アンドロイドエリプサイズマルチテキストビュー

複数行のテキストビューを楕円化する必要があります。私のコンポーネントは、楕円で少なくとも4行を表示するのに十分な大きさですが、2行しか表示されません。コンポーネントの行の最小数と最大数を変更しようとしましたが、何も変更されません。

これが問題の解決策です。これは、楕円化に実際に機能するTextViewのサブクラスです。以前の回答にリストされているandroid-textview-multiline-ellipseコードは、特定の状況でバグがあり、GPLにあるため、ほとんどの人にとって実際には機能しません。このコードを自由に帰属せずに、または必要に応じてApacheライセンスの下で自由に使用してください。テキストが省略記号になったときに通知するリスナーがあることに注意してください。

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
    }
}

私のアプリでも同様の問題がありました。2行の文字列で、文字列が長すぎる場合は最終的に「...」を追加しました。私はこのコードをxmlファイルでtextviewタグに使用しました：

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

私もこの問題に遭遇しました。未解決のままのかなり古いバグがあります：バグ2254

これを試してみてください、それは私にとってはうまくいきます、私は4行あり、最後の4行目の最後に「...」を追加します。それは士気の答えと同じですが、そこにsingeLine = "false"があります。

<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!" />

この問題を解決し、最後に、私は自分自身で短い解決策を構築します。必要な行を手動で楕円形にすると、maxLine属性によってテキストがカットされます。

この例では、テキストを最大3行にカットします

        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);
                }

            }
        });

Micah Hainline、Alex Băluț、Paul Imhoffのソリューションを組み合わせて、テキストTextViewもサポートする楕円化マルチラインを作成しましたSpanned。

android:ellipsizeとを設定するだけです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);
        }
    }
}

完全なソース：EllipsizingTextView.java

私の場合、これをJavaでコーディングする必要はありません。すべてが期待どおりに機能します。などの必要はありません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" />

しかし、Android Studio（v3.0）のレイアウトプレビューにはバグがあるようです。

私のデバイス上のAndroid 7.1.1を考えると、これは機能しています：

Micah Hainlineによる解決策とalebsのコメントに基づいて、スパンドテキストで機能する次のアプローチを採用しましたmyTextView.setText(Html.fromHtml("<b>Testheader</b> - Testcontent"));。これはSpanned現時点でのみ機能することに注意してください。それは多分で動作するように変更することができString、およびSpannedいずれかの方法。

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
      }
}

興味のある方のために、Micahの素敵なソリューションのC＃Xamarin.Androidポートを以下に示します。

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 
        { 
        }
    }
}

...2行目の最後に追加するには、テキストが短い場合に1行を保存します。

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

アクティビティにコードを追加するだけです

Textview.setEllipsize(TextUtils.TruncateAt.END)

これにより、テキストビューの最後に省略記号が追加されます

TextViewを拡張し、これらのメソッドをオーバーライドします。

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();
    }

}

これが私の解決策です。デモはgithubからダウンロードできます。 https://github.com/krossford/KrossLib/tree/master/android-project

このスクリーンショットはデモだったのでmaxLines = 4、うまく機能すると思います。

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;
    }
}

私は同じ問題を抱えています。android：ellipsize = "marquee"を削除するだけで修正しました

コードは非常にうまくいきました！Textだけを変更する必要がない場合は、onSizeChangedメソッドをオーバーロードできます。

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

これは私のhtmlも処理しました、

/*
 * 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;
    }
}

Orignal Source リンク

Micah Hainlineからのここでのトップの回答はうまくいきますが、Micahsの回答の下のコメントに投稿したユーザーalebによって作成されたライブラリはさらに優れています。

このコンポーネントを使用してAndroidライブラリを作成し、可能な限り多くのテキスト行を表示し、最後の行を省略できるように変更しました。github.com/triposo/baroneを参照してください

さらにいくつかの機能があります。TextViewだけが必要な場合は、ここにあります。

多分これは私がしたよりも早く他の人がそれを見つけるのを助けるでしょう:-)

これは遅いですが、ストックメールアプリで使用されているAndroidからのApacheライセンスクラスを見つけました：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;
    }
}