I have a webview that load up a URL from internet, but when there is no connectivity (onReceiedError) it loads up a locally saved html document in assets folder.
but when I press back button on that particular activity (which loads up the local HTML) it doesn't go back to the previous activity instead tries to refresh the page.. It is only after 4-5 Back presses it goes back.
here is my code.
private class HelloWebViewClient extends WebViewClient{
#Override
public void onReceivedError(WebView view, int errorCode,
String description, String failingUrl) {
mWebView.getSettings().setBuiltInZoomControls(false);
mWebView.getSettings().setLoadWithOverviewMode(false);
mWebView.getSettings().setUseWideViewPort(false);
mWebView.loadUrl("file:///android_asset/offline.html");
}
public boolean shouldOverrideUrlLoading(WebView webview, String url)
{
webview.loadUrl(url);
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);
}
#Override
public void onBackPressed()
{
this.finish();
overridePendingTransition (0, R.anim.right_slide_out);
return;
}
}
Works fine with the normal webpage to load from Internet.
coz in onReceivedError you change the url . so there will be no goback event
you have to just show toast message and delete mWebView.loadUrl("file:///android_asset/offline.html");
Related
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;
}
});
I have a requirement in my app where I need to render the multiple web pages in webview and provide the goback() method.
But unfortunately goback() method does not work in the case when we load the url(one of the url from multiple pages) which does not exit(Web page not available)and then we try to call the goBack()
it seems you complicate your code you just try simple code below
#Override
public void onBackPressed() {
if (webView.canGoBack()) {
webView.goBack();
} else {
super.onBackPressed();
}
}
this is simple code work fine for you,i dont know if you are using flag for other reasons.
You can do like this.
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK && webView.canGoBack()) {
webView.goBack();
return true;
}
return super.onKeyDown(keyCode, event);
}
And you Web page not available,you can use onReceivedError method.
webView.setWebViewClient(new WebViewClient() {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(url);
return true;
}
#TargetApi(Build.VERSION_CODES.M)
#Override
public void onReceivedError(WebView view, WebResourceRequest request, WebResourceError error) {
super.onReceivedError(view, request, error);
if (request.isForMainFrame()) {
// you can do something when you Web page not available
// webView.goBack();
}
}
});
Hi I am developing android application in which I am using one web view. My web view has some data which redirect to some different link. So when I click it should come back to previous content. And finally it should close the web view when it comes to landing page. I tried it in following ways :
webView = new WebView(this);
webView.setWebViewClient(new WebViewClient() {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
if (url.contains(URLManager.URL_DICOM_BACK_PRESSED_URL)) {
processBackPressed();
return true;
} else {
return super.shouldOverrideUrlLoading(view, url);
}
}
#Override
public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
if (failingUrl.contains(URLManager.URL_DICOM_BACK_PRESSED_URL)) {
processBackPressed();
} else {
showError("Server unreachable");
}
}
#Override
public void onPageFinished(WebView view, String url) {
super.onPageFinished(view, url);
}
});
webView.getSettings().setJavaScriptEnabled(true);
webView.loadUrl(url);
#Override
public void onBackPressed() {
if (webView != null && webView.canGoBack()) {
webView.goBack();
} else {
processBackPressed();
}
}
So problem is that whenever it is coming back to previous page it is fist showing current page and then previous page.So looks like first refresh the page and then load previous url. Am I doing anything wrong. Need Some Help. Thank you.
Try this -
#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{
finish();
}
return true;
}
}
return super.onKeyDown(keyCode, event);
}
I have an android application in which I have a button.User presses that button then it start an activity that contain a webview.
The problem is in order to finish webview activity when user press back button in the first time,I tried to finish that activity But not working, It went back to history page.I pressed back button several time,webview activity finish.
How can my app finish webview activity when user press button in the first time?
Here my webview activity
public class SocialWebViewActivity extends Activity {
private WebView webView;
ProgressDialog mProgress;
public static String url="";
#SuppressLint("SetJavaScriptEnabled")
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.social_web_view);
webView = (WebView) findViewById(R.id.social_web_view_external);
webView.getSettings().setJavaScriptEnabled(true);
// the init state of progress dialog
mProgress = ProgressDialog.show(this, "Web", "Loading...");
// add a WebViewClient for WebView, which actually handles loading data from web
webView.setWebViewClient(new WebViewClient() {
// load url
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(url);
return true;
}
// when finish loading page
public void onPageFinished(WebView view, String url) {
if(mProgress.isShowing()) {
mProgress.dismiss();
}
view.clearHistory();
}
#Override
public void onReceivedError(WebView view, int errorCode,
String description, String failingUrl) {
Toast.makeText(getApplicationContext(), description, Toast.LENGTH_LONG).show();
if(mProgress.isShowing()) {
mProgress.dismiss();
}
super.onReceivedError(view, errorCode, description, failingUrl);
}
});
if(!"".equals(SocialWebViewActivity.url)){
webView.loadUrl(SocialWebViewActivity.url);
}
}
}
Override the onKeyDown(param)
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if ((keyCode == KeyEvent.KEYCODE_BACK) ) {
webView.clearHistory(); // clear history
finish(); // finish activity
return true;
}
return super.onKeyDown(keyCode, event);
}
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();
}
}