wielowierszowy widok tekstu w systemie Android

Muszę zmienić wielokropek na widok tekstu z wieloma wierszami. Mój komponent jest wystarczająco duży, aby wyświetlić co najmniej 4 linie z elipsą, ale wyświetlane są tylko 2 linie. Próbowałem zmienić minimalną i maksymalną liczbę wierszy komponentu, ale nic to nie zmienia.

Oto rozwiązanie problemu. Jest to podklasa TextView, która faktycznie działa w przypadku elipsy. W kodzie android-textview-multiline-ellipse wymienionym we wcześniejszej odpowiedzi stwierdziłem, że w pewnych okolicznościach zawiera błędy, a także podlega licencji GPL, która tak naprawdę nie działa dla większości z nas. Zapraszam do swobodnego używania tego kodu bez uznania autorstwa lub w ramach licencji Apache, jeśli wolisz. Zwróć uwagę, że istnieje słuchacz, który powiadamia Cię, gdy tekst stanie się wielokropkiem, co sam uznałem za całkiem przydatne.

import java.util.ArrayList;
import java.util.List;

import android.content.Context;
import android.graphics.Canvas;
import android.text.Layout;
import android.text.Layout.Alignment;
import android.text.StaticLayout;
import android.text.TextUtils.TruncateAt;
import android.util.AttributeSet;
import android.widget.TextView;

public class EllipsizingTextView extends TextView {
    private static final String ELLIPSIS = "...";

    public interface EllipsizeListener {
        void ellipsizeStateChanged(boolean ellipsized);
    }

    private final List<EllipsizeListener> ellipsizeListeners = new ArrayList<EllipsizeListener>();
    private boolean isEllipsized;
    private boolean isStale;
    private boolean programmaticChange;
    private String fullText;
    private int maxLines = -1;
    private float lineSpacingMultiplier = 1.0f;
    private float lineAdditionalVerticalPadding = 0.0f;

    public EllipsizingTextView(Context context) {
        super(context);
    }

    public EllipsizingTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public EllipsizingTextView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    public void addEllipsizeListener(EllipsizeListener listener) {
        if (listener == null) {
            throw new NullPointerException();
        }
        ellipsizeListeners.add(listener);
    }

    public void removeEllipsizeListener(EllipsizeListener listener) {
        ellipsizeListeners.remove(listener);
    }

    public boolean isEllipsized() {
        return isEllipsized;
    }

    @Override
    public void setMaxLines(int maxLines) {
        super.setMaxLines(maxLines);
        this.maxLines = maxLines;
        isStale = true;
    }

    public int getMaxLines() {
        return maxLines;
    }

    @Override
    public void setLineSpacing(float add, float mult) {
        this.lineAdditionalVerticalPadding = add;
        this.lineSpacingMultiplier = mult;
        super.setLineSpacing(add, mult);
    }

    @Override
    protected void onTextChanged(CharSequence text, int start, int before, int after) {
        super.onTextChanged(text, start, before, after);
        if (!programmaticChange) {
            fullText = text.toString();
            isStale = true;
        }
    }

    @Override
    protected void onDraw(Canvas canvas) {
        if (isStale) {
            super.setEllipsize(null);
            resetText();
        }
        super.onDraw(canvas);
    }

    private void resetText() {
        int maxLines = getMaxLines();
        String workingText = fullText;
        boolean ellipsized = false;
        if (maxLines != -1) {
            Layout layout = createWorkingLayout(workingText);
            if (layout.getLineCount() > maxLines) {
                workingText = fullText.substring(0, layout.getLineEnd(maxLines - 1)).trim();
                while (createWorkingLayout(workingText + ELLIPSIS).getLineCount() > maxLines) {
                    int lastSpace = workingText.lastIndexOf(' ');
                    if (lastSpace == -1) {
                        break;
                    }
                    workingText = workingText.substring(0, lastSpace);
                }
                workingText = workingText + ELLIPSIS;
                ellipsized = true;
            }
        }
        if (!workingText.equals(getText())) {
            programmaticChange = true;
            try {
                setText(workingText);
            } finally {
                programmaticChange = false;
            }
        }
        isStale = false;
        if (ellipsized != isEllipsized) {
            isEllipsized = ellipsized;
            for (EllipsizeListener listener : ellipsizeListeners) {
                listener.ellipsizeStateChanged(ellipsized);
            }
        }
    }

    private Layout createWorkingLayout(String workingText) {
        return new StaticLayout(workingText, getPaint(), getWidth() - getPaddingLeft() - getPaddingRight(),
                Alignment.ALIGN_NORMAL, lineSpacingMultiplier, lineAdditionalVerticalPadding, false);
    }

    @Override
    public void setEllipsize(TruncateAt where) {
        // Ellipsize settings are not respected
    }
}

W mojej aplikacji miałem podobny problem: 2 linie łańcucha i ostatecznie dodałem „...”, jeśli ciąg był za długi. Użyłem tego kodu w pliku xml do tagu textview:

android:maxLines="2"
android:ellipsize="end"
android:singleLine="false"

Też napotkałem ten problem. Jest w tym dość stary błąd, który pozostaje bez odpowiedzi: błąd 2254

Spróbuj tego, to działa dla mnie, mam 4 linie i dodaje "..." na końcu ostatniej / czwartej linii. To to samo, co odpowiedź morale, ale mam tam singeLine = "false".

<TextView 
android:layout_width="fill_parent" 
android:layout_height="wrap_content" 
android:maxLines="4" 
android:ellipsize="marquee" 
android:singleLine="false" 
android:text="Hi make this a very long string that wraps at least 4 lines, seriously make it really really long so it gets cut off at the fourth line not joke.  Just do it!" />

Mam ten problem i na koniec buduję sobie krótkie rozwiązanie. Musisz tylko ręcznie elipsować żądaną linię, twój atrybut maxLine wycina twój tekst.

W tym przykładzie wycięto tekst na maksymalnie 3 linie

        final TextView title = (TextView)findViewById(R.id.text);
        title.setText("A really long text");
        ViewTreeObserver vto = title.getViewTreeObserver();
        vto.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {

            @Override
            public void onGlobalLayout() {
                ViewTreeObserver obs = title.getViewTreeObserver();
                obs.removeGlobalOnLayoutListener(this);
                if(title.getLineCount() > 3){
                    Log.d("","Line["+title.getLineCount()+"]"+title.getText());
                    int lineEndIndex = title.getLayout().getLineEnd(2);
                    String text = title.getText().subSequence(0, lineEndIndex-3)+"...";
                    title.setText(text);
                    Log.d("","NewText:"+text);
                }

            }
        });

Połączyłem rozwiązania Micaha Hainline'a, Alexa Băluța i Paula Imhoffa, aby stworzyć wielokropek, TextViewktóry obsługuje również Spannedtekst.

Wystarczy ustawić android:ellipsizei android:maxLines.

/*
 * Copyright (C) 2011 Micah Hainline
 * Copyright (C) 2012 Triposo
 * Copyright (C) 2013 Paul Imhoff
 * Copyright (C) 2014 Shahin Yousefi
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import android.annotation.SuppressLint;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.support.annotation.NonNull;
import android.text.Layout;
import android.text.Layout.Alignment;
import android.text.SpannableStringBuilder;
import android.text.Spanned;
import android.text.StaticLayout;
import android.text.TextUtils;
import android.text.TextUtils.TruncateAt;
import android.util.AttributeSet;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;
import java.util.regex.Pattern;

public class EllipsizingTextView extends TextView {
    private static final CharSequence ELLIPSIS = "\u2026";
    private static final Pattern DEFAULT_END_PUNCTUATION
            = Pattern.compile("[\\.!?,;:\u2026]*$", Pattern.DOTALL);
    private final List<EllipsizeListener> mEllipsizeListeners = new ArrayList<>();
    private EllipsizeStrategy mEllipsizeStrategy;
    private boolean isEllipsized;
    private boolean isStale;
    private boolean programmaticChange;
    private CharSequence mFullText;
    private int mMaxLines;
    private float mLineSpacingMult = 1.0f;
    private float mLineAddVertPad = 0.0f;

    private Pattern mEndPunctPattern;

    public EllipsizingTextView(Context context) {
        this(context, null);
    }


    public EllipsizingTextView(Context context, AttributeSet attrs) {
        this(context, attrs, android.R.attr.textViewStyle);
    }


    public EllipsizingTextView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        TypedArray a = context.obtainStyledAttributes(attrs,
                new int[]{ android.R.attr.maxLines }, defStyle, 0);
        setMaxLines(a.getInt(0, Integer.MAX_VALUE));
        a.recycle();
        setEndPunctuationPattern(DEFAULT_END_PUNCTUATION);
    }

    public void setEndPunctuationPattern(Pattern pattern) {
        mEndPunctPattern = pattern;
    }

    public void addEllipsizeListener(@NonNull EllipsizeListener listener) {
        mEllipsizeListeners.add(listener);
    }

    public void removeEllipsizeListener(EllipsizeListener listener) {
        mEllipsizeListeners.remove(listener);
    }

    public boolean isEllipsized() {
        return isEllipsized;
    }

    @SuppressLint("Override")
    public int getMaxLines() {
        return mMaxLines;
    }

    @Override
    public void setMaxLines(int maxLines) {
        super.setMaxLines(maxLines);
        mMaxLines = maxLines;
        isStale = true;
    }

    public boolean ellipsizingLastFullyVisibleLine() {
        return mMaxLines == Integer.MAX_VALUE;
    }

    @Override
    public void setLineSpacing(float add, float mult) {
        mLineAddVertPad = add;
        mLineSpacingMult = mult;
        super.setLineSpacing(add, mult);
    }

    @Override
    public void setText(CharSequence text, BufferType type) {
        if (!programmaticChange) {
            mFullText = text;
            isStale = true;
        }
        super.setText(text, type);
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        if (ellipsizingLastFullyVisibleLine()) isStale = true;
    }

    @Override
    public void setPadding(int left, int top, int right, int bottom) {
        super.setPadding(left, top, right, bottom);
        if (ellipsizingLastFullyVisibleLine()) isStale = true;
    }

    @Override
    protected void onDraw(@NonNull Canvas canvas) {
        if (isStale) resetText();
        super.onDraw(canvas);
    }

    private void resetText() {
        int maxLines = getMaxLines();
        CharSequence workingText = mFullText;
        boolean ellipsized = false;

        if (maxLines != -1) {
            if (mEllipsizeStrategy == null) setEllipsize(null);
            workingText = mEllipsizeStrategy.processText(mFullText);
            ellipsized = !mEllipsizeStrategy.isInLayout(mFullText);
        }

        if (!workingText.equals(getText())) {
            programmaticChange = true;
            try {
                setText(workingText);
            } finally {
                programmaticChange = false;
            }
        }

        isStale = false;
        if (ellipsized != isEllipsized) {
            isEllipsized = ellipsized;
            for (EllipsizeListener listener : mEllipsizeListeners) {
                listener.ellipsizeStateChanged(ellipsized);
            }
        }
    }

    @Override
    public void setEllipsize(TruncateAt where) {
        if (where == null) {
            mEllipsizeStrategy = new EllipsizeNoneStrategy();
            return;
        }

        switch (where) {
            case END:
                mEllipsizeStrategy = new EllipsizeEndStrategy();
                break;
            case START:
                mEllipsizeStrategy = new EllipsizeStartStrategy();
                break;
            case MIDDLE:
                mEllipsizeStrategy = new EllipsizeMiddleStrategy();
                break;
            case MARQUEE:
                super.setEllipsize(where);
                isStale = false;
            default:
                mEllipsizeStrategy = new EllipsizeNoneStrategy();
                break;
        }
    }

    public interface EllipsizeListener {
        void ellipsizeStateChanged(boolean ellipsized);
    }

    private abstract class EllipsizeStrategy {
        public CharSequence processText(CharSequence text) {
            return !isInLayout(text) ? createEllipsizedText(text) : text;
        }

        public boolean isInLayout(CharSequence text) {
            Layout layout = createWorkingLayout(text);
            return layout.getLineCount() <= getLinesCount();
        }

        protected Layout createWorkingLayout(CharSequence workingText) {
            return new StaticLayout(workingText, getPaint(),
                    getMeasuredWidth() - getPaddingLeft() - getPaddingRight(),
                    Alignment.ALIGN_NORMAL, mLineSpacingMult,
                    mLineAddVertPad, false /* includepad */);
        }

        protected int getLinesCount() {
            if (ellipsizingLastFullyVisibleLine()) {
                int fullyVisibleLinesCount = getFullyVisibleLinesCount();
                return fullyVisibleLinesCount == -1 ? 1 : fullyVisibleLinesCount;
            } else {
                return mMaxLines;
            }
        }

        protected int getFullyVisibleLinesCount() {
            Layout layout = createWorkingLayout("");
            int height = getHeight() - getCompoundPaddingTop() - getCompoundPaddingBottom();
            int lineHeight = layout.getLineBottom(0);
            return height / lineHeight;
        }

        protected abstract CharSequence createEllipsizedText(CharSequence fullText);
    }

    private class EllipsizeNoneStrategy extends EllipsizeStrategy {
        @Override
        protected CharSequence createEllipsizedText(CharSequence fullText) {
            return fullText;
        }
    }

    private class EllipsizeEndStrategy extends EllipsizeStrategy {
        @Override
        protected CharSequence createEllipsizedText(CharSequence fullText) {
            Layout layout = createWorkingLayout(fullText);
            int cutOffIndex = layout.getLineEnd(mMaxLines - 1);
            int textLength = fullText.length();
            int cutOffLength = textLength - cutOffIndex;
            if (cutOffLength < ELLIPSIS.length()) cutOffLength = ELLIPSIS.length();
            String workingText = TextUtils.substring(fullText, 0, textLength - cutOffLength).trim();
            String strippedText = stripEndPunctuation(workingText);

            while (!isInLayout(strippedText + ELLIPSIS)) {
                int lastSpace = workingText.lastIndexOf(' ');
                if (lastSpace == -1) break;
                workingText = workingText.substring(0, lastSpace).trim();
                strippedText = stripEndPunctuation(workingText);
            }

            workingText = strippedText + ELLIPSIS;
            SpannableStringBuilder dest = new SpannableStringBuilder(workingText);

            if (fullText instanceof Spanned) {
                TextUtils.copySpansFrom((Spanned) fullText, 0, workingText.length(), null, dest, 0);
            }
            return dest;
        }

        public String stripEndPunctuation(CharSequence workingText) {
            return mEndPunctPattern.matcher(workingText).replaceFirst("");
        }
    }

    private class EllipsizeStartStrategy extends EllipsizeStrategy {
        @Override
        protected CharSequence createEllipsizedText(CharSequence fullText) {
            Layout layout = createWorkingLayout(fullText);
            int cutOffIndex = layout.getLineEnd(mMaxLines - 1);
            int textLength = fullText.length();
            int cutOffLength = textLength - cutOffIndex;
            if (cutOffLength < ELLIPSIS.length()) cutOffLength = ELLIPSIS.length();
            String workingText = TextUtils.substring(fullText, cutOffLength, textLength).trim();

            while (!isInLayout(ELLIPSIS + workingText)) {
                int firstSpace = workingText.indexOf(' ');
                if (firstSpace == -1) break;
                workingText = workingText.substring(firstSpace, workingText.length()).trim();
            }

            workingText = ELLIPSIS + workingText;
            SpannableStringBuilder dest = new SpannableStringBuilder(workingText);

            if (fullText instanceof Spanned) {
                TextUtils.copySpansFrom((Spanned) fullText, textLength - workingText.length(),
                        textLength, null, dest, 0);
            }
            return dest;
        }
    }

    private class EllipsizeMiddleStrategy extends EllipsizeStrategy {
        @Override
        protected CharSequence createEllipsizedText(CharSequence fullText) {
            Layout layout = createWorkingLayout(fullText);
            int cutOffIndex = layout.getLineEnd(mMaxLines - 1);
            int textLength = fullText.length();
            int cutOffLength = textLength - cutOffIndex;
            if (cutOffLength < ELLIPSIS.length()) cutOffLength = ELLIPSIS.length();
            cutOffLength += cutOffIndex % 2;    // Make it even.
            String firstPart = TextUtils.substring(
                    fullText, 0, textLength / 2 - cutOffLength / 2).trim();
            String secondPart = TextUtils.substring(
                    fullText, textLength / 2 + cutOffLength / 2, textLength).trim();

            while (!isInLayout(firstPart + ELLIPSIS + secondPart)) {
                int lastSpaceFirstPart = firstPart.lastIndexOf(' ');
                int firstSpaceSecondPart = secondPart.indexOf(' ');
                if (lastSpaceFirstPart == -1 || firstSpaceSecondPart == -1) break;
                firstPart = firstPart.substring(0, lastSpaceFirstPart).trim();
                secondPart = secondPart.substring(firstSpaceSecondPart, secondPart.length()).trim();
            }

            SpannableStringBuilder firstDest = new SpannableStringBuilder(firstPart);
            SpannableStringBuilder secondDest = new SpannableStringBuilder(secondPart);

            if (fullText instanceof Spanned) {
                TextUtils.copySpansFrom((Spanned) fullText, 0, firstPart.length(),
                        null, firstDest, 0);
                TextUtils.copySpansFrom((Spanned) fullText, textLength - secondPart.length(),
                        textLength, null, secondDest, 0);
            }
            return TextUtils.concat(firstDest, ELLIPSIS, secondDest);
        }
    }
}

Pełne źródło: EllipsizingTextView.java

W moim przypadku nie ma potrzeby kodowania tego w Javie. Wszystko działa zgodnie z oczekiwaniami. Nie potrzeba czegoś takiego android:singleLine="false".

<TextView
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:ellipsize="end"
  android:maxLines="4"
  android:text="@string/very_long_text" />

Ale wygląda na to, że w podglądzie układu Android Studio (v3.0) jest błąd:

Biorąc pod uwagę Androida 7.1.1 na moim urządzeniu, to działa:

Opierając się na rozwiązaniach Micaha Hainline'a i komentarza alebsa, wyszedłem z następującym podejściem, które działa z tekstami Spanned, więc np. myTextView.setText(Html.fromHtml("<b>Testheader</b> - Testcontent"));Działa! Zauważ, że działa to tylko Spannedteraz. Może być zmodyfikowany do pracy z Stringi Spannedtak czy inaczej.

public class EllipsizingTextView extends TextView {
    private static final Spanned ELLIPSIS = new SpannedString("…");

      public interface EllipsizeListener {
        void ellipsizeStateChanged(boolean ellipsized);
      }

      private final List<EllipsizeListener> ellipsizeListeners = new ArrayList<EllipsizeListener>();
      private boolean isEllipsized;
      private boolean isStale;
      private boolean programmaticChange;
      private Spanned fullText;
      private int maxLines;
      private float lineSpacingMultiplier = 1.0f;
      private float lineAdditionalVerticalPadding = 0.0f;

      public EllipsizingTextView(Context context) {
        this(context, null);
      }

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

      public EllipsizingTextView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        super.setEllipsize(null);
        TypedArray a = context.obtainStyledAttributes(attrs, new int[] { android.R.attr.maxLines });
        setMaxLines(a.getInt(0, Integer.MAX_VALUE));
      }

      public void addEllipsizeListener(EllipsizeListener listener) {
        if (listener == null) {
          throw new NullPointerException();
        }
        ellipsizeListeners.add(listener);
      }

      public void removeEllipsizeListener(EllipsizeListener listener) {
        ellipsizeListeners.remove(listener);
      }

      public boolean isEllipsized() {
        return isEllipsized;
      }

      @Override
      public void setMaxLines(int maxLines) {
        super.setMaxLines(maxLines);
        this.maxLines = maxLines;
        isStale = true;
      }

      public int getMaxLines() {
        return maxLines;
      }

      public boolean ellipsizingLastFullyVisibleLine() {
        return maxLines == Integer.MAX_VALUE;
      }

      @Override
      public void setLineSpacing(float add, float mult) {
        this.lineAdditionalVerticalPadding = add;
        this.lineSpacingMultiplier = mult;
        super.setLineSpacing(add, mult);
      }

      @Override
    public void setText(CharSequence text, BufferType type) {
          if (!programmaticChange && text instanceof Spanned) {
              fullText = (Spanned) text;
              isStale = true;
            }
        super.setText(text, type);
    }

      @Override
      protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        if (ellipsizingLastFullyVisibleLine()) {
          isStale = true;
        }
      }

      public void setPadding(int left, int top, int right, int bottom) {
        super.setPadding(left, top, right, bottom);
        if (ellipsizingLastFullyVisibleLine()) {
          isStale = true;
        }
      }

      @Override
      protected void onDraw(Canvas canvas) {
        if (isStale) {
          resetText();
        }
        super.onDraw(canvas);
      }

      private void resetText() {
        Spanned workingText = fullText;
        boolean ellipsized = false;
        Layout layout = createWorkingLayout(workingText);
        int linesCount = getLinesCount();
        if (layout.getLineCount() > linesCount) {
          // We have more lines of text than we are allowed to display.
          workingText = (Spanned) fullText.subSequence(0, layout.getLineEnd(linesCount - 1));
          while (createWorkingLayout((Spanned) TextUtils.concat(workingText, ELLIPSIS)).getLineCount() > linesCount) {
            int lastSpace = workingText.toString().lastIndexOf(' ');
            if (lastSpace == -1) {
              break;
            }
            workingText = (Spanned) workingText.subSequence(0, lastSpace);
          }
          workingText = (Spanned) TextUtils.concat(workingText, ELLIPSIS);
          ellipsized = true;
        }
        if (!workingText.equals(getText())) {
          programmaticChange = true;
          try {
            setText(workingText);
          } finally {
            programmaticChange = false;
          }
        }
        isStale = false;
        if (ellipsized != isEllipsized) {
          isEllipsized = ellipsized;
          for (EllipsizeListener listener : ellipsizeListeners) {
            listener.ellipsizeStateChanged(ellipsized);
          }
        }
      }

      /**
       * Get how many lines of text we are allowed to display.
       */
      private int getLinesCount() {
        if (ellipsizingLastFullyVisibleLine()) {
          int fullyVisibleLinesCount = getFullyVisibleLinesCount();
          if (fullyVisibleLinesCount == -1) {
            return 1;
          } else {
            return fullyVisibleLinesCount;
          }
        } else {
          return maxLines;
        }
      }

      /**
       * Get how many lines of text we can display so their full height is visible.
       */
      private int getFullyVisibleLinesCount() {
        Layout layout = createWorkingLayout(new SpannedString(""));
        int height = getHeight() - getPaddingTop() - getPaddingBottom();
        int lineHeight = layout.getLineBottom(0);
        return height / lineHeight;
      }

      private Layout createWorkingLayout(Spanned workingText) {
        return new StaticLayout(workingText, getPaint(),
            getWidth() - getPaddingLeft() - getPaddingRight(),
            Alignment.ALIGN_NORMAL, lineSpacingMultiplier,
            lineAdditionalVerticalPadding, false /* includepad */);
      }

      @Override
      public void setEllipsize(TruncateAt where) {
        // Ellipsize settings are not respected
      }
}

Dla zainteresowanych, oto port C # Xamarin.Android z pięknym rozwiązaniem Micaha:

public delegate void EllipsizeEvent(bool ellipsized);

public class EllipsizingTextView : TextView
{
    private const string Ellipsis = "...";

    public event EllipsizeEvent EllipsizeStateChanged;

    private bool isEllipsized;
    private bool isStale;
    private bool programmaticChange;
    private string fullText;
    private int maxLines = -1;
    private float lineSpacingMultiplier = 1.0f;
    private float lineAdditionalVerticalPadding;

    public EllipsizingTextView(Context context) : base(context) 
    {
    }

    public EllipsizingTextView(Context context, IAttributeSet attrs) : base(context, attrs) 
    {
    }

    public EllipsizingTextView(Context context, IAttributeSet attrs, int defStyle) : base(context, attrs, defStyle) 
    {
    }

    public EllipsizingTextView(IntPtr javaReference, JniHandleOwnership transfer) : base(javaReference, transfer)
    {
    }

    public bool IsEllipsized 
    {
        get { return isEllipsized; }
    }

    public override void SetMaxLines(int maxLines) {
        base.SetMaxLines(maxLines);
        this.maxLines = maxLines;
        isStale = true;
    }

    public int GetMaxLines() 
    {
        return maxLines;
    }

    public override void SetLineSpacing(float add, float mult) 
    {
        lineAdditionalVerticalPadding = add;
        lineSpacingMultiplier = mult;
        base.SetLineSpacing(add, mult);
    }

    protected override void OnTextChanged(ICharSequence text, int start, int before, int after) 
    {
        base.OnTextChanged(text, start, before, after);
        if (!programmaticChange) 
        {
            fullText = text.ToString();
            isStale = true;
        }
    }

    protected override void OnDraw(Canvas canvas) 
    {
        if (isStale) 
        {
            base.Ellipsize = null;
            ResetText();
        }
        base.OnDraw(canvas);
    }

    private void ResetText() 
    {
        int maxLines = GetMaxLines();
        string workingText = fullText;
        bool ellipsized = false;
        if (maxLines != -1) 
        {
            Layout layout = CreateWorkingLayout(workingText);
            if (layout.LineCount > maxLines) 
            {
                workingText = fullText.Substring(0, layout.GetLineEnd(maxLines - 1)).Trim();
                while (CreateWorkingLayout(workingText + Ellipsis).LineCount > maxLines) 
                {
                    int lastSpace = workingText.LastIndexOf(' ');
                    if (lastSpace == -1) 
                    {
                        break;
                    }
                    workingText = workingText.Substring(0, lastSpace);
                }
                workingText = workingText + Ellipsis;
                ellipsized = true;
            }
        }
        if (workingText != Text) 
        {
            programmaticChange = true;
            try 
            {
                Text = workingText;
            } 
            finally 
            {
                programmaticChange = false;
            }
        }
        isStale = false;
        if (ellipsized != isEllipsized) 
        {
            isEllipsized = ellipsized;
            if (EllipsizeStateChanged != null)
                EllipsizeStateChanged(ellipsized);
        }
    }

    private Layout CreateWorkingLayout(string workingText) 
    {
        return new StaticLayout(workingText, Paint, Width - PaddingLeft - PaddingRight, Layout.Alignment.AlignNormal, lineSpacingMultiplier, lineAdditionalVerticalPadding, false);
    }

    public override TextUtils.TruncateAt Ellipsize
    {
        get 
        { 
            return base.Ellipsize;
        }
        set 
        { 
        }
    }
}

Aby dodać ...koniec drugiej linii, zapisując 1 linię, jeśli tekst jest krótki:

android:maxLines="2"
android:ellipsize="end"

Po prostu dodaj kod w swojej aktywności

Textview.setEllipsize(TextUtils.TruncateAt.END)

spowoduje to dodanie wielokropka na końcu widoku tekstu

Rozszerz TextView i zastąp te metody:

CharSequence origText = "";
int maxLines = 2;

@Override
public void setText(CharSequence text, BufferType type) {
    super.setText(text, type);
    origText = text;
}

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

    CharSequence text = origText;
    onPreDraw();

    while(getLineCount() > maxLines) {
        text = text.subSequence(0, text.length()-1);
        super.setText(text + "...");
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        onPreDraw();
    }

}

To jest moje rozwiązanie. możesz pobrać demo na mój github. https://github.com/krossford/KrossLib/tree/master/android-project

Ten zrzut ekranu był pokazem maxLines = 4, który myślę, że działa dobrze.

package com.krosshuang.krosslib.lib.view;

import android.content.Context;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.widget.TextView;

import java.util.ArrayList;

/*
如何使用？
How to use it?

> 1.在xml或者java代码中常规使用
> 1.use it like other views on xml and java code.

> 2.[必须] setMaxLines 方法替代在xml中的 "android:maxLines" 属性
> 2.[must] call the setMaxLines method to instead of the xml property android:maxLines.

> 3.[可选] 注意调用 setMultilineEllipsizeMode() 方法，具体请查看注释
> 3.[option] you can invoke setMultilineEllipsizeMode method, but I have not implement it.

*/

/**
* android自己的TextView对多行ellipsize处理的不好
* Created by krosshuang on 2015/12/17.
*/
public class EllipsizeEndTextView extends TextView {

    private static final String LOG_TAG = "EllipsizeTextView";

    /** 每一行都有省略号 */
    //TODO 该特性待完成
    public static final int MODE_EACH_LINE = 1;

    /** 最后一行才有省略号 */
    public static final int MODE_LAST_LINE = 2;

    private static final String ELLIPSIZE = "...";


    private ArrayList<String> mTextLines = new ArrayList<String>();

    private CharSequence mSrcText = null;
    private int mMultilineEllipsizeMode = MODE_LAST_LINE;
    private int mMaxLines = 1;
    private boolean mNeedIgnoreTextChangeAndSelfInvoke = false;


    public EllipsizeEndTextView(Context context) {
        super(context);
    }

    public EllipsizeEndTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public EllipsizeEndTextView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    @Override
    protected void onTextChanged(CharSequence text, int start, int lengthBefore, int lengthAfter) {
        if (!mNeedIgnoreTextChangeAndSelfInvoke) {
            super.onTextChanged(text, start, lengthBefore, lengthAfter);
            mSrcText = text;
        }
    }

    @Override
    public void setMaxLines(int maxlines) {
        super.setMaxLines(maxlines);
        mMaxLines = maxlines;
    }

    public int getSupportedMaxLines() {
        return mMaxLines;
    }

    @Override
    protected void onDraw(Canvas canvas) {
        setVisibleText();
        super.onDraw(canvas);
        mNeedIgnoreTextChangeAndSelfInvoke = false;
    }

    private void setVisibleText() {

        if (mSrcText == null) {
            return;
        }

        //获得可使用的width get available width
        final int aw = getWidth() - getPaddingLeft() - getPaddingRight();

        String srcText = mSrcText.toString();

        //将原始的字符串先按原始数据中存在的换行符弄成多行字符串
        String[] lines = srcText.split("\n");
        //Log.i(LOG_TAG, "原始数据有: " + lines.length + " 行 " + Arrays.toString(lines));

        int maxLines = getSupportedMaxLines();

        //将原始文本分成几行后加入list
        mTextLines.clear();
        for (int i = 0; i < lines.length; i++) {
            mTextLines.add(lines[i]);
        }

        switch (mMultilineEllipsizeMode) {

            case MODE_EACH_LINE:
                break;

            default:
            case MODE_LAST_LINE:
                //开始遍历
                String eachLine = null;
                for (int i = 0; i < mTextLines.size() && i < maxLines - 1; i++) {

                    eachLine = mTextLines.get(i);

                    if (getPaint().measureText(eachLine, 0, eachLine.length()) > aw) {

                        //当前行超过可用宽度
                        boolean isOut = true;
                        int end = eachLine.length() - 1;
                        while (isOut) {
                            if (getPaint().measureText(eachLine.substring(0, end), 0, end) > aw) {
                                end--;
                            } else {
                                isOut = false;
                            }
                        }

                        mTextLines.set(i, eachLine.substring(0, end));  //当前行设置为裁剪后的
                        mTextLines.add(i + 1, eachLine.substring(end, eachLine.length()));  //将裁剪剩余的部分，加入下一行，刚好接下来发生的遍历就可以处理它，相当于一个递归

                    }
                }

                //遍历处理结束，所有的行都是在可用宽度以内的
                break;
        }

        //根据 maxLines 和 结果的行数，决定最小需要多少行
        int resultSize = Math.min(maxLines, mTextLines.size());

        //对最后一行做处理
        String lastLine = mTextLines.get(resultSize - 1);

        //最后一行有两种情况需要加...
        //1.最后一行数据本身很长，超过了可用宽度，那么裁剪后尾部加上...
        //2.最后一行不是很长，并没有超过可用宽度，但是它底下还有行没有显示，因此加上...
        if (getPaint().measureText(lastLine, 0, lastLine.length()) > aw || resultSize < mTextLines.size()) {

            boolean isOut = true;
            int end = lastLine.length();
            while (isOut) {
                if (getPaint().measureText(lastLine.substring(0, end) + ELLIPSIZE, 0, end + 3) > aw) {
                    end--;
                } else {
                    isOut = false;
                }
            }

            mTextLines.set(resultSize - 1, lastLine.substring(0, end) + ELLIPSIZE);
        }

        //开始构建结果
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i <  resultSize ; i++) {
            sb.append(mTextLines.get(i));
            if (i != resultSize - 1) {
                sb.append('\n');
            }
        }

        //构建完成，set
        if (sb.toString().equals(getText())) {
            return;
        } else {
            mNeedIgnoreTextChangeAndSelfInvoke = true;
            setText(sb.toString());
        }
    }

    /**
     * 设置ellipsize mode，暂时不支持
     * @deprecated
     * */
    public void setMultilineEllipsizeMode(int mode) {
        mMultilineEllipsizeMode = mode;
    }
}

Miałem ten sam problem. Naprawiłem to, usuwając po prostu androida: ellipsize = "marquee"

Kod działał bardzo dobrze! Możesz przeciążyć metodę onSizeChanged, jeśli nie tylko Text ma zostać zmieniony.

@Override
protected void onSizeChanged (int w, int h, int oldw, int oldh) {
    isStale = true;
    super.onSizeChanged(w, h, oldw, oldh);
}

Ten również obsłużył mój kod HTML,

/*
 * Copyright (C) 2013 Google Inc.
 * Licensed to The Android Open Source Project.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.mail.ui;

import android.content.Context;
import android.content.res.TypedArray;
import android.text.Layout;
import android.text.Layout.Alignment;
import android.text.SpannableStringBuilder;
import android.text.Spanned;
import android.text.StaticLayout;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.widget.TextView;
/**
 * A special MultiLine TextView that will apply ellipsize logic to only the last
 * line of text, such that the last line may be shorter than any previous lines.
 */
public class EllipsizedMultilineTextView extends TextView {
    public static final int ALL_AVAILABLE = -1;
    private int mMaxLines;

    public EllipsizedMultilineTextView(Context context) {
        super(context);
    }
    public EllipsizedMultilineTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context, attrs);
    }
    public EllipsizedMultilineTextView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init(context, attrs);
    }

    private final void init(Context context, AttributeSet attrs) {
        final TypedArray a = context.obtainStyledAttributes(attrs,
            new int[] { android.R.attr.maxLines });
        setMaxLines(a.getInt(0, 2));
    }
    @Override
    public void setMaxLines(int maxlines) {
        super.setMaxLines(maxlines);
        mMaxLines = maxlines;
    }
    /**
     * Ellipsize just the last line of text in this view and set the text to the
     * new ellipsized value.
     * @param text Text to set and ellipsize
     * @param avail available width in pixels for the last line
     * @param paint Paint that has the proper properties set to measure the text
     *            for this view
     * @return the {@link CharSequence} that was set on the {@link TextView}
     */
    public CharSequence setText(final CharSequence text, int avail) {
        if (text == null || text.length() == 0) {
            return text;
        }
        setEllipsize(null);
        setText(text);
        if (avail == ALL_AVAILABLE) {
            return text;
        }
        Layout layout = getLayout();
        if (layout == null) {
            final int w = getWidth() - getCompoundPaddingLeft() - getCompoundPaddingRight();
            layout = new StaticLayout(text, 0, text.length(), getPaint(), w, Alignment.ALIGN_NORMAL,
                1.0f, 0f, false);
        }
        // find the last line of text and chop it according to available space
        final int lastLineStart = layout.getLineStart(mMaxLines - 1);
        final CharSequence remainder = TextUtils.ellipsize(text.subSequence(lastLineStart,
            text.length()), getPaint(), avail, TextUtils.TruncateAt.END);
        // assemble just the text portion, without spans
        final SpannableStringBuilder builder = new SpannableStringBuilder();
        builder.append(text.toString(), 0, lastLineStart);
        if (!TextUtils.isEmpty(remainder)) {
            builder.append(remainder.toString());
        }
        // Now copy the original spans into the assembled string, modified for any ellipsizing.
        //
        // Merely assembling the Spanned pieces together would result in duplicate CharacterStyle
        // spans in the assembled version if a CharacterStyle spanned across the lastLineStart
        // offset.
        if (text instanceof Spanned) {
            final Spanned s = (Spanned) text;
            final Object[] spans = s.getSpans(0, s.length(), Object.class);
            final int destLen = builder.length();
            for (int i = 0; i < spans.length; i++) {
                final Object span = spans[i];
                final int start = s.getSpanStart(span);
                final int end = s.getSpanEnd(span);
                final int flags = s.getSpanFlags(span);
                if (start <= destLen) {
                    builder.setSpan(span, start, Math.min(end, destLen), flags);
                }
            }
        }
        setText(builder);
        return builder;
    }
}

Oryginalne źródło LINK

Najlepsza odpowiedź od Micah Hainline działa świetnie, ale jeszcze lepsza jest biblioteka, która została zbudowana na jej podstawie przez użytkownika aleb, który zamieścił w komentarzach pod odpowiedzią Micaha:

Stworzyłem bibliotekę Androida z tym komponentem i zmieniłem ją, aby móc wyświetlać jak najwięcej wierszy tekstu i elipsę ostatniej; zobacz github.com/triposo/barone

Jest w nim kilka innych funkcji, jeśli potrzebujesz tylko TextView, jest tutaj .

Może to pomoże innym znaleźć to szybciej niż ja :-)

To późno, ale znalazłem klasę na licencji Apache z Androida, która jest używana w aplikacji pocztowej: https://android.googlesource.com/platform/packages/apps/UnifiedEmail/+/184ec73/src/com/android/ mail / ui / EllipsizedMultilineTextView.java

/*
 * Copyright (C) 2013 Google Inc.
 * Licensed to The Android Open Source Project.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.android.mail.ui;
import android.content.Context;
import android.text.Layout;
import android.text.Layout.Alignment;
import android.text.SpannableStringBuilder;
import android.text.Spanned;
import android.text.StaticLayout;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.widget.TextView;
/**
 * A special MultiLine TextView that will apply ellipsize logic to only the last
 * line of text, such that the last line may be shorter than any previous lines.
 */
public class EllipsizedMultilineTextView extends TextView {
    public static final int ALL_AVAILABLE = -1;
    private int mMaxLines;
    public EllipsizedMultilineTextView(Context context) {
        this(context, null);
    }
    public EllipsizedMultilineTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }
    @Override
    public void setMaxLines(int maxlines) {
        super.setMaxLines(maxlines);
        mMaxLines = maxlines;
    }
    /**
     * Ellipsize just the last line of text in this view and set the text to the
     * new ellipsized value.
     * @param text Text to set and ellipsize
     * @param avail available width in pixels for the last line
     * @param paint Paint that has the proper properties set to measure the text
     *            for this view
     * @return the {@link CharSequence} that was set on the {@link TextView}
     */
    public CharSequence setText(final CharSequence text, int avail) {
        if (text == null || text.length() == 0) {
            return text;
        }
        setEllipsize(null);
        setText(text);
        if (avail == ALL_AVAILABLE) {
            return text;
        }
        Layout layout = getLayout();
        if (layout == null) {
            final int w = getWidth() - getCompoundPaddingLeft() - getCompoundPaddingRight();
            layout = new StaticLayout(text, 0, text.length(), getPaint(), w, Alignment.ALIGN_NORMAL,
                    1.0f, 0f, false);
        }
        // find the last line of text and chop it according to available space
        final int lastLineStart = layout.getLineStart(mMaxLines - 1);
        final CharSequence remainder = TextUtils.ellipsize(text.subSequence(lastLineStart,
                text.length()), getPaint(), avail, TextUtils.TruncateAt.END);
        // assemble just the text portion, without spans
        final SpannableStringBuilder builder = new SpannableStringBuilder();
        builder.append(text.toString(), 0, lastLineStart);
        if (!TextUtils.isEmpty(remainder)) {
            builder.append(remainder.toString());
        }
        // Now copy the original spans into the assembled string, modified for any ellipsizing.
        //
        // Merely assembling the Spanned pieces together would result in duplicate CharacterStyle
        // spans in the assembled version if a CharacterStyle spanned across the lastLineStart
        // offset.
        if (text instanceof Spanned) {
            final Spanned s = (Spanned) text;
            final Object[] spans = s.getSpans(0, s.length(), Object.class);
            final int destLen = builder.length();
            for (int i = 0; i < spans.length; i++) {
                final Object span = spans[i];
                final int start = s.getSpanStart(span);
                final int end = s.getSpanEnd(span);
                final int flags = s.getSpanFlags(span);
                if (start <= destLen) {
                    builder.setSpan(span, start, Math.min(end, destLen), flags);
                }
            }
        }
        setText(builder);
        return builder;
    }
}