How to calculate dp from pixels in android programmatically [duplicate]

问题

I want to calculate dp from px programmatically. How to do it? I get resolution from:

DisplayMetrics displaymetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
ht = displaymetrics.heightPixels;
wt = displaymetrics.widthPixels;

回答1:

All the answers here show a dp->px conversion rather than px->dp, which is what the OP asked for. Note that TypedValue.applyDimension cannot be used to convert px->dp, for that you must use the method described here: https://stackoverflow.com/a/17880012/504611 (quoted below for convenience).

Without Context object, elegant static methods:

public static int dpToPx(int dp) {
    return (int) (dp * Resources.getSystem().getDisplayMetrics().density);
}

public static int pxToDp(int px) {
    return (int) (px / Resources.getSystem().getDisplayMetrics().density);
}

回答2:

float ht_px = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, ht, getResources().getDisplayMetrics());
float wt_px = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, wt, getResources().getDisplayMetrics());

回答3:

This should give you the conversion pixels -> dp:

DisplayMetrics displaymetrics = new DisplayMetrics();
int dp = (int) TypedValue.applyDimension( TypedValue.COMPLEX_UNIT_DIP, myPixels, displaymetrics );

回答4:

DisplayMetrics dm = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(dm);
        String str_ScreenSize = "The Android Screen is: "
                    + dm.widthPixels
                    + " x "
                    + dm.heightPixels;

        TextView mScreenSize = (TextView) findViewById(R.id.strScreenSize);
        mScreenSize.setText(str_ScreenSize);

can u cheeck it out..

or this may also help u

int value = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 
                     (float) 123.4, getResources().getDisplayMetrics());

来源：https://stackoverflow.com/questions/8295986/how-to-calculate-dp-from-pixels-in-android-programmatically

标签

android

android-layout

resolution