Develop Reference

How do I trigger a button in an html page, from my android app?

I am working on a simple Home Automation project, using Raspberry Pi3. The basic idea is to have an Android app which can switch on/off an electric bulb. I have created a simple HTML web page which runs a python script to turn on/off the connected relay to the light bulb, whenever I press the corresponding buttons on the web page.
What i want to achieve is to have the buttons on the web page somehow toggled from buttons on a simple Android app.
Please understand that I am almost entirely new to app development and have no interests in further pursuing it. So I am looking for some workaround maybe, or a quick solution that helps me use my already functional web page, just from a simple android app. I would be able to implement the development part, hopefully, if I can get an idea of what exactly do I have to develop for achieving the above mentioned functionality.

Working with webform delphi xe7 fmx

I'm using webform from Rest.Authenticator.OAuth.Webform.Fmx to get access to one of the google api. This mechanism is working on my desktop app, so I want to use it on android app. But there is a trouble: I can't copy access code, from Twebbrowser on webform. Android does not raise mechanism of copying text.
What is the right way to solve this problem?
Parse page from webbrowser?

Well, I found the solution, the token i need will be here:
webform.lasttitle
After changing this title I will copy it and close webform automatically.

move existing web app into a native phone app using a browser wrapper

So lets say there is a fully functional responsive ruby rails web app. This app works and looks great on mobile phones. Unfortunately, this web app can't be seen from the mobile phone app stores, because it's not a native app. Technically you could place an icon on a smart phone that opens up the browser, but obviously this is not optimal.
Is there a way to create a native app (Android, iPhone) that is essentially just a browser, without the navigation bar? This browser's wrapper would just load the web app and behave just like you had opened up the browser.
I have looked into options such as Phonegap and Titanium, but it seems there would be a significant amount of rewriting, and there are very little funds for this.

I don't really know iOS, but doing it in Android will be really easy.
First, this is your activity:
package com.example.my_browser;
import android.app.Activity;
import android.os.Bundle;
import android.webkit.WebView;
public class MyActivity extends Activity {
/**
* Called when the activity is first created.
*/
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
WebView browser = (WebView)findViewById(R.id.browser);
browser.loadUrl("http://google.com"); //Replace google.com with you webapp's URL
}
}
This is your main.xml layout:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<WebView
android:id="#+id/browser"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
</LinearLayout>
And you will need to request internet permission in AndroidManifest.xml:
<uses-permission android:name="android.permission.INTERNET" />
I just tested this in an emulator and it works.

This answer is for iOS.
You can have an icon of your website on the home screen of the device without writing a line of code (no UIWebView, no native coding, no XCode).
Download iPhone Configuration Utility from http://www.apple.com/support/iphone/enterprise/
Start iPhone Configuration Utility and from the left menu select "Configuration Profiles"
In the General section of your new profile fill out the Name (MyWebsite app) and identifier (com.mycompany.coolapp). You can add also organization name and description.
Scroll down and select Web Clips section.
In the Label field you can enter the name that will be visible on the home screen.
URL will be the URL of your web site / web app.
Select the icon to be used as a home screen icon. Use at least 114x114 pixel resolution.
If you select "Full screen", the navigation bar and the address bar of Safari will be hidden when you launch your web app, so you can have a real "app".
Click on the "Export" button. You can decide whether to sign your profile (will be visible by the end user when he installs your profile).
Save the .mobileconfig file and upload it to your web server or send to your end users via mail.
When the end user opens the .mobileconfig file on his device, the system will ask him to install the configuration profile. After the installation a home screen icon will be created that points to your web site.
Update as of 2017
iPhone Configuration Utility has been replaced by Apple Configurator that you can download free from App Store. You can create a new Configuration Profile the same way as described for Apple Configurator, selecting File -> New Profile in the app.

edit 2
As #MrTJ said in the comments. Apparently Apple won't let you have a simple "website wrapper" application. So your only options would be porting Ruby, like the rest of my answer describes, porting the application natively, or doing a web app like #MrTJ describes in his answer. Porting it natively, supported by RESTlike web services, would probably be the best solution. Web Apps are nice, but native applications are usually nicer. It depends on what kind of user experience you want to provide.
end edit 2
edit 1
I need to read more carefully. I answered your question assuming you wanted to embed the application, without needing to access the internet. If that is NOT what you are trying to do, then it is definitely possible.
Just make an application that has a webview and loads the base URL for the site. You will probably want to do a special version of the site that ALWAYS has back buttons etc, so the user can never get stuck in a corner of your site (since you want the navbar hidden).
Also, personally I would not do this, you can, but you probably shouldn't. You will need to handle what to do when the user does not have an internet connection. And you may make them less than happy when they (potentially) paid for an application that they can't use everywhere. Native Applications tend to sell/perform much better.
end edit 1
My Personal Reaction to This Question
Cool Question. Personally I am not a fan or Ruby or Rails (I'm a bit more of a Python guy, but Python is actually why I know anything about this situation), but this is a pretty cool problem regardless.
Questions to ask yourself
Is this possible? Probably
Is it a good idea? Probably Not
Is it going to be worth the effort? Probably Not
And most importantly, will Apple let you sell it? ....Maybe, but for something like this, you won't know till you try....
What you Need
A WebView that uses a protocol to talk to your native application. This would be like the URL hash tag hack used to talk to an iFrame in a browser, or the protocol that PhoneGap uses to communicate with it's WebView
Embedded version of the Ruby Interpreter. People have been doing this on iOS with both the Python and JavascriptCore interpreters. Some people will try to tell you Apple won't let you do this, but that is no longer true. You will need to compile Ruby specifically for iOS, this will probably be annoying, but I bet if you base your implementation on the Python/Javascript implementations, you could eventually get it working.
edit
Another SO question/answer with relevance to this answer
Embed a JavaScript engine in an iOS application
end edit
Embedded version of Rails... Good luck :)
Method of triggering the Rails app without a web server (you probably can't run apache locally on an iPhone (would be difficult and would probably crash immediately), and definitely not on Android). You will either need to trigger each view manually somehow, piping the output to either a string or a file, and load that string (HTML) or file into the WebView
Method of triggering navigation in the Rails application. This will require catching link presses from the WebView (you can watch for the URL changing on iOS), and triggering the proper Rails view to produce its HTML.
Problems
Ruby and Rails are both VERY HEAVY. Most implementations I have seen require at least 256mb of RAM, iOS will instantly kill your application if it tries using this much memory at startup. Android will probably handle it far less gracefully and just crash unexpectedly at some point in the application run.
Android does not run Native Compiled code. This means you will need to run JRuby, which will leave you with an interpreted language running in an interpreted language (read as, Slow As Hell On a Mobile Device).
This will require writing MORE Ruby, some Javascript, and MORE Java or Objective-C. So in other words, Don't. Figure out what your application does, and port it.
Key Learning
This is will probably take way more effort than any sane developer would ever want to spend on a 'simple web application'. You will be far better off learning Native development, since that will be required to get this job done anyway.

Yes, for iOS simply load a UIWebView fullscreen and change the UIWebView's current URL to whatever the location of your web-app is. launching UIWebview with specific url
I don't know anything about android but apparently it's the same process... Here ya go: How to set url on WebView from a xml layout file on Android?
To communicate between iOS app and your website you can use stringByEvaluatingJavaScriptFromString mentioned here: Passing Javascript Variable to Objective-C
To do this with Android refer to the other answers to this question where they have already listed the code in their answer.

Easiest way to launch webpage in android with an icon

We have a website that offers an e-mail service. We would like to create a fully fledged app for this but cannot afford this right now. In the mean time it would be great if we could give users an icon on their phones that will take them to a page formatted for mobile on the internet. So what I'd like to know is how can we get an icon on an android users phone that will simply launch a web link in a browser- does this have to be an app, is there an easier way, or am I over estimating how complicated it would be to make this as an app anyway?
Thanks in advance

Create a new Android project (after following the SDK installation steps provided at http://developer.android.com)
on the directory /res/drawable-*dpi you have the laucher icons. Modify all of them.
In the main activity, delete all inside the onCreate method an put this:
String url = "http://www.YOUR-URL.com";
Intent i = new Intent(Intent.ACTION_VIEW);
i.setData(Uri.parse(url));
startActivity(i);
This will open the android browser with the URL provided.

I have done projects like this in the past, it is very simple. You need to create a website formatted for a smaller screen. Once you do this, building an android app that displays your website inside it is simple. You can even remove all of the android browser toolbars so it appears as if your website is a real android application. Google android webviews, this will point you in the right direction.

See here for what's probably the best instruction page on how to do exactly that:
http://intelnav.50webs.com/app_project.html
It's based on a Webview, that is it opens the page and does all the navigation in the app window, not in the default browser. So if you want to open it in the browser, you have to use Intent, as said in previous answers.
My 2 pennies worth, I think it's better in the app window unless you really want complex navigation with the possibility of opening additional tabs, windows and so on. The drawback with the external browser is that, as far as I could see, there's no way to tell if the page is already open in the browser so you'll launch a different copy (in a new tab) every time. If the user doesn't close the tab at the end, they usually don't, it can become quite annoying. Besides, within an app you'll probably have somewhat better possibilities for ads should you ever want them.
Versus a simple home-screen bookmark, as others pointed out, it's simpler and more convenient for end users to just download an app from an online store (usually Google Play). It's what they're used to do. And they do have a lot of additional info available, like what it does, what others say about it, screen shots (if you provide some for them but you should). Plus a way to comment / complain themselves. It's a different thing. Technically it may not make a lot of sense but from a simple user's perspective it's clearly better IMO.

One way is to bookmark the site and then add it to your home screen. Source

It seems to me like you need a mobile version of your web page. Do you have that already? Once you have your mobile website (ie. website optimized for mobile devices), you could create a simple application with only one WebView. All content would be fetched from your site and displayed inside a webview. This is trivial to make, however, making an entire mobile website will take some time.
Note that you do not HAVE TO have a mobile website, you could pack you existing website into a WebView, but this would lower user experience.

you would build an app that launches a browser intent linking to your website, or a custom WebView to launch your website in full screen without any navigation bar etc..

The only easier way is to put instructions on your site (directly, or as a contextual pop-up) on how to add the bookmark as an icon on your home screen. This can be slightly more complicated on Android, and depends on the browser. A simpler option for your potential users is to provide a wrapper app via the Marketplace.
It is not overly complicated to create a simple wrapper Android app in Java that launches the browser, using Intents. The essential browser launch code is basically this:
Uri uriUrl = Uri.parse("http://www.yourwebpage.com");
Intent launchBrowser = new Intent(Intent.ACTION_VIEW, uriUrl);
startActivity(launchBrowser);
A more detailed tutorial for creating this is available here:
http://mobile.tutsplus.com/tutorials/android/launch-android-browser/

Try this kick-start mobile device app for showing websites. Written with cordova for platforms like android, ios, browser and so on: https://github.com/jetedonner/ch.kimhauser.cordova.kickstartwebsite (GooglePlay: https://play.google.com/store/apps/details?id=ch.kimhauser.cordova.kickstartwebsite, Website: http://kimhauser.ch/index.php/projects/cordova-phonegap/kick-start-website)

Android: How to use a Android Pad as a customer information Terminal

I want to us an Android-powered Pad as an information terminal for my customers.
The only thing it has to to is to show a HTML5 Webpage.
Therefore,
1. it should not be posiible to show another website (only the local one), should be no problem
it should be only possible to leave the app with a password (how?)
and all buttons should be disabled (that´s hard).
I found out how to set the target for the home button, but maybe there is an existing solution.
Thanks
Christian

I assume you understand the easiest way to do this is to develop an Android native application to show your webpage. This is done by using a WebView, but the support of HTML5 depends on the platform, so if you use any video or audio, you may need some hooks.
Trhough a WebView, you can filter which urls can be opened or not.
And well, I don't think there are many problems on exiting only when a password is entered.
Regarding to number 2, AFAIK, you can let your Activity ("window" of the application) to handle most of keys, but obviously you can't map the power key.
But I have to confess, when you develop an application, you always find some issues... so probably is not that easy as I wrote in these lines... Good luck!