I have written Javascript code that contain callback handler to my android app and inject it from my android code. It fires call back event when we perform play/pause action of video in webview and return event in callback. We are injecting Javascript code form both plateform (iOS and Android)
But unfortunately in iOS, all event value data is getting but in Android it is showing "undefined"
Below is my JavaScript code that is injecting from Android
webView.addJavascriptInterface(new Object() {
#JavascriptInterface
public void getEvent(String data) {
Toast.makeText(getContext(), data , Toast.LENGTH_SHORT).show();
Log.w("TAGGG", "callBackEvent: " + data.toString() );
}
}, "abc");
#Override
public void onPageFinished(WebView view, String url) {
tvErrorMessage.setVisibility(View.INVISIBLE);
String scriptThree = "javascript:window.myApp_event =(function() {" +
"function notifyApp(event) {" +
"var myCallback = console.log(event);"+
"abc.getEvent(event);" + // This is callback for Android
"}" +
"var oExistingEvents = window.myApp_event || [];" +
"oExistingEvents.forEach(notifyApp);" +
"return {" +
"push: function(event) {" +
"notifyApp(event);" +
"}" +
"}" +
"})();";
webView.loadUrl(scriptThree);
}
How can we get that event name that is get in iOS but not in Android?
Related
I hava webView application in Android. I have defined the javascript interface myapp and I can successfully call it from webpage. I am testing the interface in an ajax function but when I call the functions in ajax success callback, nothing happens:
My Javascript codes in webpage:
function notif(t,v){
try {
myapp.Logit("start"); // I can see this message in Logcat
}catch(err){}
$.ajax({
method:"post",
url:"test.asp",
data:{t:t,v:v},
success:function(data){
alert("done"); // Alert works in webpage
try {
myapp.Logit("finish"); // Nothing happens in Logcat
}catch(err){}
}
})
}
And this is the simple function in Android app to log events in logcat:
#JavascriptInterface
public void Logit(String message){
Log.i("message:",message);
}
How are you injecting the Java object into this WebView?
Please make sure that the you are injecting the Java object into the WebView as below. Without that you won't be able to access the Java objects's method in WebView
webView.addJavascriptInterface(new MyApp(), "MyApp");
It will also help to see if you are getting any error in the debug console. Article on how to setup the remote debugging
below is the sample working code. Hope this helps.
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final WebView myWebView = (WebView) findViewById(R.id.webview);
WebSettings webSettings = myWebView.getSettings();
webSettings.setJavaScriptEnabled(true);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
if (0 != (getApplicationInfo().flags & ApplicationInfo.FLAG_DEBUGGABLE))
{ WebView.setWebContentsDebuggingEnabled(true); }
}
myWebView.setWebViewClient(new WebViewClient() {
public void onPageFinished(WebView view, String url) {
System.out.println("Web View loaded");
}
});
Button loadBtn = (Button) findViewById(R.id.load_button);
loadBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String unencodedHtml =
"<!DOCTYPE html>\n" +
"<html>\n" +
" <head>\n" +
" <script src=\"https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js\"></script>\n" +
" <script>\n" +
" $(document).ready(function(){\n" +
" $(\"button\").click(function(){\n" +
" $.ajax({\n" +
" method:\"get\",\n" +
" url: \"https://my-json-server.typicode.com/typicode/demo/posts\", \n" +
" success: function(result){\n" +
" alert(\"done\"); \n" +
" try {\n" +
" MyApp.Logit(\"finish\"); // Nothing happens in Logcat\n" +
" }catch(err){}\n" +
" }});\n" +
" });\n" +
" });\n" +
" </script>\n" +
" </head>\n" +
" <body>\n" +
" <button>Get External Content</button>\n" +
" </body>\n" +
"</html>";
String encodedHtml = Base64.encodeToString(unencodedHtml.getBytes(),
Base64.NO_PADDING);
myWebView.loadData(encodedHtml, "text/html", "base64");
}
});
myWebView.addJavascriptInterface(new MyApp(), "MyApp");
}
}
class MyApp
{
#JavascriptInterface
public void Logit(String message){
Log.i("message:",message);
}
}
Background:-
I am trying to call a #JavascriptInterface annotated method processVideo() form the loadUrl() of webview to get callback when someone click on any video on the webpage.
The following is my approach and it's working perfectly
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_download);
webView = findViewById(R.id.web_view_facebook);
webView.getSettings().setJavaScriptEnabled(true);
webView.getSettings().setPluginState(WebSettings.PluginState.ON);
webView.getSettings().setBuiltInZoomControls(true);
webView.getSettings().setDisplayZoomControls(true);
webView.getSettings().setUseWideViewPort(true);
webView.getSettings().setLoadWithOverviewMode(true);
webView.addJavascriptInterface(this, "Downloader");
webView.setWebViewClient(new WebViewClient() {
#Override
public void onLoadResource(WebView view, String url) {
webView.loadUrl("javascript:(function prepareVideo() { "
+ "var el = document.querySelectorAll('div[data-sigil]');"
+ "for(var i=0;i<el.length; i++)"
+ "{"
+ "var sigil = el[i].dataset.sigil;"
+ "if(sigil.indexOf('inlineVideo') > -1){"
+ "delete el[i].dataset.sigil;"
+ "console.log(i);"
+ "var jsonData = JSON.parse(el[i].dataset.store);"
+ "el[i].addEventListener('click',function(){Downloader.processVideo(jsonData['src'],jsonData['videoID']);});"
+ "}" + "}" + "})()");
}
});
webView.loadUrl("https://m.facebook.com");
}
#JavascriptInterface
public void processVideo(final String vidData, final String vidID) {
try {
Toast.makeText(this, "Download Started", Toast.LENGTH_LONG).show();
} catch (Exception e) {
Toast.makeText(this, "Download Failed: " + e.toString(), Toast.LENGTH_LONG).show();
}
}}
Now The Problem:-
But as i load custom javascript function in loadUrl(), i lost the ability to play video on click.
i think it will happen as i intercepted and load my custom code
So what i want to achieve is when any user click on video, then the video should play and also i get the callback that i wanted at first place
What i have tried so far:-
to play the video on click, i used
addEventListener('click',function(){
var video = document.getElementById(jsonData['videoID']);
video.play(); }
This one is working perfectly to play the video.
but when i use this solution with my callback like following
addEventListener('click',function(){
Downloader.processVideo(jsonData['src'],jsonData['videoID']);
var video = document.getElementById(jsonData['videoID']);
video.play(); }
then I am not able to get callback in my processVideo().
If i use them individually, both functionality (callback and play video) working perfectly inside addEventListener(), but not working together.
This code line: var video = document.getElementById('jsonData['videoID']') throws an error because you used more than two 's in one argument.
Try replacing by var video = document.getElementById(jsonData['videoID']).
Hope this helps.
I have solved this issue and i am pasting complete code here:
webView.setWebViewClient(new WebViewClient()
{
#Override
public void onPageFinished(WebView view, String url)
{
//query_string = "" + url;
// view.loadUrl("javascript:(function() { document.getElementsByTagName('video')[0].play(); })()");
}
#Override
public void onLoadResource(WebView view, String url)
{
// query_string=""+url;
webView.loadUrl("javascript:(function prepareVideo() " +
"{ "
+ "var el = document.querySelectorAll('div[data-sigil]');"
+"var ID;"
+"var SRC;"
+ "for(var i=0;i<el.length; i++)"
+ "{"
+ "var sigil = el[i].dataset.sigil;"
+ "if(sigil.indexOf('inlineVideo') > -1)" +
"{"
+ "delete el[i].dataset.sigil;"
+ "console.log(i);"
+ "var jsonData = JSON.parse(el[i].dataset.store);"
+"ID=jsonData['videoID'];"
+"SRC=jsonData['src'];"
// +"document.getElementsByTagName(\"'+jsonData['videoID']+'\")[0].play();"
+ "el[i].setAttribute('onClick','FBDownloader.processVideo(\"'+jsonData['src']+'\",\"'+jsonData['videoID']+'\");');"
+ "}"
+ "}"
+ "})()");
}
});
JAVA ACTIVITY FUNCTION WHICH IS CALL FROM JAVASCRIPT WEBVIEW
public void processVideo(final String vidData, final String vidID)
{
this.vidData=vidData;
this.vidID=vidID;
Get_Download_Permission();
showtoast("video ID ="+this.vidID);
webView.loadUrl("https://www.facebook.com/video/embed?video_id="+this.vidID);//193766537709747/");
}
I have issue that have strange steps. I have ajax behave rendered on Head render stage
final AbstractDefaultAjaxBehavior behave = new AbstractDefaultAjaxBehavior() {
protected void respond(final AjaxRequestTarget target) {
boolean undoEn = getRequest().getQueryParameters().getParameterValue("undoEn").toBoolean();
if (undoEn) {
mSaveButton.setEnabled(true);
target.add(mSaveButton);
}
}
};
public String getCallbackName() {
return "saveButtonVisibilityToggle";
}
#Override
public void renderHead(IHeaderResponse response) {
String script = getCallbackName() + " = function (e) { Wicket.Ajax.ajax({\"u\": \"" + behave.getCallbackUrl() + " + &undoEn=\"+e+\"\" });}";
response.render(OnDomReadyHeaderItem.forScript(script));
}
Everything works well this behave called every time node changed in tinyMCE editor
settings.addCustomSetting(" setup: function(editor) {" +
" editor.on('NodeChange', function(e) {" +
" editor.save();" +
getCallbackName() + "(editor.undoManager.hasUndo())" +
" });" +
" }");
But sometimes when i leave browser tab, change few tabs (chrome) then use other app for few minutes, and turn back to our tab, ajax url have accidently appeared in browser url.
http://localhost:8080/wicket/bookmarkable/com.tac.kulik.pages.SomePage?3-1.IBehaviorListener.0-contentPanel&entityId=2+++&undoEn=true
this is also quite strange that instead normap parameter pass it's ++++ signs added
by the way this sighns recognized as "2 " so for some reason '+' changed to whitespace
UPDATE 1
Using #svenmeier answer i've page start's infinite loop refreshing. with logs
org.apache.wicket.core.request.mapper.StalePageException: A request to
page '[Page class = x.x.x.CardPage, id = 25, render count = 1]' has been
made with stale 'renderCount'. The page will be re-rendered.
and really for some reason behave link has renderCount 1, but form has 0.
the request from browser
jquery-1.12.4-ver-1476216952000.js:10254 XHR finished loading: GET "http://localhost:8080/wicket/bookmarkable/com.tac.pages.ca…?4-0.IBehaviorListener.0-contentPanel&cardId=1&_=1476873175645&undoEn=true"
I ve add some set of JS to prevent cicling refreshing, But i'we still has Stale exception
"if (editor.undoManager.hasUndo()) { " +
" console.debug('Behave called ');" +
behave.getCallbackScript() +
" }" +
this is my behave
final AbstractDefaultAjaxBehavior behave = new AbstractDefaultAjaxBehavior() {
protected void respond(final AjaxRequestTarget target) {
log.info("Behave called");
boolean undoEn = getRequest().getQueryParameters().getParameterValue("undoEn").toBoolean();
if (undoEn) {
mSaveButton.setEnabled(true);
target.add(mSaveButton);
}
}
//
#Override
protected void updateAjaxAttributes(AjaxRequestAttributes attributes) {
super.updateAjaxAttributes(attributes);
String undoEn = "return {'undoEn': editor.undoManager.hasUndo()};";
attributes.getDynamicExtraParameters().add(undoEn);
}
};
And there is no difference, it could be behave without any realization, page behaviour the same((
final AbstractDefaultAjaxBehavior behave = new AbstractDefaultAjaxBehavior() {
#Override
protected void respond(AjaxRequestTarget target) {
}
};
You should rework your behavior to use dynamic extra parameters instead.
#Override
protected void updateAjaxAttributes(AjaxRequestAttributes attributes)
{
super.updateAjaxAttributes(attributes);
String undoEn = "return {'undoEn': editor.undoManager.hasUndo()}";
attributes.getDynamicExtraParameters().add(undoEn);
}
And:
settings.addCustomSetting(
"setup: function(editor) {" +
" editor.on('NodeChange', function(e) {" +
" editor.save();" +
" " + getCallbackScript() + ";" +
" });" +
"}");
I'm having a problem with my code when running on a Android 4.4.2 KitKat (API 19) emulator...
When I emulate my project on a Android 4.3 (API 18) emulator, it works normally and creates the mathematical expressions with MathJax:
Image of emulator
But when I use a Android 4.4.2 emulator, the app don't work correctly:
Image of emulator
Here is the code of my project:
package com.testes.testesapp;
import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.webkit.WebView;
import android.widget.Button;
import android.widget.EditText;
public class MainActivity extends Activity implements View.OnClickListener {
private int exampleIndex = 0;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
WebView webView = (WebView) findViewById(R.id.webview);
webView.getSettings().setJavaScriptEnabled(true);
//webView.getSettings().setBuiltInZoomControls(true);
webView.loadDataWithBaseURL("http://test", "<script type='text/x-mathjax-config'>"
+ "MathJax.Hub.Config({ "
+ "showMathMenu: false, "
+ "jax: ['input/TeX','output/HTML-CSS'], " // output/SVG
+ "extensions: ['tex2jax.js','toMathML.js'], "
+ "TeX: { extensions: ['AMSmath.js','AMSsymbols.js',"
+ "'noErrors.js','noUndefined.js'] }, "
// + "'SVG' : { blacker: 30, "
// + "styles: { path: { 'shape-rendering': 'crispEdges' } } } "
+ "});</script>"
+ "<script type='text/javascript' "
+ "src='file:///android_asset/MathJax/MathJax.js'"
+ "></script>"
+ "<span id='math'></span>","text/html","utf-8","");
EditText edit = (EditText) findViewById(R.id.edit);
edit.setBackgroundColor(Color.LTGRAY);
edit.setTextColor(Color.BLACK);
edit.setText("");
Button btnShow = (Button) findViewById(R.id.btnShow);
btnShow.setOnClickListener(this);
Button btnClear = (Button) findViewById(R.id.btnClear);
btnClear.setOnClickListener(this);
Button btnExample = (Button) findViewById(R.id.btnExample);
btnExample.setOnClickListener(this);
}
private String doubleEscapeTeX(String s) {
String t="";
for (int i=0; i < s.length(); i++) {
if (s.charAt(i) == '\'') t += '\\';
if (s.charAt(i) != '\n') t += s.charAt(i);
if (s.charAt(i) == '\\') t += "\\";
}
return t;
}
private String getExample(int index) {
return getResources().getStringArray(R.array.tex_examples)[index];
}
public void onClick(View v) {
if (v == findViewById(R.id.btnShow)) {
WebView webView = (WebView) findViewById(R.id.webview);
EditText edit = (EditText) findViewById(R.id.edit);
webView.loadUrl("javascript:document.getElementById('math').innerHTML='\\\\["
+ doubleEscapeTeX(edit.getText().toString()) + "\\\\]';");
webView.loadUrl("javascript:MathJax.Hub.Queue(['Typeset',MathJax.Hub]);");
}
else if (v == findViewById(R.id.btnClear)) {
WebView webView = (WebView) findViewById(R.id.webview);
EditText edit = (EditText) findViewById(R.id.edit);
edit.setText("");
webView.loadUrl("javascript:document.getElementById('math').innerHTML='';");
}
else if (v == findViewById(R.id.btnExample)) {
WebView webView = (WebView) findViewById(R.id.webview);
EditText edit = (EditText) findViewById(R.id.edit);
edit.setText(getExample(exampleIndex++));
if (exampleIndex > getResources().getStringArray(R.array.tex_examples).length - 1)
exampleIndex=0;
webView.loadUrl("javascript:document.getElementById('math').innerHTML='\\\\["
+ doubleEscapeTeX(edit.getText().toString()) + "\\\\]';");
webView.loadUrl("javascript:MathJax.Hub.Queue(['Typeset',MathJax.Hub]);");
}
}
}
When I press the "Example" or the "Show" button, LogCat emits the errors:
I/chromium(1254): [INFO:CONSOLE(1)] "Uncaught TypeError: Cannot set property 'innerHTML' of null", source: http://test/ (1)
I/chromium(1254): [INFO:CONSOLE(1)] "Uncaught ReferenceError: MathJax is not defined", source: http://test/ (1)
I have no idea how to fix this problem, and would like somebody's help to solve this. Thanks.
I got this problem too.
Here is my solution:
change your base URL from "http://test" to "http://test/"
change this code webView.loadUrl(..) to webView.evaluateJavascript(..);. Especially for code where we want to load innerHTML. Don't forget to add anotation #TargetApi(Build.VERSION_CODES.KITKAT) because it's only for Android 4.4 and above
never put webView.loadWithBaseUrl(..) in the same process with webView.loadUrl(..). Because If webView.loadUrl(..) was loaded before webView.loadWithBaseUrl(..) finished, it will raise error as OP stated above.
For number 3, your codes is already conform with this (because in your codes, webView.loadUrl(..) execution was already separated with webView.loadWithBaseUrl(..) by using OnClick event. So, don't pay attention to it.
But if your apps need to load them at one event, consider to separate them by using this code:
`
private void initiateWebView(){
webViewEquationDisplay.setWebViewClient(new WebViewClient() {
#Override
public void onPageFinished(WebView view, String url) {
super.onPageFinished(view, url);
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT){
loadUrlKitKat(equationSymbolFinal+equationToBeDisplayedFinal);
}
else{
webViewEquationDisplay.loadUrl("javascript:document.getElementById('math').innerHTML='<font color=\"yellow\">`"+equationToBeDisplayedFinal+"`</font>';");
}
webViewEquationDisplay.loadUrl("javascript:MathJax.Hub.Queue(['Typeset',MathJax.Hub]);");
}
});
final String mathJaxOfflineUrl = "file:///android_asset/MathJax/MathJax.js";
webViewEquationDisplay.loadDataWithBaseURL("http://bar/", "<script type='text/x-mathjax-config'>"
+"MathJax.Hub.Config({ "
+"showMathMenu: false, "
+"jax: ['input/AsciiMath','output/HTML-CSS'], "
+"extensions: ['asciimath2jax.js'], "
+"AsciiMath: { fixphi: true, useMathMLspacing: true, displaystyle: false, decimalsign: \".\" }, "
+"});</script>"
+"<script type='text/javascript' "
+"src='"+mathJaxOfflineUrl+"'"
+"></script><span id='math'></span>","text/html","utf-8","");
}
#TargetApi(Build.VERSION_CODES.KITKAT)
private void loadUrlKitKat(String param){
webViewEquationDisplay.evaluateJavascript("javascript:document.getElementById('math').innerHTML='<font color=\"#97FD97\">`"+param+"`</font>';",null);
}
`
good luck
I had the same problem when I moved different javascript functions out of the main page to an separate .js file. For some reason, Android can't find externally-loaded JavaScript webview functions from Java - only the ones in the main page. Once I moved the function back from the JS file, it immediately started working.
Try making a "proxy" function like this directly inside the main HTML:
function proxy() {
call_some_other_function_from_JS_file();
}
This worked for me. I'm sure there must be a way to get find these functions, because I didn't have this problem on iOS. Someone please comment if you know a better way.
webview.evaluateJavascript("javascript:document.getElementById('math').innerHTML='"+doubleEscapeTeX(questn)+"';",null);
webview.loadUrl("javascript:MathJax.Hub.Queue(['Typeset',MathJax.Hub]);");
This is the sollution for api 19 or above
I am calling a simple JS function to set values of some html contents, but its not working
Here is the JS function
function SetEdits(name,email,pic,date)
{
document.getElementById("myPic").src=pic;
document.getElementById("fullname").value=name;
document.getElementById("email").value=email;
}
and here is the code from android activity
edit.loadUrl("edit.html");
edit.loadUrl("javascript:SetEdits('"+name+"','"+email+"','"+picture+"','"+date+"')");
its not settings these fileds.. is there any problem with the synax where i am calling this function in native activity?
You're probably ending up evaluating the JavaScript before the "edit.html" page has loaded. Try this:
// I'm assuming the real path is something like file:///android_asset/edit.html
edit.loadUrl("edit.html");
edit.setWebViewClient(new WebViewClient() {
#Override
public void onPageFinished(WebView view, String url) {
if (Uri.parse(url).getPath() == "edit.html") {
view.loadUrl("javascript:SetEdits('" + name+"','" + email + "','" +
picture + "','" + date + "')");
}
}
Have you enabled the javascript for the webview ?
You have to setup a javascript interface between your app and html.
Here is some details Webapp guid