如何在角度2中响应挂起时显示加载器？

Question

下面我使用了这个loadImage函数来加载图像，我希望在响应处理时显示加载图像。这是._url_img我的最终响应。

 loadImage()
    {
   this.isShowDocumentGif=false;
   return   this._organizations.getLogoUrldocumentmedia(this.documentlist).single().toPromise()
            .then(url => {
           this.isShowDocumentGif=false;

                this._user_img = url;
            })
            .catch(e => {
                this.isShowDocumentGif=false;
                console.log('Logo error', e);
                throw e;
            });
    }

Answer 1

像这样使用

anyFunction(){
  this.isShowDocumentGif = true //variable to toggle your loader

  return this._organizations.getLogoUrldocumentmedia(this.documentlist).single().toPromise()
   .then(url => {
       this.isShowDocumentGif=false;
       this._user_img = url;
   })
   .catch(e => {
       this.isShowDocumentGif=false;
       console.log('Logo error', e);
       throw e;
   });
}