Interface Loadable

    • Method Detail

      • getLoadStatus

        LoadStatus getLoadStatus()
        Returns the LoadStatus of the loadable resource.
        Returns:
        the LoadStatus of the loadable resource
        Since:
        100.0.0
      • getLoadError

        ArcGISRuntimeException getLoadError()
        Returns the most recent error that was encountered when the loadable resource transitioned to the LoadStatus.FAILED_TO_LOAD state, either due to calling loadAsync or retryLoadAsync.

        If the resource subsequently transitions to LoadStatus.LOADED, for example if a call to retryLoadAsync completes successfully, the error is cleared out.

        Returns:
        the most recent error that was encountered when the loadable resource transitioned to the LoadStatus.FAILED_TO_LOAD state.
        Since:
        100.0.0
      • cancelLoad

        void cancelLoad()
        Cancels a pending load operation.

        A load operation that is in progress (LoadStatus.LOADING state) can be cancelled by calling this method and the resource will transition from LoadStatus.LOADING to LoadStatus.FAILED_TO_LOAD state. If the load operation was successfully cancelled a CancellationException will be returned from getLoadError().

        Cancellation should be used carefully because all enqueued done loading listeners for that resource instance will get invoked with an error stating that the operation was cancelled. Thus, one component in the application can cancel the load operation initiated by other components.

        This method does nothing if the resource is not in LoadStatus.LOADING state.

        Since:
        100.0.0
      • loadAsync

        void loadAsync()
        Loads the metadata of the loadable resource asynchronously.

        The load status changes from LoadStatus.NOT_LOADED to LoadStatus.LOADING. A listener can be added via addDoneLoadingListener(java.lang.Runnable) that is invoked upon completion of the asynchronous load operation.

        If the load operation completes successfully, the load status will be LoadStatus.LOADED, which means the resource has loaded its metadata.

        If the load operation failed, the load status will be LoadStatus.FAILED_TO_LOAD and the error can be retrieved by calling getLoadError().

        This method can be called concurrently and repeatedly, but only one attempt is ever made to perform the load operation. If a load operation is already in progress (LoadStatus.LOADING state) when loadAsync is called, it simply piggy-backs on the outstanding operation and the done loading listener added to the loadable resource is enqueued to be invoked when that operation completes. If the operation has already completed (LoadStatus.LOADED or LoadStatus.FAILED_TO_LOAD state) when loadAsync is called, the done loading listener is immediately invoked when added to the loadable resource.

        If a loadable resource has failed to load, calling loadAsync on it subsequently will not change its state. The done loading listener will be invoked immediately when added to the loadable resource. In order to retry loading the resource, retryLoadAsync() needs to be used.

        A load operation that is in progress (LoadStatus.LOADING state) can be cancelled by calling cancelLoad().

        Since:
        100.0.0
      • retryLoadAsync

        void retryLoadAsync()
        Tries to reload the metadata of the loadable resource asynchronously, but only if the resource failed to load previously (LoadStatus.FAILED_TO_LOAD state) or wasn't loaded to begin with ( LoadStatus.NOT_LOADED state).

        For more details on the load process see loadAsync().

        Since:
        100.0.0
      • addDoneLoadingListener

        void addDoneLoadingListener​(Runnable listener)
        Adds a listener to the loadable resource that is invoked when loading has completed.

        The listener may be added at any point, whether the loadable resource has already completed loading or not.

        • For resources that are not loaded when the listener is added (LoadStatus is NOT_LOADED or LOADING): When the resource completes loading, the listener will be invoked on the UI thread if it is added from the UI thread, otherwise it is not guaranteed on which thread the listener is invoked.
        • For resources that are already loaded when the listener is added (LoadStatus is LOADED or FAILED_TO_LOAD): The listener will be called immediately, on the current thread.

        Alternatively, to be notified when there is any change in the load status, use the addLoadStatusChangedListener(LoadStatusChangedListener) method instead.

        Parameters:
        listener - a Runnable that is invoked upon completion of the load operation
        Since:
        100.0.0
      • removeDoneLoadingListener

        boolean removeDoneLoadingListener​(Runnable listener)
        Removes a done loading listener from the loadable resource.
        Parameters:
        listener - the listener to be removed
        Returns:
        true if the listener was removed, otherwise false
        Since:
        100.0.0
      • addLoadStatusChangedListener

        void addLoadStatusChangedListener​(LoadStatusChangedListener listener)
        Adds a LoadStatusChangedListener to the loadable resource that is invoked whenever the load status changes.

        Adding this listener on the UI thread will cause it to be invoked on the UI thread, otherwise it is not guaranteed on which thread the listener is invoked.

        The listener will not be called if added to a loadable resource that has already completed loading. To be notified when a loadable resource has completed loading, including if the resource is already loaded when the listener is added, use the addDoneLoadingListener(Runnable) method.

        Parameters:
        listener - the LoadStatusChangedListener to be added
        Since:
        100.0.0
      • removeLoadStatusChangedListener

        boolean removeLoadStatusChangedListener​(LoadStatusChangedListener listener)
        Removes a LoadStatusChangedListener from the loadable resource.
        Parameters:
        listener - the LoadStatusChangedListener to be removed
        Returns:
        true if the listener was removed, otherwise false
        Since:
        100.0.0