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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* Copyright (C) 2007 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 com.android.internal.R;
/**
* State sets are arrays of positive ints where each element
* represents the state of a {@link android.view.View} (e.g. focused,
* selected, visible, etc.). A {@link android.view.View} may be in
* one or more of those states.
*
* A state spec is an array of signed ints where each element
* represents a required (if positive) or an undesired (if negative)
* {@link android.view.View} state.
*
* Utils dealing with state sets.
*
* In theory we could encapsulate the state set and state spec arrays
* and not have static methods here but there is some concern about
* performance since these methods are called during view drawing.
*/
public class StateSet {
/**
* The order here is very important to
* {@link android.view.View#getDrawableState()}
*/
private static final int[][] VIEW_STATE_SETS;
/** @hide */
public static final int VIEW_STATE_WINDOW_FOCUSED = 1;
/** @hide */
public static final int VIEW_STATE_SELECTED = 1 << 1;
/** @hide */
public static final int VIEW_STATE_FOCUSED = 1 << 2;
/** @hide */
public static final int VIEW_STATE_ENABLED = 1 << 3;
/** @hide */
public static final int VIEW_STATE_PRESSED = 1 << 4;
/** @hide */
public static final int VIEW_STATE_ACTIVATED = 1 << 5;
/** @hide */
public static final int VIEW_STATE_ACCELERATED = 1 << 6;
/** @hide */
public static final int VIEW_STATE_HOVERED = 1 << 7;
/** @hide */
public static final int VIEW_STATE_DRAG_CAN_ACCEPT = 1 << 8;
/** @hide */
public static final int VIEW_STATE_DRAG_HOVERED = 1 << 9;
static final int[] VIEW_STATE_IDS = new int[] {
R.attr.state_window_focused, VIEW_STATE_WINDOW_FOCUSED,
R.attr.state_selected, VIEW_STATE_SELECTED,
R.attr.state_focused, VIEW_STATE_FOCUSED,
R.attr.state_enabled, VIEW_STATE_ENABLED,
R.attr.state_pressed, VIEW_STATE_PRESSED,
R.attr.state_activated, VIEW_STATE_ACTIVATED,
R.attr.state_accelerated, VIEW_STATE_ACCELERATED,
R.attr.state_hovered, VIEW_STATE_HOVERED,
R.attr.state_drag_can_accept, VIEW_STATE_DRAG_CAN_ACCEPT,
R.attr.state_drag_hovered, VIEW_STATE_DRAG_HOVERED
};
static {
if ((VIEW_STATE_IDS.length / 2) != R.styleable.ViewDrawableStates.length) {
throw new IllegalStateException(
"VIEW_STATE_IDs array length does not match ViewDrawableStates style array");
}
final int[] orderedIds = new int[VIEW_STATE_IDS.length];
for (int i = 0; i < R.styleable.ViewDrawableStates.length; i++) {
final int viewState = R.styleable.ViewDrawableStates[i];
for (int j = 0; j < VIEW_STATE_IDS.length; j += 2) {
if (VIEW_STATE_IDS[j] == viewState) {
orderedIds[i * 2] = viewState;
orderedIds[i * 2 + 1] = VIEW_STATE_IDS[j + 1];
}
}
}
final int NUM_BITS = VIEW_STATE_IDS.length / 2;
VIEW_STATE_SETS = new int[1 << NUM_BITS][];
for (int i = 0; i < VIEW_STATE_SETS.length; i++) {
final int numBits = Integer.bitCount(i);
final int[] set = new int[numBits];
int pos = 0;
for (int j = 0; j < orderedIds.length; j += 2) {
if ((i & orderedIds[j + 1]) != 0) {
set[pos++] = orderedIds[j];
}
}
VIEW_STATE_SETS[i] = set;
}
}
/** @hide */
public static int[] get(int mask) {
if (mask >= VIEW_STATE_SETS.length) {
throw new IllegalArgumentException("Invalid state set mask");
}
return VIEW_STATE_SETS[mask];
}
/** @hide */
public StateSet() {}
/**
* A state specification that will be matched by all StateSets.
*/
public static final int[] WILD_CARD = new int[0];
/**
* A state set that does not contain any valid states.
*/
public static final int[] NOTHING = new int[] { 0 };
/**
* Return whether the stateSetOrSpec is matched by all StateSets.
*
* @param stateSetOrSpec a state set or state spec.
*/
public static boolean isWildCard(int[] stateSetOrSpec) {
return stateSetOrSpec.length == 0 || stateSetOrSpec[0] == 0;
}
/**
* Return whether the stateSet matches the desired stateSpec.
*
* @param stateSpec an array of required (if positive) or
* prohibited (if negative) {@link android.view.View} states.
* @param stateSet an array of {@link android.view.View} states
*/
public static boolean stateSetMatches(int[] stateSpec, int[] stateSet) {
if (stateSet == null) {
return (stateSpec == null || isWildCard(stateSpec));
}
int stateSpecSize = stateSpec.length;
int stateSetSize = stateSet.length;
for (int i = 0; i < stateSpecSize; i++) {
int stateSpecState = stateSpec[i];
if (stateSpecState == 0) {
// We've reached the end of the cases to match against.
return true;
}
final boolean mustMatch;
if (stateSpecState > 0) {
mustMatch = true;
} else {
// We use negative values to indicate must-NOT-match states.
mustMatch = false;
stateSpecState = -stateSpecState;
}
boolean found = false;
for (int j = 0; j < stateSetSize; j++) {
final int state = stateSet[j];
if (state == 0) {
// We've reached the end of states to match.
if (mustMatch) {
// We didn't find this must-match state.
return false;
} else {
// Continue checking other must-not-match states.
break;
}
}
if (state == stateSpecState) {
if (mustMatch) {
found = true;
// Continue checking other other must-match states.
break;
} else {
// Any match of a must-not-match state returns false.
return false;
}
}
}
if (mustMatch && !found) {
// We've reached the end of states to match and we didn't
// find a must-match state.
return false;
}
}
return true;
}
/**
* Return whether the state matches the desired stateSpec.
*
* @param stateSpec an array of required (if positive) or
* prohibited (if negative) {@link android.view.View} states.
* @param state a {@link android.view.View} state
*/
public static boolean stateSetMatches(int[] stateSpec, int state) {
int stateSpecSize = stateSpec.length;
for (int i = 0; i < stateSpecSize; i++) {
int stateSpecState = stateSpec[i];
if (stateSpecState == 0) {
// We've reached the end of the cases to match against.
return true;
}
if (stateSpecState > 0) {
if (state != stateSpecState) {
return false;
}
} else {
// We use negative values to indicate must-NOT-match states.
if (state == -stateSpecState) {
// We matched a must-not-match case.
return false;
}
}
}
return true;
}
/**
* Check whether a list of state specs has an attribute specified.
* @param stateSpecs a list of state specs we're checking.
* @param attr an attribute we're looking for.
* @return {@code true} if the attribute is contained in the state specs.
* @hide
*/
public static boolean containsAttribute(int[][] stateSpecs, int attr) {
if (stateSpecs != null) {
for (int[] spec : stateSpecs) {
if (spec == null) {
break;
}
for (int specAttr : spec) {
if (specAttr == attr || -specAttr == attr) {
return true;
}
}
}
}
return false;
}
public static int[] trimStateSet(int[] states, int newSize) {
if (states.length == newSize) {
return states;
}
int[] trimmedStates = new int[newSize];
System.arraycopy(states, 0, trimmedStates, 0, newSize);
return trimmedStates;
}
public static String dump(int[] states) {
StringBuilder sb = new StringBuilder();
int count = states.length;
for (int i = 0; i < count; i++) {
switch (states[i]) {
case R.attr.state_window_focused:
sb.append("W ");
break;
case R.attr.state_pressed:
sb.append("P ");
break;
case R.attr.state_selected:
sb.append("S ");
break;
case R.attr.state_focused:
sb.append("F ");
break;
case R.attr.state_enabled:
sb.append("E ");
break;
case R.attr.state_checked:
sb.append("C ");
break;
case R.attr.state_activated:
sb.append("A ");
break;
}
}
return sb.toString();
}
}