如何获得屏幕密度编程在android?

我的意思是:如何找到当前设备的屏幕dpi ?


当前回答

你应该试试这个。刚刚添加了一个方法,它将找到并显示吐司。设备属于哪个类别。

public static int differentDensityAndScreenSize(Context context) {
  int value = 20;
  String str = "";
  if ((context.getResources().getConfiguration().screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_SMALL) {
   switch (context.getResources().getDisplayMetrics().densityDpi) {
   case DisplayMetrics.DENSITY_LOW:
    str = "small-ldpi";
    value = 20;
    break;
   case DisplayMetrics.DENSITY_MEDIUM:
    str = "small-mdpi";
    value = 20;
    break;
   case DisplayMetrics.DENSITY_HIGH:
    str = "small-hdpi";
    value = 20;
    break;
   case DisplayMetrics.DENSITY_XHIGH:
    str = "small-xhdpi";
    value = 20;
    break;
   case DisplayMetrics.DENSITY_XXHIGH:
    str = "small-xxhdpi";
    value = 20;
    break;
   case DisplayMetrics.DENSITY_XXXHIGH:
    str = "small-xxxhdpi";
    value = 20;
    break;
   case DisplayMetrics.DENSITY_TV:
    str = "small-tvdpi";
    value = 20;
    break;
   default:
    str = "small-unknown";
    value = 20;
    break;
   }

  } else if ((context.getResources().getConfiguration().screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_NORMAL) {
   switch (context.getResources().getDisplayMetrics().densityDpi) {
   case DisplayMetrics.DENSITY_LOW:
    str = "normal-ldpi";
    value = 82;
    break;
   case DisplayMetrics.DENSITY_MEDIUM:
    str = "normal-mdpi";
    value = 82;
    break;
   case DisplayMetrics.DENSITY_HIGH:
    str = "normal-hdpi";
    value = 82;
    break;
   case DisplayMetrics.DENSITY_XHIGH:
    str = "normal-xhdpi";
    value = 90;
    break;
   case DisplayMetrics.DENSITY_XXHIGH:
    str = "normal-xxhdpi";
    value = 96;
    break;
   case DisplayMetrics.DENSITY_XXXHIGH:
    str = "normal-xxxhdpi";
    value = 96;
    break;
   case DisplayMetrics.DENSITY_TV:
    str = "normal-tvdpi";
    value = 96;
    break;
   default:
    str = "normal-unknown";
    value = 82;
    break;
   }
  } else if ((context.getResources().getConfiguration().screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_LARGE) {
   switch (context.getResources().getDisplayMetrics().densityDpi) {
   case DisplayMetrics.DENSITY_LOW:
    str = "large-ldpi";
    value = 78;
    break;
   case DisplayMetrics.DENSITY_MEDIUM:
    str = "large-mdpi";
    value = 78;
    break;
   case DisplayMetrics.DENSITY_HIGH:
    str = "large-hdpi";
    value = 78;
    break;
   case DisplayMetrics.DENSITY_XHIGH:
    str = "large-xhdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_XXHIGH:
    str = "large-xxhdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_XXXHIGH:
    str = "large-xxxhdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_TV:
    str = "large-tvdpi";
    value = 125;
    break;
   default:
    str = "large-unknown";
    value = 78;
    break;
   }

  } else if ((context.getResources().getConfiguration().screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_XLARGE) {
   switch (context.getResources().getDisplayMetrics().densityDpi) {
   case DisplayMetrics.DENSITY_LOW:
    str = "xlarge-ldpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_MEDIUM:
    str = "xlarge-mdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_HIGH:
    str = "xlarge-hdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_XHIGH:
    str = "xlarge-xhdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_XXHIGH:
    str = "xlarge-xxhdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_XXXHIGH:
    str = "xlarge-xxxhdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_TV:
    str = "xlarge-tvdpi";
    value = 125;
    break;
   default:
    str = "xlarge-unknown";
    value = 125;
    break;
   }
  }
// The Toast will show the Device falls in Which Categories.
Toast.makeText(MainActivity.this, ""+str, Toast.LENGTH_SHORT).show();

  return value;
 }

http://www.androidwarriors.com/2016/01/how-to-find-different-devices-screen.html

其他回答

你可以从DisplayMetrics结构体中获取显示信息:

DisplayMetrics metrics = getResources().getDisplayMetrics();

虽然Android不使用直接的像素映射,但它使用了少量量化的密度无关像素值,然后缩放到实际的屏幕尺寸。因此metrics.densityDpi属性将是DENSITY_xxx常量之一(120,160,213,240,320,480或640 dpi)。

如果你需要实际的lcd像素密度(也许对于OpenGL应用程序),你可以从指标中得到它。Xdpi和度量。水平密度和垂直密度的Ydpi特性。

如果你的目标API级别早于4。metrics.density属性是一个来自参考密度(160dpi)的浮点比例因子。现在可以计算metrics.densityDpi提供的相同值

int densityDpi = (int)(metrics.density * 160f);

在Android中,你可以得到这样的屏幕密度:

public static String getScreenDensity(Context context)
{
    String density;
    switch (context.getResources().getDisplayMetrics().densityDpi)
    {
        case DisplayMetrics.DENSITY_LOW:
            density = "LDPI";
            break;
        case DisplayMetrics.DENSITY_140:
            density = "LDPI - MDPI";
            break;
        case DisplayMetrics.DENSITY_MEDIUM:
            density = "MDPI";
            break;
        case DisplayMetrics.DENSITY_180:
        case DisplayMetrics.DENSITY_200:
        case DisplayMetrics.DENSITY_220:
            density = "MDPI - HDPI";
            break;
        case DisplayMetrics.DENSITY_HIGH:
            density = "HDPI";
            break;
        case DisplayMetrics.DENSITY_260:
        case DisplayMetrics.DENSITY_280:
        case DisplayMetrics.DENSITY_300:
            density = "HDPI - XHDPI";
            break;
        case DisplayMetrics.DENSITY_XHIGH:
            density = "XHDPI";
            break;
        case DisplayMetrics.DENSITY_340:
        case DisplayMetrics.DENSITY_360:
        case DisplayMetrics.DENSITY_400:
        case DisplayMetrics.DENSITY_420:
        case DisplayMetrics.DENSITY_440:
            density = "XHDPI - XXHDPI";
            break;
        case DisplayMetrics.DENSITY_XXHIGH:
            density = "XXHDPI";
            break;
        case DisplayMetrics.DENSITY_560:
        case DisplayMetrics.DENSITY_600:
            density = "XXHDPI - XXXHDPI";
            break;
        case DisplayMetrics.DENSITY_XXXHIGH:
            density = "XXXHDPI";
            break;
        case DisplayMetrics.DENSITY_TV:
            density = "TVDPI";
            break;
        default:
            density = "UNKNOWN";
            break;
    }

    return density;
}

在Kotlin中是这样的:

fun getScreenDensity(context: Context): String {
    val density: String
    when (context.resources.displayMetrics.densityDpi) {
        DisplayMetrics.DENSITY_LOW -> density = "LDPI"
        DisplayMetrics.DENSITY_140 -> density = "LDPI - MDPI"
        DisplayMetrics.DENSITY_MEDIUM -> density = "MDPI"
        DisplayMetrics.DENSITY_180, DisplayMetrics.DENSITY_200, DisplayMetrics.DENSITY_220 -> density = "MDPI - HDPI"
        DisplayMetrics.DENSITY_HIGH -> density = "HDPI"
        DisplayMetrics.DENSITY_260, DisplayMetrics.DENSITY_280, DisplayMetrics.DENSITY_300 -> density = "HDPI - XHDPI"
        DisplayMetrics.DENSITY_XHIGH -> density = "XHDPI"
        DisplayMetrics.DENSITY_340, DisplayMetrics.DENSITY_360, DisplayMetrics.DENSITY_400, DisplayMetrics.DENSITY_420, DisplayMetrics.DENSITY_440 -> density =
            "XHDPI - XXHDPI"
        DisplayMetrics.DENSITY_XXHIGH -> density = "XXHDPI"
        DisplayMetrics.DENSITY_560, DisplayMetrics.DENSITY_600 -> density = "XXHDPI - XXXHDPI"
        DisplayMetrics.DENSITY_XXXHIGH -> density = "XXXHDPI"
        DisplayMetrics.DENSITY_TV -> density = "TVDPI"
        else -> density = "UNKNOWN"
    }

    return density
}

确保定期检查是否增加了新的密度。

你应该试试这个。刚刚添加了一个方法,它将找到并显示吐司。设备属于哪个类别。

public static int differentDensityAndScreenSize(Context context) {
  int value = 20;
  String str = "";
  if ((context.getResources().getConfiguration().screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_SMALL) {
   switch (context.getResources().getDisplayMetrics().densityDpi) {
   case DisplayMetrics.DENSITY_LOW:
    str = "small-ldpi";
    value = 20;
    break;
   case DisplayMetrics.DENSITY_MEDIUM:
    str = "small-mdpi";
    value = 20;
    break;
   case DisplayMetrics.DENSITY_HIGH:
    str = "small-hdpi";
    value = 20;
    break;
   case DisplayMetrics.DENSITY_XHIGH:
    str = "small-xhdpi";
    value = 20;
    break;
   case DisplayMetrics.DENSITY_XXHIGH:
    str = "small-xxhdpi";
    value = 20;
    break;
   case DisplayMetrics.DENSITY_XXXHIGH:
    str = "small-xxxhdpi";
    value = 20;
    break;
   case DisplayMetrics.DENSITY_TV:
    str = "small-tvdpi";
    value = 20;
    break;
   default:
    str = "small-unknown";
    value = 20;
    break;
   }

  } else if ((context.getResources().getConfiguration().screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_NORMAL) {
   switch (context.getResources().getDisplayMetrics().densityDpi) {
   case DisplayMetrics.DENSITY_LOW:
    str = "normal-ldpi";
    value = 82;
    break;
   case DisplayMetrics.DENSITY_MEDIUM:
    str = "normal-mdpi";
    value = 82;
    break;
   case DisplayMetrics.DENSITY_HIGH:
    str = "normal-hdpi";
    value = 82;
    break;
   case DisplayMetrics.DENSITY_XHIGH:
    str = "normal-xhdpi";
    value = 90;
    break;
   case DisplayMetrics.DENSITY_XXHIGH:
    str = "normal-xxhdpi";
    value = 96;
    break;
   case DisplayMetrics.DENSITY_XXXHIGH:
    str = "normal-xxxhdpi";
    value = 96;
    break;
   case DisplayMetrics.DENSITY_TV:
    str = "normal-tvdpi";
    value = 96;
    break;
   default:
    str = "normal-unknown";
    value = 82;
    break;
   }
  } else if ((context.getResources().getConfiguration().screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_LARGE) {
   switch (context.getResources().getDisplayMetrics().densityDpi) {
   case DisplayMetrics.DENSITY_LOW:
    str = "large-ldpi";
    value = 78;
    break;
   case DisplayMetrics.DENSITY_MEDIUM:
    str = "large-mdpi";
    value = 78;
    break;
   case DisplayMetrics.DENSITY_HIGH:
    str = "large-hdpi";
    value = 78;
    break;
   case DisplayMetrics.DENSITY_XHIGH:
    str = "large-xhdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_XXHIGH:
    str = "large-xxhdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_XXXHIGH:
    str = "large-xxxhdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_TV:
    str = "large-tvdpi";
    value = 125;
    break;
   default:
    str = "large-unknown";
    value = 78;
    break;
   }

  } else if ((context.getResources().getConfiguration().screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_XLARGE) {
   switch (context.getResources().getDisplayMetrics().densityDpi) {
   case DisplayMetrics.DENSITY_LOW:
    str = "xlarge-ldpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_MEDIUM:
    str = "xlarge-mdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_HIGH:
    str = "xlarge-hdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_XHIGH:
    str = "xlarge-xhdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_XXHIGH:
    str = "xlarge-xxhdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_XXXHIGH:
    str = "xlarge-xxxhdpi";
    value = 125;
    break;
   case DisplayMetrics.DENSITY_TV:
    str = "xlarge-tvdpi";
    value = 125;
    break;
   default:
    str = "xlarge-unknown";
    value = 125;
    break;
   }
  }
// The Toast will show the Device falls in Which Categories.
Toast.makeText(MainActivity.this, ""+str, Toast.LENGTH_SHORT).show();

  return value;
 }

http://www.androidwarriors.com/2016/01/how-to-find-different-devices-screen.html

得到dpi:

DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);

// will either be DENSITY_LOW, DENSITY_MEDIUM or DENSITY_HIGH
int dpiClassification = dm.densityDpi;

// these will return the actual dpi horizontally and vertically
float xDpi = dm.xdpi;
float yDpi = dm.ydpi;

实际上,如果你想要真正的显示dpi,答案是介于两者之间 如果您查询显示指标:

DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);
int dpiClassification = dm.densityDpi;
float xDpi = dm.xdpi;
float yDpi = dm.ydpi;

densityDpi * 160会给出你应该使用哪种密度的值/建议

0.75 - ldpi - 120 dpi
1.0 - mdpi - 160 dpi
1.5 - hdpi - 240 dpi
2.0 - xhdpi - 320 dpi
3.0 - xxhdpi - 480 dpi
4.0 - xxxhdpi - 640 dpi

如之前的文章所述

但是dm.xdpi不会总是给你给定显示的真实dpi: 例子:

Device: Sony ericsson xperia mini pro (SK17i)
Density: 1.0 (e.g. suggests you use 160dpi resources)
xdpi: 193.5238
Real device ppi is arround 193ppi


Device: samsung GT-I8160 (Samsung ace 2)
Density 1.5 (e.g. suggests you use 240dpi resources)
xdpi 160.42105
Real device ppi is arround 246ppi

所以可能显示器的真实dpi应该是密度*xdpi ..但我不确定这是否是正确的做法!