AssetPickerBuilderDelegate<Asset, Path> class abstract

The delegate to build the whole picker's components.

By extending the delegate, you can customize every components on you own. Delegate requires two generic types:

• Asset The type of your assets. Defaults to AssetEntity.
• Path The type of your paths. Defaults to AssetPathEntity.

Constructors

AssetPickerBuilderDelegate({required PermissionState initialPermission, int gridCount = 4, ThemeData? pickerTheme, SpecialItemPosition specialItemPosition = SpecialItemPosition.none, SpecialItemBuilder<Path>? specialItemBuilder, LoadingIndicatorBuilder? loadingIndicatorBuilder, AssetSelectPredicate<Asset>? selectPredicate, bool? shouldRevertGrid, LimitedPermissionOverlayPredicate? limitedPermissionOverlayPredicate, PathNameBuilder<AssetPathEntity>? pathNameBuilder, AssetsChangeCallback<AssetPathEntity>? assetsChangeCallback, AssetsChangeRefreshPredicate<AssetPathEntity>? assetsChangeRefreshPredicate, Color? themeColor, AssetPickerTextDelegate? textDelegate, Locale? locale})

Properties

appBarItemHeight → double

Item's height in app bar. 顶栏内各个组件的统一高度

no setter

appBarPreferredSize ↔ Size?

The preferred size of appBar. appBar 的首选大小。

getter/setter pair

appleOSBlurRadius → double

Blur radius in Apple OS layout mode. 苹果系列系统布局方式下的模糊度

no setter

assetsChangeCallback → AssetsChangeCallback<AssetPathEntity>?

The callback that will be called when the system notifies assets changes. 当系统通知资源变化时将调用的回调。

final

assetsChangeRefreshPredicate → AssetsChangeRefreshPredicate<AssetPathEntity>?

Whether assets changing should call refresh with the given call and the current selected path. 判断资源变化是否根据 call 和当前选中的 path 进行更新。

final

bottomActionBarHeight → double

Height for bottom action bar. 底部操作栏的高度

no setter

bottomSectionHeight → double

Height for the bottom occupied section. 底部区域占用的高度

no setter

gridCount → int

Assets count for the picker. 资源网格数

final

gridRevertKey → GlobalKey<State<StatefulWidget>>

The GlobalKey for assetsGridBuilder to locate the ScrollView.center. assetsGridBuilder 用于定位 ScrollView.center 的 GlobalKey

final

gridScrollController → ScrollController

The ScrollController for the preview grid.

final

hashCode → int

The hash code for this object.

no setter, inherited

initialPermission → PermissionState

The PermissionState when the picker is called. 当选择器被拉起时的权限状态

final

isPermissionLimited → bool

Whether the permission is limited currently. 当前的权限是否为受限

no setter

isSingleAssetMode → bool

Whether the picker is under the single asset mode. 选择器是否为单选模式

no setter

isSwitchingPath → ValueNotifier<bool>

If path switcher opened. 是否正在进行路径选择

final

itemSpacing → double

Space between assets item widget. 资源部件之间的间隔

no setter

limitedPermissionOverlayPredicate → LimitedPermissionOverlayPredicate?

Predicate whether the limited permission overlay should be displayed. 判断有限的权限情况下是否展示提示页面。

final

loadingIndicatorBuilder → LoadingIndicatorBuilder?

Indicates the loading status for the builder. 指示目前加载的状态

final

onAssetsChangedLock ↔ Completer<void>?

Throttle the assets changing calls.

getter/setter pair

overlayStyle → SystemUiOverlayStyle

Return a system ui overlay style according to the brightness of the theme data. 根据主题返回状态栏的明暗样式

no setter

pathNameBuilder → PathNameBuilder<AssetPathEntity>?

Build customized path name. 构建自定义路径名称。

final

permission → ValueNotifier<PermissionState>

no setter

permissionLimitedBarHeight → double

Height for the permission limited bar. 权限受限栏的高度

no setter

permissionNotifier → ValueNotifier<PermissionState>

Notifier for the current PermissionState. 当前 PermissionState 的监听

late, final

permissionOverlayDisplay → ValueNotifier<bool>

late, final

pickerTheme → ThemeData?

Theme for the picker. 选择器的主题

final

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

selectPredicate → AssetSelectPredicate<Asset>?

Predicate whether an asset can be selected or unselected. 判断资源可否被选择。

final

semanticsTextDelegate → AssetPickerTextDelegate

no setter

shouldBuildSpecialItem → bool

Whether the delegate should build the special item. 是否需要构建自定义 item

no setter

shouldRevertGrid → bool?

Whether the assets grid should revert. 判断资源网格是否需要倒序排列

final

specialItemBuilder → SpecialItemBuilder<Path>?

The widget builder for the the special item. 自定义 item 的构造方法

final

specialItemPosition → SpecialItemPosition

Allow users set a special item in the picker with several positions. 允许用户在选择器中添加一个自定义 item，并指定位置

final

textDelegate → AssetPickerTextDelegate

no setter

theme → ThemeData

ThemeData for the picker. 选择器使用的主题

no setter

themeColor → Color?

Main color for the picker. 选择器的主题色

final

Methods

accessLimitedBottomTip(BuildContext context) → Widget

The tip widget displays when the access is limited. 当访问受限时在底部展示的提示

androidLayout(BuildContext context) → Widget

Layout for Android devices. Android设备的选择器布局

appBar(BuildContext context) → PreferredSizeWidget

Custom app bar for the picker. 选择器自定义的顶栏

appleOSLayout(BuildContext context) → Widget

Layout for Apple OS devices. 苹果系列设备的选择器布局

assetGridItemBuilder(BuildContext context, int index, List<Asset> currentAssets) → Widget

The item builder for the assets' grid. 资源列表项的构建

assetGridItemSemanticsBuilder(BuildContext context, int index, Asset asset, Widget child) → Widget

The Semantics builder for the assets' grid. 资源列表项的语义构建

assetsGridBuilder(BuildContext context) → Widget

The main grid view builder for assets. 主要的资源查看网格部件

assetsGridItemCount({required BuildContext context, required List<Asset> assets, int placeholderCount = 0}) → int

The function which return items count for the assets' grid. 为资源列表提供内容数量计算的方法

audioIndicator(BuildContext context, Asset asset) → Widget

Audio asset type indicator. 音频类型资源指示

audioItemBuilder(BuildContext context, int index, Asset asset) → Widget

The item builder for audio type of asset. 音频资源的部件构建

backButton(BuildContext context) → Widget

Back button. 返回按钮

bottomActionBar(BuildContext context) → Widget

Action bar widget aligned to bottom. 底部操作栏部件

build(BuildContext context) → Widget

Yes, the build method. 没错，是它是它就是它，我们亲爱的 build 方法~

buildLivePhotoIndicator(BuildContext context, Asset asset) → Widget

confirmButton(BuildContext context) → Widget

Confirm button. 确认按钮

dispose() → void

Keep a dispose method to sync with State. 保留一个 dispose 方法与 State 同步。

effectiveGridDirection(BuildContext context) → TextDirection

The effective direction for the assets grid. 网格实际的方向

effectiveShouldRevertGrid(BuildContext context) → bool

emptyIndicator(BuildContext context) → Widget

Indicator when no assets were found from the current path. 当前目录下无资源的显示

failedItemBuilder(BuildContext context) → Widget

Item widgets when the thumb data load failed. 资源缩略数据加载失败时使用的部件

findChildIndexBuilder({required String id, required List<Asset> assets, int placeholderCount = 0}) → int?

Indicates how would the grid found a reusable RenderObject through id. 为 Grid 布局指示如何找到可复用的 RenderObject。

gifIndicator(BuildContext context, Asset asset) → Widget

GIF image type indicator. GIF 类型图片指示

imageAndVideoItemBuilder(BuildContext context, int index, Asset asset) → Widget

The item builder for images and video type of asset. 图片和视频资源的部件构建

initState(AssetPickerState<Asset, Path> state) → void

Keep a initState method to sync with State. 保留一个 initState 方法与 State 同步。

interactiveTextColor(BuildContext context) → Color

The color for interactive texts. 可交互的文字的颜色

iOSPermissionOverlay(BuildContext context) → Widget

The overlay when the permission is limited on iOS.

isAppleOS(BuildContext context) → bool

Whether the current platform is Apple OS. 当前平台是否苹果系列系统 (iOS & MacOS)

itemBannedIndicator(BuildContext context, Asset asset) → Widget

Indicator when the asset cannot be selected. 当资源无法被选中时的遮罩

loadingIndicator(BuildContext context) → Widget

Loading indicator. 加载指示器

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

onAssetsChanged(MethodCall call, StateSetter setState) → Future<void>

Called when assets changed and obtained notifications from the OS. 系统发出资源变更的通知时调用的方法

pathEntityListBackdrop(BuildContext context) → Widget

A backdrop widget behind the pathEntityListWidget. 在 pathEntityListWidget 后面的遮罩层

pathEntityListWidget(BuildContext context) → Widget

List widget for path entities. 路径选择列表组件

pathEntitySelector(BuildContext context) → Widget

Path entity select widget builder. 路径选择部件构建

pathEntityWidget({required BuildContext context, required List<PathWrapper<Path>> list, required int index}) → Widget

Item widgets for path entity selector. 路径单独条目选择组件

permissionOverlay(BuildContext context) → Widget

The overlay when the permission is limited.

previewButton(BuildContext context) → Widget

Preview button to preview selected assets. 预览已选资源的按钮

selectAsset(BuildContext context, Asset asset, int index, bool selected) → void

The method to select assets. Delegates can implement this method to involve with predications, callbacks, etc. 选择资源的方法。自定义的 delegate 可以通过实现该方法，整合判断、回调等操作。

selectedBackdrop(BuildContext context, int index, Asset asset) → Widget

Animated backdrop widget for items. 部件选中时的动画遮罩部件

selectIndicator(BuildContext context, int index, Asset asset) → Widget

Indicator for assets selected status. 资源是否已选的指示器

toString() → String

A string representation of this object.

inherited

videoIndicator(BuildContext context, Asset asset) → Widget

Video asset type indicator. 视频类型资源指示

viewAsset(BuildContext context, int? index, Asset currentAsset) → Future<void>

Determine how to browse assets in the viewer. 定义如何在查看器中浏览资源

Operators

operator ==(Object other) → bool

The equality operator.

inherited