1 /* 2 * Copyright (C) 2006 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.util; 18 19 import android.annotation.Nullable; 20 import android.compat.annotation.UnsupportedAppUsage; 21 import android.os.SystemProperties; 22 23 /** 24 * A structure describing general information about a display, such as its 25 * size, density, and font scaling. 26 * <p>To access the DisplayMetrics members, retrieve display metrics like this:</p> 27 * <pre>context.getResources().getDisplayMetrics();</pre> 28 */ 29 public class DisplayMetrics { 30 /** 31 * Standard quantized DPI for low-density screens. 32 */ 33 public static final int DENSITY_LOW = 120; 34 35 /** 36 * Intermediate density for screens that sit between {@link #DENSITY_LOW} (120dpi) and 37 * {@link #DENSITY_MEDIUM} (160dpi). This is not a density that applications should target, 38 * instead relying on the system to scale their {@link #DENSITY_MEDIUM} assets for them. 39 */ 40 public static final int DENSITY_140 = 140; 41 42 /** 43 * Standard quantized DPI for medium-density screens. 44 */ 45 public static final int DENSITY_MEDIUM = 160; 46 47 /** 48 * Intermediate density for screens that sit between {@link #DENSITY_MEDIUM} (160dpi) and 49 * {@link #DENSITY_HIGH} (240dpi). This is not a density that applications should target, 50 * instead relying on the system to scale their {@link #DENSITY_HIGH} assets for them. 51 */ 52 public static final int DENSITY_180 = 180; 53 54 /** 55 * Intermediate density for screens that sit between {@link #DENSITY_MEDIUM} (160dpi) and 56 * {@link #DENSITY_HIGH} (240dpi). This is not a density that applications should target, 57 * instead relying on the system to scale their {@link #DENSITY_HIGH} assets for them. 58 */ 59 public static final int DENSITY_200 = 200; 60 61 /** 62 * This is a secondary density, added for some common screen configurations. 63 * It is recommended that applications not generally target this as a first 64 * class density -- that is, don't supply specific graphics for this 65 * density, instead allow the platform to scale from other densities 66 * (typically {@link #DENSITY_HIGH}) as 67 * appropriate. In most cases (such as using bitmaps in 68 * {@link android.graphics.drawable.Drawable}) the platform 69 * can perform this scaling at load time, so the only cost is some slight 70 * startup runtime overhead. 71 * 72 * <p>This density was original introduced to correspond with a 73 * 720p TV screen: the density for 1080p televisions is 74 * {@link #DENSITY_XHIGH}, and the value here provides the same UI 75 * size for a TV running at 720p. It has also found use in 7" tablets, 76 * when these devices have 1280x720 displays. 77 */ 78 public static final int DENSITY_TV = 213; 79 80 /** 81 * Intermediate density for screens that sit between {@link #DENSITY_MEDIUM} (160dpi) and 82 * {@link #DENSITY_HIGH} (240dpi). This is not a density that applications should target, 83 * instead relying on the system to scale their {@link #DENSITY_HIGH} assets for them. 84 */ 85 public static final int DENSITY_220 = 220; 86 87 /** 88 * Standard quantized DPI for high-density screens. 89 */ 90 public static final int DENSITY_HIGH = 240; 91 92 /** 93 * Intermediate density for screens that sit between {@link #DENSITY_HIGH} (240dpi) and 94 * {@link #DENSITY_XHIGH} (320dpi). This is not a density that applications should target, 95 * instead relying on the system to scale their {@link #DENSITY_XHIGH} assets for them. 96 */ 97 public static final int DENSITY_260 = 260; 98 99 /** 100 * Intermediate density for screens that sit between {@link #DENSITY_HIGH} (240dpi) and 101 * {@link #DENSITY_XHIGH} (320dpi). This is not a density that applications should target, 102 * instead relying on the system to scale their {@link #DENSITY_XHIGH} assets for them. 103 */ 104 public static final int DENSITY_280 = 280; 105 106 /** 107 * Intermediate density for screens that sit between {@link #DENSITY_HIGH} (240dpi) and 108 * {@link #DENSITY_XHIGH} (320dpi). This is not a density that applications should target, 109 * instead relying on the system to scale their {@link #DENSITY_XHIGH} assets for them. 110 */ 111 public static final int DENSITY_300 = 300; 112 113 /** 114 * Standard quantized DPI for extra-high-density screens. 115 */ 116 public static final int DENSITY_XHIGH = 320; 117 118 /** 119 * Intermediate density for screens that sit somewhere between 120 * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). 121 * This is not a density that applications should target, instead relying 122 * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. 123 */ 124 public static final int DENSITY_340 = 340; 125 126 /** 127 * Intermediate density for screens that sit somewhere between 128 * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). 129 * This is not a density that applications should target, instead relying 130 * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. 131 */ 132 public static final int DENSITY_360 = 360; 133 134 /** 135 * Intermediate density for screens that sit somewhere between 136 * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). 137 * This is not a density that applications should target, instead relying 138 * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. 139 */ 140 public static final int DENSITY_400 = 400; 141 142 /** 143 * Intermediate density for screens that sit somewhere between 144 * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). 145 * This is not a density that applications should target, instead relying 146 * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. 147 */ 148 public static final int DENSITY_420 = 420; 149 150 /** 151 * Intermediate density for screens that sit somewhere between 152 * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). 153 * This is not a density that applications should target, instead relying 154 * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. 155 */ 156 public static final int DENSITY_440 = 440; 157 158 /** 159 * Intermediate density for screens that sit somewhere between 160 * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). 161 * This is not a density that applications should target, instead relying 162 * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. 163 */ 164 public static final int DENSITY_450 = 450; 165 166 /** 167 * Standard quantized DPI for extra-extra-high-density screens. 168 */ 169 public static final int DENSITY_XXHIGH = 480; 170 171 /** 172 * Intermediate density for screens that sit somewhere between 173 * {@link #DENSITY_XXHIGH} (480 dpi) and {@link #DENSITY_XXXHIGH} (640 dpi). 174 * This is not a density that applications should target, instead relying 175 * on the system to scale their {@link #DENSITY_XXXHIGH} assets for them. 176 */ 177 public static final int DENSITY_560 = 560; 178 179 /** 180 * Intermediate density for screens that sit somewhere between 181 * {@link #DENSITY_XXHIGH} (480 dpi) and {@link #DENSITY_XXXHIGH} (640 dpi). 182 * This is not a density that applications should target, instead relying 183 * on the system to scale their {@link #DENSITY_XXXHIGH} assets for them. 184 */ 185 public static final int DENSITY_600 = 600; 186 187 /** 188 * Standard quantized DPI for extra-extra-extra-high-density screens. Applications 189 * should not generally worry about this density; relying on XHIGH graphics 190 * being scaled up to it should be sufficient for almost all cases. A typical 191 * use of this density would be 4K television screens -- 3840x2160, which 192 * is 2x a traditional HD 1920x1080 screen which runs at DENSITY_XHIGH. 193 */ 194 public static final int DENSITY_XXXHIGH = 640; 195 196 /** 197 * The reference density used throughout the system. 198 */ 199 public static final int DENSITY_DEFAULT = DENSITY_MEDIUM; 200 201 /** 202 * Scaling factor to convert a density in DPI units to the density scale. 203 * @hide 204 */ 205 public static final float DENSITY_DEFAULT_SCALE = 1.0f / DENSITY_DEFAULT; 206 207 /** 208 * The device's current density. 209 * <p> 210 * This value reflects any changes made to the device density. To obtain 211 * the device's stable density, use {@link #DENSITY_DEVICE_STABLE}. 212 * 213 * @hide This value should not be used. 214 * @deprecated Use {@link #DENSITY_DEVICE_STABLE} to obtain the stable 215 * device density or {@link #densityDpi} to obtain the current 216 * density for a specific display. 217 */ 218 @Deprecated 219 @UnsupportedAppUsage 220 public static int DENSITY_DEVICE = getDeviceDensity(); 221 222 /** 223 * The device's stable density. 224 * <p> 225 * This value is constant at run time and may not reflect the current 226 * display density. To obtain the current density for a specific display, 227 * use {@link #densityDpi}. 228 */ 229 public static final int DENSITY_DEVICE_STABLE = getDeviceDensity(); 230 231 /** 232 * The absolute width of the available display size in pixels. 233 */ 234 public int widthPixels; 235 /** 236 * The absolute height of the available display size in pixels. 237 */ 238 public int heightPixels; 239 /** 240 * The logical density of the display. This is a scaling factor for the 241 * Density Independent Pixel unit, where one DIP is one pixel on an 242 * approximately 160 dpi screen (for example a 240x320, 1.5"x2" screen), 243 * providing the baseline of the system's display. Thus on a 160dpi screen 244 * this density value will be 1; on a 120 dpi screen it would be .75; etc. 245 * 246 * <p>This value does not exactly follow the real screen size (as given by 247 * {@link #xdpi} and {@link #ydpi}), but rather is used to scale the size of 248 * the overall UI in steps based on gross changes in the display dpi. For 249 * example, a 240x320 screen will have a density of 1 even if its width is 250 * 1.8", 1.3", etc. However, if the screen resolution is increased to 251 * 320x480 but the screen size remained 1.5"x2" then the density would be 252 * increased (probably to 1.5). 253 * 254 * @see #DENSITY_DEFAULT 255 */ 256 public float density; 257 /** 258 * The screen density expressed as dots-per-inch. May be either 259 * {@link #DENSITY_LOW}, {@link #DENSITY_MEDIUM}, or {@link #DENSITY_HIGH}. 260 */ 261 public int densityDpi; 262 /** 263 * A scaling factor for fonts displayed on the display. This is the same 264 * as {@link #density}, except that it may be adjusted in smaller 265 * increments at runtime based on a user preference for the font size. 266 */ 267 public float scaledDensity; 268 /** 269 * The exact physical pixels per inch of the screen in the X dimension. 270 */ 271 public float xdpi; 272 /** 273 * The exact physical pixels per inch of the screen in the Y dimension. 274 */ 275 public float ydpi; 276 277 /** 278 * The reported display width prior to any compatibility mode scaling 279 * being applied. 280 * @hide 281 */ 282 @UnsupportedAppUsage 283 public int noncompatWidthPixels; 284 /** 285 * The reported display height prior to any compatibility mode scaling 286 * being applied. 287 * @hide 288 */ 289 @UnsupportedAppUsage 290 public int noncompatHeightPixels; 291 /** 292 * The reported display density prior to any compatibility mode scaling 293 * being applied. 294 * @hide 295 */ 296 public float noncompatDensity; 297 /** 298 * The reported display density prior to any compatibility mode scaling 299 * being applied. 300 * @hide 301 */ 302 @UnsupportedAppUsage 303 public int noncompatDensityDpi; 304 /** 305 * The reported scaled density prior to any compatibility mode scaling 306 * being applied. 307 * @hide 308 */ 309 public float noncompatScaledDensity; 310 /** 311 * The reported display xdpi prior to any compatibility mode scaling 312 * being applied. 313 * @hide 314 */ 315 public float noncompatXdpi; 316 /** 317 * The reported display ydpi prior to any compatibility mode scaling 318 * being applied. 319 * @hide 320 */ 321 public float noncompatYdpi; 322 DisplayMetrics()323 public DisplayMetrics() { 324 } 325 setTo(DisplayMetrics o)326 public void setTo(DisplayMetrics o) { 327 if (this == o) { 328 return; 329 } 330 331 widthPixels = o.widthPixels; 332 heightPixels = o.heightPixels; 333 density = o.density; 334 densityDpi = o.densityDpi; 335 scaledDensity = o.scaledDensity; 336 xdpi = o.xdpi; 337 ydpi = o.ydpi; 338 noncompatWidthPixels = o.noncompatWidthPixels; 339 noncompatHeightPixels = o.noncompatHeightPixels; 340 noncompatDensity = o.noncompatDensity; 341 noncompatDensityDpi = o.noncompatDensityDpi; 342 noncompatScaledDensity = o.noncompatScaledDensity; 343 noncompatXdpi = o.noncompatXdpi; 344 noncompatYdpi = o.noncompatYdpi; 345 } 346 setToDefaults()347 public void setToDefaults() { 348 widthPixels = 0; 349 heightPixels = 0; 350 density = DENSITY_DEVICE / (float) DENSITY_DEFAULT; 351 densityDpi = DENSITY_DEVICE; 352 scaledDensity = density; 353 xdpi = DENSITY_DEVICE; 354 ydpi = DENSITY_DEVICE; 355 noncompatWidthPixels = widthPixels; 356 noncompatHeightPixels = heightPixels; 357 noncompatDensity = density; 358 noncompatDensityDpi = densityDpi; 359 noncompatScaledDensity = scaledDensity; 360 noncompatXdpi = xdpi; 361 noncompatYdpi = ydpi; 362 } 363 364 @Override equals(@ullable Object o)365 public boolean equals(@Nullable Object o) { 366 return o instanceof DisplayMetrics && equals((DisplayMetrics)o); 367 } 368 369 /** 370 * Returns true if these display metrics equal the other display metrics. 371 * 372 * @param other The display metrics with which to compare. 373 * @return True if the display metrics are equal. 374 */ equals(DisplayMetrics other)375 public boolean equals(DisplayMetrics other) { 376 return equalsPhysical(other) 377 && scaledDensity == other.scaledDensity 378 && noncompatScaledDensity == other.noncompatScaledDensity; 379 } 380 381 /** 382 * Returns true if the physical aspects of the two display metrics 383 * are equal. This ignores the scaled density, which is a logical 384 * attribute based on the current desired font size. 385 * 386 * @param other The display metrics with which to compare. 387 * @return True if the display metrics are equal. 388 * @hide 389 */ equalsPhysical(DisplayMetrics other)390 public boolean equalsPhysical(DisplayMetrics other) { 391 return other != null 392 && widthPixels == other.widthPixels 393 && heightPixels == other.heightPixels 394 && density == other.density 395 && densityDpi == other.densityDpi 396 && xdpi == other.xdpi 397 && ydpi == other.ydpi 398 && noncompatWidthPixels == other.noncompatWidthPixels 399 && noncompatHeightPixels == other.noncompatHeightPixels 400 && noncompatDensity == other.noncompatDensity 401 && noncompatDensityDpi == other.noncompatDensityDpi 402 && noncompatXdpi == other.noncompatXdpi 403 && noncompatYdpi == other.noncompatYdpi; 404 } 405 406 @Override hashCode()407 public int hashCode() { 408 return widthPixels * heightPixels * densityDpi; 409 } 410 411 @Override toString()412 public String toString() { 413 return "DisplayMetrics{density=" + density + ", width=" + widthPixels + 414 ", height=" + heightPixels + ", scaledDensity=" + scaledDensity + 415 ", xdpi=" + xdpi + ", ydpi=" + ydpi + "}"; 416 } 417 getDeviceDensity()418 private static int getDeviceDensity() { 419 // qemu.sf.lcd_density can be used to override ro.sf.lcd_density 420 // when running in the emulator, allowing for dynamic configurations. 421 // The reason for this is that ro.sf.lcd_density is write-once and is 422 // set by the init process when it parses build.prop before anything else. 423 return SystemProperties.getInt("qemu.sf.lcd_density", 424 SystemProperties.getInt("ro.sf.lcd_density", DENSITY_DEFAULT)); 425 } 426 } 427