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@lsurvila
Last active September 16, 2015 11:48
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Fixes ellipsizing behaviour on certain cases when text has \n in it.
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;
/**
* Fixes ellipsizing behaviour on certain cases when text has \n in it.
* When view is drawn first will display ellipses with default Android ellipsize method after
* expanding/hiding will use this method. FIXME refactor to always use this method.
* Taken from http://stackoverflow.com/questions/2160619/android-ellipsize-multiline-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;
} else {
// if it's not drawn yet will use default ellipsize method.
super.setEllipsize(TextUtils.TruncateAt.END);
}
}
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
}
}
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