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    <p>As a mobile developer, I was sad to find nothing native that supports auto resizing. My searches did not turn up anything that worked for me and in the end, I spent the better half of my weekend and created my own auto resize text view. I will post the code here and hopefully it will be useful for someone else. </p> <p>This class uses a static layout with the text paint of the original text view to measure the height. From there, I step down by 2 font pixels and remeasure until I have a size that fits. At the end, if the text still does not fit, I append an ellipsis. I had requirements to animate the text and reuse views and this seems to work well on the devices I have and seems to run fast enough for me. </p> <pre><code>/** * DO WHAT YOU WANT TO PUBLIC LICENSE * Version 2, December 2004 * * Copyright (C) 2004 Sam Hocevar &lt;sam@hocevar.net&gt; * * Everyone is permitted to copy and distribute verbatim or modified * copies of this license document, and changing it is allowed as long * as the name is changed. * * DO WHAT YOU WANT TO PUBLIC LICENSE * TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION * * 0. You just DO WHAT YOU WANT TO. */ import android.content.Context; import android.text.Layout.Alignment; import android.text.StaticLayout; import android.text.TextPaint; import android.util.AttributeSet; import android.util.TypedValue; import android.widget.TextView; /** * Text view that auto adjusts text size to fit within the view. * If the text size equals the minimum text size and still does not * fit, append with an ellipsis. * * @author Chase Colburn * @since Apr 4, 2011 */ public class AutoResizeTextView extends TextView { // Minimum text size for this text view public static final float MIN_TEXT_SIZE = 20; // Interface for resize notifications public interface OnTextResizeListener { public void onTextResize(TextView textView, float oldSize, float newSize); } // Our ellipse string private static final String mEllipsis = "..."; // Registered resize listener private OnTextResizeListener mTextResizeListener; // Flag for text and/or size changes to force a resize private boolean mNeedsResize = false; // Text size that is set from code. This acts as a starting point for resizing private float mTextSize; // Temporary upper bounds on the starting text size private float mMaxTextSize = 0; // Lower bounds for text size private float mMinTextSize = MIN_TEXT_SIZE; // Text view line spacing multiplier private float mSpacingMult = 1.0f; // Text view additional line spacing private float mSpacingAdd = 0.0f; // Add ellipsis to text that overflows at the smallest text size private boolean mAddEllipsis = true; // Default constructor override public AutoResizeTextView(Context context) { this(context, null); } // Default constructor when inflating from XML file public AutoResizeTextView(Context context, AttributeSet attrs) { this(context, attrs, 0); } // Default constructor override public AutoResizeTextView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); mTextSize = getTextSize(); } /** * When text changes, set the force resize flag to true and reset the text size. */ @Override protected void onTextChanged(final CharSequence text, final int start, final int before, final int after) { mNeedsResize = true; // Since this view may be reused, it is good to reset the text size resetTextSize(); } /** * If the text view size changed, set the force resize flag to true */ @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { if (w != oldw || h != oldh) { mNeedsResize = true; } } /** * Register listener to receive resize notifications * @param listener */ public void setOnResizeListener(OnTextResizeListener listener) { mTextResizeListener = listener; } /** * Override the set text size to update our internal reference values */ @Override public void setTextSize(float size) { super.setTextSize(size); mTextSize = getTextSize(); } /** * Override the set text size to update our internal reference values */ @Override public void setTextSize(int unit, float size) { super.setTextSize(unit, size); mTextSize = getTextSize(); } /** * Override the set line spacing to update our internal reference values */ @Override public void setLineSpacing(float add, float mult) { super.setLineSpacing(add, mult); mSpacingMult = mult; mSpacingAdd = add; } /** * Set the upper text size limit and invalidate the view * @param maxTextSize */ public void setMaxTextSize(float maxTextSize) { mMaxTextSize = maxTextSize; requestLayout(); invalidate(); } /** * Return upper text size limit * @return */ public float getMaxTextSize() { return mMaxTextSize; } /** * Set the lower text size limit and invalidate the view * @param minTextSize */ public void setMinTextSize(float minTextSize) { mMinTextSize = minTextSize; requestLayout(); invalidate(); } /** * Return lower text size limit * @return */ public float getMinTextSize() { return mMinTextSize; } /** * Set flag to add ellipsis to text that overflows at the smallest text size * @param addEllipsis */ public void setAddEllipsis(boolean addEllipsis) { mAddEllipsis = addEllipsis; } /** * Return flag to add ellipsis to text that overflows at the smallest text size * @return */ public boolean getAddEllipsis() { return mAddEllipsis; } /** * Reset the text to the original size */ public void resetTextSize() { if (mTextSize &gt; 0) { super.setTextSize(TypedValue.COMPLEX_UNIT_PX, mTextSize); mMaxTextSize = mTextSize; } } /** * Resize text after measuring */ @Override protected void onLayout(boolean changed, int left, int top, int right, int bottom) { if (changed || mNeedsResize) { int widthLimit = (right - left) - getCompoundPaddingLeft() - getCompoundPaddingRight(); int heightLimit = (bottom - top) - getCompoundPaddingBottom() - getCompoundPaddingTop(); resizeText(widthLimit, heightLimit); } super.onLayout(changed, left, top, right, bottom); } /** * Resize the text size with default width and height */ public void resizeText() { int heightLimit = getHeight() - getPaddingBottom() - getPaddingTop(); int widthLimit = getWidth() - getPaddingLeft() - getPaddingRight(); resizeText(widthLimit, heightLimit); } /** * Resize the text size with specified width and height * @param width * @param height */ public void resizeText(int width, int height) { CharSequence text = getText(); // Do not resize if the view does not have dimensions or there is no text if (text == null || text.length() == 0 || height &lt;= 0 || width &lt;= 0 || mTextSize == 0) { return; } if (getTransformationMethod() != null) { text = getTransformationMethod().getTransformation(text, this); } // Get the text view's paint object TextPaint textPaint = getPaint(); // Store the current text size float oldTextSize = textPaint.getTextSize(); // If there is a max text size set, use the lesser of that and the default text size float targetTextSize = mMaxTextSize &gt; 0 ? Math.min(mTextSize, mMaxTextSize) : mTextSize; // Get the required text height int textHeight = getTextHeight(text, textPaint, width, targetTextSize); // Until we either fit within our text view or we had reached our min text size, incrementally try smaller sizes while (textHeight &gt; height &amp;&amp; targetTextSize &gt; mMinTextSize) { targetTextSize = Math.max(targetTextSize - 2, mMinTextSize); textHeight = getTextHeight(text, textPaint, width, targetTextSize); } // If we had reached our minimum text size and still don't fit, append an ellipsis if (mAddEllipsis &amp;&amp; targetTextSize == mMinTextSize &amp;&amp; textHeight &gt; height) { // Draw using a static layout // modified: use a copy of TextPaint for measuring TextPaint paint = new TextPaint(textPaint); // Draw using a static layout StaticLayout layout = new StaticLayout(text, paint, width, Alignment.ALIGN_NORMAL, mSpacingMult, mSpacingAdd, false); // Check that we have a least one line of rendered text if (layout.getLineCount() &gt; 0) { // Since the line at the specific vertical position would be cut off, // we must trim up to the previous line int lastLine = layout.getLineForVertical(height) - 1; // If the text would not even fit on a single line, clear it if (lastLine &lt; 0) { setText(""); } // Otherwise, trim to the previous line and add an ellipsis else { int start = layout.getLineStart(lastLine); int end = layout.getLineEnd(lastLine); float lineWidth = layout.getLineWidth(lastLine); float ellipseWidth = textPaint.measureText(mEllipsis); // Trim characters off until we have enough room to draw the ellipsis while (width &lt; lineWidth + ellipseWidth) { lineWidth = textPaint.measureText(text.subSequence(start, --end + 1).toString()); } setText(text.subSequence(0, end) + mEllipsis); } } } // Some devices try to auto adjust line spacing, so force default line spacing // and invalidate the layout as a side effect setTextSize(TypedValue.COMPLEX_UNIT_PX, targetTextSize); setLineSpacing(mSpacingAdd, mSpacingMult); // Notify the listener if registered if (mTextResizeListener != null) { mTextResizeListener.onTextResize(this, oldTextSize, targetTextSize); } // Reset force resize flag mNeedsResize = false; } // Set the text size of the text paint object and use a static layout to render text off screen before measuring private int getTextHeight(CharSequence source, TextPaint paint, int width, float textSize) { // modified: make a copy of the original TextPaint object for measuring // (apparently the object gets modified while measuring, see also the // docs for TextView.getPaint() (which states to access it read-only) TextPaint paintCopy = new TextPaint(paint); // Update the text paint object paintCopy.setTextSize(textSize); // Measure using a static layout StaticLayout layout = new StaticLayout(source, paintCopy, width, Alignment.ALIGN_NORMAL, mSpacingMult, mSpacingAdd, true); return layout.getHeight(); } } </code></pre> <p><strong>Warning.</strong> There is an important fixed bug affecting Android 3.1 - 4.04 causing all AutoResizingTextView widgets not to work. Please read: <a href="https://stackoverflow.com/a/21851157/2075875">https://stackoverflow.com/a/21851157/2075875</a></p>
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