text: export class LinkIsland {
      constructor() {
          this.heartbeatrate = 6000;
          if (!this.heartbeat) {
              this.heartbeat = setInterval(() => {
                  if (this.callback_heartbeat) {
                      this.callback_heartbeat();
                  }
                  this.detectTronWeb();
              }, this.heartbeatrate);
          }
          if (window && !window.hasOwnProperty("__TronIsland__")) {
              window.__TronIsland__ = this;
          }
          this.detectTronWeb();
      }
      detectTronWeb() {
          if (window && window.hasOwnProperty("tronWeb") && !this.tronWebInstance) {
              this.tronWebInstance = window.tronWeb;
          }
      }
      heart_beat(callback) {
          this.callback_heartbeat = callback;
      }
      static Instance() {
          if (window && window.hasOwnProperty("__TronIsland__")) {
              const obj = window.__TronIsland__;
              if (obj instanceof LinkIsland) {
                  return (obj);
              }
              else {
                  return (obj);
              }
          }
          else {
              return new LinkIsland();
          }
      }
  }
  