTabHost().newTabSpec("tab2");
spec.setContent(R.id.detailstub);
spec.setIndicator("Detail");
getTabHost().addTab(spec);
getTabHost().setCurrentTab(0);
}
}
MapTabView.java
package com.test.maptab2;
import android.os.Bundle;
import com.google.android.maps.MapActivity;
public class MapTabView extends MapActivity {
#Override
public void onCreate (Bundle icicle){
super.onCreate(icicle);
setContentView(R.layout.maptabview);
}
#Override
public boolean isRouteDisplayed(){
return false;
}
}
Main.xml
<?xml version="1.0" encoding="utf-8"?>
<TabHost xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#android:id/tabhost"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
<!-- Tab-switch panel -->
<TabWidget android:id="#android:id/tabs"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
<!-- Tab contents -->
<FrameLayout android:id="#android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<!-- Map here -->
<RelativeLayout android:id="#+id/mapstub"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"/>
<!-- Other stuff -->
<TextView android:id="#+id/detailstub"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="detail"/>
</FrameLayout>
</LinearLayout>
</TabHost>
maptabview.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/maptablayout"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<com.google.android.maps.MapView android:id="#+id/mapview"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:clickable="true"
android:apiKey="0HRMcD5o6WrBVhmwbWpeyeavZ67PXWOvJeeCx2g"/>
</RelativeLayout>
MapTab2.Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.test.maptab2"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="3" />
<uses-permission android:name="android.permission.INTERNET" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name" >
<uses-library android:name="com.google.android.maps" />
<!-- Main -->
<activity android:name=".MapTab2"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<!-- Map -->
<activity android:name=".MapTabView"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.EMBED" />
</intent-filter>
</activity>
</application>
</manifest>

Q1: maptabview_name has to be in a string resource file, usually at res/values/string.xml, in case you have it there and still it's not in the resources generated file (gen/package/R.java), try removing it and let eclipse generate it again.
Q2: AFAIK, TabHost.TabSpec.setContent(Intent intent) it's like starting the Activity within the specified tab. I think that's the way do do it when you deal with tabs. Since Intents are used to do a lot of things, this is a basic usage, in this case just to specify the class.