I want to check this to fetch different imag开发者_JAVA百科es by internet. How to do that?
density = getResources().getDisplayMetrics().density;
// return 0.75 if it's LDPI
// return 1.0 if it's MDPI
// return 1.5 if it's HDPI
// return 2.0 if it's XHDPI
// return 3.0 if it's XXHDPI
// return 4.0 if it's XXXHDPI
You can check the screen density with:
switch (getResources().getDisplayMetrics().densityDpi) {
case DisplayMetrics.DENSITY_LOW:
// ...
break;
case DisplayMetrics.DENSITY_MEDIUM:
// ...
break;
case DisplayMetrics.DENSITY_HIGH:
// ...
break;
case DisplayMetrics.DENSITY_XHIGH:
// ...
break;
}
EDIT Be aware that as Android evolves, other values should be included in the switch
cases. As of this edit, this includes DisplayMetrics.DENSITY_TV
and DisplayMetrics.DENSITY_XXHIGH
. Consult the docs for the latest info; I'm not going to bother maintaining this answer.
As of 2018, you can use the below method -
public static String getDeviceDensityString(Context context) {
switch (context.getResources().getDisplayMetrics().densityDpi) {
case DisplayMetrics.DENSITY_LOW:
return "ldpi";
case DisplayMetrics.DENSITY_MEDIUM:
return "mdpi";
case DisplayMetrics.DENSITY_TV:
case DisplayMetrics.DENSITY_HIGH:
return "hdpi";
case DisplayMetrics.DENSITY_260:
case DisplayMetrics.DENSITY_280:
case DisplayMetrics.DENSITY_300:
case DisplayMetrics.DENSITY_XHIGH:
return "xhdpi";
case DisplayMetrics.DENSITY_340:
case DisplayMetrics.DENSITY_360:
case DisplayMetrics.DENSITY_400:
case DisplayMetrics.DENSITY_420:
case DisplayMetrics.DENSITY_440:
case DisplayMetrics.DENSITY_XXHIGH:
return "xxhdpi";
case DisplayMetrics.DENSITY_560:
case DisplayMetrics.DENSITY_XXXHIGH:
return "xxxhdpi";
}
}
But as @Ted pointed always consult the official docs before using
From the above answers, I combined them and created the below function:
public static String getDeviceDensity(Context context){
String deviceDensity = "";
switch (context.getResources().getDisplayMetrics().densityDpi) {
case DisplayMetrics.DENSITY_LOW:
deviceDensity = 0.75 + " ldpi";
break;
case DisplayMetrics.DENSITY_MEDIUM:
deviceDensity = 1.0 + " mdpi";
break;
case DisplayMetrics.DENSITY_HIGH:
deviceDensity = 1.5 + " hdpi";
break;
case DisplayMetrics.DENSITY_XHIGH:
deviceDensity = 2.0 + " xhdpi";
break;
case DisplayMetrics.DENSITY_XXHIGH:
deviceDensity = 3.0 + " xxhdpi";
break;
case DisplayMetrics.DENSITY_XXXHIGH:
deviceDensity = 4.0 + " xxxhdpi";
break;
default:
deviceDensity = "Not found";
}
return deviceDensity;
}
Now, on which device you want to get the density information and which folder it will be used, just add the above method in that activity and add the below line in onCreate
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
Log.d("Screen Density: ", Helper.getDeviceDensity(this));
}
You should always check the interval not only break point values!
According to android documentation: https://developer.android.com/reference/android/util/DisplayMetrics
Check it like this in Kotlin:
when {
val density: Float = context?.resources?.displayMetrics?.density
// ldpi
(density <= 0.75f) -> mulFactor = 0.75f
// mdpi
(density >= 0.75f && density <= 1.0f) -> mulFactor = 1.0f
// hdpi
(density > 1.0f && density <= 1.5f) -> mulFactor = 1.5f
// xhdpi
(density > 1.5f && density <= 2.0f) -> mulFactor = 2.0f
// xxhdpi
(density > 2.0f && density <= 3.0f) -> mulFactor = 3.0f
// xxxhdpi
(density > 3.0f) -> mulFactor = 4.0f
}
return mulFactor;
For React Native to check which size is currently of device
import { PixelRatio } from 'react-native';
switch(PixelRatio.get()) {
case 1:
return "mdpi";
case 1.5:
return "hdpi";
case 2:
return "xhdpi";
case 3:
return "xxhdpi";
case 3.5:
return "xxxhdpi";
}
On some devices (mine is Galaxy Tab3), both density and densityDpi return strange values like 1.33(density), 213(densityDpi). So my solution is to add these flag :
<item type="bool" name="is_mdpi">[bool]</item>
<item type="bool" name="is_hdpi">[bool]</item>
<item type="bool" name="is_xhdpi">[bool]</item>
<item type="bool" name="is_xxhdpi">[bool]</item>
to 4 values.xml files, put these under corresponding res/values-[xxx]/ folders.
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