鸿蒙媒体开发【拼图】拍照和图片

拼图

介绍

该示例通过@ohos.multimedia.image和@ohos.file.photoAccessHelper接口实现获取图片，以及图片裁剪分割的功能。

效果预览

使用说明：

使用预置相机拍照后启动应用，应用首页会读取设备内的图片文件并展示获取到的第一个图片，没有图片时图片位置显示空白；
点击开始按钮开始后，时间开始倒计时，在规定时间内未完成拼图则游戏结束。在游戏中，玩家点击重新开始进行游戏重置；
点击开始游戏后，玩家可以根据上方的大图，点击黄格周围的图片移动，点击后图片和黄格交换位置,最终拼成完整的图片；
不在游戏中时，玩家可以点击上方大图，选择自定义图片来进行拼图游戏。

具体实现

游戏中图片裁剪分割的效果实现在ImageModel中，源码参考[ImageModel]:

/** Copyright (c) 2022 Huawei Device Co., Ltd.* Licensed under the Apache License, Version 2.0 (the "License");* you may not use this file except in compliance with the License.* You may obtain a copy of the License at**     http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and* limitations under the License.*/import { image } from '@kit.ImageKit';
import { photoAccessHelper } from '@kit.MediaLibraryKit';
import { dataSharePredicates } from '@kit.ArkData';
import { Context } from '@kit.AbilityKit';
import { fileIo } from '@kit.CoreFileKit';
import Logger from './Logger';
import PictureItem from './PictureItem';
import { CommonConstants as Common } from '../common/CommonConstants';const TAG = '[ImageModel]';export default class ImageModel {private phAccessHelper: photoAccessHelper.PhotoAccessHelper | null = null;constructor(context: Context) {this.phAccessHelper = photoAccessHelper.getPhotoAccessHelper(context);}async getAllImg(): Promise<photoAccessHelper.PhotoAsset[]> {Logger.info('getAllImg');let photoList: Array<photoAccessHelper.PhotoAsset> = [];if (this.phAccessHelper === null) {Logger.info('phAccessHelper fail');return photoList;}let fileKeyType = photoAccessHelper.PhotoKeys.PHOTO_TYPE;let predicates: dataSharePredicates.DataSharePredicates = new dataSharePredicates.DataSharePredicates();Logger.info(fileKeyType);let fetchOptions: photoAccessHelper.FetchOptions = {fetchColumns: [],predicates: predicates};try {let fetchResult: photoAccessHelper.FetchResult<photoAccessHelper.PhotoAsset> =await this.phAccessHelper.getAssets(fetchOptions);if (fetchResult != undefined) {Logger.info('fetchResult success');let photoAsset: Array<photoAccessHelper.PhotoAsset> = await fetchResult.getAllObjects();if (photoAsset != undefined && photoAsset.length > 0) {for (let i = 0; i < photoAsset.length; i++) {if (photoAsset[i].photoType === 1) {photoList.push(photoAsset[i]);}}}}} catch (err) {Logger.error('getAssets failed, message = ', err);}Logger.info('photoList success');return photoList;}async splitPic(index: number): Promise<PictureItem[]> {let imagePixelMap: PictureItem[] = [];let imagesData: Array<photoAccessHelper.PhotoAsset> = await this.getAllImg();let imagePackerApi = image.createImagePacker();fileIo.open(imagesData[index].uri, fileIo.OpenMode.READ_ONLY).then(async (file: fileIo.File) => {let fd: number = file.fd;let imageSource = image.createImageSource(fd);let imageInfo = await imageSource.getImageInfo();Logger.info(TAG, `sizeImg createImageSource ${JSON.stringify(imageSource)}`);let height = imageInfo.size.height / Common.SPLIT_COUNT;for (let i = 0; i < Common.SPLIT_COUNT; i++) {for (let j = 0; j < Common.SPLIT_COUNT; j++) {let picItem: PictureItem;if (i === Common.SPLIT_COUNT - 1 && j === Common.SPLIT_COUNT - 1) {picItem = new PictureItem(Common.PICTURE_ITEM_NUMBER, {} as image.PixelMap);imagePixelMap.push(picItem);} else {Logger.info(TAG, `sizeImg x = ${imageInfo.size.width / Common.SPLIT_COUNT} y = ${height}`);let decodingOptions: image.DecodingOptions = {desiredRegion: {size: {height: height,width: imageInfo.size.width / Common.SPLIT_COUNT}, x: j * imageInfo.size.width / Common.SPLIT_COUNT, y: i * height}}imagePixelMap.push(new PictureItem(i * Common.SPLIT_COUNT + j, await imageSource.createPixelMap(decodingOptions)));}}}imagePackerApi.release();fileIo.closeSync(fd);})return imagePixelMap;}
}

获取本地图片：首先使用getPhotoAccessHelper获取相册管理模块实例，然后使用getAssets方法获取文件资源，最后使用getAllObjects获取检索结果中的所有文件资产方便展示；
裁剪图片准备：裁剪图片需要使用@ohos.multimedia.image接口，裁剪前需要申请图片编辑权限，使用requestPermissionsFromUser申请，源码参考[Index.ets];

/** Copyright (c) 2022-2023 Huawei Device Co., Ltd.* Licensed under the Apache License, Version 2.0 (the "License");* you may not use this file except in compliance with the License.* You may obtain a copy of the License at**     http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and* limitations under the License.*/import { mediaquery } from '@kit.ArkUI';
import { Permissions, abilityAccessCtrl } from '@kit.AbilityKit';
import { emitter } from '@kit.BasicServicesKit';
import { photoAccessHelper } from '@kit.MediaLibraryKit';
import GameRules from '../model/GameRules';
import ImagePicker from '../common/ImagePicker';
import Logger from '../model/Logger';
import PictureItem from '../model/PictureItem';
import ImageModel from '../model/ImageModel';
import { CommonConstants as Common } from '../common/CommonConstants';const PERMISSIONS: Array<Permissions> = ['ohos.permission.READ_MEDIA','ohos.permission.WRITE_MEDIA','ohos.permission.MEDIA_LOCATION','ohos.permission.MANAGE_MISSIONS'
];@Entry
@Component
struct Index {@State numArray: PictureItem[] = [];@State imgData: Array<photoAccessHelper.PhotoAsset> = [];@State @Watch('onTimeOver') gameTime: number = Common.GAME_TIME;@State @Watch('onImageChange') index: number = Common.ZERO;@State isLand: boolean = false;@StorageLink('isGameStart') isGameStart: boolean = false;private listener = mediaquery.matchMediaSync('screen and (min-aspect-ratio: 1.5) or (orientation: landscape)');private ImageModel: ImageModel = new ImageModel(getContext(this));private game: GameRules = new GameRules();private timer: number = -1;private isRefresh: boolean = false;onLand = (mediaQueryResult: mediaquery.MediaQueryResult) => {Logger.info(`[eTSMediaQuery.Index]onLand: mediaQueryResult.matches=${mediaQueryResult.matches}`);this.isLand = mediaQueryResult.matches;};over = () => {Logger.info(Common.TAG, 'emitter on , eventID = 0');for (let i = Common.ZERO; i < Common.LOOP; i++) {this.numArray[i].index = i;}this.gameOver();};timeEnd = () => {Logger.info(Common.TAG, 'emitter on , eventID = 1');this.gameTime = Common.ZERO;};async aboutToAppear() {this.listener.on('change', this.onLand);await abilityAccessCtrl.createAtManager().requestPermissionsFromUser(getContext(this), PERMISSIONS);this.imgData = await this.ImageModel.getAllImg();Logger.info(Common.TAG, `images = ${this.imgData.length}`);this.numArray = await this.ImageModel.splitPic(this.index);// Test case. The game is simulated successfully.emitter.on({ eventId: Common.ZERO, priority: Common.ZERO }, this.over);// Test case. End of simulation time.emitter.on({ eventId: Common.ONE, priority: Common.ZERO }, this.timeEnd);}onTimeOver() {if (this.gameTime === Common.ZERO) {this.isGameStart = false;AlertDialog.show({ message: 'TimeOver' });clearInterval(this.timer);}}async onImageChange() {this.isRefresh = true;this.dialogController.close();this.numArray = [];this.numArray = await this.ImageModel.splitPic(this.index);this.init();this.isGameStart = false;this.isRefresh = false;}init() {this.gameTime = Common.GAME_TIME;clearInterval(this.timer);}gameOver() {let count = Common.ZERO;for (let i = Common.ZERO; i < Common.LOOP; i++) {if (this.numArray[i].index === i) {count++;} else {count = Common.ZERO;break;}}if (count === Common.LOOP) {this.isGameStart = false;AlertDialog.show({ message: $r('app.string.congratulations') });clearInterval(this.timer);this.gameTime = Common.GAME_TIME;}}start() {this.init();this.timer = setInterval(() => {this.gameTime--;}, Common.TIME_NUMBER)}dialogController: CustomDialogController = new CustomDialogController({builder: ImagePicker({imagesData: this.imgData,index: $index}),autoCancel: true,gridCount: Common.GRID_COUNT})@BuilderImageShow() {Image(this.imgData[this.index].uri).id(Common.IMAGE_SHOW).width(Common.IMAGE_WIDTH).height($r('app.float.imageShow_height')).objectFit(ImageFit.Fill).onClick(async () => {if (this.isRefresh) {return;}this.imgData = await this.ImageModel.getAllImg();setTimeout(() => {this.dialogController.open();}, Common.TIME);})}@BuilderImageGrid(leftMargin: number, topMargin: number) {Grid() {ForEach(this.numArray, (item: PictureItem, index) => {GridItem() {Image(item.pixelMap).width(Common.GRID_IMAGE_WIDTH).objectFit(ImageFit.Fill).height($r('app.float.grid_image_height'))}.id(`image${index}`).backgroundColor(item.pixelMap === undefined ? $r('app.color.blank_picture_background') : $r('app.color.picture_background')).onClick(() => {if (this.isRefresh) {return;}if (this.isGameStart) {this.isRefresh = true;this.numArray = this.game.gameInit(index, this.numArray);this.gameOver();this.isRefresh = false;}})}, (item: PictureItem) => JSON.stringify(item))}.id(Common.IMAGE_GRID).columnsTemplate(Common.COLUMN_TEMPLATE).columnsGap($r('app.float.gap')).rowsGap($r('app.float.gap')).width(Common.IMAGE_WIDTH).height($r('app.float.grid_height')).margin({ left: leftMargin, top: topMargin })}build() {Column() {Row() {Text(`Time:0${Math.floor(this.gameTime / Common.SECOND)}:${this.gameTime % Common.SECOND < Common.TEN? Common.STRING_ZERO + this.gameTime % Common.SECOND : this.gameTime % Common.SECOND}`).id(Common.TIME_STRING).margin({ top: Common.MARGIN, bottom: Common.MARGIN })}if (this.imgData.length > Common.ZERO) {if (this.isLand) {Row() {this.ImageShow()this.ImageGrid(Common.TEN, Common.ZERO)}.margin({ top: Common.MARGIN })} else {Column() {this.ImageShow()this.ImageGrid(Common.ZERO, Common.FIVE)}.margin({ top: Common.MARGIN })}}Button($r('app.string.start'), { type: ButtonType.Capsule, stateEffect: true }).id(Common.START_BUTTON).height($r('app.float.button_height')).width(Common.FULL_WIDTH).fontSize($r('app.float.button_font_size')).margin({ top: Common.MARGIN }).backgroundColor(this.isGameStart ? $r('app.color.forbid') : $r('app.color.allow')).enabled(!this.isGameStart).onClick(() => {this.isGameStart = true;this.start();this.numArray = this.game.gameBegin(this.numArray);})Button($r('app.string.restart'), { type: ButtonType.Capsule, stateEffect: true }).id(Common.RESTART_BUTTON).height($r('app.float.button_height')).width(Common.FULL_WIDTH).fontSize($r('app.float.button_font_size')).margin({ top: Common.MARGIN }).backgroundColor(this.isGameStart ? $r('app.color.allow') : $r('app.color.forbid')).enabled(this.isGameStart).onClick(() => {this.isGameStart = true;this.start();this.numArray = this.game.gameBegin(this.numArray);})}.width(Common.FULL_WIDTH).height(Common.FULL_HEIGHT).padding({ left: Common.PERCENT, right: Common.PERCENT })}
}

图片编辑：首先使用createImagePacker创建ImagePacker实例，然后使用fs.open打开文件，调用createImageSource接口创建图片源实例方便操作图片，接下来使用getImageInfo方法获取图片大小便于分割，最后使用createPixelMap方法传入每一份的尺寸参数完成图片裁剪。

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