Android : Simple web application crashes on links other then the http scheme - android

I am a beginner in developing for the Android, so excuse me if this is obvious. I created a simple web application using the samples from android.com however, when a link like tel: or mailto: is clicked, the application crashes and askes me to force quit. I was wondering if anyone could tell me why.
public class MyApplication extends Activity {
WebView mWebView;
private class InternalWebViewClient extends WebViewClient {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
// This is my web site, so do not override; let my WebView load the page
if (Uri.parse(url).getHost().equals("m.mydomain.nl")) {
return false;
} else {
// Otherwise, the link is not for a page on my site, so launch another Activity that handles URLs
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
startActivity(intent);
return true;
}
}
}
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if ((keyCode == KeyEvent.KEYCODE_BACK) && mWebView.canGoBack()) {
mWebView.goBack();
return true;
}
return super.onKeyDown(keyCode, event);
}
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
/* Use the WebView class to display website */
mWebView = (WebView) findViewById(R.id.webview);
mWebView.setWebViewClient(new InternalWebViewClient());
mWebView.getSettings().setJavaScriptEnabled(true);
mWebView.loadUrl("http://m.mydomain.nl/");
}
}

Sorry to be so stupid, this actualy fixed it. With mailto, there is no host, thus getHost() will return null and causes the exception.
private class InternalWebViewClient extends WebViewClient {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
// This is my web site, so do not override; let my WebView load the page
if (Uri.parse(url).getHost() != null && Uri.parse(url).getHost().equals("m.domain.nl")) {
return false;
} else {
// Otherwise, the link is not for a page on my site, so launch another Activity that handles URLs
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
startActivity(intent);
return true;
}
}
}

Related

Don't navigate to other pages in WebView,disable links and references and go back to first page

I have a webView in Android and I open a html webpage in it. But it's full of links and images: when I click one of them it loads in my webview.I want to disable this behaviour, so if I click on a link, don't load it and go back to the first page.
I've tried this solution and edited a bit for myself, but it does not work:
webSettings.setJavaScriptEnabled(myWebViewClient.equals(true));
This opens a white page but I want to open the main URL. My webviewclient code:
public class MainActivity extends Activity {
public static String URL = "http://www.example.com/";
private WebView webView = null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
this.webView = (WebView) findViewById(R.id.webview);
MyWebViewClient myWebViewClient = new MyWebViewClient();
WebSettings webSettings = webView.getSettings();
webSettings.setJavaScriptEnabled(myWebViewClient.equals(true));
webView.reload();
webView.loadUrl(URL);
webSettings.setDisplayZoomControls(true);
webView.setWebViewClient(new WebViewClient());
}
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if(event.getAction() == KeyEvent.ACTION_DOWN) {
switch(keyCode) {
case KeyEvent.KEYCODE_BACK:
if(webView.canGoBack()){
webView.goBack();
return true;
}
break;
}
}
return super.onKeyDown(keyCode, event);
}
public void onBackPressed(){
if (webView.canGoBack()){
webView.goBack();
}
else{
super.onBackPressed();
}
}
}
you need to overwrite onPageStarted in WebViewClient:
#Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
//here check url i.e equals to your that html page
// if url equals not load url
and for go to back page check:
if(view.canGoBack())
// load first page url
}
You need a WebViewClient that overrides loading url:
webView.setWebViewClient(new WebViewClient() {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
// url is the url to be loaded
return true; // override url (don't load it)
return false; // let url load
}
});
You can always return true to stay on the same page.
To open Main Url and stay on it, use this:
webview.loadUrl(MainUrl);
and then override loading url and always return true:
webView.setWebViewClient(new WebViewClient() {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
return true;
}
});

Parameter passed from WebView to Activity

I have to call web page from WebView to Activity.This is a two way communication which I want to achieve between an Activity and a page loaded in WebView.
Edit
private class MyWebViewClient extends WebViewClient {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
if (Uri.parse(url).getHost().equals("www.example.com")) {
return false;
}
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
startActivity(intent); return true;
}
}
Extend the WebViewCLient (example from tutorial):
private class MyWebViewClient extends WebViewClient {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
if (Uri.parse(url).getHost().equals("www.example.com")) {
// This is my web site, so do not override; let my WebView load the page
return false;
}
// Otherwise, the link is not for a page on my site, so launch another Activity that handles URLs
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
startActivity(intent);
return true;
}
}
Have a look: http://developer.android.com/guide/webapps/webview.html
Just create an activity with a webview inside and load the URL.

WebView not showing website correctly

WebView is not showing website correctly. Any help would be great!
The code ive used work on all another site. Not sure whats the issue. Any thing I should add? Works well in chrome and other browsers so don't know what to do. Any help would be great!
WebView
Chrome
public class Website extends Activity {
WebView myWebView;
LinearLayout root;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.website);
myWebView = (WebView) findViewById(R.id.webView);
myWebView.loadUrl("http://dspart.org");
root = (LinearLayout) findViewById(R.id.root);
WebSettings webSettings = myWebView.getSettings();
webSettings.setJavaScriptEnabled(true);
myWebView.addJavascriptInterface(new WebAppInterface(this), "Android");
myWebView.setWebViewClient(new WebViewClient());
myWebView.getSettings().setBuiltInZoomControls(true);
myWebView.getSettings().setSupportZoom(true);
myWebView.getSettings().setUseWideViewPort(true);
myWebView.getSettings().setLoadWithOverviewMode(true);
getActionBar().setDisplayHomeAsUpEnabled(true);
}
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 showToast(String toast) {
Toast.makeText(mContext, toast, Toast.LENGTH_SHORT).show();
}
private class MyWebViewClient extends WebViewClient {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
if (Uri.parse(url).getHost().equals("http://dspart.org")) {
// This is my web site, so do not override; let my WebView load the page
return false;
}
// Otherwise, the link is not for a page on my site, so launch another Activity that handles URLs
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
startActivity(intent);
return true;
}
}
}
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if(event.getAction() == KeyEvent.ACTION_DOWN){
switch(keyCode) {
case KeyEvent.KEYCODE_BACK:
if(myWebView.canGoBack()) {
myWebView.goBack();
}
else {
root.removeView(myWebView);
myWebView.removeAllViews();
myWebView.destroy();
this.finish();
}
return true;
}
}
return super.onKeyDown(keyCode, event);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
NavUtils.navigateUpFromSameTask(this);
root.removeView(myWebView);
myWebView.removeAllViews();
myWebView.destroy();
this.finish();
return true;
default:
return super.onOptionsItemSelected(item);
}
}}
YourWebView.getSettings().setJavaScriptEnabled(true);
try enabling javascript on your webview! code snippet above :
Seems like there is an error in the following line
if (Uri.parse(url).getHost().equals("http://dspart.org"))
getHost will return dspart.org and not the url with http. Try after modifying it. Thanks
Refer - http://developer.android.com/reference/android/net/Uri.html#getHost()

How to control the Android WebView history/back stack?

I am trying to figure out a way to handle the WebView back stack similar to how the Android web browser handles it when the back button is pressed from within my own app's WebView.
The problem has to do with Javascript redirects. The WebView back stack appears to contain URLs that simply redirect. Here is my relevant code:
private class ArticleWebViewClient extends WebViewClient {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(url);
return true;
}
}
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK)
{
WebView wv = (WebView)findViewById(R.id.web);
if (wv.canGoBack())
{
wv.goBack();
return true;
}
}
return super.onKeyDown(keyCode, event);
}
As you can see, pressing the back button selects the previous URL in the stack, which loads in the WebView itself after shouldOverrideUrlLoading() is called. I'm actually doing a lot more inside shouldOverrideUrlLoading() that isn't relevant for this particular question, so "remove my WebViewClient implementation" won't work for me. At any rate, when the previous URL is a Javascript redirect, that URL loads and then Javascript immediately redirects to the URL the WebView was just at. I can't disable Javascript because the website depends on it. I also can't change the website (third-party).
The result of this redirection issue is a vicious cycle for the end-user who is frantically pressing back just to be slightly faster than the Android webpage processing engine.
Now here is where it gets interesting: The Android web browser handles the back button just fine for Javascript redirects! It follows the redirects just fine but the back button does what a user expects it to do. That means it is possible to correctly handle this scenario. How does the Android web browser handle this problem?
Detect when url loading is triggered by the user, and add those to the backstack instead.
private List<String> previous = new ArrayList<String>();
private String mLastUrl;
webview.setWebViewClient(new WebViewClient() {
#Override
public void onPageFinished(WebView view, String url) {
Log.i("DebugDebug", "OnPageFinished " + url);
mLastUrl = url;
super.onPageFinished(view, url);
}
});
webview.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View view, MotionEvent motionEvent) {
WebView.HitTestResult hr = ((WebView)view).getHitTestResult();
if (hr != null && mLastUrl != null) {
if (previous.isEmpty() || !previous.get(previous.size() - 1).equals(mLastUrl)) {
previous.add(mLastUrl);
}
Log.i("DebugDebug", "getExtra = " + hr.getExtra() + "\t\t Type = " + hr.getType());
}
return false;
}
});
#Override
public void onBackPressed() {
Log.i("DebugDebug", "onBackPressed");
int size = previous.size();
if (size > 0){
webview.loadUrl(previous.get(size - 1));
previous.remove(size - 1);
} else {
super.onBackPressed();
}
}
your onKeyDown should look like these
#Override
public boolean onKeyDown(int keyCode, KeyEvent event)
{
if ((keyCode == KeyEvent.KEYCODE_BACK) && myWebView.canGoBack()) {
myWebView.goBack();
return true;
}
return super.onKeyDown(keyCode, event);
}
here myWebView is declared in the Activity's onCreate
I had a similar problem with yours and found how to figure it out. Here is my answer.
When I click the first link(www.new.a) it automatically redirects other link(mobile.new.a). Usually the links redirect two or three, and my solution have been worked on almost every redirect links. I hope this answer help you out with annyoing redirecting links.
I finally figured out that. You need a WebViewClient with four APIs. There are shouldOverrideUrlLoading(), onPageStarted(), onPageFinished(), and doUpdateVisitedHistory() in the WebViewClient. All the APIs you need is API 1 so don't worry about.
Here is my answer. Check out that! :)
The correct answer is to return false on shouldOverrideUrlLoading() as described in https://stackoverflow.com/a/8644978/5022858 and https://developer.android.com/reference/android/webkit/WebViewClient.html. This prevents redirects from being added to the history list.
private class ArticleWebViewClient extends WebViewClient {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
return false;
}
}
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK)
{
WebView wv = (WebView)findViewById(R.id.web);
if (wv.canGoBack())
{
wv.goBack();
return true;
}
}
return super.onKeyDown(keyCode, event);
}
This shouldOverrideUrlLoading method should return false if you want to handle the link in your webview rather than system browser, and do not call view.loadUrl(url), your webview will load url automatically if you return false. The history will be not correct if you load url manually.
boolean isGoBack = false; //back key is pressed
private long goBackTime = 0; //
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if ((keyCode == KeyEvent.KEYCODE_BACK) && mWebView.canGoBack()) {
isGoBack = true;
goBackTime = System.currentTimeMillis();
mWebView.goBack();
return true;
}
return super.onKeyDown(keyCode, event);
}
Webview mWebView.
setWebViewClient(new WebViewClient() { //setWebViewClient
#Override
public boolean shouldOverrideUrlLoading (WebView view, String url){
if (!TextUtils.isEmpty(startUrl) && !startUrl.equals(url) && isGoBack && System.currentTimeMillis() - goBackTime < 600) {
isGoBack = false;
if (mWebView.canGoBack()) {
mWebView.goBack();
} else {
finish(); //activity finish
}
} else {
view.loadUrl(url);
isGoBack = false;
return true;
}
return false;
}
#Override
public void onPageStarted (WebView view, String url, Bitmap favicon){
super.onPageStarted(view, url, favicon);
startUrl = url;
}
}
this snippet work for me, try it:
#Override
public void onBackPressed() {
BlankFragment fragment = (BlankFragment)
getSupportFragmentManager().findFragmentByTag("webView");
if (fragment.canGoBack()) {
fragment.goBack();
} else {
super.onBackPressed();
}
}

Android WebView setting download folder location

I've added a webview activity and would like to control which folder any downloaded that my end users will download via my app. The files will be pdf files and I would like them to go into a specific folder that my app uses rather than the default download folder.
public class myweb extends Activity {
private WebView myWebView;
private String LOG_TAG = "AndroidWebViewActivity";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.knitweb);
myWebView = (WebView) findViewById(R.id.webView1);
//enable Javascript
myWebView.getSettings().setJavaScriptEnabled(true);
//loads the WebView completely zoomed out
myWebView.getSettings().setLoadWithOverviewMode(true);
//true makes the Webview have a normal viewport such as a normal desktop browser
//when false the webview will have a viewport constrained to it's own dimensions
myWebView.getSettings().setUseWideViewPort(true);
//override the web client to open all links in the same webview
myWebView.setWebViewClient(new MyWebViewClient());
myWebView.setWebChromeClient(new MyWebChromeClient());
//Injects the supplied Java object into this WebView. The object is injected into the
//JavaScript context of the main frame, using the supplied name. This allows the
//Java object's public methods to be accessed from JavaScript.
myWebView.addJavascriptInterface(new JavaScriptInterface(this), "Android");
//load the home page URL
//myWebView.loadUrl("http://demo.mysamplecode.com/Servlets_JSP/pages/androidWebView.jsp");
myWebView.loadUrl("http://www.patonsyarns.com/pattern.php?PID=4521&cps=21191");
myWebView.setDownloadListener(new DownloadListener() {
public void onDownloadStart(String url, String userAgent,
String contentDisposition, String mimetype, long contentLength) {
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setData(Uri.parse(url));
startActivity(intent);
}
});
}
private class MyWebViewClient extends WebViewClient {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
if (Uri.parse(url).getHost().equals("demo.mysamplecode.com")) {
return false;
}
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
startActivity(intent);
return true;
}
}
private class MyWebChromeClient extends WebChromeClient {
//display alert message in Web View
#Override
public boolean onJsAlert(WebView view, String url, String message, JsResult result) {
Log.d(LOG_TAG, message);
new AlertDialog.Builder(view.getContext())
.setMessage(message).setCancelable(true).show();
result.confirm();
return true;
}
}
public class JavaScriptInterface {
Context mContext;
// Instantiate the interface and set the context
JavaScriptInterface(Context c) {
mContext = c;
}
//using Javascript to call the finish activity
public void closeMyActivity() {
finish();
}
}
//Web view has record of all pages visited so you can go back and forth
//just override the back button to go back in history if there is page
//available for display
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if ((keyCode == KeyEvent.KEYCODE_BACK) && myWebView.canGoBack()) {
myWebView.goBack();
return true;
}
return super.onKeyDown(keyCode, event);
}
I do not know in advance which files the users will be downloading other than that they will be pdf files.
Any help would be great
Thanks
I’m affraid the only solution is to use DownloadListener to catch the event and download the file manually.
Download a file example: http://www.androidhive.info/2012/04/android-downloading-file-by-showing-progress-bar/
DownloadListener example: How do I use DownloadListener?

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