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Android TextView Justify Text

开发者 https://www.devze.com 2023-02-16 03:24 出处:网络
How do you get the text of a TextView to be Justified (with text flush on the left- and right- hand sides)?

How do you get the text of a TextView to be Justified (with text flush on the left- and right- hand sides)?

I found a poss开发者_JAVA百科ible solution here, but it does not work (even if you change vertical-center to center_vertical, etc).


I do not believe Android supports full justification.

UPDATE 2018-01-01: Android 8.0+ supports justification modes with TextView.


The @CommonsWare answer is correct. Android 8.0+ does support "Full Justification" (or simply "Justification", as it is sometimes ambiguously referred to).

Android also supports "Flush Left/Right Text Alignment". See the wikipedia article on Justification for the distinction. Many people consider the concept of 'justification' to encompass full-justification as well as left/right text alignment, which is what they end up searching for when they want to do left/right text alignment. This answer explains how to achieve the left/right text alignment.

It is possible to achieve Flush Left/Right Text Alignment (as opposed to Full Justification, as the question is asking about). To demonstrate I will be using a basic 2-column form (labels in the left column and text fields in the right column) as an example. In this example the text in the labels in the left column will be right-aligned so they appear flush up against their text fields in the right column.

In the XML layout you can get the TextView elements themselves (the left column) to align to the right by adding the following attribute inside all of the TextViews:

<TextView
   ...
   android:layout_gravity="center_vertical|end">
   ...
</TextView>

However, if the text wraps to multiple lines, the text would still be flush left aligned inside the TextView. Adding the following attribute makes the actual text flush right aligned (ragged left) inside the TextView:

<TextView
   ...
   android:gravity="end">
   ...
</TextView>

So the gravity attribute specifies how to align the text inside the TextView layout_gravity specifies how to align/layout the TextView element itself.


TextView in Android O offers full justification (new typographic alignment) itself.
You just need to do this:

Kotlin

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
    textView.justificationMode = JUSTIFICATION_MODE_INTER_WORD
}

Java

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
    textView.setJustificationMode(JUSTIFICATION_MODE_INTER_WORD);
}

XML

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:justificationMode="inter_word" />

Default is JUSTIFICATION_MODE_NONE (none in xml).


To justify text in android I used WebView

    setContentView(R.layout.main);

    WebView view = new WebView(this);
    view.setVerticalScrollBarEnabled(false);

    ((LinearLayout)findViewById(R.id.inset_web_view)).addView(view);

    view.loadData(getString(R.string.hello), "text/html; charset=utf-8", "utf-8");

and html.

<string name="hello">
<![CDATA[
<html>
 <head></head>
 <body style="text-align:justify;color:gray;background-color:black;">
  Lorem ipsum dolor sit amet, consectetur 
  adipiscing elit. Nunc pellentesque, urna
  nec hendrerit pellentesque, risus massa
 </body>
</html>
]]>
</string>

I can't yet upload images to prove it but "it works for me".


UPDATED

We have created a simple class for this. There are currently two methods to achieve what you are looking for. Both require NO WEBVIEW and SUPPORTS SPANNABLES.

LIBRARY: https://github.com/bluejamesbond/TextJustify-Android

SUPPORTS: Android 2.0 to 5.X

SETUP

// Please visit Github for latest setup instructions.

SCREENSHOT

Android TextView Justify Text


You can use JustifiedTextView for Android project in github. this is a custom view that simulate justified text for you. It support Android 2.0+ and right to left languages.

Android TextView Justify Text


I write a widget base on native textview to do it.

github

Android TextView Justify Text


I found a way to solve this problem, but this may not be very grace, but the effect is not bad.

Its principle is to replace the spaces of each line to the fixed-width ImageSpan (the color is transparent).

public static void justify(final TextView textView) {

    final AtomicBoolean isJustify = new AtomicBoolean(false);

    final String textString = textView.getText().toString();

    final TextPaint textPaint = textView.getPaint();

    final SpannableStringBuilder builder = new SpannableStringBuilder();

    textView.post(new Runnable() {
        @Override
        public void run() {

            if (!isJustify.get()) {

                final int lineCount = textView.getLineCount();
                final int textViewWidth = textView.getWidth();

                for (int i = 0; i < lineCount; i++) {

                    int lineStart = textView.getLayout().getLineStart(i);
                    int lineEnd = textView.getLayout().getLineEnd(i);

                    String lineString = textString.substring(lineStart, lineEnd);

                    if (i == lineCount - 1) {
                        builder.append(new SpannableString(lineString));
                        break;
                    }

                    String trimSpaceText = lineString.trim();
                    String removeSpaceText = lineString.replaceAll(" ", "");

                    float removeSpaceWidth = textPaint.measureText(removeSpaceText);
                    float spaceCount = trimSpaceText.length() - removeSpaceText.length();

                    float eachSpaceWidth = (textViewWidth - removeSpaceWidth) / spaceCount;

                    SpannableString spannableString = new SpannableString(lineString);
                    for (int j = 0; j < trimSpaceText.length(); j++) {
                        char c = trimSpaceText.charAt(j);
                        if (c == ' ') {
                            Drawable drawable = new ColorDrawable(0x00ffffff);
                            drawable.setBounds(0, 0, (int) eachSpaceWidth, 0);
                            ImageSpan span = new ImageSpan(drawable);
                            spannableString.setSpan(span, j, j + 1, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
                        }
                    }

                    builder.append(spannableString);
                }

                textView.setText(builder);
                isJustify.set(true);
            }
        }
    });
}

I put the code on GitHub: https://github.com/twiceyuan/TextJustification

Overview:

Android TextView Justify Text


XML Layout: declare WebView instead of TextView

<WebView
 android:id="@+id/textContent"
 android:layout_width="fill_parent"
 android:layout_height="wrap_content" />

Java code: set text data to WebView

WebView view = (WebView) findViewById(R.id.textContent);
String text;
text = "<html><body><p align=\"justify\">";
text+= "This is the text will be justified when displayed!!!";
text+= "</p></body></html>";
view.loadData(text, "text/html", "utf-8");

This may Solve your problem. Its Fully worked for me.


Very Simple We can do that in the xml file

<TextView 
android:justificationMode="inter_word"
/>


Here's how I did it, I think the most elegant way I could. With this solution, the only things you need to do in your layouts are:

  • add an additional xmlns declaration
  • change your TextViews source text namespace from android to your new namespace
  • replace your TextViews with x.y.z.JustifiedTextView

Here's the code. Works perfectly fine on my phones (Galaxy Nexus Android 4.0.2, Galaxy Teos Android 2.1). Feel free, of course, to replace my package name with yours.

/assets/justified_textview.css:

body {
    font-size: 1.0em;
    color: rgb(180,180,180);
    text-align: justify;
}

@media screen and (-webkit-device-pixel-ratio: 1.5) {
    /* CSS for high-density screens */
    body {
        font-size: 1.05em;
    }
}

@media screen and (-webkit-device-pixel-ratio: 2.0) {
    /* CSS for extra high-density screens */
    body {
        font-size: 1.1em;
    }
}

/res/values/attrs.xml:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="JustifiedTextView">
        <attr name="text" format="reference" />
    </declare-styleable>
</resources>

/res/layout/test.xml:

<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:myapp="http://schemas.android.com/apk/res/net.bicou.myapp"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical" >

        <net.bicou.myapp.widget.JustifiedTextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            myapp:text="@string/surv1_1" />

    </LinearLayout>
</ScrollView>

/src/net/bicou/myapp/widget/JustifiedTextView.java:

package net.bicou.myapp.widget;

import net.bicou.myapp.R;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Color;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.view.View;
import android.webkit.WebView;

public class JustifiedTextView extends WebView {
    public JustifiedTextView(final Context context) {
        this(context, null, 0);
    }

    public JustifiedTextView(final Context context, final AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public JustifiedTextView(final Context context, final AttributeSet attrs, final int defStyle) {
        super(context, attrs, defStyle);

        if (attrs != null) {
            final TypedValue tv = new TypedValue();
            final TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.JustifiedTextView, defStyle, 0);
            if (ta != null) {
                ta.getValue(R.styleable.JustifiedTextView_text, tv);

                if (tv.resourceId > 0) {
                    final String text = context.getString(tv.resourceId).replace("\n", "<br />");
                    loadDataWithBaseURL("file:///android_asset/",
                            "<html><head>" +
                                    "<link rel=\"stylesheet\" type=\"text/css\" href=\"justified_textview.css\" />" +
                                    "</head><body>" + text + "</body></html>",

                                    "text/html", "UTF8", null);
                    setTransparentBackground();
                }
            }
        }
    }

    public void setTransparentBackground() {
        try {
            setLayerType(View.LAYER_TYPE_SOFTWARE, null);
        } catch (final NoSuchMethodError e) {
        }

        setBackgroundColor(Color.TRANSPARENT);
        setBackgroundDrawable(null);
        setBackgroundResource(0);
    }
}

We need to set the rendering to software in order to get transparent background on Android 3+. Hence the try-catch for older versions of Android.

Hope this helps!

PS: please not that it might be useful to add this to your whole activity on Android 3+ in order to get the expected behavior:
android:hardwareAccelerated="false"


While still not complete justified text, you can now balance line lengths using android:breakStrategy="balanced" from API 23 onwards

http://developer.android.com/reference/android/widget/TextView.html#attr_android:breakStrategy


I write my own class to solve this problem, Here it is Just you have to call the static justify function that takes two arguments

  1. Text View object
  2. Content Width (Total width of your text view)

//MainActivity

package com.fawad.textjustification;
import android.app.Activity;
import android.database.Cursor;
import android.graphics.Point;
import android.graphics.Typeface;
import android.os.Bundle;
import android.util.DisplayMetrics;
import android.view.Display;
import android.view.Gravity;
import android.view.Menu;
import android.widget.TextView;

public class MainActivity extends Activity {
    static Point size;
    static float density;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Display display = getWindowManager().getDefaultDisplay();
        size=new Point();
        DisplayMetrics dm=new DisplayMetrics();
        display.getMetrics(dm);
        density=dm.density;
        display.getSize(size);


        TextView tv=(TextView)findViewById(R.id.textView1);
        Typeface typeface=Typeface.createFromAsset(this.getAssets(), "Roboto-Medium.ttf");
        tv.setTypeface(typeface);
        tv.setLineSpacing(0f, 1.2f);
        tv.setTextSize(10*MainActivity.density);

        //some random long text
         String myText=getResources().getString(R.string.my_text);

         tv.setText(myText);
        TextJustification.justify(tv,size.x);


    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

}

//TextJustificationClass

package com.fawad.textjustification;

import java.util.ArrayList;

import android.graphics.Paint;
import android.text.TextUtils;
import android.widget.TextView;

public class TextJustification {

    public static void justify(TextView textView,float contentWidth) {
        String text=textView.getText().toString();
        Paint paint=textView.getPaint();

        ArrayList<String> lineList=lineBreak(text,paint,contentWidth);

        textView.setText(TextUtils.join(" ", lineList).replaceFirst("\\s", ""));
    }


    private static ArrayList<String> lineBreak(String text,Paint paint,float contentWidth){
        String [] wordArray=text.split("\\s"); 
        ArrayList<String> lineList = new ArrayList<String>();
        String myText="";

        for(String word:wordArray){
            if(paint.measureText(myText+" "+word)<=contentWidth)
                myText=myText+" "+word;
            else{
                int totalSpacesToInsert=(int)((contentWidth-paint.measureText(myText))/paint.measureText(" "));
                lineList.add(justifyLine(myText,totalSpacesToInsert));
                myText=word;
            }
        }
        lineList.add(myText);
        return lineList;
    }

    private static String justifyLine(String text,int totalSpacesToInsert){
        String[] wordArray=text.split("\\s");
        String toAppend=" ";

        while((totalSpacesToInsert)>=(wordArray.length-1)){
            toAppend=toAppend+" ";
            totalSpacesToInsert=totalSpacesToInsert-(wordArray.length-1);
        }
        int i=0;
        String justifiedText="";
        for(String word:wordArray){
            if(i<totalSpacesToInsert)
                justifiedText=justifiedText+word+" "+toAppend;

            else                
                justifiedText=justifiedText+word+toAppend;

            i++;
        }

        return justifiedText;
    }

}

//XML

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"

    tools:context=".MainActivity" 
    >



    <ScrollView
        android:id="@+id/scrollView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
         >

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical"

             >
            <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />
        </LinearLayout>
    </ScrollView>

</RelativeLayout>


FILL_HORIZONTAL is equivalent to CENTER_HORIZONTAL. You can see this code snippet in textview's source code:

case Gravity.CENTER_HORIZONTAL:
case Gravity.FILL_HORIZONTAL:
    return (mLayout.getLineWidth(0) - ((mRight - mLeft) -
            getCompoundPaddingLeft() - getCompoundPaddingRight())) /
            getHorizontalFadingEdgeLength();


There is a CustomView for this problem, this custom text view is support Justified Text View.

Loot at this: JustifiedTextView

import java.util.ArrayList;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Typeface;
import android.text.TextPaint;
import android.view.View;

public class JustifiedTextView extends View {
        String text;
        ArrayList<Line> linesCollection = new ArrayList<Line>();
        TextPaint textPaint;
        Typeface font;
        int textColor;
        float textSize = 42f, lineHeight = 57f, wordSpacing = 15f, lineSpacing = 15f;
        float onBirim, w, h;
        float leftPadding, rightPadding;

        public JustifiedTextView(Context context, String text) {
                super(context);
                this.text = text;
                init();
        }

        private void init() {
                textPaint = new TextPaint(Paint.ANTI_ALIAS_FLAG);
                textColor = Color.BLACK;
        }

        @Override
        protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
                super.onMeasure(widthMeasureSpec, heightMeasureSpec);

                if (font != null) {
                        font = Typeface.createFromAsset(getContext().getAssets(), "font/Trykker-Regular.ttf");
                        textPaint.setTypeface(font);
                }
                textPaint.setColor(textColor);

                int minw = getPaddingLeft() + getPaddingRight() + getSuggestedMinimumWidth();
                w = resolveSizeAndState(minw, widthMeasureSpec, 1);
                h = MeasureSpec.getSize(widthMeasureSpec);

                onBirim = 0.009259259f * w;
                lineHeight = textSize + lineSpacing;
                leftPadding = 3 * onBirim + getPaddingLeft();
                rightPadding = 3 * onBirim + getPaddingRight();

                textPaint.setTextSize(textSize);

                wordSpacing = 15f;
                Line lineBuffer = new Line();
                this.linesCollection.clear();
                String[] lines = text.split("\n");
                for (String line : lines) {
                        String[] words = line.split(" ");
                        lineBuffer = new Line();
                        float lineWidth = leftPadding + rightPadding;
                        float totalWordWidth = 0;
                        for (String word : words) {
                                float ww = textPaint.measureText(word) + wordSpacing;
                                if (lineWidth + ww + (lineBuffer.getWords().size() * wordSpacing) > w) {// is
                                        lineBuffer.addWord(word);
                                        totalWordWidth += textPaint.measureText(word);
                                        lineBuffer.setSpacing((w - totalWordWidth - leftPadding - rightPadding) / (lineBuffer.getWords().size() - 1));
                                        this.linesCollection.add(lineBuffer);
                                        lineBuffer = new Line();
                                        totalWordWidth = 0;
                                        lineWidth = leftPadding + rightPadding;
                                } else {
                                        lineBuffer.setSpacing(wordSpacing);
                                        lineBuffer.addWord(word);
                                        totalWordWidth += textPaint.measureText(word);
                                        lineWidth += ww;
                                }
                        }
                        this.linesCollection.add(lineBuffer);
                }
                setMeasuredDimension((int) w, (int) ((this.linesCollection.size() + 1) * lineHeight + (10 * onBirim)));
        }

        @Override
        protected void onDraw(Canvas canvas) {
                super.onDraw(canvas);
                canvas.drawLine(0f, 10f, getMeasuredWidth(), 10f, textPaint);
                float x, y = lineHeight + onBirim;
                for (Line line : linesCollection) {
                        x = leftPadding;
                        for (String s : line.getWords()) {
                                canvas.drawText(s, x, y, textPaint);
                                x += textPaint.measureText(s) + line.spacing;
                        }
                        y += lineHeight;
                }
        }

        public String getText() {
                return text;
        }

        public void setText(String text) {
                this.text = text;
        }

        public Typeface getFont() {
                return font;
        }

        public void setFont(Typeface font) {
                this.font = font;
        }

        public float getLineHeight() {
                return lineHeight;
        }

        public void setLineHeight(float lineHeight) {
                this.lineHeight = lineHeight;
        }

        public float getLeftPadding() {
                return leftPadding;
        }

        public void setLeftPadding(float leftPadding) {
                this.leftPadding = leftPadding;
        }

        public float getRightPadding() {
                return rightPadding;
        }

        public void setRightPadding(float rightPadding) {
                this.rightPadding = rightPadding;
        }

        public void setWordSpacing(float wordSpacing) {
                this.wordSpacing = wordSpacing;
        }

        public float getWordSpacing() {
                return wordSpacing;
        }

        public float getLineSpacing() {
                return lineSpacing;
        }

        public void setLineSpacing(float lineSpacing) {
                this.lineSpacing = lineSpacing;
        }

        class Line {
                ArrayList<String> words = new ArrayList<String>();
                float spacing = 15f;

                public Line() {
                }

                public Line(ArrayList<String> words, float spacing) {
                        this.words = words;
                        this.spacing = spacing;
                }

                public void setSpacing(float spacing) {
                        this.spacing = spacing;
                }

                public float getSpacing() {
                        return spacing;
                }

                public void addWord(String s) {
                        words.add(s);
                }

                public ArrayList<String> getWords() {
                        return words;
                }
        }
}

Add above class to your src folder and use this sample code to add to your layout:

JustifiedTextView jtv= new JustifiedTextView(getApplicationContext(), "Lorem ipsum dolor sit amet... ");
LinearLayout place = (LinearLayout) findViewById(R.id.book_profile_content);
place.addView(jtv);


see here in the github

Just import the two files "TextJustifyUtils.java" and "TextViewEx.java" in your project.

public class TextJustifyUtils {
    // Please use run(...) instead
    public static void justify(TextView textView) {
        Paint paint = new Paint();

        String[] blocks;
        float spaceOffset = 0;
        float textWrapWidth = 0;

        int spacesToSpread;
        float wrappedEdgeSpace;
        String block;
        String[] lineAsWords;
        String wrappedLine;
        String smb = "";
        Object[] wrappedObj;

        // Pull widget properties
        paint.setColor(textView.getCurrentTextColor());
        paint.setTypeface(textView.getTypeface());
        paint.setTextSize(textView.getTextSize());

        textWrapWidth = textView.getWidth();
        spaceOffset = paint.measureText(" ");
        blocks = textView.getText().toString().split("((?<=\n)|(?=\n))");

        if (textWrapWidth < 20) {
            return;
        }

        for (int i = 0; i < blocks.length; i++) {
            block = blocks[i];

            if (block.length() == 0) {
                continue;
            } else if (block.equals("\n")) {
                smb += block;
                continue;
            }

            block = block.trim();

            if (block.length() == 0)
                continue;

            wrappedObj = TextJustifyUtils.createWrappedLine(block, paint,
                    spaceOffset, textWrapWidth);
            wrappedLine = ((String) wrappedObj[0]);
            wrappedEdgeSpace = (Float) wrappedObj[1];
            lineAsWords = wrappedLine.split(" ");
            spacesToSpread = (int) (wrappedEdgeSpace != Float.MIN_VALUE ? wrappedEdgeSpace
                    / spaceOffset
                    : 0);

            for (String word : lineAsWords) {
                smb += word + " ";

                if (--spacesToSpread > 0) {
                    smb += " ";
                }
            }

            smb = smb.trim();

            if (blocks[i].length() > 0) {
                blocks[i] = blocks[i].substring(wrappedLine.length());

                if (blocks[i].length() > 0) {
                    smb += "\n";
                }

                i--;
            }
        }

        textView.setGravity(Gravity.LEFT);
        textView.setText(smb);
    }

    protected static Object[] createWrappedLine(String block, Paint paint,
            float spaceOffset, float maxWidth) {
        float cacheWidth = maxWidth;
        float origMaxWidth = maxWidth;

        String line = "";

        for (String word : block.split("\\s")) {
            cacheWidth = paint.measureText(word);
            maxWidth -= cacheWidth;

            if (maxWidth <= 0) {
                return new Object[] { line, maxWidth + cacheWidth + spaceOffset };
            }

            line += word + " ";
            maxWidth -= spaceOffset;

        }

        if (paint.measureText(block) <= origMaxWidth) {
            return new Object[] { block, Float.MIN_VALUE };
        }

        return new Object[] { line, maxWidth };
    }

    final static String SYSTEM_NEWLINE = "\n";
    final static float COMPLEXITY = 5.12f; // Reducing this will increase
                                            // efficiency but will decrease
                                            // effectiveness
    final static Paint p = new Paint();

    public static void run(final TextView tv, float origWidth) {
        String s = tv.getText().toString();
        p.setTypeface(tv.getTypeface());
        String[] splits = s.split(SYSTEM_NEWLINE);
        float width = origWidth - 5;
        for (int x = 0; x < splits.length; x++)
            if (p.measureText(splits[x]) > width) {
                splits[x] = wrap(splits[x], width, p);
                String[] microSplits = splits[x].split(SYSTEM_NEWLINE);
                for (int y = 0; y < microSplits.length - 1; y++)
                    microSplits[y] = justify(removeLast(microSplits[y], " "),
                            width, p);
                StringBuilder smb_internal = new StringBuilder();
                for (int z = 0; z < microSplits.length; z++)
                    smb_internal.append(microSplits[z]
                            + ((z + 1 < microSplits.length) ? SYSTEM_NEWLINE
                                    : ""));
                splits[x] = smb_internal.toString();
            }
        final StringBuilder smb = new StringBuilder();
        for (String cleaned : splits)
            smb.append(cleaned + SYSTEM_NEWLINE);
        tv.setGravity(Gravity.LEFT);
        tv.setText(smb);
    }

    private static String wrap(String s, float width, Paint p) {
        String[] str = s.split("\\s"); // regex
        StringBuilder smb = new StringBuilder(); // save memory
        smb.append(SYSTEM_NEWLINE);
        for (int x = 0; x < str.length; x++) {
            float length = p.measureText(str[x]);
            String[] pieces = smb.toString().split(SYSTEM_NEWLINE);
            try {
                if (p.measureText(pieces[pieces.length - 1]) + length > width)
                    smb.append(SYSTEM_NEWLINE);
            } catch (Exception e) {
            }
            smb.append(str[x] + " ");
        }
        return smb.toString().replaceFirst(SYSTEM_NEWLINE, "");
    }

    private static String removeLast(String s, String g) {
        if (s.contains(g)) {
            int index = s.lastIndexOf(g);
            int indexEnd = index + g.length();
            if (index == 0)
                return s.substring(1);
            else if (index == s.length() - 1)
                return s.substring(0, index);
            else
                return s.substring(0, index) + s.substring(indexEnd);
        }
        return s;
    }

    private static String justifyOperation(String s, float width, Paint p) {
        float holder = (float) (COMPLEXITY * Math.random());
        while (s.contains(Float.toString(holder)))
            holder = (float) (COMPLEXITY * Math.random());
        String holder_string = Float.toString(holder);
        float lessThan = width;
        int timeOut = 100;
        int current = 0;
        while (p.measureText(s) < lessThan && current < timeOut) {
            s = s.replaceFirst(" ([^" + holder_string + "])", " "
                    + holder_string + "$1");
            lessThan = p.measureText(holder_string) + lessThan
                    - p.measureText(" ");
            current++;
        }
        String cleaned = s.replaceAll(holder_string, " ");
        return cleaned;
    }

    private static String justify(String s, float width, Paint p) {
        while (p.measureText(s) < width) {
            s = justifyOperation(s, width, p);
        }
        return s;
    }
}

and

public class TextViewEx extends TextView {
    private Paint paint = new Paint();

    private String[] blocks;
    private float spaceOffset = 0;
    private float horizontalOffset = 0;
    private float verticalOffset = 0;
    private float horizontalFontOffset = 0;
    private float dirtyRegionWidth = 0;
    private boolean wrapEnabled = false;
    int left, top, right, bottom = 0;
    private Align _align = Align.LEFT;
    private float strecthOffset;
    private float wrappedEdgeSpace;
    private String block;
    private String wrappedLine;
    private String[] lineAsWords;
    private Object[] wrappedObj;

    private Bitmap cache = null;
    private boolean cacheEnabled = false;

    public TextViewEx(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        // set a minimum of left and right padding so that the texts are not too
        // close to the side screen
        // this.setPadding(10, 0, 10, 0);
    }

    public TextViewEx(Context context, AttributeSet attrs) {
        super(context, attrs);
        // this.setPadding(10, 0, 10, 0);
    }

    public TextViewEx(Context context) {
        super(context);
        // this.setPadding(10, 0, 10, 0);
    }

    @Override
    public void setPadding(int left, int top, int right, int bottom) {
        // TODO Auto-generated method stub
        super.setPadding(left + 10, top, right + 10, bottom);
    }

    @Override
    public void setDrawingCacheEnabled(boolean cacheEnabled) {
        this.cacheEnabled = cacheEnabled;
    }

    public void setText(String st, boolean wrap) {
        wrapEnabled = wrap;
        super.setText(st);
    }

    public void setTextAlign(Align align) {
        _align = align;
    }

    @SuppressLint("NewApi")
    @Override
    protected void onDraw(Canvas canvas) {
        // If wrap is disabled then,
        // request original onDraw
        if (!wrapEnabled) {
            super.onDraw(canvas);
            return;
        }

        // Active canas needs to be set
        // based on cacheEnabled
        Canvas activeCanvas = null;

        // Set the active canvas based on
        // whether cache is enabled
        if (cacheEnabled) {

            if (cache != null) {
                // Draw to the OS provided canvas
                // if the cache is not empty
                canvas.drawBitmap(cache, 0, 0, paint);
                return;
            } else {
                // Create a bitmap and set the activeCanvas
                // to the one derived from the bitmap
                cache = Bitmap.createBitmap(getWidth(), getHeight(),
                        Config.ARGB_4444);
                activeCanvas = new Canvas(cache);
            }
        } else {
            // Active canvas is the OS
            // provided canvas
            activeCanvas = canvas;
        }

        // Pull widget properties
        paint.setColor(getCurrentTextColor());
        paint.setTypeface(getTypeface());
        paint.setTextSize(getTextSize());
        paint.setTextAlign(_align);
        paint.setFlags(Paint.ANTI_ALIAS_FLAG);

        // minus out the paddings pixel
        dirtyRegionWidth = getWidth() - getPaddingLeft() - getPaddingRight();
        int maxLines = Integer.MAX_VALUE;
        int currentapiVersion = android.os.Build.VERSION.SDK_INT;
        if (currentapiVersion >= android.os.Build.VERSION_CODES.JELLY_BEAN) {
            maxLines = getMaxLines();
        }
        int lines = 1;
        blocks = getText().toString().split("((?<=\n)|(?=\n))");
        verticalOffset = horizontalFontOffset = getLineHeight() - 0.5f; // Temp
                                                                        // fix
        spaceOffset = paint.measureText(" ");

        for (int i = 0; i < blocks.length && lines <= maxLines; i++) {
            block = blocks[i];
            horizontalOffset = 0;

            if (block.length() == 0) {
                continue;
            } else if (block.equals("\n")) {
                verticalOffset += horizontalFontOffset;
                continue;
            }

            block = block.trim();

            if (block.length() == 0) {
                continue;
            }

            wrappedObj = TextJustifyUtils.createWrappedLine(block, paint,
                    spaceOffset, dirtyRegionWidth);

            wrappedLine = ((String) wrappedObj[0]);
            wrappedEdgeSpace = (Float) wrappedObj[1];
            lineAsWords = wrappedLine.split(" ");
            strecthOffset = wrappedEdgeSpace != Float.MIN_VALUE ? wrappedEdgeSpace
                    / (lineAsWords.length - 1)
                    : 0;

            for (int j = 0; j < lineAsWords.length; j++) {
                String word = lineAsWords[j];
                if (lines == maxLines && j == lineAsWords.length - 1) {
                    activeCanvas.drawText("...", horizontalOffset,
                            verticalOffset, paint);

                } else if (j == 0) {
                    // if it is the first word of the line, text will be drawn
                    // starting from right edge of textview
                    if (_align == Align.RIGHT) {
                        activeCanvas.drawText(word, getWidth()
                                - (getPaddingRight()), verticalOffset, paint);
                        // add in the paddings to the horizontalOffset
                        horizontalOffset += getWidth() - (getPaddingRight());
                    } else {
                        activeCanvas.drawText(word, getPaddingLeft(),
                                verticalOffset, paint);
                        horizontalOffset += getPaddingLeft();
                    }

                } else {
                    activeCanvas.drawText(word, horizontalOffset,
                            verticalOffset, paint);
                }
                if (_align == Align.RIGHT)
                    horizontalOffset -= paint.measureText(word) + spaceOffset
                            + strecthOffset;
                else
                    horizontalOffset += paint.measureText(word) + spaceOffset
                            + strecthOffset;
            }

            lines++;

            if (blocks[i].length() > 0) {
                blocks[i] = blocks[i].substring(wrappedLine.length());
                verticalOffset += blocks[i].length() > 0 ? horizontalFontOffset
                        : 0;
                i--;
            }
        }

        if (cacheEnabled) {
            // Draw the cache onto the OS provided
            // canvas.
            canvas.drawBitmap(cache, 0, 0, paint);
        }
    }
}

Now, if you use normal textView like:

<TextView
                android:id="@+id/original"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="@string/lorum_ipsum" />

Simply use

<yourpackagename.TextViewEx
                android:id="@+id/changed"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="@string/lorum_ipsum" />

Define a variable and set justify to be true,

TextViewEx changed = (TextViewEx) findViewById(R.id.changed);
changed.setText(getResources().getString(R.string.lorum_ipsum),true);


I think there are two options:

  • Use something like Pango that specializes in this via the NDK and render text to an OpenGL or other surface.

  • Use Paint.measureText() and friends to get the lengths of words and lay them out manually on a Canvas in a custom view.


Android does not yet support full justification. We can use Webview and justify HTML instead of using textview. It works so fine. If you guys not clear, feel free to ask me :)


You can use justificationMode as inter_word in xml. You have to remember that this attribute is available for api level 26 and higher. For that you can assign targetApi as o. The full code is given bellow

<com.google.android.material.textview.MaterialTextView
            ...
            android:justificationMode="inter_word"
            tools:targetApi="o" />


Please try this code for below 8.0

<TextView 
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_gravity="center_horizontal"
  android:gravity="center|start"/>


Just use this property in xml file

android:justificationMode="inter_word"


Simplay we can use android:justificationMode="inter_word"

 <TextView
 android:justificationMode="inter_word"
 android:id="@+id/messageTv"
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:layout_margin="@dimen/text_margin"
 android:paddingTop="15sp"
 android:textAppearance="@style/TextAppearance.Material3.TitleMedium" />
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