What methods does the viewer call?

The methods called by viewer are: 1. Initialize Viewer; 2. Load data; 3. Set chart parameters; 4. Display and update charts; 5. Respond to user interaction; 6. Save and export charts; 7. Close Viewer. Detailed introduction: 1. Initialize Viewer, which is the first step to use Viewer. Usually you need to call an initialization method to create a Viewer instance and set relevant parameters; 2. Load data. Once Viewer initialization is completed, you can use the method of loading data. To obtain the data to be displayed, etc.

Viewer has many different calling methods, depending on the functionality and requirements to be implemented. The following are some common Viewer calling methods:

1. Initialize Viewer: This is the first step in using Viewer. It is usually necessary to call an initialization method to create a Viewer instance and set related parameters. . This process may include specifying the data source to use, setting up the initial view, selecting the type of chart to use, etc.

2. Loading data: Once the Viewer is initialized, you can use the loading data method to obtain the data to be displayed. This usually involves getting data from a database, file, or other data source and passing it to the Viewer. Methods of loading data may include executing SQL queries, reading file contents, etc.

3. Set chart parameters: Viewer usually supports multiple chart types (such as bar charts, line charts, pie charts, etc.), and each chart type has some configurable parameters. By calling the corresponding methods, you can set the chart's title, axis, color scheme, etc. These methods usually provide options and parameters that allow the user to customize the appearance and behavior of the chart.

4. Display and update charts: After loading data and setting parameters, you can use the method of displaying or updating charts to present the data to the user. This process may involve rendering the chart, updating chart elements, refreshing the display, etc. Methods for displaying and updating charts are called periodically to update data in real time or in response to user interaction.

5. Respond to user interaction: In order to improve user experience, Viewer usually supports interaction with users, such as zooming, panning, selection, etc. These interaction events can be monitored and processed by calling the corresponding methods. For example, when the user clicks on an element in the chart, a method can be called to obtain the data of the element and display relevant information in the Viewer.

6. Saving and exporting charts: In order to facilitate users to share or save charts, Viewer usually provides methods to save and export charts. These methods can export charts as images, PDFs, or other format files and allow the user to select export options and parameters.

7. Close Viewer: When Viewer is no longer needed, the shutdown method should be called to release resources and clean up memory. This process may include operations such as closing database connections and releasing window handles.

In addition to the methods listed above, the specific calling method also depends on the programming language and library used. Different programming languages ​​and libraries may have different APIs and syntax rules, so you should refer to the corresponding documentation and sample code when using Viewer.

In addition, in order to ensure the normal operation and optimal performance of Viewer, there are some best practices and precautions that you should pay attention to. For example, frequent loading of large amounts of data should be avoided to avoid performance bottlenecks; charts should be updated in a timely manner to reflect the latest data; memory and CPU resources should be used rationally to avoid unnecessary waste of resources; user interaction events should be processed in a timely manner to provide smooth user experience, etc.

In short, the calling method of Viewer depends on the specific needs and usage scenarios. By using these methods appropriately, you can effectively display data, improve user experience, and enhance application functionality.

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