I'm trying to start an activity from a javascript interface in my webview.
The example shows a toast. How could i call a class instead of a toast?
public class JavaScriptInterface {
Context mContext;
/** Instantiate the interface and set the context */
JavaScriptInterface(Context c) {
mContext = c;
}
/** Show a toast from the web page */
public void showToast(String toast) {
Toast.makeText(mContext, toast, Toast.LENGTH_SHORT).show();
}
}
this for the html page.
<input type="button" value="Say hello" onClick="showAndroidToast('Hello Android!')" />
<script type="text/javascript">
function showAndroidToast(toast) {
Android.showToast(toast);
}
You have to first register the JavaScriptInterface on your webview.
JavaScriptInterFace can be a inner class as shown below. This class will have a function that you can call from html page( via javaScript ) and inside this function you can write code to change activity.
Here is the working solution for you:
public class JavascriptInterfaceActivity extends Activity {
/** Called when the activity is first created. */
WebView wv;
JavaScriptInterface JSInterface;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
wv = (WebView)findViewById(R.id.webView1);
wv.getSettings().setJavaScriptEnabled(true);
// register class containing methods to be exposed to JavaScript
JSInterface = new JavaScriptInterface(this);
wv.addJavascriptInterface(JSInterface, "JSInterface");
wv.loadUrl("file:///android_asset/myPage.html");
}
public class JavaScriptInterface {
Context mContext;
/** Instantiate the interface and set the context */
JavaScriptInterface(Context c) {
mContext = c;
}
#android.webkit.JavascriptInterface
public void changeActivity()
{
Intent i = new Intent(JavascriptInterfaceActivity.this, nextActivity.class);
startActivity(i);
finish();
}
}
}
Here is the html page
<html>
<head>
<script type="text/javascript">
function displaymessage()
{
JSInterface.changeActivity();
}
</script>
</head>
<body>
<form>
<input type="button" value="Click me!" onclick="displaymessage()" />
</form>
</body>
</html>
Hope this helps...
You also need to add the #android.webkit.JavascriptInterface annotation on top of your changeActivity method in your android code, should you run on Android 4.2 or higher.
See this link for more.
Related
I am trying to implement a simple callback to call a function from Java to WebView. I successfully called the function from Javascript to Java but couldn't get any success for the otherway around.
Here's my MainActivity.java
public class MainActivity extends AppCompatActivity {
WebView view;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
view= new WebView(this);
setContentView(view);
view.loadUrl("file:///android_res/raw/meter.html");
view.getSettings().setJavaScriptEnabled(true);
view.addJavascriptInterface(new WebAppInterface(this), "Android");
}
public class WebAppInterface {
Context mContext;
/** Instantiate the interface and set the context */
WebAppInterface(Context c) {
mContext = c;
}
/** Show a toast from the web page */
#JavascriptInterface
public void register(String callback) {
Log.e("work","log printing"); // <--- coming here
view.loadUrl("javascript:callbacker('hola moma');");
}
/** Show a toast from the web page */
#JavascriptInterface
public void showToast(String toast) {
Toast.makeText(mContext, toast, Toast.LENGTH_SHORT).show();
}
}
}
And here's my meter.html file
<script type="text/javascript">
function showAndroidToast(toast) {
Android.register("callbacker");
}
function callbacker(data){
Android.showToast(data);
}
</script>
</head>
<body>
<p>Display a gauge:</p>
<meter value="2" min="0" max="10">2 out of 10</meter><br>
<meter value="0.6">60%</meter>
<input type="button" value="Say hello" onClick="showAndroidToast('Hello Android!')" />
<p><strong>Note:</strong> The <meter> tag is not supported in Internet Explorer, Edge 12, Safari 5 and earlier versions.</p>
</body>
Now When I run the application the Log in the register function of MainActivity.java is printed. But the next line is which is just a call to the callback function is not called. What could be the problem ?
I am using following code.
Android Code
myBrowser.getSettings().setJavaScriptEnabled(true);
myBrowser.loadUrl("file:///android_asset/mypage.html");
myBrowser.setWebViewClient(new WebViewClient());
myBrowser.addJavascriptInterface(new MyJavaScriptInterface(MainActivity.this), "MyJavaScriptInterface");
public class MyJavaScriptInterface {
MainActivity mContext;
MyJavaScriptInterface(MainActivity c) {
mContext = c;
}
public void showToast(String toast)throws NoSuchFieldException, IllegalArgumentException, IllegalAccessException{
Log.e("inside","showtoast of myjavascript interface");
Toast.makeText(mContext, toast, Toast.LENGTH_SHORT).show();
}
}
JavaScript Code
<input type="button" value="Open Dialog" onClick="checkWindow()"/>
<script language="javascript">
function checkWindow(){
console.log("andriod obj"+window.MyJavaScriptInterface);
if(window.MyJavaScriptInterface){
console.log("andriod in methd"+window.MyJavaScriptInterface);
window.MyJavaScriptInterface.showToast('Hii...');
}
}
</script>
When I click on open dialog button, I get error as "Uncaught TypeError: window.MyJavaScriptInterface.showToast is not a function",
Please tell me what am I missing
I am trying to open android activity on html button click. This is not happening properly. I was using JavaScript for that.which is not working. My javascript is not getting called.
public class WebViewActivity extends CordovaActivity{
JavaScriptInterface JSInterface;
#SuppressLint("SetJavaScriptEnabled")
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
super.init();
setContentView(R.layout.webview);
WebView wV = (WebView)appView.getEngine().getView();
wV = (WebView) findViewById(R.id.webView1);
wV.addJavascriptInterface(new JavaScriptInterface(this), "JSInterface");
System.out.println("Opening webview");
wV.loadUrl("file:///android_asset/index.html" ); }
public class JavaScriptInterface {
Context mContext;
/** Instantiate the interface and set the context */
JavaScriptInterface(Context c) {
mContext = c;
}
public void changeActivity()
{
Log.d("In webviewActivity", "Inside change activity");
Intent i = new Intent(WebViewActivity.this, Google.class);
startActivity(i);
Log.d("After Intent", "Opening google class");
finish();
}
}
}
This is my html file from where my javascript calls inner class method
index.html
<!DOCTYPE html>
<html>
<body>
<head>
<script>
function myFunction() {
alert("Hiii");
JSInterface.changeActivity();
}
</script>
</head>
<button onclick="myFunction()">Try it</button>
</body>
</html>
I have use this code:
JavaScriptInterface jsInterface = new JavaScriptInterface(this);
webView.getSettings().setJavaScriptEnabled(true);
webView.addJavascriptInterface(jsInterface, "JSInterface");
class
JavaScriptInterface:
public class JavaScriptInterface {
private Activity activity;
public JavaScriptInterface(Activity activiy) {
this.activity = activiy;
}
public void startVideo(String videoAddress){
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.parse(videoAddress), "video/3gpp");
activity.startActivity(intent);
}
}
and js:
<a href='' onclick="window.JSInterface.startVideo('Environment.getExternalStorageDirectory()+File.separator+"Application"+File.separator+test.3gp');" >play
</a>
but i am not able to locate the file.
any one have working code for target version below 15.
please post..
thanks in advance.
I have already found many examples about how to call JavaScript from android. But it's not working for me. My target SDK is 17(android 4.2). This is how I am loading my html page from my activity:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_test);
myWebView = (WebView)findViewById(R.id.mapwebview1);
WebSettings webSettings = myWebView.getSettings();
webSettings.setJavaScriptEnabled(true);
JavaScriptHandler jScriptHandler = new JavaScriptHandler(this);
WebChromeClient myWebChromeClient = new WebChromeClient();
myWebView.setWebChromeClient(myWebChromeClient);
myWebView.addJavascriptInterface(jScriptHandler, "MyHandler");
myWebView.loadUrl("file:///android_asset/mywebpage.html");
myWebView.loadUrl("javascript:myFunc()");
}
Here is the code for my JavaScriptHandler:
public class JavaScriptHandler {
//TabFragmentMap mapFragment;
Context context;
//Fragment fragment;
public JavaScriptHandler (Context c){
this.context = c;
}
}
Here is the code for my html:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>PhoneGap</title>
</head>
<body onload="myFunc()">
<h1 id="test1">Hello World</h1>
<input type="button" value="Say hello" onClick="moveMyself()" />
<div id="myDiv"></div>
<script type="text/javascript">
function myFunc()
{
document.getElementById('test1').innerHTML = 'Good Morning';
}
</script>
</body>
</html>
Try this:
final WebView webview = (WebView)findViewById(R.id.browser);
/* JavaScript must be enabled if you want it to work, obviously */
webview.getSettings().setJavaScriptEnabled(true);
/* WebViewClient must be set BEFORE calling loadUrl! */
webview.setWebViewClient(new WebViewClient() {
#Override
public void onPageFinished(WebView view, String url)
{
webview.loadUrl("javascript:(function() { " +
"document.getElementsByTagName('body')[0].style.color = 'red'; " +
"})()");
}
});
webview.loadUrl("http://code.google.com/android");
It was actually the same thing that Tamilarasi has given me. If somebody wants to call an existing JavaScript function from the html, do the following:
myWebView.setWebViewClient(new WebViewClient() {
public void onPageFinished(WebView view, String url){
myWebView.loadUrl("javascript:myFunc()");
}
});
myWebView.loadUrl("file:///android_asset/myHtml.html");
Try this links i hope this will be help to u:
http://android-er.blogspot.in/2011/10/call-javascript-inside-webview-from.html
Android 4.2.1, WebView and javascript interface breaks
Javascript interface not working with android 4.2