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.content.res.FontScaleConverter; 22 import android.os.SystemProperties; 23 import android.view.WindowManager; 24 25 /** 26 * A structure describing general information about a display, such as its 27 * size, density, and font scaling. 28 * <p>To access the DisplayMetrics members, retrieve display metrics like this:</p> 29 * <pre>context.getResources().getDisplayMetrics();</pre> 30 * 31 * <p> 32 * For UI layout, obtain {@link android.view.WindowMetrics} from 33 * {@link WindowManager#getCurrentWindowMetrics()}. {@code DisplayMetrics} should only be used for 34 * obtaining display related properties, such as {@link #xdpi} and {@link #ydpi} 35 * </p><p> 36 * See {@link #density} for more information about the differences between {@link #xdpi}, 37 * {@link #ydpi} and {@link #density}. 38 * </p> 39 * 40 */ 41 public class DisplayMetrics { 42 /** 43 * Standard quantized DPI for low-density screens. 44 */ 45 public static final int DENSITY_LOW = 120; 46 47 /** 48 * Intermediate density for screens that sit between {@link #DENSITY_LOW} (120dpi) and 49 * {@link #DENSITY_MEDIUM} (160dpi). This is not a density that applications should target, 50 * instead relying on the system to scale their {@link #DENSITY_MEDIUM} assets for them. 51 */ 52 public static final int DENSITY_140 = 140; 53 54 /** 55 * Standard quantized DPI for medium-density screens. 56 */ 57 public static final int DENSITY_MEDIUM = 160; 58 59 /** 60 * Intermediate density for screens that sit between {@link #DENSITY_MEDIUM} (160dpi) and 61 * {@link #DENSITY_HIGH} (240dpi). This is not a density that applications should target, 62 * instead relying on the system to scale their {@link #DENSITY_HIGH} assets for them. 63 */ 64 public static final int DENSITY_180 = 180; 65 66 /** 67 * Intermediate density for screens that sit between {@link #DENSITY_MEDIUM} (160dpi) and 68 * {@link #DENSITY_HIGH} (240dpi). This is not a density that applications should target, 69 * instead relying on the system to scale their {@link #DENSITY_HIGH} assets for them. 70 */ 71 public static final int DENSITY_200 = 200; 72 73 /** 74 * This is a secondary density, added for some common screen configurations. 75 * It is recommended that applications not generally target this as a first 76 * class density -- that is, don't supply specific graphics for this 77 * density, instead allow the platform to scale from other densities 78 * (typically {@link #DENSITY_HIGH}) as 79 * appropriate. In most cases (such as using bitmaps in 80 * {@link android.graphics.drawable.Drawable}) the platform 81 * can perform this scaling at load time, so the only cost is some slight 82 * startup runtime overhead. 83 * 84 * <p>This density was original introduced to correspond with a 85 * 720p TV screen: the density for 1080p televisions is 86 * {@link #DENSITY_XHIGH}, and the value here provides the same UI 87 * size for a TV running at 720p. It has also found use in 7" tablets, 88 * when these devices have 1280x720 displays. 89 */ 90 public static final int DENSITY_TV = 213; 91 92 /** 93 * Intermediate density for screens that sit between {@link #DENSITY_MEDIUM} (160dpi) and 94 * {@link #DENSITY_HIGH} (240dpi). This is not a density that applications should target, 95 * instead relying on the system to scale their {@link #DENSITY_HIGH} assets for them. 96 */ 97 public static final int DENSITY_220 = 220; 98 99 /** 100 * Standard quantized DPI for high-density screens. 101 */ 102 public static final int DENSITY_HIGH = 240; 103 104 /** 105 * Intermediate density for screens that sit between {@link #DENSITY_HIGH} (240dpi) and 106 * {@link #DENSITY_XHIGH} (320dpi). This is not a density that applications should target, 107 * instead relying on the system to scale their {@link #DENSITY_XHIGH} assets for them. 108 */ 109 public static final int DENSITY_260 = 260; 110 111 /** 112 * Intermediate density for screens that sit between {@link #DENSITY_HIGH} (240dpi) and 113 * {@link #DENSITY_XHIGH} (320dpi). This is not a density that applications should target, 114 * instead relying on the system to scale their {@link #DENSITY_XHIGH} assets for them. 115 */ 116 public static final int DENSITY_280 = 280; 117 118 /** 119 * Intermediate density for screens that sit between {@link #DENSITY_HIGH} (240dpi) and 120 * {@link #DENSITY_XHIGH} (320dpi). This is not a density that applications should target, 121 * instead relying on the system to scale their {@link #DENSITY_XHIGH} assets for them. 122 */ 123 public static final int DENSITY_300 = 300; 124 125 /** 126 * Standard quantized DPI for extra-high-density screens. 127 */ 128 public static final int DENSITY_XHIGH = 320; 129 130 /** 131 * Intermediate density for screens that sit somewhere between 132 * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). 133 * This is not a density that applications should target, instead relying 134 * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. 135 */ 136 public static final int DENSITY_340 = 340; 137 138 /** 139 * Intermediate density for screens that sit somewhere between 140 * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). 141 * This is not a density that applications should target, instead relying 142 * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. 143 */ 144 public static final int DENSITY_360 = 360; 145 146 /** 147 * Intermediate density for screens that sit somewhere between 148 * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). 149 * This is not a density that applications should target, instead relying 150 * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. 151 */ 152 public static final int DENSITY_400 = 400; 153 154 /** 155 * Intermediate density for screens that sit somewhere between 156 * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). 157 * This is not a density that applications should target, instead relying 158 * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. 159 */ 160 public static final int DENSITY_420 = 420; 161 162 /** 163 * Intermediate density for screens that sit somewhere between 164 * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). 165 * This is not a density that applications should target, instead relying 166 * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. 167 */ 168 public static final int DENSITY_440 = 440; 169 170 /** 171 * Intermediate density for screens that sit somewhere between 172 * {@link #DENSITY_XHIGH} (320 dpi) and {@link #DENSITY_XXHIGH} (480 dpi). 173 * This is not a density that applications should target, instead relying 174 * on the system to scale their {@link #DENSITY_XXHIGH} assets for them. 175 */ 176 public static final int DENSITY_450 = 450; 177 178 /** 179 * Standard quantized DPI for extra-extra-high-density screens. 180 */ 181 public static final int DENSITY_XXHIGH = 480; 182 183 /** 184 * Intermediate density for screens that sit somewhere between 185 * {@link #DENSITY_XXHIGH} (480 dpi) and {@link #DENSITY_XXXHIGH} (640 dpi). 186 * This is not a density that applications should target, instead relying 187 * on the system to scale their {@link #DENSITY_XXXHIGH} assets for them. 188 */ 189 public static final int DENSITY_520 = 520; 190 191 /** 192 * Intermediate density for screens that sit somewhere between 193 * {@link #DENSITY_XXHIGH} (480 dpi) and {@link #DENSITY_XXXHIGH} (640 dpi). 194 * This is not a density that applications should target, instead relying 195 * on the system to scale their {@link #DENSITY_XXXHIGH} assets for them. 196 */ 197 public static final int DENSITY_560 = 560; 198 199 /** 200 * Intermediate density for screens that sit somewhere between 201 * {@link #DENSITY_XXHIGH} (480 dpi) and {@link #DENSITY_XXXHIGH} (640 dpi). 202 * This is not a density that applications should target, instead relying 203 * on the system to scale their {@link #DENSITY_XXXHIGH} assets for them. 204 */ 205 public static final int DENSITY_600 = 600; 206 207 /** 208 * Standard quantized DPI for extra-extra-extra-high-density screens. Applications 209 * should not generally worry about this density; relying on XHIGH graphics 210 * being scaled up to it should be sufficient for almost all cases. A typical 211 * use of this density would be 4K television screens -- 3840x2160, which 212 * is 2x a traditional HD 1920x1080 screen which runs at DENSITY_XHIGH. 213 */ 214 public static final int DENSITY_XXXHIGH = 640; 215 216 /** 217 * The reference density used throughout the system. 218 */ 219 public static final int DENSITY_DEFAULT = DENSITY_MEDIUM; 220 221 /** 222 * Scaling factor to convert a density in DPI units to the density scale. 223 * @hide 224 */ 225 public static final float DENSITY_DEFAULT_SCALE = 1.0f / DENSITY_DEFAULT; 226 227 /** 228 * The device's current density. 229 * <p> 230 * This value reflects any changes made to the device density. To obtain 231 * the device's stable density, use {@link #DENSITY_DEVICE_STABLE}. 232 * 233 * @hide This value should not be used. 234 * @deprecated Use {@link #DENSITY_DEVICE_STABLE} to obtain the stable 235 * device density or {@link #densityDpi} to obtain the current 236 * density for a specific display. 237 */ 238 @Deprecated 239 @UnsupportedAppUsage 240 public static int DENSITY_DEVICE = getDeviceDensity(); 241 242 /** 243 * The device's stable density. 244 * <p> 245 * This value is constant at run time and may not reflect the current 246 * display density. To obtain the current density for a specific display, 247 * use {@link #densityDpi}. 248 */ 249 public static final int DENSITY_DEVICE_STABLE = getDeviceDensity(); 250 251 /** 252 * The absolute width of the available display size in pixels. 253 */ 254 public int widthPixels; 255 /** 256 * The absolute height of the available display size in pixels. 257 */ 258 public int heightPixels; 259 /** 260 * The logical density of the display. This is a scaling factor for the 261 * Density Independent Pixel unit, where one DIP is one pixel on an 262 * approximately 160 dpi screen (for example a 240x320, 1.5"x2" screen), 263 * providing the baseline of the system's display. Thus on a 160dpi screen 264 * this density value will be 1; on a 120 dpi screen it would be .75; etc. 265 * 266 * <p>This value does not exactly follow the real screen size (as given by 267 * {@link #xdpi} and {@link #ydpi}), but rather is used to scale the size of 268 * the overall UI in steps based on gross changes in the display dpi. For 269 * example, a 240x320 screen will have a density of 1 even if its width is 270 * 1.8", 1.3", etc. However, if the screen resolution is increased to 271 * 320x480 but the screen size remained 1.5"x2" then the density would be 272 * increased (probably to 1.5). 273 * 274 * @see #DENSITY_DEFAULT 275 */ 276 public float density; 277 /** 278 * The screen density expressed as dots-per-inch. May be either 279 * {@link #DENSITY_LOW}, {@link #DENSITY_MEDIUM}, or {@link #DENSITY_HIGH}. 280 */ 281 public int densityDpi; 282 /** 283 * A scaling factor for fonts displayed on the display. This is the same 284 * as {@link #density}, except that it may be adjusted in smaller 285 * increments at runtime based on a user preference for the font size. 286 * 287 * @deprecated this scalar factor is no longer accurate due to adaptive non-linear font scaling. 288 * Please use {@link TypedValue#applyDimension(int, float, DisplayMetrics)} or 289 * {@link TypedValue#deriveDimension(int, float, DisplayMetrics)} to convert between SP font 290 * sizes and pixels. 291 */ 292 @Deprecated 293 public float scaledDensity; 294 295 /** 296 * If non-null, this will be used to calculate font sizes instead of {@link #scaledDensity}. 297 * 298 * @hide 299 */ 300 @Nullable 301 public FontScaleConverter fontScaleConverter; 302 303 /** 304 * The exact physical pixels per inch of the screen in the X dimension. 305 */ 306 public float xdpi; 307 /** 308 * The exact physical pixels per inch of the screen in the Y dimension. 309 */ 310 public float ydpi; 311 312 /** 313 * The reported display width prior to any compatibility mode scaling 314 * being applied. 315 * @hide 316 */ 317 @UnsupportedAppUsage 318 public int noncompatWidthPixels; 319 /** 320 * The reported display height prior to any compatibility mode scaling 321 * being applied. 322 * @hide 323 */ 324 @UnsupportedAppUsage 325 public int noncompatHeightPixels; 326 /** 327 * The reported display density prior to any compatibility mode scaling 328 * being applied. 329 * @hide 330 */ 331 public float noncompatDensity; 332 /** 333 * The reported display density prior to any compatibility mode scaling 334 * being applied. 335 * @hide 336 */ 337 @UnsupportedAppUsage 338 public int noncompatDensityDpi; 339 /** 340 * The reported scaled density prior to any compatibility mode scaling 341 * being applied. 342 * @hide 343 */ 344 public float noncompatScaledDensity; 345 /** 346 * The reported display xdpi prior to any compatibility mode scaling 347 * being applied. 348 * @hide 349 */ 350 public float noncompatXdpi; 351 /** 352 * The reported display ydpi prior to any compatibility mode scaling 353 * being applied. 354 * @hide 355 */ 356 public float noncompatYdpi; 357 DisplayMetrics()358 public DisplayMetrics() { 359 } 360 setTo(DisplayMetrics o)361 public void setTo(DisplayMetrics o) { 362 if (this == o) { 363 return; 364 } 365 366 widthPixels = o.widthPixels; 367 heightPixels = o.heightPixels; 368 density = o.density; 369 densityDpi = o.densityDpi; 370 scaledDensity = o.scaledDensity; 371 xdpi = o.xdpi; 372 ydpi = o.ydpi; 373 noncompatWidthPixels = o.noncompatWidthPixels; 374 noncompatHeightPixels = o.noncompatHeightPixels; 375 noncompatDensity = o.noncompatDensity; 376 noncompatDensityDpi = o.noncompatDensityDpi; 377 noncompatScaledDensity = o.noncompatScaledDensity; 378 noncompatXdpi = o.noncompatXdpi; 379 noncompatYdpi = o.noncompatYdpi; 380 fontScaleConverter = o.fontScaleConverter; 381 } 382 setToDefaults()383 public void setToDefaults() { 384 widthPixels = 0; 385 heightPixels = 0; 386 density = DENSITY_DEVICE / (float) DENSITY_DEFAULT; 387 densityDpi = DENSITY_DEVICE; 388 scaledDensity = density; 389 xdpi = DENSITY_DEVICE; 390 ydpi = DENSITY_DEVICE; 391 noncompatWidthPixels = widthPixels; 392 noncompatHeightPixels = heightPixels; 393 noncompatDensity = density; 394 noncompatDensityDpi = densityDpi; 395 noncompatScaledDensity = scaledDensity; 396 noncompatXdpi = xdpi; 397 noncompatYdpi = ydpi; 398 fontScaleConverter = null; 399 } 400 401 @Override equals(@ullable Object o)402 public boolean equals(@Nullable Object o) { 403 return o instanceof DisplayMetrics && equals((DisplayMetrics)o); 404 } 405 406 /** 407 * Returns true if these display metrics equal the other display metrics. 408 * 409 * @param other The display metrics with which to compare. 410 * @return True if the display metrics are equal. 411 */ equals(DisplayMetrics other)412 public boolean equals(DisplayMetrics other) { 413 return equalsPhysical(other) 414 && scaledDensity == other.scaledDensity 415 && noncompatScaledDensity == other.noncompatScaledDensity; 416 } 417 418 /** 419 * Returns true if the physical aspects of the two display metrics 420 * are equal. This ignores the scaled density, which is a logical 421 * attribute based on the current desired font size. 422 * 423 * @param other The display metrics with which to compare. 424 * @return True if the display metrics are equal. 425 * @hide 426 */ equalsPhysical(DisplayMetrics other)427 public boolean equalsPhysical(DisplayMetrics other) { 428 return other != null 429 && widthPixels == other.widthPixels 430 && heightPixels == other.heightPixels 431 && density == other.density 432 && densityDpi == other.densityDpi 433 && xdpi == other.xdpi 434 && ydpi == other.ydpi 435 && noncompatWidthPixels == other.noncompatWidthPixels 436 && noncompatHeightPixels == other.noncompatHeightPixels 437 && noncompatDensity == other.noncompatDensity 438 && noncompatDensityDpi == other.noncompatDensityDpi 439 && noncompatXdpi == other.noncompatXdpi 440 && noncompatYdpi == other.noncompatYdpi; 441 } 442 443 @Override hashCode()444 public int hashCode() { 445 return widthPixels * heightPixels * densityDpi; 446 } 447 448 @Override toString()449 public String toString() { 450 return "DisplayMetrics{density=" + density + ", width=" + widthPixels + 451 ", height=" + heightPixels + ", scaledDensity=" + scaledDensity + 452 ", xdpi=" + xdpi + ", ydpi=" + ydpi + "}"; 453 } 454 getDeviceDensity()455 private static int getDeviceDensity() { 456 // qemu.sf.lcd_density can be used to override ro.sf.lcd_density 457 // when running in the emulator, allowing for dynamic configurations. 458 // The reason for this is that ro.sf.lcd_density is write-once and is 459 // set by the init process when it parses build.prop before anything else. 460 return SystemProperties.getInt("qemu.sf.lcd_density", 461 SystemProperties.getInt("ro.sf.lcd_density", DENSITY_DEFAULT)); 462 } 463 } 464