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/* * Copyright (C) 2006 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package android.util; import android.annotation.UnsupportedAppUsage; import android.os.SystemProperties; /** * A structure describing general information about a display, such as its * size, density, and font scaling. * <p>To access the DisplayMetrics members, initialize an object like this:</p> * <pre> DisplayMetrics metrics = new DisplayMetrics(); * getWindowManager().getDefaultDisplay().getMetrics(metrics);</pre> */ public class DisplayMetrics { /** * Standard quantized DPI for low-density screens. */ public static final int DENSITY_LOW = 120; /** * Standard quantized DPI for medium-density screens. */ public static final int DENSITY_MEDIUM = 160; /** * This is a secondary density, added for some common screen configurations. * It is recommended that applications not generally target this as a first * class density -- that is, don't supply specific graphics for this * density, instead allow the platform to scale from other densities * (typically {@link #DENSITY_HIGH}) as * appropriate. In most cases (such as using bitmaps in * {@link android.graphics.drawable.Drawable}) the platform * can perform this scaling at load time, so the only cost is some slight * startup runtime overhead. * * <p>This density was original introduced to correspond with a * 720p TV screen: the density for 1080p televisions is * {@link #DENSITY_XHIGH}, and the value here provides the same UI * size for a TV running at 720p. It has also found use in 7" tablets, * when these devices have 1280x720 displays. */ public static final int DENSITY_TV = 213; /** * Standard quantized DPI for high-density screens. */ public static final int DENSITY_HIGH = 240; /** * Intermediate density for screens that sit between {@link #DENSITY_HIGH} (240dpi) and * {@link #DENSITY_XHIGH} (320dpi). This is not a density that applications should target, * instead relying on the system to scale their {@link #DENSITY_XHIGH} assets for them. */ public static final int DENSITY_260 = 260; /** * Intermediate density for screens that sit between {@link #DENSITY_HIGH} (240dpi) and * {@link #DENSITY_XHIGH} (320dpi). This is not a density that applications should target, * instead relying on the system to scale their {@link #DENSITY_XHIGH} assets for them. */ public static final int DENSITY_280 = 280; /** * Intermediate density for screens that sit between {@link #DENSITY_HIGH} (240dpi) and * {@link #DENSITY_XHIGH} (320dpi). This is not a density that applications should target, * instead relying on the system to scale their {@link #DENSITY_XHIGH} assets for them. */ public static final int DENSITY_300 = 300; /** * Standard quantized DPI for extra-high-density screens. */ public static final int DENSITY_XHIGH = 320; /** * Intermediate density for screens that sit somewhere between * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). * This is not a density that applications should target, instead relying * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. */ public static final int DENSITY_340 = 340; /** * Intermediate density for screens that sit somewhere between * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). * This is not a density that applications should target, instead relying * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. */ public static final int DENSITY_360 = 360; /** * Intermediate density for screens that sit somewhere between * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). * This is not a density that applications should target, instead relying * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. */ public static final int DENSITY_400 = 400; /** * Intermediate density for screens that sit somewhere between * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). * This is not a density that applications should target, instead relying * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. */ public static final int DENSITY_420 = 420; /** * Intermediate density for screens that sit somewhere between * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). * This is not a density that applications should target, instead relying * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. */ public static final int DENSITY_440 = 440; /** * Standard quantized DPI for extra-extra-high-density screens. */ public static final int DENSITY_XXHIGH = 480; /** * Intermediate density for screens that sit somewhere between * {@link #DENSITY_XXHIGH} (480 dpi) and {@link #DENSITY_XXXHIGH} (640 dpi). * This is not a density that applications should target, instead relying * on the system to scale their {@link #DENSITY_XXXHIGH} assets for them. */ public static final int DENSITY_560 = 560; /** * Intermediate density for screens that sit somewhere between * {@link #DENSITY_XXHIGH} (480 dpi) and {@link #DENSITY_XXXHIGH} (640 dpi). * This is not a density that applications should target, instead relying * on the system to scale their {@link #DENSITY_XXXHIGH} assets for them. */ public static final int DENSITY_600 = 600; /** * Standard quantized DPI for extra-extra-extra-high-density screens. Applications * should not generally worry about this density; relying on XHIGH graphics * being scaled up to it should be sufficient for almost all cases. A typical * use of this density would be 4K television screens -- 3840x2160, which * is 2x a traditional HD 1920x1080 screen which runs at DENSITY_XHIGH. */ public static final int DENSITY_XXXHIGH = 640; /** * The reference density used throughout the system. */ public static final int DENSITY_DEFAULT = DENSITY_MEDIUM; /** * Scaling factor to convert a density in DPI units to the density scale. * @hide */ public static final float DENSITY_DEFAULT_SCALE = 1.0f / DENSITY_DEFAULT; /** * The device's current density. * <p> * This value reflects any changes made to the device density. To obtain * the device's stable density, use {@link #DENSITY_DEVICE_STABLE}. * * @hide This value should not be used. * @deprecated Use {@link #DENSITY_DEVICE_STABLE} to obtain the stable * device density or {@link #densityDpi} to obtain the current * density for a specific display. */ @Deprecated @UnsupportedAppUsage public static int DENSITY_DEVICE = getDeviceDensity(); /** * The device's stable density. * <p> * This value is constant at run time and may not reflect the current * display density. To obtain the current density for a specific display, * use {@link #densityDpi}. */ public static final int DENSITY_DEVICE_STABLE = getDeviceDensity(); /** * The absolute width of the available display size in pixels. */ public int widthPixels; /** * The absolute height of the available display size in pixels. */ public int heightPixels; /** * The logical density of the display. This is a scaling factor for the * Density Independent Pixel unit, where one DIP is one pixel on an * approximately 160 dpi screen (for example a 240x320, 1.5"x2" screen), * providing the baseline of the system's display. Thus on a 160dpi screen * this density value will be 1; on a 120 dpi screen it would be .75; etc. * * <p>This value does not exactly follow the real screen size (as given by * {@link #xdpi} and {@link #ydpi}, but rather is used to scale the size of * the overall UI in steps based on gross changes in the display dpi. For * example, a 240x320 screen will have a density of 1 even if its width is * 1.8", 1.3", etc. However, if the screen resolution is increased to * 320x480 but the screen size remained 1.5"x2" then the density would be * increased (probably to 1.5). * * @see #DENSITY_DEFAULT */ public float density; /** * The screen density expressed as dots-per-inch. May be either * {@link #DENSITY_LOW}, {@link #DENSITY_MEDIUM}, or {@link #DENSITY_HIGH}. */ public int densityDpi; /** * A scaling factor for fonts displayed on the display. This is the same * as {@link #density}, except that it may be adjusted in smaller * increments at runtime based on a user preference for the font size. */ public float scaledDensity; /** * The exact physical pixels per inch of the screen in the X dimension. */ public float xdpi; /** * The exact physical pixels per inch of the screen in the Y dimension. */ public float ydpi; /** * The reported display width prior to any compatibility mode scaling * being applied. * @hide */ @UnsupportedAppUsage public int noncompatWidthPixels; /** * The reported display height prior to any compatibility mode scaling * being applied. * @hide */ @UnsupportedAppUsage public int noncompatHeightPixels; /** * The reported display density prior to any compatibility mode scaling * being applied. * @hide */ public float noncompatDensity; /** * The reported display density prior to any compatibility mode scaling * being applied. * @hide */ @UnsupportedAppUsage public int noncompatDensityDpi; /** * The reported scaled density prior to any compatibility mode scaling * being applied. * @hide */ public float noncompatScaledDensity; /** * The reported display xdpi prior to any compatibility mode scaling * being applied. * @hide */ public float noncompatXdpi; /** * The reported display ydpi prior to any compatibility mode scaling * being applied. * @hide */ public float noncompatYdpi; public DisplayMetrics() { } public void setTo(DisplayMetrics o) { if (this == o) { return; } widthPixels = o.widthPixels; heightPixels = o.heightPixels; density = o.density; densityDpi = o.densityDpi; scaledDensity = o.scaledDensity; xdpi = o.xdpi; ydpi = o.ydpi; noncompatWidthPixels = o.noncompatWidthPixels; noncompatHeightPixels = o.noncompatHeightPixels; noncompatDensity = o.noncompatDensity; noncompatDensityDpi = o.noncompatDensityDpi; noncompatScaledDensity = o.noncompatScaledDensity; noncompatXdpi = o.noncompatXdpi; noncompatYdpi = o.noncompatYdpi; } public void setToDefaults() { widthPixels = 0; heightPixels = 0; density = DENSITY_DEVICE / (float) DENSITY_DEFAULT; densityDpi = DENSITY_DEVICE; scaledDensity = density; xdpi = DENSITY_DEVICE; ydpi = DENSITY_DEVICE; noncompatWidthPixels = widthPixels; noncompatHeightPixels = heightPixels; noncompatDensity = density; noncompatDensityDpi = densityDpi; noncompatScaledDensity = scaledDensity; noncompatXdpi = xdpi; noncompatYdpi = ydpi; } @Override public boolean equals(Object o) { return o instanceof DisplayMetrics && equals((DisplayMetrics) o); } /** * Returns true if these display metrics equal the other display metrics. * * @param other The display metrics with which to compare. * @return True if the display metrics are equal. */ public boolean equals(DisplayMetrics other) { return equalsPhysical(other) && scaledDensity == other.scaledDensity && noncompatScaledDensity == other.noncompatScaledDensity; } /** * Returns true if the physical aspects of the two display metrics * are equal. This ignores the scaled density, which is a logical * attribute based on the current desired font size. * * @param other The display metrics with which to compare. * @return True if the display metrics are equal. * @hide */ public boolean equalsPhysical(DisplayMetrics other) { return other != null && widthPixels == other.widthPixels && heightPixels == other.heightPixels && density == other.density && densityDpi == other.densityDpi && xdpi == other.xdpi && ydpi == other.ydpi && noncompatWidthPixels == other.noncompatWidthPixels && noncompatHeightPixels == other.noncompatHeightPixels && noncompatDensity == other.noncompatDensity && noncompatDensityDpi == other.noncompatDensityDpi && noncompatXdpi == other.noncompatXdpi && noncompatYdpi == other.noncompatYdpi; } @Override public int hashCode() { return widthPixels * heightPixels * densityDpi; } @Override public String toString() { return "DisplayMetrics{density=" + density + ", width=" + widthPixels + ", height=" + heightPixels + ", scaledDensity=" + scaledDensity + ", xdpi=" + xdpi + ", ydpi=" + ydpi + "}"; } private static int getDeviceDensity() { // qemu.sf.lcd_density can be used to override ro.sf.lcd_density // when running in the emulator, allowing for dynamic configurations. // The reason for this is that ro.sf.lcd_density is write-once and is // set by the init process when it parses build.prop before anything else. return SystemProperties.getInt("qemu.sf.lcd_density", SystemProperties.getInt("ro.sf.lcd_density", DENSITY_DEFAULT)); } }