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;
}