我可以限制 TextView 的字符数吗？

you can extend the TextView class and overwrite the setText() function. In this function you check for text length or word cound.

Here is an example. I limit the sizewith the maxLength attribute, limit it to a single line with maxLines attribute, then use the ellipsize=end to add a "..." automatically to the end of any line that has been cut-off.

<TextView
android:id="@+id/secondLineTextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:maxLines="1"
android:maxLength="10"
android:ellipsize="end"/>

You can use setEllipsize method of TextView class http://developer.android.com/reference/android/widget/TextView.html#setEllipsize(android.text.TextUtils.TruncateAt)

With the constants of TextUtil class for added the suspension points http://developer.android.com/reference/android/text/TextUtils.TruncateAt.html

Use below code in TextView

 android:maxLength="65"

Enjoy...

If your not interested in xml solutions maybe you can do this:

String s="Hello world";
Textview someTextView;
someTextView.setText(getSafeSubstring(s, 5));
//the text of someTextView will be Hello

...

public String getSafeSubstring(String s, int maxLength){
if(!TextUtils.isEmpty(s)){
if(s.length() >= maxLength){
return s.substring(0, maxLength);
}
}
return s;
}

As mentioned in https://stackoverflow.com/a/6165470/1818089 & https://stackoverflow.com/a/6239007/1818089, using

android:minEms="2"

should be enough to achieve the goal stated above.

I did this using the maxEms attribute.

 <TextView
android:ellipsize="end"
android:maxEms="10"/>

Programmatic Kotlin.

Cut off the start of the text:

 val maxChars = 10000
if (helloWorldTextView.text.length > maxChars) {
helloWorldTextView.text = helloWorldTextView.text.takeLast(maxChars)
}

Cut off the end of the text:

 val maxChars = 10000
if (helloWorldTextView.text.length > maxChars) {
helloWorldTextView.text = helloWorldTextView.text.take(maxChars)
}

I am sharing an example where I have set maxLength=1 i.e. limit it to a single line with maxLines attribute, then use the ellipsize=end to add a "..." automatically to the end of any line that has been cut-off.

Please Note: layout_width which is 120dp i.e. after 120dp any text exceeding will triggrer "ellipsize=end" property

paste the below code directly to check.

<TextView
android:layout_width="120dp"
android:layout_height="wrap_content"
android:ellipsize="end"
android:maxLines="1"
android:maxLength="40"
android:text="Can I limit TextView's number of characters?"
android:textColor="@color/black"
android:textSize="12sp"
android:textStyle="bold" />

.