我用这个类来解决这个问题
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);
TypedArray a = context.obtainStyledAttributes(attrs, new int[] { android.R.attr.maxLines });
setMaxLines(a.getInt(0, 1));
}
public EllipsizingTextView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
TypedArray a = context.obtainStyledAttributes(attrs, new int[] { android.R.attr.maxLines });
setMaxLines(a.getInt(0, 1));
}
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) {
workingText = workingText.substring(0,
workingText.length() - 1 - 1);
}
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
}
}