Java tutorial
/* * Copyright (C) 2010 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.widget; import android.animation.ObjectAnimator; import android.annotation.DrawableRes; import android.annotation.NonNull; import android.annotation.Nullable; import android.annotation.StyleRes; import android.annotation.UnsupportedAppUsage; import android.content.Context; import android.content.res.ColorStateList; import android.content.res.Resources; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Insets; import android.graphics.Paint; import android.graphics.PorterDuff; import android.graphics.Rect; import android.graphics.Region.Op; import android.graphics.Typeface; import android.graphics.drawable.Drawable; import android.os.Build.VERSION_CODES; import android.text.Layout; import android.text.StaticLayout; import android.text.TextPaint; import android.text.TextUtils; import android.text.method.AllCapsTransformationMethod; import android.text.method.TransformationMethod2; import android.util.AttributeSet; import android.util.FloatProperty; import android.util.MathUtils; import android.view.Gravity; import android.view.MotionEvent; import android.view.SoundEffectConstants; import android.view.VelocityTracker; import android.view.ViewConfiguration; import android.view.ViewStructure; import android.view.accessibility.AccessibilityEvent; import android.view.accessibility.AccessibilityNodeInfo; import com.android.internal.R; /** * A Switch is a two-state toggle switch widget that can select between two * options. The user may drag the "thumb" back and forth to choose the selected option, * or simply tap to toggle as if it were a checkbox. The {@link #setText(CharSequence) text} * property controls the text displayed in the label for the switch, whereas the * {@link #setTextOff(CharSequence) off} and {@link #setTextOn(CharSequence) on} text * controls the text on the thumb. Similarly, the * {@link #setTextAppearance(android.content.Context, int) textAppearance} and the related * setTypeface() methods control the typeface and style of label text, whereas the * {@link #setSwitchTextAppearance(android.content.Context, int) switchTextAppearance} and * the related setSwitchTypeface() methods control that of the thumb. * * <p>{@link android.support.v7.widget.SwitchCompat} is a version of * the Switch widget which runs on devices back to API 7.</p> * * <p>See the <a href="{@docRoot}guide/topics/ui/controls/togglebutton.html">Toggle Buttons</a> * guide.</p> * * @attr ref android.R.styleable#Switch_textOn * @attr ref android.R.styleable#Switch_textOff * @attr ref android.R.styleable#Switch_switchMinWidth * @attr ref android.R.styleable#Switch_switchPadding * @attr ref android.R.styleable#Switch_switchTextAppearance * @attr ref android.R.styleable#Switch_thumb * @attr ref android.R.styleable#Switch_thumbTextPadding * @attr ref android.R.styleable#Switch_track */ public class Switch extends CompoundButton { private static final int THUMB_ANIMATION_DURATION = 250; private static final int TOUCH_MODE_IDLE = 0; private static final int TOUCH_MODE_DOWN = 1; private static final int TOUCH_MODE_DRAGGING = 2; // Enum for the "typeface" XML parameter. private static final int SANS = 1; private static final int SERIF = 2; private static final int MONOSPACE = 3; @UnsupportedAppUsage private Drawable mThumbDrawable; private ColorStateList mThumbTintList = null; private PorterDuff.Mode mThumbTintMode = null; private boolean mHasThumbTint = false; private boolean mHasThumbTintMode = false; @UnsupportedAppUsage private Drawable mTrackDrawable; private ColorStateList mTrackTintList = null; private PorterDuff.Mode mTrackTintMode = null; private boolean mHasTrackTint = false; private boolean mHasTrackTintMode = false; private int mThumbTextPadding; @UnsupportedAppUsage private int mSwitchMinWidth; private int mSwitchPadding; private boolean mSplitTrack; private CharSequence mTextOn; private CharSequence mTextOff; private boolean mShowText; private boolean mUseFallbackLineSpacing; private int mTouchMode; private int mTouchSlop; private float mTouchX; private float mTouchY; private VelocityTracker mVelocityTracker = VelocityTracker.obtain(); private int mMinFlingVelocity; private float mThumbPosition; /** * Width required to draw the switch track and thumb. Includes padding and * optical bounds for both the track and thumb. */ @UnsupportedAppUsage private int mSwitchWidth; /** * Height required to draw the switch track and thumb. Includes padding and * optical bounds for both the track and thumb. */ @UnsupportedAppUsage private int mSwitchHeight; /** * Width of the thumb's content region. Does not include padding or * optical bounds. */ @UnsupportedAppUsage private int mThumbWidth; /** Left bound for drawing the switch track and thumb. */ private int mSwitchLeft; /** Top bound for drawing the switch track and thumb. */ private int mSwitchTop; /** Right bound for drawing the switch track and thumb. */ private int mSwitchRight; /** Bottom bound for drawing the switch track and thumb. */ private int mSwitchBottom; private TextPaint mTextPaint; private ColorStateList mTextColors; @UnsupportedAppUsage private Layout mOnLayout; @UnsupportedAppUsage private Layout mOffLayout; private TransformationMethod2 mSwitchTransformationMethod; private ObjectAnimator mPositionAnimator; @SuppressWarnings("hiding") private final Rect mTempRect = new Rect(); private static final int[] CHECKED_STATE_SET = { R.attr.state_checked }; /** * Construct a new Switch with default styling. * * @param context The Context that will determine this widget's theming. */ public Switch(Context context) { this(context, null); } /** * Construct a new Switch with default styling, overriding specific style * attributes as requested. * * @param context The Context that will determine this widget's theming. * @param attrs Specification of attributes that should deviate from default styling. */ public Switch(Context context, AttributeSet attrs) { this(context, attrs, com.android.internal.R.attr.switchStyle); } /** * Construct a new Switch with a default style determined by the given theme attribute, * overriding specific style attributes as requested. * * @param context The Context that will determine this widget's theming. * @param attrs Specification of attributes that should deviate from the default styling. * @param defStyleAttr An attribute in the current theme that contains a * reference to a style resource that supplies default values for * the view. Can be 0 to not look for defaults. */ public Switch(Context context, AttributeSet attrs, int defStyleAttr) { this(context, attrs, defStyleAttr, 0); } /** * Construct a new Switch with a default style determined by the given theme * attribute or style resource, overriding specific style attributes as * requested. * * @param context The Context that will determine this widget's theming. * @param attrs Specification of attributes that should deviate from the * default styling. * @param defStyleAttr An attribute in the current theme that contains a * reference to a style resource that supplies default values for * the view. Can be 0 to not look for defaults. * @param defStyleRes A resource identifier of a style resource that * supplies default values for the view, used only if * defStyleAttr is 0 or can not be found in the theme. Can be 0 * to not look for defaults. */ public Switch(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { super(context, attrs, defStyleAttr, defStyleRes); mTextPaint = new TextPaint(Paint.ANTI_ALIAS_FLAG); final Resources res = getResources(); mTextPaint.density = res.getDisplayMetrics().density; mTextPaint.setCompatibilityScaling(res.getCompatibilityInfo().applicationScale); final TypedArray a = context.obtainStyledAttributes(attrs, com.android.internal.R.styleable.Switch, defStyleAttr, defStyleRes); mThumbDrawable = a.getDrawable(com.android.internal.R.styleable.Switch_thumb); if (mThumbDrawable != null) { mThumbDrawable.setCallback(this); } mTrackDrawable = a.getDrawable(com.android.internal.R.styleable.Switch_track); if (mTrackDrawable != null) { mTrackDrawable.setCallback(this); } mTextOn = a.getText(com.android.internal.R.styleable.Switch_textOn); mTextOff = a.getText(com.android.internal.R.styleable.Switch_textOff); mShowText = a.getBoolean(com.android.internal.R.styleable.Switch_showText, true); mThumbTextPadding = a.getDimensionPixelSize(com.android.internal.R.styleable.Switch_thumbTextPadding, 0); mSwitchMinWidth = a.getDimensionPixelSize(com.android.internal.R.styleable.Switch_switchMinWidth, 0); mSwitchPadding = a.getDimensionPixelSize(com.android.internal.R.styleable.Switch_switchPadding, 0); mSplitTrack = a.getBoolean(com.android.internal.R.styleable.Switch_splitTrack, false); mUseFallbackLineSpacing = context.getApplicationInfo().targetSdkVersion >= VERSION_CODES.P; ColorStateList thumbTintList = a.getColorStateList(com.android.internal.R.styleable.Switch_thumbTint); if (thumbTintList != null) { mThumbTintList = thumbTintList; mHasThumbTint = true; } PorterDuff.Mode thumbTintMode = Drawable .parseTintMode(a.getInt(com.android.internal.R.styleable.Switch_thumbTintMode, -1), null); if (mThumbTintMode != thumbTintMode) { mThumbTintMode = thumbTintMode; mHasThumbTintMode = true; } if (mHasThumbTint || mHasThumbTintMode) { applyThumbTint(); } ColorStateList trackTintList = a.getColorStateList(com.android.internal.R.styleable.Switch_trackTint); if (trackTintList != null) { mTrackTintList = trackTintList; mHasTrackTint = true; } PorterDuff.Mode trackTintMode = Drawable .parseTintMode(a.getInt(com.android.internal.R.styleable.Switch_trackTintMode, -1), null); if (mTrackTintMode != trackTintMode) { mTrackTintMode = trackTintMode; mHasTrackTintMode = true; } if (mHasTrackTint || mHasTrackTintMode) { applyTrackTint(); } final int appearance = a.getResourceId(com.android.internal.R.styleable.Switch_switchTextAppearance, 0); if (appearance != 0) { setSwitchTextAppearance(context, appearance); } a.recycle(); final ViewConfiguration config = ViewConfiguration.get(context); mTouchSlop = config.getScaledTouchSlop(); mMinFlingVelocity = config.getScaledMinimumFlingVelocity(); // Refresh display with current params refreshDrawableState(); setChecked(isChecked()); } /** * Sets the switch text color, size, style, hint color, and highlight color * from the specified TextAppearance resource. * * @attr ref android.R.styleable#Switch_switchTextAppearance */ public void setSwitchTextAppearance(Context context, @StyleRes int resid) { TypedArray appearance = context.obtainStyledAttributes(resid, com.android.internal.R.styleable.TextAppearance); ColorStateList colors; int ts; colors = appearance.getColorStateList(com.android.internal.R.styleable.TextAppearance_textColor); if (colors != null) { mTextColors = colors; } else { // If no color set in TextAppearance, default to the view's textColor mTextColors = getTextColors(); } ts = appearance.getDimensionPixelSize(com.android.internal.R.styleable.TextAppearance_textSize, 0); if (ts != 0) { if (ts != mTextPaint.getTextSize()) { mTextPaint.setTextSize(ts); requestLayout(); } } int typefaceIndex, styleIndex; typefaceIndex = appearance.getInt(com.android.internal.R.styleable.TextAppearance_typeface, -1); styleIndex = appearance.getInt(com.android.internal.R.styleable.TextAppearance_textStyle, -1); setSwitchTypefaceByIndex(typefaceIndex, styleIndex); boolean allCaps = appearance.getBoolean(com.android.internal.R.styleable.TextAppearance_textAllCaps, false); if (allCaps) { mSwitchTransformationMethod = new AllCapsTransformationMethod(getContext()); mSwitchTransformationMethod.setLengthChangesAllowed(true); } else { mSwitchTransformationMethod = null; } appearance.recycle(); } private void setSwitchTypefaceByIndex(int typefaceIndex, int styleIndex) { Typeface tf = null; switch (typefaceIndex) { case SANS: tf = Typeface.SANS_SERIF; break; case SERIF: tf = Typeface.SERIF; break; case MONOSPACE: tf = Typeface.MONOSPACE; break; } setSwitchTypeface(tf, styleIndex); } /** * Sets the typeface and style in which the text should be displayed on the * switch, and turns on the fake bold and italic bits in the Paint if the * Typeface that you provided does not have all the bits in the * style that you specified. */ public void setSwitchTypeface(Typeface tf, int style) { if (style > 0) { if (tf == null) { tf = Typeface.defaultFromStyle(style); } else { tf = Typeface.create(tf, style); } setSwitchTypeface(tf); // now compute what (if any) algorithmic styling is needed int typefaceStyle = tf != null ? tf.getStyle() : 0; int need = style & ~typefaceStyle; mTextPaint.setFakeBoldText((need & Typeface.BOLD) != 0); mTextPaint.setTextSkewX((need & Typeface.ITALIC) != 0 ? -0.25f : 0); } else { mTextPaint.setFakeBoldText(false); mTextPaint.setTextSkewX(0); setSwitchTypeface(tf); } } /** * Sets the typeface in which the text should be displayed on the switch. * Note that not all Typeface families actually have bold and italic * variants, so you may need to use * {@link #setSwitchTypeface(Typeface, int)} to get the appearance * that you actually want. * * @attr ref android.R.styleable#TextView_typeface * @attr ref android.R.styleable#TextView_textStyle */ public void setSwitchTypeface(Typeface tf) { if (mTextPaint.getTypeface() != tf) { mTextPaint.setTypeface(tf); requestLayout(); invalidate(); } } /** * Set the amount of horizontal padding between the switch and the associated text. * * @param pixels Amount of padding in pixels * * @attr ref android.R.styleable#Switch_switchPadding */ public void setSwitchPadding(int pixels) { mSwitchPadding = pixels; requestLayout(); } /** * Get the amount of horizontal padding between the switch and the associated text. * * @return Amount of padding in pixels * * @attr ref android.R.styleable#Switch_switchPadding */ public int getSwitchPadding() { return mSwitchPadding; } /** * Set the minimum width of the switch in pixels. The switch's width will be the maximum * of this value and its measured width as determined by the switch drawables and text used. * * @param pixels Minimum width of the switch in pixels * * @attr ref android.R.styleable#Switch_switchMinWidth */ public void setSwitchMinWidth(int pixels) { mSwitchMinWidth = pixels; requestLayout(); } /** * Get the minimum width of the switch in pixels. The switch's width will be the maximum * of this value and its measured width as determined by the switch drawables and text used. * * @return Minimum width of the switch in pixels * * @attr ref android.R.styleable#Switch_switchMinWidth */ public int getSwitchMinWidth() { return mSwitchMinWidth; } /** * Set the horizontal padding around the text drawn on the switch itself. * * @param pixels Horizontal padding for switch thumb text in pixels * * @attr ref android.R.styleable#Switch_thumbTextPadding */ public void setThumbTextPadding(int pixels) { mThumbTextPadding = pixels; requestLayout(); } /** * Get the horizontal padding around the text drawn on the switch itself. * * @return Horizontal padding for switch thumb text in pixels * * @attr ref android.R.styleable#Switch_thumbTextPadding */ public int getThumbTextPadding() { return mThumbTextPadding; } /** * Set the drawable used for the track that the switch slides within. * * @param track Track drawable * * @attr ref android.R.styleable#Switch_track */ public void setTrackDrawable(Drawable track) { if (mTrackDrawable != null) { mTrackDrawable.setCallback(null); } mTrackDrawable = track; if (track != null) { track.setCallback(this); } requestLayout(); } /** * Set the drawable used for the track that the switch slides within. * * @param resId Resource ID of a track drawable * * @attr ref android.R.styleable#Switch_track */ public void setTrackResource(@DrawableRes int resId) { setTrackDrawable(getContext().getDrawable(resId)); } /** * Get the drawable used for the track that the switch slides within. * * @return Track drawable * * @attr ref android.R.styleable#Switch_track */ public Drawable getTrackDrawable() { return mTrackDrawable; } /** * Applies a tint to the track drawable. Does not modify the current * tint mode, which is {@link PorterDuff.Mode#SRC_IN} by default. * <p> * Subsequent calls to {@link #setTrackDrawable(Drawable)} will * automatically mutate the drawable and apply the specified tint and tint * mode using {@link Drawable#setTintList(ColorStateList)}. * * @param tint the tint to apply, may be {@code null} to clear tint * * @attr ref android.R.styleable#Switch_trackTint * @see #getTrackTintList() * @see Drawable#setTintList(ColorStateList) */ public void setTrackTintList(@Nullable ColorStateList tint) { mTrackTintList = tint; mHasTrackTint = true; applyTrackTint(); } /** * @return the tint applied to the track drawable * @attr ref android.R.styleable#Switch_trackTint * @see #setTrackTintList(ColorStateList) */ @Nullable public ColorStateList getTrackTintList() { return mTrackTintList; } /** * Specifies the blending mode used to apply the tint specified by * {@link #setTrackTintList(ColorStateList)}} to the track drawable. * The default mode is {@link PorterDuff.Mode#SRC_IN}. * * @param tintMode the blending mode used to apply the tint, may be * {@code null} to clear tint * @attr ref android.R.styleable#Switch_trackTintMode * @see #getTrackTintMode() * @see Drawable#setTintMode(PorterDuff.Mode) */ public void setTrackTintMode(@Nullable PorterDuff.Mode tintMode) { mTrackTintMode = tintMode; mHasTrackTintMode = true; applyTrackTint(); } /** * @return the blending mode used to apply the tint to the track * drawable * @attr ref android.R.styleable#Switch_trackTintMode * @see #setTrackTintMode(PorterDuff.Mode) */ @Nullable public PorterDuff.Mode getTrackTintMode() { return mTrackTintMode; } private void applyTrackTint() { if (mTrackDrawable != null && (mHasTrackTint || mHasTrackTintMode)) { mTrackDrawable = mTrackDrawable.mutate(); if (mHasTrackTint) { mTrackDrawable.setTintList(mTrackTintList); } if (mHasTrackTintMode) { mTrackDrawable.setTintMode(mTrackTintMode); } // The drawable (or one of its children) may not have been // stateful before applying the tint, so let's try again. if (mTrackDrawable.isStateful()) { mTrackDrawable.setState(getDrawableState()); } } } /** * Set the drawable used for the switch "thumb" - the piece that the user * can physically touch and drag along the track. * * @param thumb Thumb drawable * * @attr ref android.R.styleable#Switch_thumb */ public void setThumbDrawable(Drawable thumb) { if (mThumbDrawable != null) { mThumbDrawable.setCallback(null); } mThumbDrawable = thumb; if (thumb != null) { thumb.setCallback(this); } requestLayout(); } /** * Set the drawable used for the switch "thumb" - the piece that the user * can physically touch and drag along the track. * * @param resId Resource ID of a thumb drawable * * @attr ref android.R.styleable#Switch_thumb */ public void setThumbResource(@DrawableRes int resId) { setThumbDrawable(getContext().getDrawable(resId)); } /** * Get the drawable used for the switch "thumb" - the piece that the user * can physically touch and drag along the track. * * @return Thumb drawable * * @attr ref android.R.styleable#Switch_thumb */ public Drawable getThumbDrawable() { return mThumbDrawable; } /** * Applies a tint to the thumb drawable. Does not modify the current * tint mode, which is {@link PorterDuff.Mode#SRC_IN} by default. * <p> * Subsequent calls to {@link #setThumbDrawable(Drawable)} will * automatically mutate the drawable and apply the specified tint and tint * mode using {@link Drawable#setTintList(ColorStateList)}. * * @param tint the tint to apply, may be {@code null} to clear tint * * @attr ref android.R.styleable#Switch_thumbTint * @see #getThumbTintList() * @see Drawable#setTintList(ColorStateList) */ public void setThumbTintList(@Nullable ColorStateList tint) { mThumbTintList = tint; mHasThumbTint = true; applyThumbTint(); } /** * @return the tint applied to the thumb drawable * @attr ref android.R.styleable#Switch_thumbTint * @see #setThumbTintList(ColorStateList) */ @Nullable public ColorStateList getThumbTintList() { return mThumbTintList; } /** * Specifies the blending mode used to apply the tint specified by * {@link #setThumbTintList(ColorStateList)}} to the thumb drawable. * The default mode is {@link PorterDuff.Mode#SRC_IN}. * * @param tintMode the blending mode used to apply the tint, may be * {@code null} to clear tint * @attr ref android.R.styleable#Switch_thumbTintMode * @see #getThumbTintMode() * @see Drawable#setTintMode(PorterDuff.Mode) */ public void setThumbTintMode(@Nullable PorterDuff.Mode tintMode) { mThumbTintMode = tintMode; mHasThumbTintMode = true; applyThumbTint(); } /** * @return the blending mode used to apply the tint to the thumb * drawable * @attr ref android.R.styleable#Switch_thumbTintMode * @see #setThumbTintMode(PorterDuff.Mode) */ @Nullable public PorterDuff.Mode getThumbTintMode() { return mThumbTintMode; } private void applyThumbTint() { if (mThumbDrawable != null && (mHasThumbTint || mHasThumbTintMode)) { mThumbDrawable = mThumbDrawable.mutate(); if (mHasThumbTint) { mThumbDrawable.setTintList(mThumbTintList); } if (mHasThumbTintMode) { mThumbDrawable.setTintMode(mThumbTintMode); } // The drawable (or one of its children) may not have been // stateful before applying the tint, so let's try again. if (mThumbDrawable.isStateful()) { mThumbDrawable.setState(getDrawableState()); } } } /** * Specifies whether the track should be split by the thumb. When true, * the thumb's optical bounds will be clipped out of the track drawable, * then the thumb will be drawn into the resulting gap. * * @param splitTrack Whether the track should be split by the thumb * * @attr ref android.R.styleable#Switch_splitTrack */ public void setSplitTrack(boolean splitTrack) { mSplitTrack = splitTrack; invalidate(); } /** * Returns whether the track should be split by the thumb. * * @attr ref android.R.styleable#Switch_splitTrack */ public boolean getSplitTrack() { return mSplitTrack; } /** * Returns the text displayed when the button is in the checked state. * * @attr ref android.R.styleable#Switch_textOn */ public CharSequence getTextOn() { return mTextOn; } /** * Sets the text displayed when the button is in the checked state. * * @attr ref android.R.styleable#Switch_textOn */ public void setTextOn(CharSequence textOn) { mTextOn = textOn; requestLayout(); } /** * Returns the text displayed when the button is not in the checked state. * * @attr ref android.R.styleable#Switch_textOff */ public CharSequence getTextOff() { return mTextOff; } /** * Sets the text displayed when the button is not in the checked state. * * @attr ref android.R.styleable#Switch_textOff */ public void setTextOff(CharSequence textOff) { mTextOff = textOff; requestLayout(); } /** * Sets whether the on/off text should be displayed. * * @param showText {@code true} to display on/off text * @attr ref android.R.styleable#Switch_showText */ public void setShowText(boolean showText) { if (mShowText != showText) { mShowText = showText; requestLayout(); } } /** * @return whether the on/off text should be displayed * @attr ref android.R.styleable#Switch_showText */ public boolean getShowText() { return mShowText; } @Override public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { if (mShowText) { if (mOnLayout == null) { mOnLayout = makeLayout(mTextOn); } if (mOffLayout == null) { mOffLayout = makeLayout(mTextOff); } } final Rect padding = mTempRect; final int thumbWidth; final int thumbHeight; if (mThumbDrawable != null) { // Cached thumb width does not include padding. mThumbDrawable.getPadding(padding); thumbWidth = mThumbDrawable.getIntrinsicWidth() - padding.left - padding.right; thumbHeight = mThumbDrawable.getIntrinsicHeight(); } else { thumbWidth = 0; thumbHeight = 0; } final int maxTextWidth; if (mShowText) { maxTextWidth = Math.max(mOnLayout.getWidth(), mOffLayout.getWidth()) + mThumbTextPadding * 2; } else { maxTextWidth = 0; } mThumbWidth = Math.max(maxTextWidth, thumbWidth); final int trackHeight; if (mTrackDrawable != null) { mTrackDrawable.getPadding(padding); trackHeight = mTrackDrawable.getIntrinsicHeight(); } else { padding.setEmpty(); trackHeight = 0; } // Adjust left and right padding to ensure there's enough room for the // thumb's padding (when present). int paddingLeft = padding.left; int paddingRight = padding.right; if (mThumbDrawable != null) { final Insets inset = mThumbDrawable.getOpticalInsets(); paddingLeft = Math.max(paddingLeft, inset.left); paddingRight = Math.max(paddingRight, inset.right); } final int switchWidth = Math.max(mSwitchMinWidth, 2 * mThumbWidth + paddingLeft + paddingRight); final int switchHeight = Math.max(trackHeight, thumbHeight); mSwitchWidth = switchWidth; mSwitchHeight = switchHeight; super.onMeasure(widthMeasureSpec, heightMeasureSpec); final int measuredHeight = getMeasuredHeight(); if (measuredHeight < switchHeight) { setMeasuredDimension(getMeasuredWidthAndState(), switchHeight); } } /** @hide */ @Override public void onPopulateAccessibilityEventInternal(AccessibilityEvent event) { super.onPopulateAccessibilityEventInternal(event); final CharSequence text = isChecked() ? mTextOn : mTextOff; if (text != null) { event.getText().add(text); } } private Layout makeLayout(CharSequence text) { final CharSequence transformed = (mSwitchTransformationMethod != null) ? mSwitchTransformationMethod.getTransformation(text, this) : text; int width = (int) Math.ceil(Layout.getDesiredWidth(transformed, 0, transformed.length(), mTextPaint, getTextDirectionHeuristic())); return StaticLayout.Builder.obtain(transformed, 0, transformed.length(), mTextPaint, width) .setUseLineSpacingFromFallbacks(mUseFallbackLineSpacing).build(); } /** * @return true if (x, y) is within the target area of the switch thumb */ private boolean hitThumb(float x, float y) { if (mThumbDrawable == null) { return false; } // Relies on mTempRect, MUST be called first! final int thumbOffset = getThumbOffset(); mThumbDrawable.getPadding(mTempRect); final int thumbTop = mSwitchTop - mTouchSlop; final int thumbLeft = mSwitchLeft + thumbOffset - mTouchSlop; final int thumbRight = thumbLeft + mThumbWidth + mTempRect.left + mTempRect.right + mTouchSlop; final int thumbBottom = mSwitchBottom + mTouchSlop; return x > thumbLeft && x < thumbRight && y > thumbTop && y < thumbBottom; } @Override public boolean onTouchEvent(MotionEvent ev) { mVelocityTracker.addMovement(ev); final int action = ev.getActionMasked(); switch (action) { case MotionEvent.ACTION_DOWN: { final float x = ev.getX(); final float y = ev.getY(); if (isEnabled() && hitThumb(x, y)) { mTouchMode = TOUCH_MODE_DOWN; mTouchX = x; mTouchY = y; } break; } case MotionEvent.ACTION_MOVE: { switch (mTouchMode) { case TOUCH_MODE_IDLE: // Didn't target the thumb, treat normally. break; case TOUCH_MODE_DOWN: { final float x = ev.getX(); final float y = ev.getY(); if (Math.abs(x - mTouchX) > mTouchSlop || Math.abs(y - mTouchY) > mTouchSlop) { mTouchMode = TOUCH_MODE_DRAGGING; getParent().requestDisallowInterceptTouchEvent(true); mTouchX = x; mTouchY = y; return true; } break; } case TOUCH_MODE_DRAGGING: { final float x = ev.getX(); final int thumbScrollRange = getThumbScrollRange(); final float thumbScrollOffset = x - mTouchX; float dPos; if (thumbScrollRange != 0) { dPos = thumbScrollOffset / thumbScrollRange; } else { // If the thumb scroll range is empty, just use the // movement direction to snap on or off. dPos = thumbScrollOffset > 0 ? 1 : -1; } if (isLayoutRtl()) { dPos = -dPos; } final float newPos = MathUtils.constrain(mThumbPosition + dPos, 0, 1); if (newPos != mThumbPosition) { mTouchX = x; setThumbPosition(newPos); } return true; } } break; } case MotionEvent.ACTION_UP: case MotionEvent.ACTION_CANCEL: { if (mTouchMode == TOUCH_MODE_DRAGGING) { stopDrag(ev); // Allow super class to handle pressed state, etc. super.onTouchEvent(ev); return true; } mTouchMode = TOUCH_MODE_IDLE; mVelocityTracker.clear(); break; } } return super.onTouchEvent(ev); } private void cancelSuperTouch(MotionEvent ev) { MotionEvent cancel = MotionEvent.obtain(ev); cancel.setAction(MotionEvent.ACTION_CANCEL); super.onTouchEvent(cancel); cancel.recycle(); } /** * Called from onTouchEvent to end a drag operation. * * @param ev Event that triggered the end of drag mode - ACTION_UP or ACTION_CANCEL */ private void stopDrag(MotionEvent ev) { mTouchMode = TOUCH_MODE_IDLE; // Commit the change if the event is up and not canceled and the switch // has not been disabled during the drag. final boolean commitChange = ev.getAction() == MotionEvent.ACTION_UP && isEnabled(); final boolean oldState = isChecked(); final boolean newState; if (commitChange) { mVelocityTracker.computeCurrentVelocity(1000); final float xvel = mVelocityTracker.getXVelocity(); if (Math.abs(xvel) > mMinFlingVelocity) { newState = isLayoutRtl() ? (xvel < 0) : (xvel > 0); } else { newState = getTargetCheckedState(); } } else { newState = oldState; } if (newState != oldState) { playSoundEffect(SoundEffectConstants.CLICK); } // Always call setChecked so that the thumb is moved back to the correct edge setChecked(newState); cancelSuperTouch(ev); } private void animateThumbToCheckedState(boolean newCheckedState) { final float targetPosition = newCheckedState ? 1 : 0; mPositionAnimator = ObjectAnimator.ofFloat(this, THUMB_POS, targetPosition); mPositionAnimator.setDuration(THUMB_ANIMATION_DURATION); mPositionAnimator.setAutoCancel(true); mPositionAnimator.start(); } @UnsupportedAppUsage private void cancelPositionAnimator() { if (mPositionAnimator != null) { mPositionAnimator.cancel(); } } private boolean getTargetCheckedState() { return mThumbPosition > 0.5f; } /** * Sets the thumb position as a decimal value between 0 (off) and 1 (on). * * @param position new position between [0,1] */ @UnsupportedAppUsage private void setThumbPosition(float position) { mThumbPosition = position; invalidate(); } @Override public void toggle() { setChecked(!isChecked()); } @Override public void setChecked(boolean checked) { super.setChecked(checked); // Calling the super method may result in setChecked() getting called // recursively with a different value, so load the REAL value... checked = isChecked(); if (isAttachedToWindow() && isLaidOut()) { animateThumbToCheckedState(checked); } else { // Immediately move the thumb to the new position. cancelPositionAnimator(); setThumbPosition(checked ? 1 : 0); } } @Override protected void onLayout(boolean changed, int left, int top, int right, int bottom) { super.onLayout(changed, left, top, right, bottom); int opticalInsetLeft = 0; int opticalInsetRight = 0; if (mThumbDrawable != null) { final Rect trackPadding = mTempRect; if (mTrackDrawable != null) { mTrackDrawable.getPadding(trackPadding); } else { trackPadding.setEmpty(); } final Insets insets = mThumbDrawable.getOpticalInsets(); opticalInsetLeft = Math.max(0, insets.left - trackPadding.left); opticalInsetRight = Math.max(0, insets.right - trackPadding.right); } final int switchRight; final int switchLeft; if (isLayoutRtl()) { switchLeft = getPaddingLeft() + opticalInsetLeft; switchRight = switchLeft + mSwitchWidth - opticalInsetLeft - opticalInsetRight; } else { switchRight = getWidth() - getPaddingRight() - opticalInsetRight; switchLeft = switchRight - mSwitchWidth + opticalInsetLeft + opticalInsetRight; } final int switchTop; final int switchBottom; switch (getGravity() & Gravity.VERTICAL_GRAVITY_MASK) { default: case Gravity.TOP: switchTop = getPaddingTop(); switchBottom = switchTop + mSwitchHeight; break; case Gravity.CENTER_VERTICAL: switchTop = (getPaddingTop() + getHeight() - getPaddingBottom()) / 2 - mSwitchHeight / 2; switchBottom = switchTop + mSwitchHeight; break; case Gravity.BOTTOM: switchBottom = getHeight() - getPaddingBottom(); switchTop = switchBottom - mSwitchHeight; break; } mSwitchLeft = switchLeft; mSwitchTop = switchTop; mSwitchBottom = switchBottom; mSwitchRight = switchRight; } @Override public void draw(Canvas c) { final Rect padding = mTempRect; final int switchLeft = mSwitchLeft; final int switchTop = mSwitchTop; final int switchRight = mSwitchRight; final int switchBottom = mSwitchBottom; int thumbInitialLeft = switchLeft + getThumbOffset(); final Insets thumbInsets; if (mThumbDrawable != null) { thumbInsets = mThumbDrawable.getOpticalInsets(); } else { thumbInsets = Insets.NONE; } // Layout the track. if (mTrackDrawable != null) { mTrackDrawable.getPadding(padding); // Adjust thumb position for track padding. thumbInitialLeft += padding.left; // If necessary, offset by the optical insets of the thumb asset. int trackLeft = switchLeft; int trackTop = switchTop; int trackRight = switchRight; int trackBottom = switchBottom; if (thumbInsets != Insets.NONE) { if (thumbInsets.left > padding.left) { trackLeft += thumbInsets.left - padding.left; } if (thumbInsets.top > padding.top) { trackTop += thumbInsets.top - padding.top; } if (thumbInsets.right > padding.right) { trackRight -= thumbInsets.right - padding.right; } if (thumbInsets.bottom > padding.bottom) { trackBottom -= thumbInsets.bottom - padding.bottom; } } mTrackDrawable.setBounds(trackLeft, trackTop, trackRight, trackBottom); } // Layout the thumb. if (mThumbDrawable != null) { mThumbDrawable.getPadding(padding); final int thumbLeft = thumbInitialLeft - padding.left; final int thumbRight = thumbInitialLeft + mThumbWidth + padding.right; mThumbDrawable.setBounds(thumbLeft, switchTop, thumbRight, switchBottom); final Drawable background = getBackground(); if (background != null) { background.setHotspotBounds(thumbLeft, switchTop, thumbRight, switchBottom); } } // Draw the background. super.draw(c); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); final Rect padding = mTempRect; final Drawable trackDrawable = mTrackDrawable; if (trackDrawable != null) { trackDrawable.getPadding(padding); } else { padding.setEmpty(); } final int switchTop = mSwitchTop; final int switchBottom = mSwitchBottom; final int switchInnerTop = switchTop + padding.top; final int switchInnerBottom = switchBottom - padding.bottom; final Drawable thumbDrawable = mThumbDrawable; if (trackDrawable != null) { if (mSplitTrack && thumbDrawable != null) { final Insets insets = thumbDrawable.getOpticalInsets(); thumbDrawable.copyBounds(padding); padding.left += insets.left; padding.right -= insets.right; final int saveCount = canvas.save(); canvas.clipRect(padding, Op.DIFFERENCE); trackDrawable.draw(canvas); canvas.restoreToCount(saveCount); } else { trackDrawable.draw(canvas); } } final int saveCount = canvas.save(); if (thumbDrawable != null) { thumbDrawable.draw(canvas); } final Layout switchText = getTargetCheckedState() ? mOnLayout : mOffLayout; if (switchText != null) { final int drawableState[] = getDrawableState(); if (mTextColors != null) { mTextPaint.setColor(mTextColors.getColorForState(drawableState, 0)); } mTextPaint.drawableState = drawableState; final int cX; if (thumbDrawable != null) { final Rect bounds = thumbDrawable.getBounds(); cX = bounds.left + bounds.right; } else { cX = getWidth(); } final int left = cX / 2 - switchText.getWidth() / 2; final int top = (switchInnerTop + switchInnerBottom) / 2 - switchText.getHeight() / 2; canvas.translate(left, top); switchText.draw(canvas); } canvas.restoreToCount(saveCount); } @Override public int getCompoundPaddingLeft() { if (!isLayoutRtl()) { return super.getCompoundPaddingLeft(); } int padding = super.getCompoundPaddingLeft() + mSwitchWidth; if (!TextUtils.isEmpty(getText())) { padding += mSwitchPadding; } return padding; } @Override public int getCompoundPaddingRight() { if (isLayoutRtl()) { return super.getCompoundPaddingRight(); } int padding = super.getCompoundPaddingRight() + mSwitchWidth; if (!TextUtils.isEmpty(getText())) { padding += mSwitchPadding; } return padding; } /** * Translates thumb position to offset according to current RTL setting and * thumb scroll range. Accounts for both track and thumb padding. * * @return thumb offset */ private int getThumbOffset() { final float thumbPosition; if (isLayoutRtl()) { thumbPosition = 1 - mThumbPosition; } else { thumbPosition = mThumbPosition; } return (int) (thumbPosition * getThumbScrollRange() + 0.5f); } private int getThumbScrollRange() { if (mTrackDrawable != null) { final Rect padding = mTempRect; mTrackDrawable.getPadding(padding); final Insets insets; if (mThumbDrawable != null) { insets = mThumbDrawable.getOpticalInsets(); } else { insets = Insets.NONE; } return mSwitchWidth - mThumbWidth - padding.left - padding.right - insets.left - insets.right; } else { return 0; } } @Override protected int[] onCreateDrawableState(int extraSpace) { final int[] drawableState = super.onCreateDrawableState(extraSpace + 1); if (isChecked()) { mergeDrawableStates(drawableState, CHECKED_STATE_SET); } return drawableState; } @Override protected void drawableStateChanged() { super.drawableStateChanged(); final int[] state = getDrawableState(); boolean changed = false; final Drawable thumbDrawable = mThumbDrawable; if (thumbDrawable != null && thumbDrawable.isStateful()) { changed |= thumbDrawable.setState(state); } final Drawable trackDrawable = mTrackDrawable; if (trackDrawable != null && trackDrawable.isStateful()) { changed |= trackDrawable.setState(state); } if (changed) { invalidate(); } } @Override public void drawableHotspotChanged(float x, float y) { super.drawableHotspotChanged(x, y); if (mThumbDrawable != null) { mThumbDrawable.setHotspot(x, y); } if (mTrackDrawable != null) { mTrackDrawable.setHotspot(x, y); } } @Override protected boolean verifyDrawable(@NonNull Drawable who) { return super.verifyDrawable(who) || who == mThumbDrawable || who == mTrackDrawable; } @Override public void jumpDrawablesToCurrentState() { super.jumpDrawablesToCurrentState(); if (mThumbDrawable != null) { mThumbDrawable.jumpToCurrentState(); } if (mTrackDrawable != null) { mTrackDrawable.jumpToCurrentState(); } if (mPositionAnimator != null && mPositionAnimator.isStarted()) { mPositionAnimator.end(); mPositionAnimator = null; } } @Override public CharSequence getAccessibilityClassName() { return Switch.class.getName(); } @Override public void onProvideStructure(ViewStructure structure) { super.onProvideStructure(structure); onProvideAutoFillStructureForAssistOrAutofill(structure); } @Override public void onProvideAutofillStructure(ViewStructure structure, int flags) { super.onProvideAutofillStructure(structure, flags); onProvideAutoFillStructureForAssistOrAutofill(structure); } // NOTE: currently there is no difference for Assist or AutoFill, so it doesn't take flags private void onProvideAutoFillStructureForAssistOrAutofill(ViewStructure structure) { CharSequence switchText = isChecked() ? mTextOn : mTextOff; if (!TextUtils.isEmpty(switchText)) { CharSequence oldText = structure.getText(); if (TextUtils.isEmpty(oldText)) { structure.setText(switchText); } else { StringBuilder newText = new StringBuilder(); newText.append(oldText).append(' ').append(switchText); structure.setText(newText); } // The style of the label text is provided via the base TextView class. This is more // relevant than the style of the (optional) on/off text on the switch button itself, // so ignore the size/color/style stored this.mTextPaint. } } /** @hide */ @Override public void onInitializeAccessibilityNodeInfoInternal(AccessibilityNodeInfo info) { super.onInitializeAccessibilityNodeInfoInternal(info); CharSequence switchText = isChecked() ? mTextOn : mTextOff; if (!TextUtils.isEmpty(switchText)) { CharSequence oldText = info.getText(); if (TextUtils.isEmpty(oldText)) { info.setText(switchText); } else { StringBuilder newText = new StringBuilder(); newText.append(oldText).append(' ').append(switchText); info.setText(newText); } } } private static final FloatProperty<Switch> THUMB_POS = new FloatProperty<Switch>("thumbPos") { @Override public Float get(Switch object) { return object.mThumbPosition; } @Override public void setValue(Switch object, float value) { object.setThumbPosition(value); } }; }