我正在学习Angular2。我的目标是创建一个响应式应用程序,根据不同的设备宽度的媒体查询来加载不同的组件。我的工作示例有一个MatchMediaService:
import { Injectable } from '@angular/core';
@Injectable()
export class MatchMediaService
{
constructor()
{
}
rules =
{
print: "print",
screen: "screen",
phone: '(max-width: 767px)',
tablet: '(min-width: 768px) and (max-width: 1024px)',
desktop: '(min-width: 1025px)',
portrait: '(orientation: portrait)',
landscape: '(orientation: landscape)',
retina: '(-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi)'
};
Check = function (mq)
{
if (!mq)
{
return;
}
return window.matchMedia(mq).matches;
};
/**********************************************
METHODS FOR CHECKING TYPE
**********************************************/
IsPhone()
{
return window.matchMedia(this.rules.phone).matches;
};
IsTablet = function ()
{
return window.matchMedia(this.rules.tablet).matches;
};
IsDesktop = function ()
{
return window.matchMedia(this.rules.desktop).matches;
};
IsPortrait = function ()
{
return window.matchMedia(this.rules.portrait).matches;
};
IsLandscape = function ()
{
return window.matchMedia(this.rules.landscape).matches;
};
IsRetina = function ()
{
return window.matchMedia(this.rules.retina).matches;
};
/**********************************************
EVENT LISTENERS BY TYPE
**********************************************/
OnPhone(callBack)
{
if (typeof callBack === 'function')
{
var mql: MediaQueryList = window.matchMedia(this.rules.phone);
mql.addListener((mql: MediaQueryList) =>
{
if (mql.matches)
{
callBack(mql);
}
});
}
};
OnTablet(callBack)
{
if (typeof callBack === 'function')
{
var mql: MediaQueryList = window.matchMedia(this.rules.tablet);
mql.addListener((mql: MediaQueryList) =>
{
if (mql.matches)
{
callBack(mql);
}
});
}
};
OnDesktop(callBack)
{
if (typeof callBack === 'function')
{
var mql: MediaQueryList = window.matchMedia(this.rules.desktop);
mql.addListener((mql: MediaQueryList) =>
{
if (mql.matches)
{
callBack(mql);
}
});
}
};
OnPortrait(callBack)
{
if (typeof callBack === 'function')
{
var mql: MediaQueryList = window.matchMedia(this.rules.portrait);
mql.addListener((mql: MediaQueryList) =>
{
if (mql.matches)
{
callBack(mql);
}
});
}
};
OnLandscape(callBack)
{
if (typeof callBack === 'function')
{
var mql: MediaQueryList = window.matchMedia(this.rules.landscape);
mql.addListener((mql: MediaQueryList) =>
{
if (mql.matches)
{
callBack(mql);
}
});
}
};
}
然后,在一个“父”组件(HomeComponent)内,我使用MatchMediaService确定要加载哪个子组件(HomeMobileComponent或HomeDesktopComponent),具体取决于MatchMediaService返回的内容以及当浏览器通过不同尺寸调整大小时触发的侦听器事件:
import { Component, OnInit, NgZone } from '@angular/core';
import { MatchMediaService } from '../shared/services/match-media.service';
import { HomeMobileComponent } from './home-mobile.component';
import { HomeDesktopComponent } from './home-desktop.component';
@Component({
moduleId: module.id,
selector: 'home.component',
templateUrl: 'home.component.html',
providers: [ MatchMediaService ],
directives: [ HomeMobileComponent, HomeDesktopComponent ]
})
export class HomeComponent implements OnInit
{
IsMobile: Boolean = false;
IsDesktop: Boolean = false;
constructor(
private matchMediaService: MatchMediaService,
private zone: NgZone
)
{
//GET INITIAL VALUE BASED ON DEVICE WIDTHS AT TIME THE APP RENDERS
this.IsMobile = (this.matchMediaService.IsPhone() || this.matchMediaService.IsTablet());
this.IsDesktop = (this.matchMediaService.IsDesktop());
var that = this;
/*---------------------------------------------------
TAP INTO LISTENERS FOR WHEN DEVICE WIDTH CHANGES
---------------------------------------------------*/
this.matchMediaService.OnPhone(
function (mediaQueryList: MediaQueryList)
{
that.ShowMobile();
}
);
this.matchMediaService.OnTablet(
function (mediaQueryList: MediaQueryList)
{
that.ShowMobile();
}
);
this.matchMediaService.OnDesktop(
function (mediaQueryList: MediaQueryList)
{
that.ShowDesktop();
}
);
}
ngOnInit()
{
}
ShowMobile()
{
this.zone.run(() =>
{ // Change the property within the zone, CD will run after
this.IsMobile = true;
this.IsDesktop = false;
});
}
ShowDesktop()
{
this.zone.run(() =>
{ // Change the property within the zone, CD will run after
this.IsMobile = false;
this.IsDesktop = true;
});
}
}
<home-mobile *ngIf="(IsMobile)"></home-mobile>
<home-desktop *ngIf="(IsDesktop)"></home-desktop>
这种方法可行。我可以根据设备加载适当的组件。它使我能够根据设备定制组件(内容、样式、功能等),从而实现最佳用户体验。这也使我能够针对移动设备、平板电脑和桌面电脑选择不同的组件(尽管在示例中我只关注移动设备和桌面电脑)。
是否有更好的方法?缺点是我强制每个组件都由父组件组成,以通过MatchMediaService确定要加载哪个子组件。这种方法在完整的生产级应用程序中是否可扩展?我非常希望得到您的反馈,看看是否有更好的方法,或者这种方法是否可接受并且可扩展到完整的生产应用程序中。感谢您的反馈。
@View()
原本应该在这方面有所帮助,但因为效果不佳而被放弃了。 - Günter Zöchbauer