The metadata tag represents custom metadata of a HAP. The tag value is an array and contains three subtags: name, value, and resource.
Table 1 metadata tag description
| Subtag | Description | Data Type | Optional |
|---|---|---|---|
| name | Name of the data item. The value is a string with a maximum of 255 bytes. | String | Optional, defaults to an empty string |
| value | Value of the data item. The value is a string with a maximum of 255 bytes. | String | Optional, defaults to an empty string |
| resource | Custom data, which is a resource index. The value is a string with a maximum of 255 bytes. For example, $profile:shortcuts_config indicates that the data points to the /resources/base/profile/shortcuts_config.json file. | String | Optional, defaults to an empty string |
Below are several use cases and examples for the metadata tag. You can customize the settings based on service requirements.
Use the metadata tag to configure the default size and position (in vp) of the main window. The following name options are available:
Use the metadata tag to configure the enabled status of the removeStartingWindow API. Set name to enable.remove.starting.window, and set value to true to enable the API, or to false to disable it. The default value is false.
Use the metadata tag to configure whether the main window is maximized upon startup. Set name to ohos.ability.window.isMaximize, and set value to true to maximize the main window upon startup, or to false to start in a non-maximized state. The default value is false. This configuration has the following restrictions:
Use the metadata tag to configure the supported window modes in freeform window mode. The configuration item is as follows: set name to ohos.ability.window.supportWindowModeInFreeMultiWindow, and set value to fullscreen (fullscreen mode), split (split screen mode), or floating (floating window mode). The value is a string and can contain multiple modes separated by commas (,), without spaces and in any order, for example, fullscreen,split. This configuration takes effect only on devices that support and are in freeform window mode. On devices that support but are not in freeform window mode, or on devices that do not support freeform window mode, the configuration neither takes effect nor reports an error.
In free multi-window mode, the supported window modes can be configured using multiple methods. The configuration priorities are as follows: using SetSupportedWindowModes to configure the window modes > using StartAbility to configure the SupportWindowMode property in StartOptions > using the metadata tag to configure the window modes > configuring the SupportWindowMode property in the abilities tag of the module.json5 file.
In non-free-windows mode, the supported window modes can only be configured through the SupportWindowMode property under the abilities tag in the module.json5 file. Other configuration methods do not take effect.
{
"module": {
"abilities": [{
"metadata": [{
"name": "ability_metadata",
"value": "a test demo for ability",
"resource": "$profile:config_file"
},
{
"name": "ability_metadata_2",
"value": "a string test",
"resource": "$profile:config_file"
},
{
"name": "ohos.ability.window.height",
"value": "987"
},
{
"name": "ohos.ability.window.width",
"value": "1300"
},
{
"name": "ohos.ability.window.left",
"value": "right-50"
},
{
"name": "ohos.ability.window.top",
"value": "center+50"
},
{
"name": "ohos.ability.window.isMaximize",
"value": "true"
},
{
"name": "enable.remove.starting.window",
"value": "true"
},
{
"name": "ohos.ability.window.supportWindowModeInFreeMultiWindow",
"value": "fullscreen,split,floating",
}],
}],
"extensionAbilities": [{
"metadata": [{
"name": "extensionAbility_metadata",
"value": "a test for extensionAbility",
"resource": "$profile:config_file"
},
{
"name": "extensionAbility_metadata_2",
"value": "a string test",
"resource": "$profile:config_file"
}],
}]
}
}