Android判断当前设备是手机还是平板以及dp与pix的转换

Android开发需要适配手机和平板，有些需求实现时就要求判断设备是手机还是平板。
网上很多说通过设备尺寸、DPI、版本号、是否具备电话功能等进行判断，不过都不算太精确。
这里分享一个简洁给力的方法（官方用法）：

/**
* 判断当前设备是手机还是平板，代码来自 Google I/O App for Android
* @param context
* @return 平板返回 True，手机返回 False
*/
public static boolean isPad(Context context) {
return (context.getResources().getConfiguration().screenLayout
& Configuration.SCREENLAYOUT_SIZE_MASK)
>= Configuration.SCREENLAYOUT_SIZE_LARGE;
}

令附上是否具备电话功能判断方法（现在部分平板也可以打电话）：

public static boolean isPad(Activity activity) {
TelephonyManager telephony = (TelephonyManager)activity.getSystemService(Context.TELEPHONY_SERVICE);
if (telephony.getPhoneType() == TelephonyManager.PHONE_TYPE_NONE) {
return true;
}else {
return false;
}
}

 

至于设备尺寸、分辨率、版本号，以目前手机来看，个人认为精度太差了，不建议使用。

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/**
* This method converts dp unit to equivalent pixels, depending on device density.
*
* @param dp A value in dp (density independent pixels) unit. Which we need to convert into pixels
* @param context Context to get resources and device specific display metrics
* @return A float value to represent px equivalent to dp depending on device density
*/
public static float convertDpToPixel(float dp, Context context){
Resources resources = context.getResources();
DisplayMetrics metrics = resources.getDisplayMetrics();
float px = dp * ((float)metrics.densityDpi / DisplayMetrics.DENSITY_DEFAULT);
return px;
}

/**
* This method converts device specific pixels to density independent pixels.
*
* @param px A value in px (pixels) unit. Which we need to convert into db
* @param context Context to get resources and device specific display metrics
* @return A float value to represent dp equivalent to px value
*/
public static float convertPixelsToDp(float px, Context context){
Resources resources = context.getResources();
DisplayMetrics metrics = resources.getDisplayMetrics();
float dp = px / ((float)metrics.densityDpi / DisplayMetrics.DENSITY_DEFAULT);
return dp;
}