How do I tell if my textview has been ellipsized?
I have a multi-line TextView
that has android:ellipsize="end"
set. I would like to know, however, if the string I place in there is actually too long (so that I may make sure the full string is shown elsewhere on the page).
I could use TextView.length()
and find about what the approximate length of string will fit, but since it's multiple lines, the TextView
handles when to wrap, so this won't always work.
Any idea开发者_开发技巧s?
You can get the layout of the TextView
and check the ellipsis count per line. For an end ellipsis, it is sufficient to check the last line, like this:
Layout l = textview.getLayout();
if (l != null) {
int lines = l.getLineCount();
if (lines > 0)
if (l.getEllipsisCount(lines-1) > 0)
Log.d(TAG, "Text is ellipsized");
}
This only works after the layout phase, otherwise the returned layout will be null, so call this at an appropriate place in your code.
textView.getLayout is the way to go but the problem with that is that it returns null if layout is not prepared. Use the below solution.
ViewTreeObserver vto = textview.getViewTreeObserver();
vto.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
Layout l = textview.getLayout();
if ( l != null){
int lines = l.getLineCount();
if ( lines > 0)
if ( l.getEllipsisCount(lines-1) > 0)
Log.d(TAG, "Text is ellipsized");
}
}
});
Code snippet for removing the listener (source):
mLayout.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
public void onGlobalLayout() {
scrollToGridPos(getCenterPoint(), false);
mLayout.getViewTreeObserver().removeOnGlobalLayoutListener(this);
}
});
I think the easiest solution to this question is the following code:
String text = "some looooong text";
textView.setText(text);
boolean isEllipsize = !((textView.getLayout().getText().toString()).equalsIgnoreCase(text));
This code assumes that in your XML the TextView set a maxLineCount
:)
This worked to me:
textView.post(new Runnable() {
@Override
public void run() {
if (textView.getLineCount() > 1) {
//do something
}
}
});
The most eloquent solution I have found (in Kotlin) is to create an extension function on TextView
fun TextView.isEllipsized() = layout.text.toString() != text.toString()
This is great because it doesn't require knowing what the full string is or worrying about how many lines the TextView
is using.
TextView.text
is the full text that it's trying to show, whereas TextView.layout.text
is what's actually shown on the screen so if they are different it must be getting ellipsized
To use it:
if (my_text_view.isEllipsized()) {
...
}
public int getEllipsisCount (int line):
Returns the number of characters to be ellipsized away, or 0 if no ellipsis is to take place.
So, simply call :
int lineCount = textview1.getLineCount();
if(textview1.getLayout().getEllipsisCount(lineCount) > 0) {
// Do anything here..
}
Since the getLayout() cant be called before the layout is set, use this:
ViewTreeObserver vto = textview.getViewTreeObserver();
vto.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
Layout l = textview.getLayout();
if ( l != null){
int lines = l.getLineCount();
if ( lines > 0)
if ( l.getEllipsisCount(lines-1) > 0)
Log.d(TAG, "Text is ellipsized");
}
}
});
And finally do not forget to remove removeOnGlobalLayoutListener when you need it nomore.
lateinit var toggleMoreButton: Runnable
toggleMoreButton = Runnable {
if(reviewTextView.layout == null) { // wait while layout become available
reviewTextView.post(toggleMoreButton)
return@Runnable
}
readMoreButton.visibility = if(reviewTextView.layout.text.toString() != comment) View.VISIBLE else View.GONE
}
reviewTextView.post(toggleMoreButton)
It is some typical case:
- comment in 'reviewTextView'
- comment can collapsed by some criteria
- if comment collapsed you show button 'readMoreButton'
The Kotlin way:
textView.post {
if (textView.lineCount > MAX_LINES_COLLAPSED) {
// text is not fully displayed
}
}
Actually View.post()
is executed after the view has been rendered and will run the function provided
Simple Kotlin method. Allows android:ellipsize
and android:maxLines
to be used
fun isEllipsized(textView: TextView, text: String?) = textView.layout.text.toString() != text
Solution with kotlin extensions:
infoText.afterLayoutConfiguration {
val hasEllipsize = infoText.hasEllipsize()
...
}
Extensions:
/**
* Function for detect when layout completely configure.
*/
fun View.afterLayoutConfiguration(func: () -> Unit) {
viewTreeObserver?.addOnGlobalLayoutListener(object : ViewTreeObserver.OnGlobalLayoutListener {
override fun onGlobalLayout() {
viewTreeObserver?.removeOnGlobalLayoutListener(this)
func()
}
})
}
fun TextView.hasEllipsize(): Boolean = layout.getEllipsisCount(lineCount - 1) > 0
it is working for me
if (l != null) {
int lines = l.getLineCount();
if (lines > 0) {
for (int i = 0; i < lines; i++) {
if (l.getEllipsisCount(i) > 0) {
ellipsize = true;
break;
}
}
}
}
If your textview contains multiple paragraphs, using getEllipsisCount will not work for empty lines within it. getEllipsisCount for the last line of any paragraph will return 0.
Really work so, for example, to pass full data to dialog from item of RecyclerView:
holder.subInfo.post(new Runnable() {
@Override
public void run() {
Layout l = holder.subInfo.getLayout();
if (l != null) {
final int count = l.getLineCount();
if (count >= 3) {
holder.subInfo.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
final int c = holder.subInfo.getLineCount();
if (c >= 3) {
onClickToShowInfoDialog.showDialog(holder.title.getText().toString(), holder.subInfo.getText().toString());
}
}
});
}
}
}
});
Combining @Thorstenvv awnser with @Tiano fix, here is the Kotlin version :
val layout = textView.layout ?: return@doOnLayout
val lines = layout.lineCount
val hasLine = lines > 0
val hasEllipsis = ((lines - 1) downTo 0).any { layout.getEllipsisCount(it) > 0 }
if (hasLine && hasEllipsis) {
// Text is ellipsized
}
In Kotlin, you can use the below code.
var str= "Kotlin is one of the best languages."
textView.text=str
textView.post {
val isEllipsize: Boolean = !textView.layout.text.toString().equals(str)
if (isEllipsize) {
holder.itemView.tv_viewMore.visibility = View.VISIBLE
} else {
holder.itemView.tv_viewMore.visibility = View.GONE
}
}
This is simple library for creating textview expandable. Like Continue or Less. This library extended version TextView. Easy to use.
implementation 'com.github.mahimrocky:ShowMoreText:1.0.2'
Like this, 1 https://raw.githubusercontent.com/mahimrocky/ShowMoreText/master/screenshot1.png
2 https://raw.githubusercontent.com/mahimrocky/ShowMoreText/master/screenshot2.png
<com.skyhope.showmoretextview.ShowMoreTextView
android:id="@+id/text_view_show_more"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/text"
/>
In Activity you can use like:
ShowMoreTextView textView = findViewById(R.id.text_view_show_more);
//You have to use following one of method
// For using character length
textView.setShowingChar(numberOfCharacter);
//number of line you want to short
textView.setShowingLine(numberOfLine);
Using getEllipsisCount
won't work with text that has empty lines within it. I used the following code to make it work :
message.getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
@Override
public boolean onPreDraw() {
if(m.isEllipsized == -1) {
Layout l = message.getLayout();
if (message.getLineCount() > 5) {
m.isEllipsized = 1;
message.setMaxLines(5);
return false;
} else {
m.isEllipsized = 0;
}
}
return true;
}
});
Make sure not to set a maxLineCount
in your XML. Then you can check for the lineCount
in your code and if it is greater than a certain number, you can return false to cancel the drawing of the TextView
and set the line count as well as a flag to save whether the text view is too long or not. The text view will draw again with the correct line count and you will know whether its ellipsized or not with the flag.
You can then use the isEllipsized
flag to do whatever you require.
create a method inside your TextViewUtils class
public static boolean isEllipsized(String newValue, String oldValue) {
return !((newValue).equals(oldValue));
}
call this method when it's required eg:
if (TextViewUtils.isEllipsized(textviewDescription.getLayout().getText().toString(), yourModelObject.getDescription()))
holder.viewMore.setVisibility(View.VISIBLE);//show view more option
else
holder.viewMore.setVisibility(View.GONE);//hide
but textView.getLayout() can't call before the view(layout) set.
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