Measuring the length of multiline text is simple in B4A with StringUtils.MeasureMultilineTextHeight and in B4i by setting the width of a multiline Label and calling SizeToFit.
There is no similar method available in B4J. One option is to add a label to an AnchorPane and wait for the layout to be set: https://www.b4x.com/android/forum/threads/measure-text.45750/#post-311358
Another option is to call a non-public API with the following code:
Usage example:
Note that if you want to add it to a class then you need to remove the 'static' modifier from the Java code.
As this is a non-public API it might change in the future. It does work with Java 8 and Java 9 so it is probably quite safe to use.
There is no similar method available in B4J. One option is to add a label to an AnchorPane and wait for the layout to be set: https://www.b4x.com/android/forum/threads/measure-text.45750/#post-311358
Another option is to call a non-public API with the following code:
B4X:
Sub MeasureMultilineTextHeight (Font As Font, Width As Double, Text As String) As Double
Dim jo As JavaObject = Me
Return jo.RunMethod("MeasureMultilineTextHeight", Array(Font, Text, Width))
End Sub
#if Java
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import javafx.scene.text.Font;
import javafx.scene.text.TextBoundsType;
public static double MeasureMultilineTextHeight(Font f, String text, double width) throws Exception {
Method m = Class.forName("com.sun.javafx.scene.control.skin.Utils").getDeclaredMethod("computeTextHeight",
Font.class, String.class, double.class, TextBoundsType.class);
m.setAccessible(true);
return (Double)m.invoke(null, f, text, width, TextBoundsType.LOGICAL_VERTICAL_CENTER);
}
#End IfUsage example:
B4X:
Dim height As Double = MeasureMultilineTextHeight(fx.DefaultFont(20), 100, $" jskldf jslkd fjlk wel;fk we;lfk we;lf k
erg
erg
erg
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gsdfj lksdf jlksd fjlksd f"$)
Log(height)Note that if you want to add it to a class then you need to remove the 'static' modifier from the Java code.
As this is a non-public API it might change in the future. It does work with Java 8 and Java 9 so it is probably quite safe to use.
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