Android開發之dp、sp、px轉換-SizeUtils

對於開發中dp、px間的轉換，sp、px間的轉換，獲取view測量寬度和高度，進行彙總

dp轉px

public static int dp2px(final float dpValue) {
        final float scale = Utils.getApp().getResources().getDisplayMetrics().density;
        return (int) (dpValue * scale + 0.5f);
}

px轉dp

public static int px2dp(final float pxValue) {
        final float scale = Utils.getApp().getResources().getDisplayMetrics().density;
        return (int) (pxValue / scale + 0.5f);
}

px轉sp

public static int px2sp(final float pxValue) {
        final float fontScale = Utils.getApp().getResources().getDisplayMetrics().scaledDensity;
        return (int) (pxValue / fontScale + 0.5f);
}

sp轉px

public static int sp2px(final float spValue) {
        final float fontScale = Utils.getApp().getResources().getDisplayMetrics().scaledDensity;
        return (int) (spValue * fontScale + 0.5f);
}

指定dimens大小以及單位

public static float applyDimension(final float value, final int unit) {
        DisplayMetrics metrics = Utils.getApp().getResources().getDisplayMetrics();
        switch (unit) {
            case TypedValue.COMPLEX_UNIT_PX:
                return value;
            case TypedValue.COMPLEX_UNIT_DIP:
                return value * metrics.density;
            case TypedValue.COMPLEX_UNIT_SP:
                return value * metrics.scaledDensity;
            case TypedValue.COMPLEX_UNIT_PT:
                return value * metrics.xdpi * (1.0f / 72);
            case TypedValue.COMPLEX_UNIT_IN:
                return value * metrics.xdpi;
            case TypedValue.COMPLEX_UNIT_MM:
                return value * metrics.xdpi * (1.0f / 25.4f);
        }
        return 0;
}

獲取view測量寬度

public static int getMeasuredWidth(final View view) {
        return measureView(view)[0];
}

獲取view測量高度

public static int getMeasuredHeight(final View view) {
        return measureView(view)[1];
}

獲取view的測量寬高

 public static int[] measureView(final View view) {
        ViewGroup.LayoutParams lp = view.getLayoutParams();
        if (lp == null) {
            lp = new ViewGroup.LayoutParams(
                    ViewGroup.LayoutParams.MATCH_PARENT,
                    ViewGroup.LayoutParams.WRAP_CONTENT
            );
        }
        int widthSpec = ViewGroup.getChildMeasureSpec(0, 0, lp.width);
        int lpHeight = lp.height;
        int heightSpec;
        if (lpHeight > 0) {
            heightSpec = View.MeasureSpec.makeMeasureSpec(lpHeight, View.MeasureSpec.EXACTLY);
        } else {
            heightSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
        }
        view.measure(widthSpec, heightSpec);
        return new int[]{view.getMeasuredWidth(), view.getMeasuredHeight()};
}