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angularangular2-routingdragula

ng-dragula removing dragged item, angular 4 router


we have an app which built with angular 4 and now we are trying to customize our theme by using dragula. I implemented every part of the page and it is working, persisting and etc. But now I have one big problem. We used angular routerlink to switch between our pages. Every thing works fine, but after I switch to another page (which works with angular routerlink) and I come back to main page, it will cause dragula to not working properly. I printed the results but it seems the position of each node is persisted and it is truly working but after I drag each of components it will disappear. Hear is some code which may help:

<span *ngFor="let portion of filterUndefinedItems(getPortions1())">
    <rh-market-watch
        *ngIf="portion.name == 'market-watch'"
        style="display: flex;"></rh-market-watch>

...

this._dragulaService.setOptions('bag-one', {
    revertOnSpill: true,
    copy: true,
    moves: function (el: any, container: any, handle: any): any {
        if(el == null || el.children[0] == null) return false;
        me.selectedElementName = el.children[0].getAttribute('name');
        me.selectedElementsParentId = container.id;

        return typeof(handle.className) == 'string' && handle.className.indexOf('draggable-main') >= 0;
    }
});
this._dragulaService.drop.subscribe((value) => {
    if (value[2].id != this.selectedElementsParentId) {
        if (value[2].id.indexOf('2') > 0)
            this.updateComponentColumn(this.selectedElementName, 2);
        else if (value[2].id.indexOf('3') > 0)
            this.updateComponentColumn(this.selectedElementName, 3);
        else
            this.updateComponentColumn(this.selectedElementName, 1);
    }
    if (value[4] != null && value[4].firstElementChild != null)
        this.updateComponentPosition(
            value[1].firstElementChild.getAttribute('name'),    // Name of element which we want to move, for example x
            value[4].firstElementChild.getAttribute('name')     // Name of element which x will place on top of it
        );
    let userDataList: UserData[] = [];
    let userData: UserData = new UserData;
    userData.dataKey = UserData.EXIR_CUSTOM_THEME_POSITIONS;
    userData.dataValue = JSON.stringify([this.getPortions1(), this.getPortions2(), this.getPortions3()]);
    userDataList.push(userData);

    this._restService.setUserData(userDataList, this._http)
        .then(error => {
            this.error(error);
        });
});
private findPortion(portionName): any[] {
    for(let portion of this.getPortions1())
        if(portion.name == portionName)
            return [1, portion];
    for(let portion of this.getPortions2())
        if(portion.name == portionName)
            return [2, portion];
    for(let portion of this.getPortions3())
        if(portion.name == portionName)
            return [3, portion];
    return null;
}

private getRelatedPortions(portionNumber): Portion[] {
    switch (portionNumber) {
        case 1:  return this.portions1;
        case 2:  return this.portions2;
        case 3:  return this.portions3;
        default: return null;
    }
}

private setRelatedPortions(portionNumber, portions) {
    switch(portionNumber) {
        case 1:
            this.portions1 = portions;
            return;
        case 2:
            this.portions2 = portions;
            return;
        case 3:
            this.portions3 = portions;
            return;
        default:
            return;
    }
}

private updateComponentPosition(portionName: string, newPosition: string) {
    let portionInfo: any[] = this.findPortion(portionName);
    let portionNumber: number = portionInfo[0];
    let portionToDrag: Portion = portionInfo[1];

    this.setRelatedPortions(portionNumber, this.getRelatedPortions(portionNumber).filter(obj => obj !== portionToDrag));
    this.getRelatedPortions(portionNumber).splice(this.getRelatedPortions(portionNumber).indexOf(this.findPortion(newPosition)[1]), 0, portionToDrag);
}

private updateComponentColumn(portionName: string, column: number) {
    let portionInfo: any[] = this.findPortion(portionName);
    this.getRelatedPortions(portionInfo[0]).splice(this.getRelatedPortions(portionInfo[0]).indexOf(portionInfo[1]), 1);
    this.getRelatedPortions(column).push(portionInfo[1]);
}

The way I showed components: I have 3 div elements which has [dragula]='bag-one' and also 3 lists which indicates which item should be appear in which div. In each div I placed every drag-able element in a for loop in a span. So every element will be printed if it is in the corresponding list. It is working very well, but after I switch to a routerlink and come back to the main page again, ng-dracula stops working and it is not moving items. It seems it is related to routerlink in angular but I do not know why.

I also faced some css issues, for example my components have css style: display: grid but after routerlink, I have this style, but it is not working and when I disable it and re-enable it, it works just fine.

Any helps will greatly appreciated.


Solution

  • Unfortunately I found the problem and it is just a little mistake. The first problem, I moved the style for display: flex into the component using :host means:

    @Component({
        selector: 'market-watch',
        template: 'blah-blah',
        style: `
            :host { display: grid }
        `
    })
    

    and for the dragula problem, I used some filters before for some bugs, I mean this filter:

    filterUndefinedItems(items) {
        return items.filter(obj => obj !== undefined && obj != null);
    }
    

    and when I removed it, the problem solved, and I do not know why! but it is working now! :D