HTML5 Mobile Website Development page Width solution

I believe we all know that the current market on the screen size of a variety of mobile phones, 2.8-inch, 3.0-inch, 3.2-inch, 3.5-inch, 4.0-inch, 4.2-inch, 4.5-inch, and so on, the phone with the resolution is also very different, there are 240*320 pixels, 320*480 pixels, 480*800 pixels, 640*960 pixels and so on, of which 480*800 pixels and 640*960 pixels are mainstream, but the speed of the development of smart phones are obvious to all, with the development of mobile phones, different sizes of mobile phones will appear, which will give the development of mobile web site to bring very big trouble, How to make their own mobile phone site in different sizes of mobile phones can be a perfect display, mobile phone site design to design how big to fit?

As long as a little attention to the Internet, should be aware of the strong HTML5,HTML5, because the PC website browser update is too difficult, resulting in poor compatibility, so HTML5 new technology in the PC site is difficult to implement, but the mobile browser update very quickly, the basic can be perfectly supported html5+ CSS3. Here, the square-dimensional network describes how a viewport feature of HTML5 allows the website to adapt to different resolutions of the mobile browser.

The viewport syntax is as follows:
<!--HTML Document--
<meta name= "Viewport"
Content= "
Height = [Pixel_value | device-height],
width = [Pixel_value | device-width],
Initial-scale = Float_value,
Minimum-scale = Float_value,
Maximum-scale = Float_value,
user-scalable = [yes | no],
Ten target-densitydpi = [Dpi_value | device-dpi | high-dpi | medium-dpi | low-dpi]
11 "
/>

One.

Width
Controls the size of the viewport, you can specify a value or a special value, such as device-width as the width of the device (in pixels of the CSS when scaled to 100%).

Two.

Height
Corresponds to width, specifying the height.

Three.

target-densitydpi
A screen pixel density is determined by the screen resolution, usually defined as the number of dots per inch (dpi). Android supports three screen pixel densities: low pixel density, medium pixel density, high pixel density. A low-pixel-density screen has fewer pixels per inch, while a high-pixel-density screen has more pixels per inch. The default screen for Android browser and webview is medium pixel density.

The following is the range of values for the Target-densitydpi property

The device-dpi– uses the original DPI of the device as the target DP. No default scaling occurs.
high-dpi– uses hdpi as the target dpi. Medium pixel density and low pixel density devices are scaled down accordingly.
medium-dpi– uses MDPI as the target dpi. High pixel density devices are scaled accordingly, and pixel density devices are scaled down accordingly. This is the default target density.
LOW-DPI-use MDPI as the target dpi. Medium pixel density and high pixel density devices are scaled accordingly.
<value>– specifies a specific DPI value as the target dpi. The range of this value must be between 70–400.
1 <!--HTML Document--
2 <meta name= "viewport" content= "target-densitydpi=device-dpi"/>
3 <meta name= "viewport" content= "target-densitydpi=high-dpi"/>
4 <meta name= "viewport" content= "target-densitydpi=medium-dpi"/>
5 <meta name= "viewport" content= "target-densitydpi=low-dpi"/>
6 <meta name= "viewport" content= "target-densitydpi=200"/>
To prevent Android browser and WebView from scaling your page based on the pixel density of different screens, you can set the target-densitydpi of viewport to device-dpi. When you do this, the page will not scale. Instead, the page is displayed based on the pixel density of the current screen. In this case, you also need to define the width of the viewport to match the width of the device so that your page will fit on the screen.

Four.

Initial-scale
Initial scaling. That is, the initial zoom level of the page. This is a floating-point value, which is a multiplier of the page size. For example, if you set the initial zoom to "1.0", then the Web page will show up at 1:1 of the target density resolution. If you set it to "2.0", the page will be enlarged to twice times.

Five.

Maximum-scale
Maximum zoom. That is, the maximum allowable zoom level. This is also a floating-point value that indicates the maximum multiplier of the page size compared to the screen size. For example, if you set this value to "2.0", the page can be up to twice times larger than the target size.

Six.

User-scalable
The user adjusts the zoom. That is, whether the user can change the page zoom level. If set to Yes, the user is allowed to change it instead of No. The default value is yes. If you set it to No, then both Minimum-scale and Maximum-scale will be ignored because scaling is not possible at all.

All scaling values must be within the range of the 0.01–10.

Cases:

(Set screen width to device width, prevent users from manually resizing)

<meta name= "viewport" content= "Width=device-width,user-scalable=no"/>

(Set the screen density to high frequency, if, low frequency auto-scaling, prohibit the user to manually adjust the zoom)

<meta name= "viewport" content= "width=device-width,target-densitydpi=high-dpi,initial-scale=1.0, minimum-scale= 1.0, maximum-scale=1.0, User-scalable=no "/>