[[["易于理解","easyToUnderstand","thumb-up"],["解决了我的问题","solvedMyProblem","thumb-up"],["其他","otherUp","thumb-up"]],[["很难理解","hardToUnderstand","thumb-down"],["信息或示例代码不正确","incorrectInformationOrSampleCode","thumb-down"],["没有我需要的信息/示例","missingTheInformationSamplesINeed","thumb-down"],["翻译问题","translationIssue","thumb-down"],["其他","otherDown","thumb-down"]],["最后更新时间 (UTC):2025-08-25。"],[],[],null,["# Creating an item chart with the Chart Config Editor\n\n| **Note:** Starting in Looker 24.20, the Chart Config Editor supports the creation of item charts.\n\nAn item chart displays categorical and hierarchical data as a set of dots. Each dot represents a data value or group of data values.\n\nUsing the [Chart Config Editor](/looker/docs/chart-config-editor), you can create item charts by starting from a [column chart](/looker/docs/column-options) in Looker.\n\nItem charts require at least one dimension and exactly one measure.\n\nFor example, you can create an item chart that shows the **Inventory Item Count** measure value over several different **Seasonal Collection** dimension values. The dots will be colored according to the dimension values.\n\nPrerequisites\n-------------\n\nTo access the Chart Config Editor, you must have the [`can_override_vis_config` permission](/looker/docs/admin-panel-users-roles#can_override_vis_config).\n\nWriting the JSON snippet\n------------------------\n\nTo create an item chart, start from the following JSON snippet: \n\n {\n chart: {\n type: 'item',\n }\n }\n\nCreating an item chart\n----------------------\n\nTo create an item chart, follow these steps:\n\n1. View a [column chart](/looker/docs/column-options) in an Explore, or edit a column chart in a Look or dashboard.\n\n Item charts require at least one dimension and exactly one measure. Your starting chart might look something like this example:\n\n2. Open the **Edit** menu in the visualization.\n\n3. In the **Plot** tab, click the **Edit Chart Config** button. Looker displays the **Edit Chart Config** dialog.\n\n4. Select the **Chart Config (Override)** section, and enter the HighCharts JSON from the [Writing the JSON snippet](#json) section of this page.\n\n5. To let Looker properly format your JSON, click **\\\u003c\\\u003e (Format code)**.\n\n6. To test your changes, click **Preview**.\n\n7. To apply your changes, click **Apply**. The visualization will be displayed using the custom JSON values.\n\nOnce you've customized your visualization, you can save it.\n\n### Changing the layout style\n\nBy default, the item chart displays items in a semicircle. You can change the shape of the chart by using the `startAngle` and `endAngle` properties.\n\nFor example, to create a circular item chart, use the following JSON: \n\n {\n chart: {\n type: 'item'\n },\n series: [{\n startAngle: null,\n endAngle: null\n }]\n }\n\nTo create a rectangular item chart, use the following JSON: \n\n {\n chart: {\n type: 'item'\n },\n series: [{\n startAngle: null,\n endAngle: null\n }]\n }\n\nLimitations and requirements\n----------------------------\n\nWhen you're using item charts, keep the following limitations and requirements in mind:\n\n- Item charts require exactly one measure.\n- Item charts require at least one dimension.\n- Item charts don't support pivoted dimensions.\n- If your measure values are larger than the number of dots that Looker can display, Looker adds a label below the chart that denotes how many values each dot represents.\n- Item charts can only render queries with 50 rows or fewer."]]