How to get the full height of in android WebView?

Question

I have a RelativeLayout with WebView. I am loading some generated html text into that WebView. After loading the data WebView height exceeding the screen. Now I need the height of the entire WebView. Till now I tried WebView#getHeight(), WebView#getBottom() but I'm getting the height of visible content.

How to get the total height of WebView.?

Johnnyjumpup

you have to use javascript for that. – Beak

Can you tell me how ? – Johnnyjumpup

Answer 1

Finally I got the answer for my question. Here is the answer.

After loading WebView we will get call in WebViewClient#onPageFinished there we need to call javascript to get the height of full content of WebView

WebViewClient class

/**
 * Custom web client to perform operations on WebView
 */
class WebClient extends WebViewClient {

    @Override
    public void onPageFinished(WebView view, String url) {
            view.loadUrl("javascript:AndroidFunction.resize(document.body.scrollHeight)");
        }
    }
}

After that we will get callback with height in WebInterface class which is Registered as JavascriptInterface

/**
 * WebView interface to communicate with Javascript
 */
public class WebAppInterface {

    @JavascriptInterface
    public void resize(final float height) {
        float webViewHeight = (height * getResources().getDisplayMetrics().density);
        //webViewHeight is the actual height of the WebView in pixels as per device screen density
    }
}

Johnnyjumpup

resizing is crucial if actual height in screen pixels is needed. thanks a lot. – Guenon

hey, what is readWebView? Ah- an instance of WebAppInterface? – Stationery

No it's webView instance. Edited answer. Thanks man. I forgot that it's my answer. ;) – Johnnyjumpup

how to use this class WebAppInterface – Minelayer

go through this link developer.android.com/guide/webapps/webview#BindingJavaScript – Johnnyjumpup

Since WebViewClient.onPageFinished() only gets called when the page had finished loading, this solution falls short when the size of the content changes post loading (e.g. Javascript content rendered after page finished loading, user interactions with expandable and collapsible sections) – Dole

In this case we can have one more javascript call from web page when content is expanded/collapsed. – Johnnyjumpup

@Dole I'm also facing similar problem. Do have any clue? – Mc

Answer 2

Wrap your WebView within a ScrollView and webView.getHeight() will return the height of the actual WebView content. Make sure your WebView's height attribute is set to wrap_content.

<ScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <WebView
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
    </WebView>
</ScrollView>

Periotic

I tried this case also, but if we load 10 high quality images it is giving out off memory error. And one more thing keeping WebView in ScrollView is not recommended. – Johnnyjumpup

@Johnnyjumpup You're probably getting OOM because the images are much higher res than what the device can handle, consider if a high res image is 50mb, you load 10 = 250mb, and then on top of that you have the app, the os, etc. running on oftentimes devices with less than a gig of ram, you're going to kill your app quickly. – Polythene

I think you tried to explain part of my above comment. (OOM out off memory error) :P Thanks. – Johnnyjumpup

If you are using scroll view among with nested scroll view try to set android:nestedScrollingEnabled="true" inside scroll view – Shalom

NEVER wrap webViews inside scrollviews. It will make the WebView expand to max size and the webView will believe all of it's content is shown. WebView should handle content visibility, not ScrollView. – Decasyllabic

Answer 3

kotlin: myWebView.contentHeight

Autosome

In my case I aloso need multiply myWebView.contentHeigth to Resources.getSystem().displayMetrics.density to get real height. – Philistine

Last comment was what I needed. I will post this as new answer just in case anyone misses it. – Craig

Answer 4

public class CustomWebView extends WebView{
    public CustomWebView(Context context) {
        super(context);
    }
    int ContentHeight = 0;
    public int getContentHeight(){
        if(ContentHeight==0)
            ContentHeight = computeVerticalScrollRange();
        return ContentHeight;
    }
}

Webview has protected method computeVerticalScrollRange(). you can access this method by creating custom one.

((CustomWebView) webView).getContentHeight())

Headwater

the word compute tends to indicate that some work is being done, possibly heavy. – Beak

I get a ClassCastException with this solution. Any work arounds? – Periotic

Nevermind, I figured it out. See my full answer below. – Periotic

Answer 5

In your Java class add the getWindow()

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        getWindow().requestFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.activity_webview);
}

Sansculotte

Answer 6

My Answer:-

I think you have to remove padding properties from your layout.xml file

(i.e) Remove the following content from your XML file and try it.

android:paddingBottom    
android:paddingLeft    
android:paddingRight    
android:paddingTop

Hope it helps!!

Supplementary

Answer 7

private int getScale(){
    Display display = ((WindowManager) 
    getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay(); 
    int width = display.getWidth(); 
    Double val = new Double(width)/new Double(PIC_WIDTH);
    val = val * 100d;
    return val.intValue();
}

check this link! for more information

Hystero

Answer 8

Actual height in Kotlin: myWebView.contentHeight * Resources.getSystem().displayMetrics.density

Craig