Directive for NativeScript-angular, adding the property maxLines to Label

label-max-lines.directive.ts

// Usage: <Label maxLines="3" .. />

import { Directive, ElementRef, Input, OnInit, OnChanges } from '@angular/core';
import { Label } from 'tns-core-modules/ui/label';

declare const android, NSLineBreakMode: any;

@Directive({
  selector: 'Label[maxLines]',
})
export class LabelMaxLinesDirective implements OnInit, OnChanges {
  @Input('maxLines') public maxLines: number = 1;

  public get nativeView(): Label {
    return this.el.nativeElement;
  }

  constructor(private el: ElementRef) {}

  public ngOnInit() {
    const nativeView = this.nativeView;

    if (nativeView instanceof Label) {
      nativeView.on(Label.loadedEvent, () => {
        this.applyMaxLines();
      });
    }
  }

  public ngOnChanges(changes: any) {
    if (changes.maxLines) {
      this.applyMaxLines();
    }
  }

  private applyMaxLines() {
    const nativeView = this.nativeView;

    const maxLines = Math.max(Number(this.maxLines) || 0, 1);

    if (nativeView.android) {
      nativeView.android.setMaxLines(maxLines);
      nativeView.android.setEllipsize(android.text.TextUtils.TruncateAt.END);
    } else if (nativeView.ios) {
      setTimeout(() => {
        nativeView.ios.numberOfLines = maxLines;
        nativeView.ios.adjustsFontSizeToFitWidth = false;
        nativeView.ios.lineBreakMode = NSLineBreakMode.ByTruncatingTail;
      }, 0);
    }
  }
}

Thanks @EddyVerbruggen, you're awesome!

@EddyVerbruggen Shouldn't nativeView.on need .off also ? Where is the right place to put it ?

@RoyiNamir I'm not sure that's required in this case, but one could add it to the applyMaxLines function.

Hi @EddyVerbruggen, i am currently using this code. But i have to add nativeView.android.setSingleLine(false); before nativeView.android.setMaxLines(maxLines); otherwise it isn`t working

HI @EddyVerbruggen,
Can you please explain how this directive can be used in a nativescript app?
I have saved this in my project and tried to use it but I cannot see any changes on the lables.

👍

Hi guys, did anyone rewrite this for pure js (not ng or typescript)? This is great but does not work for me :/
Same thing for @rudii1410

❤️
@EddyVerbruggen It works almost perfect...
But the Label node has the same height as before the truncating
Unfortunately NS does not have max-height :(
Any suggestion for this problem?

@anki247 i have the same issue, have you solved?

Hi @EddyVerbruggen, i am currently using this code. But i have to add nativeView.android.setSingleLine(false); before nativeView.android.setMaxLines(maxLines); otherwise it isn`t working

Me too

❤️
@EddyVerbruggen It works almost perfect...
But the Label node has the same height as before the truncating
Unfortunately NS does not have max-height :(
Any suggestion for this problem?

using the sizeToFit() to adjust height of label
refer: https://developer.apple.com/documentation/uikit/uilabel/1620539-numberoflines

❤️
@EddyVerbruggen It works almost perfect...
But the Label node has the same height as before the truncating
Unfortunately NS does not have max-height :(
Any suggestion for this problem?

using the sizeToFit() to adjust height of label
refer: https://developer.apple.com/documentation/uikit/uilabel/1620539-numberoflines

Man you're awsome, thank you so much for this suggestion.

@huuthangdut or @mrcretu can show a code example for the sizeToFit() function please'
I tried but the label didn't change.
Thanks!
Marco

This works fine for me. Using NativeScript v8 and Angular v16. Thanks @EddyVerbruggen