/*
* 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.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_280 = 280;
/**
* 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_400 = 400;
/**
* 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;
/**
* 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 density.
* @hide because eventually this should be able to change while
* running, so shouldn't be a constant.
* @deprecated There is no longer a static density; you can find the
* density for a display in {@link #densityDpi}.
*/
@Deprecated
public static int DENSITY_DEVICE = getDeviceDensity();
/**
* The absolute width of the display in pixels.
*/
public int widthPixels;
/**
* The absolute height of the display 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
*/
public int noncompatWidthPixels;
/**
* The reported display height prior to any compatibility mode scaling
* being applied.
* @hide
*/
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
*/
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) {
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));
}
}
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