user2794306
user2794306

Reputation: 175

How to set backGround color Black and text white in android webview

package com.example.webviewtheme;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.webkit.WebView;

public class MainActivity extends Activity {
WebView webview1;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        webview1=(WebView)findViewById(R.id.webView1);

        String rawHTML = "<HTML>"+  
         "<body style='color: #000000; background-color: #ffffff'><h1>Hello Android </h1></body>"+  
     "</HTML>";
        webview1.setBackgroundColor(00000000);
        webview1.loadData(rawHTML, "text/HTML", "UTF-8");
    }

}

This is My code i want to set background color black and text white of webView i have tried to apply In Html But Unable to get Out put please help me how to set Night Mode in Webview text and backGround

Upvotes: 0

Views: 35111

Answers (10)

MHP
MHP

Reputation: 2731

use this

webview1=(WebView)findViewById(R.id.webView1);
    String rawHTML = "<HTML>"+ 
     "<head>"+"<style  type=\"text/css\">"+
     "body,h1{color: #000000;"+
     "background-color: #ffffff;}"+
     "</style></head>"+
     "<body><h1>Hello Android </h1></body>"+  
 "</HTML>";
    webview1.loadData(rawHTML, "text/html; charset=UTF-8",null);

UPDATE 20/June:

if you want to change web page css after it's load finished (for example when load webPageAddress with loadUrl) you can do it like this:

  • set javaScript enable on webView

    webView.getSettings().setJavaScriptEnabled(true);
    
  • set listener on page load finish

    webView.setWebViewClient(new WebViewClient() {
       @Override
       public void onPageFinished(WebView view, String url) {
          // Inject CSS on PageFinished
          injectCSS();
          super.onPageFinished(view, url);
       }
    });
    
  • inject CSS

    private void injectCSS() {
      webView.loadUrl(
        "javascript:document.body.style.setProperty(\"color\", \"white\");"
      );
      webView.loadUrl(
        "javascript:document.body.style.setProperty(\"background-color\", \"black\");"
      );
    }
    

Upvotes: 10

Roman Black
Roman Black

Reputation: 3497

You can invert colors of a WebView using its parent.

  1. You need to implement inversion in parent. I'm using a FrameLayout, but you can use some other form of layout.

    public class WebViewInverter extends FrameLayout {
         public WebViewInverter(Context context) {
            super(context);
            init();
        }
    
        public WebViewInverter(Context context, AttributeSet attrs) {
            super(context, attrs);
            init();
        }
    
        public WebViewInverter(Context context, AttributeSet attrs, int defStyleAttr) {
            super(context, attrs, defStyleAttr);
            init();
        }
    
        public WebViewInverter(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
            super(context, attrs, defStyleAttr, defStyleRes);
            init();
        }
    
        private boolean nightMode = false;
    
        private Paint paint = new Paint(); 
        private ColorFilter cf;
        private Rect inversionRect;
    
        @Override protected void dispatchDraw(Canvas c){
                inversionRect = new Rect(0, 0, getWidth(), getHeight());
                Bitmap b = Bitmap.createBitmap(getWidth(), getHeight(), Config.ARGB_8888);
                Canvas cc = new Canvas(b);
                super.dispatchDraw(cc);
                paint.setColorFilter(null);
                c.drawBitmap(b, 0, 0, paint);
                paint.setColorFilter(cf);
                c.drawBitmap(b, inversionRect, inversionRect, paint);
        }
    
        private void init(){
            float[] mat = new float[]
            {
                -1,  0,  0, 0,  255,
                 0, -1,  0, 0,  255,
                 0,  0, -1, 0,  255,
                 0,  0,  0, 1,  0
            };
            cf = new ColorMatrixColorFilter(new ColorMatrix(mat));
        }
    
    }
    
  2. Place Your WebView inside inverter in your layout's file:

    <your.package.name.WebViewInverter
        android:id="@+id/view_inverter"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:layout_marginLeft="@dimen/reader_side_margins"
        android:layout_marginTop="@dimen/reader_top_margin"
        android:layout_marginRight="@dimen/reader_side_margins"
        android:layout_marginBottom="@dimen/reader_bottom_margin">
    
        <ru.yandex.reader.widget.ReaderView
            android:id="@+id/view_reader"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>
    
    </your.package.name.WebViewInverter>
    

The WebView should be inverted.

Upvotes: 0

Omkar Ghodke
Omkar Ghodke

Reputation: 9

Android have built-in theme for night mode called Theme.AppCompat.DayNight theme

<style name="MyTheme" parent="Theme.AppCompat.DayNight"> <!-- Blah blah --> </style>

To know more, how to implement this functionality check out the link below

https://medium.com/@chrisbanes/appcompat-v23-2-daynight-d10f90c83e94

Upvotes: -1

Snehal Poyrekar
Snehal Poyrekar

Reputation: 735

webview.setBackgroundColor(0) makes webview transparent.

You will need to set bg color black in the HTML tag bg.

Upvotes: 2

Lucid Dev Team
Lucid Dev Team

Reputation: 641

Here is something that will inject Javascript into a webpage to make it invert colors:

String js ="javascript: ("
                    +"function () { "

                    +"var css = 'html {-webkit-filter: invert(100%);' +"
                    +"    '-moz-filter: invert(100%);' + "
                    +"    '-o-filter: invert(100%);' + "
                    +"    '-ms-filter: invert(100%); }',"

                    +"head = document.getElementsByTagName('head')[0],"
                    +"style = document.createElement('style');"

                    +"if (!window.counter) { window.counter = 1;} else  { window.counter ++;"
                    +"if (window.counter % 2 == 0) { var css ='html {-webkit-filter: invert(0%); -moz-filter:    invert(0%); -o-filter: invert(0%); -ms-filter: invert(0%); }'}"
                    +"};"

                    +"style.type = 'text/css';"
                    +"if (style.styleSheet){"
                    +"style.styleSheet.cssText = css;"
                    +"} else {"
                    +"style.appendChild(document.createTextNode(css));"
                    +"}"

                    //injecting the css to the head
                    +"head.appendChild(style);"
                    +"}());";

                    CustomWebView.this.loadUrl(js);

Upvotes: 3

ken.yk.hung
ken.yk.hung

Reputation: 76

Ok, this is not in document, and not recommended, but it will work:

@Override
protected void onCreate(Bundle savedInstanceState) {
    ...
    webview.loadUrl("http://en.wikipedia.org/wiki/Lena_S%C3%B6derberg");
    try {
        Class clsWebSettingsClassic = 
            getClassLoader().loadClass("android.webkit.WebSettingsClassic");
        Method md = clsWebSettingsClassic.getMethod(
                "setProperty", String.class, String.class);
        md.invoke(webview.getSettings(), "inverted", "true");
        md.invoke(webview.getSettings(), "inverted_contrast", "1");
    } catch (Exception e) {}
}

This will do inverted rendering to WebView.
The range of "inverted_contrast" is about 1 to 30 (not very sure).
The result tested with android 4.2:

https://i.sstatic.net/GsKjX.png

Upvotes: 2

Lokesh
Lokesh

Reputation: 5378

Use this for webview backgroundColor:

   import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.webkit.WebView;

public class MainActivity extends Activity {

    WebView webview1;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        webview1=(WebView)findViewById(R.id.webview1);

        String text = "<html><head>"
                  + "<style type=\"text/css\">body{color: #fff; background-color: #000;}"
                  + "</style></head>"
                  + "<body>"                          
                  + "Helloo Andorid"
                  + "</body></html>";

        webview1.loadData(text, "text/html", "utf-8");
        webview1.setBackgroundColor(00000000);
    }

}

It's works for me..

Upvotes: 0

Ali Ahmad
Ali Ahmad

Reputation: 1351

in XML

<WebView
            android:id="@+id/web"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:background="@android:color/black" />

in java code

String str="<div style=\'background-color:transparent;padding: 5px ;color:#white'>Enter text to display in web view</div";
WebView web=(WebView)findViewById(R.id.web);
web.loadData(str,"text/html","utf-8");
web.setBackgroundColor(Color.TRANSPARENT);

Upvotes: 1

Bebin T.N
Bebin T.N

Reputation: 2649

Hai this may help you

dialogMesage.setBackgroundColor(0x00000000);

or

myWebView.setBackgroundColor(Color.parseColor("#FFFFFF"));

Upvotes: 0

Exceptional
Exceptional

Reputation: 3004

Give the following in java class

webView1.setBackgroundColor(0);

and set the colour of text in xml

Upvotes: 1

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