TypedValue.java revision 9066cfe9886ac131c34d59ed0e2d287b0e3c0087
1/*
2 * Copyright (C) 2007 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
17package android.util;
18
19/**
20 * Container for a dynamically typed data value.  Primarily used with
21 * {@link android.content.res.Resources} for holding resource values.
22 */
23public class TypedValue {
24    /** The value contains no data. */
25    public static final int TYPE_NULL = 0x00;
26
27    /** The <var>data</var> field holds a resource identifier. */
28    public static final int TYPE_REFERENCE = 0x01;
29    /** The <var>data</var> field holds an attribute resource
30     *  identifier (referencing an attribute in the current theme
31     *  style, not a resource entry). */
32    public static final int TYPE_ATTRIBUTE = 0x02;
33    /** The <var>string</var> field holds string data.  In addition, if
34     *  <var>data</var> is non-zero then it is the string block
35     *  index of the string and <var>assetCookie</var> is the set of
36     *  assets the string came from. */
37    public static final int TYPE_STRING = 0x03;
38    /** The <var>data</var> field holds an IEEE 754 floating point number. */
39    public static final int TYPE_FLOAT = 0x04;
40    /** The <var>data</var> field holds a complex number encoding a
41     *  dimension value. */
42    public static final int TYPE_DIMENSION = 0x05;
43    /** The <var>data</var> field holds a complex number encoding a fraction
44     *  of a container. */
45    public static final int TYPE_FRACTION = 0x06;
46
47    /** Identifies the start of plain integer values.  Any type value
48     *  from this to {@link #TYPE_LAST_INT} means the
49     *  <var>data</var> field holds a generic integer value. */
50    public static final int TYPE_FIRST_INT = 0x10;
51
52    /** The <var>data</var> field holds a number that was
53     *  originally specified in decimal. */
54    public static final int TYPE_INT_DEC = 0x10;
55    /** The <var>data</var> field holds a number that was
56     *  originally specified in hexadecimal (0xn). */
57    public static final int TYPE_INT_HEX = 0x11;
58    /** The <var>data</var> field holds 0 or 1 that was originally
59     *  specified as "false" or "true". */
60    public static final int TYPE_INT_BOOLEAN = 0x12;
61
62    /** Identifies the start of integer values that were specified as
63     *  color constants (starting with '#'). */
64    public static final int TYPE_FIRST_COLOR_INT = 0x1c;
65
66    /** The <var>data</var> field holds a color that was originally
67     *  specified as #aarrggbb. */
68    public static final int TYPE_INT_COLOR_ARGB8 = 0x1c;
69    /** The <var>data</var> field holds a color that was originally
70     *  specified as #rrggbb. */
71    public static final int TYPE_INT_COLOR_RGB8 = 0x1d;
72    /** The <var>data</var> field holds a color that was originally
73     *  specified as #argb. */
74    public static final int TYPE_INT_COLOR_ARGB4 = 0x1e;
75    /** The <var>data</var> field holds a color that was originally
76     *  specified as #rgb. */
77    public static final int TYPE_INT_COLOR_RGB4 = 0x1f;
78
79    /** Identifies the end of integer values that were specified as color
80     *  constants. */
81    public static final int TYPE_LAST_COLOR_INT = 0x1f;
82
83    /** Identifies the end of plain integer values. */
84    public static final int TYPE_LAST_INT = 0x1f;
85
86    /* ------------------------------------------------------------ */
87
88    /** Complex data: bit location of unit information. */
89    public static final int COMPLEX_UNIT_SHIFT = 0;
90    /** Complex data: mask to extract unit information (after shifting by
91     *  {@link #COMPLEX_UNIT_SHIFT}). This gives us 16 possible types, as
92     *  defined below. */
93    public static final int COMPLEX_UNIT_MASK = 0xf;
94
95    /** {@link #TYPE_DIMENSION} complex unit: Value is raw pixels. */
96    public static final int COMPLEX_UNIT_PX = 0;
97    /** {@link #TYPE_DIMENSION} complex unit: Value is Device Independent
98     *  Pixels. */
99    public static final int COMPLEX_UNIT_DIP = 1;
100    /** {@link #TYPE_DIMENSION} complex unit: Value is a scaled pixel. */
101    public static final int COMPLEX_UNIT_SP = 2;
102    /** {@link #TYPE_DIMENSION} complex unit: Value is in points. */
103    public static final int COMPLEX_UNIT_PT = 3;
104    /** {@link #TYPE_DIMENSION} complex unit: Value is in inches. */
105    public static final int COMPLEX_UNIT_IN = 4;
106    /** {@link #TYPE_DIMENSION} complex unit: Value is in millimeters. */
107    public static final int COMPLEX_UNIT_MM = 5;
108
109    /** {@link #TYPE_FRACTION} complex unit: A basic fraction of the overall
110     *  size. */
111    public static final int COMPLEX_UNIT_FRACTION = 0;
112    /** {@link #TYPE_FRACTION} complex unit: A fraction of the parent size. */
113    public static final int COMPLEX_UNIT_FRACTION_PARENT = 1;
114
115    /** Complex data: where the radix information is, telling where the decimal
116     *  place appears in the mantissa. */
117    public static final int COMPLEX_RADIX_SHIFT = 4;
118    /** Complex data: mask to extract radix information (after shifting by
119     * {@link #COMPLEX_RADIX_SHIFT}). This give us 4 possible fixed point
120     * representations as defined below. */
121    public static final int COMPLEX_RADIX_MASK = 0x3;
122
123    /** Complex data: the mantissa is an integral number -- i.e., 0xnnnnnn.0 */
124    public static final int COMPLEX_RADIX_23p0 = 0;
125    /** Complex data: the mantissa magnitude is 16 bits -- i.e, 0xnnnn.nn */
126    public static final int COMPLEX_RADIX_16p7 = 1;
127    /** Complex data: the mantissa magnitude is 8 bits -- i.e, 0xnn.nnnn */
128    public static final int COMPLEX_RADIX_8p15 = 2;
129    /** Complex data: the mantissa magnitude is 0 bits -- i.e, 0x0.nnnnnn */
130    public static final int COMPLEX_RADIX_0p23 = 3;
131
132    /** Complex data: bit location of mantissa information. */
133    public static final int COMPLEX_MANTISSA_SHIFT = 8;
134    /** Complex data: mask to extract mantissa information (after shifting by
135     *  {@link #COMPLEX_MANTISSA_SHIFT}). This gives us 23 bits of precision;
136     *  the top bit is the sign. */
137    public static final int COMPLEX_MANTISSA_MASK = 0xffffff;
138
139    /* ------------------------------------------------------------ */
140
141    /**
142     * If {@link #density} is equal to this value, then the density should be
143     * treated as the system's default density value: {@link DisplayMetrics#DEFAULT_DENSITY}.
144     *
145     * @hide Pending API council approval
146     */
147    public static final int DENSITY_DEFAULT = 0;
148
149    /* ------------------------------------------------------------ */
150
151    /** The type held by this value, as defined by the constants here.
152     *  This tells you how to interpret the other fields in the object. */
153    public int type;
154
155    /** If the value holds a string, this is it. */
156    public CharSequence string;
157
158    /** Basic data in the value, interpreted according to {@link #type} */
159    public int data;
160
161    /** Additional information about where the value came from; only
162     *  set for strings. */
163    public int assetCookie;
164
165    /** If Value came from a resource, this holds the corresponding resource id. */
166    public int resourceId;
167
168    /** If Value came from a resource, these are the configurations for which
169     *  its contents can change. */
170    public int changingConfigurations = -1;
171
172    /**
173     * If the Value came from a resource, this holds the corresponding pixel density.
174     *
175     * @hide Pending API council approval
176     * */
177    public int density;
178
179    /* ------------------------------------------------------------ */
180
181    /** Return the data for this value as a float.  Only use for values
182     *  whose type is {@link #TYPE_FLOAT}. */
183    public final float getFloat() {
184        return Float.intBitsToFloat(data);
185    }
186
187    private static final float MANTISSA_MULT =
188        1.0f / (1<<TypedValue.COMPLEX_MANTISSA_SHIFT);
189    private static final float[] RADIX_MULTS = new float[] {
190        1.0f*MANTISSA_MULT, 1.0f/(1<<7)*MANTISSA_MULT,
191        1.0f/(1<<15)*MANTISSA_MULT, 1.0f/(1<<23)*MANTISSA_MULT
192    };
193
194    /**
195     * Retrieve the base value from a complex data integer.  This uses the
196     * {@link #COMPLEX_MANTISSA_MASK} and {@link #COMPLEX_RADIX_MASK} fields of
197     * the data to compute a floating point representation of the number they
198     * describe.  The units are ignored.
199     *
200     * @param complex A complex data value.
201     *
202     * @return A floating point value corresponding to the complex data.
203     */
204    public static float complexToFloat(int complex)
205    {
206        return (complex&(TypedValue.COMPLEX_MANTISSA_MASK
207                   <<TypedValue.COMPLEX_MANTISSA_SHIFT))
208            * RADIX_MULTS[(complex>>TypedValue.COMPLEX_RADIX_SHIFT)
209                            & TypedValue.COMPLEX_RADIX_MASK];
210    }
211
212    /**
213     * Converts a complex data value holding a dimension to its final floating
214     * point value. The given <var>data</var> must be structured as a
215     * {@link #TYPE_DIMENSION}.
216     *
217     * @param data A complex data value holding a unit, magnitude, and
218     *             mantissa.
219     * @param metrics Current display metrics to use in the conversion --
220     *                supplies display density and scaling information.
221     *
222     * @return The complex floating point value multiplied by the appropriate
223     * metrics depending on its unit.
224     */
225    public static float complexToDimension(int data, DisplayMetrics metrics)
226    {
227        return applyDimension(
228            (data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK,
229            complexToFloat(data),
230            metrics);
231    }
232
233    /**
234     * Converts a complex data value holding a dimension to its final value
235     * as an integer pixel offset.  This is the same as
236     * {@link #complexToDimension}, except the raw floating point value is
237     * truncated to an integer (pixel) value.
238     * The given <var>data</var> must be structured as a
239     * {@link #TYPE_DIMENSION}.
240     *
241     * @param data A complex data value holding a unit, magnitude, and
242     *             mantissa.
243     * @param metrics Current display metrics to use in the conversion --
244     *                supplies display density and scaling information.
245     *
246     * @return The number of pixels specified by the data and its desired
247     * multiplier and units.
248     */
249    public static int complexToDimensionPixelOffset(int data,
250            DisplayMetrics metrics)
251    {
252        return (int)applyDimension(
253                (data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK,
254                complexToFloat(data),
255                metrics);
256    }
257
258    /**
259     * Converts a complex data value holding a dimension to its final value
260     * as an integer pixel size.  This is the same as
261     * {@link #complexToDimension}, except the raw floating point value is
262     * converted to an integer (pixel) value for use as a size.  A size
263     * conversion involves rounding the base value, and ensuring that a
264     * non-zero base value is at least one pixel in size.
265     * The given <var>data</var> must be structured as a
266     * {@link #TYPE_DIMENSION}.
267     *
268     * @param data A complex data value holding a unit, magnitude, and
269     *             mantissa.
270     * @param metrics Current display metrics to use in the conversion --
271     *                supplies display density and scaling information.
272     *
273     * @return The number of pixels specified by the data and its desired
274     * multiplier and units.
275     */
276    public static int complexToDimensionPixelSize(int data,
277            DisplayMetrics metrics)
278    {
279        final float value = complexToFloat(data);
280        final float f = applyDimension(
281                (data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK,
282                value,
283                metrics);
284        final int res = (int)(f+0.5f);
285        if (res != 0) return res;
286        if (value == 0) return 0;
287        if (value > 0) return 1;
288        return -1;
289    }
290
291    public static float complexToDimensionNoisy(int data, DisplayMetrics metrics)
292    {
293        float res = complexToDimension(data, metrics);
294        System.out.println(
295            "Dimension (0x" + ((data>>TypedValue.COMPLEX_MANTISSA_SHIFT)
296                               & TypedValue.COMPLEX_MANTISSA_MASK)
297            + "*" + (RADIX_MULTS[(data>>TypedValue.COMPLEX_RADIX_SHIFT)
298                                & TypedValue.COMPLEX_RADIX_MASK] / MANTISSA_MULT)
299            + ")" + DIMENSION_UNIT_STRS[(data>>COMPLEX_UNIT_SHIFT)
300                                & COMPLEX_UNIT_MASK]
301            + " = " + res);
302        return res;
303    }
304
305    /**
306     * Converts an unpacked complex data value holding a dimension to its final floating
307     * point value. The two parameters <var>unit</var> and <var>value</var>
308     * are as in {@link #TYPE_DIMENSION}.
309     *
310     * @param unit The unit to convert from.
311     * @param value The value to apply the unit to.
312     * @param metrics Current display metrics to use in the conversion --
313     *                supplies display density and scaling information.
314     *
315     * @return The complex floating point value multiplied by the appropriate
316     * metrics depending on its unit.
317     */
318    public static float applyDimension(int unit, float value,
319                                       DisplayMetrics metrics)
320    {
321        switch (unit) {
322        case COMPLEX_UNIT_PX:
323            return value;
324        case COMPLEX_UNIT_DIP:
325            return value * metrics.density;
326        case COMPLEX_UNIT_SP:
327            return value * metrics.scaledDensity;
328        case COMPLEX_UNIT_PT:
329            return value * metrics.xdpi * (1.0f/72);
330        case COMPLEX_UNIT_IN:
331            return value * metrics.xdpi;
332        case COMPLEX_UNIT_MM:
333            return value * metrics.xdpi * (1.0f/25.4f);
334        }
335        return 0;
336    }
337
338    /**
339     * Return the data for this value as a dimension.  Only use for values
340     * whose type is {@link #TYPE_DIMENSION}.
341     *
342     * @param metrics Current display metrics to use in the conversion --
343     *                supplies display density and scaling information.
344     *
345     * @return The complex floating point value multiplied by the appropriate
346     * metrics depending on its unit.
347     */
348    public float getDimension(DisplayMetrics metrics)
349    {
350        return complexToDimension(data, metrics);
351    }
352
353    /**
354     * Converts a complex data value holding a fraction to its final floating
355     * point value. The given <var>data</var> must be structured as a
356     * {@link #TYPE_FRACTION}.
357     *
358     * @param data A complex data value holding a unit, magnitude, and
359     *             mantissa.
360     * @param base The base value of this fraction.  In other words, a
361     *             standard fraction is multiplied by this value.
362     * @param pbase The parent base value of this fraction.  In other
363     *             words, a parent fraction (nn%p) is multiplied by this
364     *             value.
365     *
366     * @return The complex floating point value multiplied by the appropriate
367     * base value depending on its unit.
368     */
369    public static float complexToFraction(int data, float base, float pbase)
370    {
371        switch ((data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK) {
372        case COMPLEX_UNIT_FRACTION:
373            return complexToFloat(data) * base;
374        case COMPLEX_UNIT_FRACTION_PARENT:
375            return complexToFloat(data) * pbase;
376        }
377        return 0;
378    }
379
380    /**
381     * Return the data for this value as a fraction.  Only use for values whose
382     * type is {@link #TYPE_FRACTION}.
383     *
384     * @param base The base value of this fraction.  In other words, a
385     *             standard fraction is multiplied by this value.
386     * @param pbase The parent base value of this fraction.  In other
387     *             words, a parent fraction (nn%p) is multiplied by this
388     *             value.
389     *
390     * @return The complex floating point value multiplied by the appropriate
391     * base value depending on its unit.
392     */
393    public float getFraction(float base, float pbase)
394    {
395        return complexToFraction(data, base, pbase);
396    }
397
398    /**
399     * Regardless of the actual type of the value, try to convert it to a
400     * string value.  For example, a color type will be converted to a
401     * string of the form #aarrggbb.
402     *
403     * @return CharSequence The coerced string value.  If the value is
404     *         null or the type is not known, null is returned.
405     */
406    public final CharSequence coerceToString()
407    {
408        int t = type;
409        if (t == TYPE_STRING) {
410            return string;
411        }
412        return coerceToString(t, data);
413    }
414
415    private static final String[] DIMENSION_UNIT_STRS = new String[] {
416        "px", "dip", "sp", "pt", "in", "mm"
417    };
418    private static final String[] FRACTION_UNIT_STRS = new String[] {
419        "%", "%p"
420    };
421
422    /**
423     * Perform type conversion as per {@link #coerceToString()} on an
424     * explicitly supplied type and data.
425     *
426     * @param type The data type identifier.
427     * @param data The data value.
428     *
429     * @return String The coerced string value.  If the value is
430     *         null or the type is not known, null is returned.
431     */
432    public static final String coerceToString(int type, int data)
433    {
434        switch (type) {
435        case TYPE_NULL:
436            return null;
437        case TYPE_REFERENCE:
438            return "@" + data;
439        case TYPE_ATTRIBUTE:
440            return "?" + data;
441        case TYPE_FLOAT:
442            return Float.toString(Float.intBitsToFloat(data));
443        case TYPE_DIMENSION:
444            return Float.toString(complexToFloat(data)) + DIMENSION_UNIT_STRS[
445                (data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK];
446        case TYPE_FRACTION:
447            return Float.toString(complexToFloat(data)*100) + FRACTION_UNIT_STRS[
448                (data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK];
449        case TYPE_INT_HEX:
450            return "0x" + Integer.toHexString(data);
451        case TYPE_INT_BOOLEAN:
452            return data != 0 ? "true" : "false";
453        }
454
455        if (type >= TYPE_FIRST_COLOR_INT && type <= TYPE_LAST_COLOR_INT) {
456            return "#" + Integer.toHexString(data);
457        } else if (type >= TYPE_FIRST_INT && type <= TYPE_LAST_INT) {
458            return Integer.toString(data);
459        }
460
461        return null;
462    }
463
464    public void setTo(TypedValue other)
465    {
466        type = other.type;
467        string = other.string;
468        data = other.data;
469        assetCookie = other.assetCookie;
470        resourceId = other.resourceId;
471        density = other.density;
472    }
473
474    public String toString()
475    {
476        StringBuilder sb = new StringBuilder();
477        sb.append("TypedValue{t=0x").append(Integer.toHexString(type));
478        sb.append("/d=0x").append(Integer.toHexString(data));
479        if (type == TYPE_STRING) {
480            sb.append(" \"").append(string != null ? string : "<null>").append("\"");
481        }
482        if (assetCookie != 0) {
483            sb.append(" a=").append(assetCookie);
484        }
485        if (resourceId != 0) {
486            sb.append(" r=0x").append(Integer.toHexString(resourceId));
487        }
488        sb.append("}");
489        return sb.toString();
490    }
491};
492
493