@mdrajibul/zoomify
Version:
A simple zoomify image library
165 lines (163 loc) • 7.62 kB
JavaScript
;
/**
A simple utility class to zoomify background image
@param container - HTMLElement
@param autoStop - Set true to stop automatically when use mouse out. false to control from outside
@returns IMagnifyImage */
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
return new (P || (P = Promise))(function (resolve, reject) {
function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments || [])).next());
});
};
var __generator = (this && this.__generator) || function (thisArg, body) {
var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;
return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g;
function verb(n) { return function (v) { return step([n, v]); }; }
function step(op) {
if (f) throw new TypeError("Generator is already executing.");
while (_) try {
if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
if (y = 0, t) op = [op[0] & 2, t.value];
switch (op[0]) {
case 0: case 1: t = op; break;
case 4: _.label++; return { value: op[1], done: false };
case 5: _.label++; y = op[1]; op = [0]; continue;
case 7: op = _.ops.pop(); _.trys.pop(); continue;
default:
if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; }
if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; }
if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; }
if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; }
if (t[2]) _.ops.pop();
_.trys.pop(); continue;
}
op = body.call(thisArg, _);
} catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }
if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };
}
};
Object.defineProperty(exports, "__esModule", { value: true });
var Zoomify = /** @class */ (function () {
function Zoomify(container, autoStop) {
if (autoStop === void 0) { autoStop = false; }
this.imageUrl = '';
this.imageWidth = 0;
this.imageHeight = 0;
this.ratio = 0;
this.isLoaded = false;
this.container = container;
this.autoStop = autoStop;
var imageCss = window.getComputedStyle(container);
if (imageCss.backgroundImage) {
this.imageUrl = imageCss.backgroundImage.slice(4, -1).replace(/['"]/g, '');
}
this.imageSrc = new Image();
}
/**
* static function to start zoomify immediately
* @param container - A html element where to load
* @returns Promise<IZoomifyImage>
*/
Zoomify.run = function (container) {
var _this = this;
return new Promise(function (resolve) { return __awaiter(_this, void 0, void 0, function () {
var zoomify;
return __generator(this, function (_a) {
switch (_a.label) {
case 0:
zoomify = new Zoomify(container, true);
return [4 /*yield*/, zoomify.start()];
case 1:
_a.sent();
resolve(zoomify);
return [2 /*return*/];
}
});
}); });
};
/**
* Initialize image
* @returns Promise<boolean>
*/
Zoomify.prototype.init = function () {
var _this = this;
return new Promise(function (resolve) {
_this.imageSrc.onload = function () {
_this.imageWidth = _this.imageSrc.naturalWidth;
_this.imageHeight = _this.imageSrc.naturalHeight;
_this.ratio = _this.imageHeight / _this.imageWidth;
var percentage = _this.ratio * 100 + '%';
_this.container.style.paddingBottom = percentage;
_this.isLoaded = true;
};
_this.imageSrc.src = _this.imageUrl;
resolve(_this.isLoaded);
});
};
/**
* Start zoomify. Useful method to control from outside
*/
Zoomify.prototype.start = function () {
return __awaiter(this, void 0, void 0, function () {
return __generator(this, function (_a) {
switch (_a.label) {
case 0:
if (!!this.isLoaded) return [3 /*break*/, 2];
return [4 /*yield*/, this.init()];
case 1:
_a.sent();
_a.label = 2;
case 2:
this.afterLoad();
return [2 /*return*/];
}
});
});
};
/**
* Stop zoomify. Useful to control from outside
*/
Zoomify.prototype.stop = function () {
this.reset();
this.container.onmousemove = null;
this.container.onmouseout = null;
};
Zoomify.prototype.afterLoad = function () {
var _this = this;
this.container.style.cursor = 'crosshair';
this.container.onmousemove = function (ev) { return _this.move(ev, _this.ratio, _this.imageWidth); };
if (this.autoStop) {
this.container.onmouseout = function () { return _this.reset(); };
}
};
Zoomify.prototype.move = function (event, ratio, imageWidth) {
var scrollLeft = this.container.scrollLeft > 0
? this.container.scrollLeft
: this.container.parentElement && this.container.parentElement.scrollLeft > 0
? this.container.parentElement.scrollLeft
: 0;
var scrollTop = this.container.scrollTop > 0
? this.container.scrollTop
: this.container.parentElement && this.container.parentElement.scrollTop > 0
? this.container.parentElement.scrollTop
: 0;
var boxWidth = this.container.clientWidth, x = event.pageX - this.container.offsetLeft, y = event.pageY - this.container.offsetTop, xPercent = (x + scrollLeft) / (boxWidth / 100) + '%', yPercent = (y + scrollTop) / ((boxWidth * ratio) / 100) + '%';
Object.assign(this.container.style, {
backgroundPosition: xPercent + ' ' + yPercent,
backgroundSize: imageWidth + 'px',
});
};
Zoomify.prototype.reset = function () {
Object.assign(this.container.style, {
backgroundPosition: 'top',
backgroundSize: 'cover',
cursor: 'default',
});
};
return Zoomify;
}());
exports.Zoomify = Zoomify;