The slider can function either as a continuous slider, or as a discrete slider. The mode of * operation is controlled by the value of the step size. If the step size is set to 0, the slider * operates as a continuous slider where the slider's thumb can be moved to any position along the * horizontal line. If the step size is set to a number greater than 0, the slider operates as a * discrete slider where the slider's thumb will snap to the closest valid value. See {@link * #setStepSize(float)}. * *
The {@link OnChangeListener} interface defines a callback to be invoked when the slider * changes. * *
The {@link LabelFormatter} interface defines a formatter to be used to render text within the * value indicator label on interaction. * *
{@link BasicLabelFormatter} is a simple implementation of the {@link LabelFormatter} that * displays the selected value using letters to indicate magnitude (e.g.: 1.5K, 3M, 12B, etc..). * *
With the default style {@link * com.google.android.material.R.style.Widget_MaterialComponents_Slider}, colorPrimary and * colorOnPrimary are used to customize the color of the slider when enabled, and colorOnSurface is * used when disabled. The following attributes are used to customize the slider's appearance * further: * *
The following XML attributes are used to set the slider's various parameters of operation: * *
Note: the slider does not accept {@link View.OnFocusChangeListener}s.
*
* @attr ref com.google.android.material.R.styleable#Slider_android_stepSize
* @attr ref com.google.android.material.R.styleable#Slider_android_value
* @attr ref com.google.android.material.R.styleable#Slider_android_valueFrom
* @attr ref com.google.android.material.R.styleable#Slider_android_valueTo
* @attr ref com.google.android.material.R.styleable#Slider_haloColor
* @attr ref com.google.android.material.R.styleable#Slider_haloRadius
* @attr ref com.google.android.material.R.styleable#Slider_labelBehavior
* @attr ref com.google.android.material.R.styleable#Slider_labelStyle
* @attr ref com.google.android.material.R.styleable#Slider_thumbColor
* @attr ref com.google.android.material.R.styleable#Slider_thumbElevation
* @attr ref com.google.android.material.R.styleable#Slider_thumbRadius
* @attr ref com.google.android.material.R.styleable#Slider_tickColor
* @attr ref com.google.android.material.R.styleable#Slider_tickColorActive
* @attr ref com.google.android.material.R.styleable#Slider_tickColorInactive
* @attr ref com.google.android.material.R.styleable#Slider_trackColor
* @attr ref com.google.android.material.R.styleable#Slider_trackColorActive
* @attr ref com.google.android.material.R.styleable#Slider_trackColorInactive
* @attr ref com.google.android.material.R.styleable#Slider_trackHeight
*/
public class Slider extends View {
private static final String TAG = Slider.class.getSimpleName();
private static final String EXCEPTION_ILLEGAL_VALUE =
"Slider value must be greater or equal to valueFrom, and lower or equal to valueTo";
private static final String EXCEPTION_ILLEGAL_DISCRETE_VALUE =
"Value must be equal to valueFrom plus a multiple of stepSize when using stepSize";
private static final String EXCEPTION_ILLEGAL_VALUE_FROM =
"valueFrom must be smaller than valueTo";
private static final String EXCEPTION_ILLEGAL_VALUE_TO = "valueTo must be greater than valueFrom";
private static final String EXCEPTION_ILLEGAL_STEP_SIZE =
"The stepSize must be 0, or a factor of the valueFrom-valueTo range";
private static final int HALO_ALPHA = 63;
private static final double THRESHOLD = .0001;
private static final int DEF_STYLE_RES = R.style.Widget_MaterialComponents_Slider;
@NonNull private final Paint inactiveTrackPaint;
@NonNull private final Paint activeTrackPaint;
@NonNull private final Paint thumbPaint;
@NonNull private final Paint haloPaint;
@NonNull private final Paint inactiveTicksPaint;
@NonNull private final Paint activeTicksPaint;
@NonNull private TooltipDrawable label;
@NonNull private List The {@code valueFrom} value must be strictly lower than the {@code valueTo} value. If that
* is not the case, an {@link IllegalArgumentException} will be thrown.
*
* @param valueFrom The minimum value for the slider's range of values
* @throws IllegalArgumentException If {@code valueFrom} is greater or equal to {@code valueTo}
* @see #getValueFrom()
* @attr ref com.google.android.material.R.styleable#Slider_android_valueFrom
*/
public void setValueFrom(float valueFrom) {
this.valueFrom = valueFrom;
validateValueFrom();
}
/**
* Returns the slider's {@code valueTo} value.
*
* @see #setValueTo(float)
* @attr ref com.google.android.material.R.styleable#Slider_android_valueTo
*/
public float getValueTo() {
return valueTo;
}
/**
* Sets the slider's {@code valueTo} value.
*
* The {@code valueTo} value must be strictly greater than the {@code valueFrom} value. If that
* is not the case, an {@link IllegalArgumentException} will be thrown.
*
* @param valueTo The maximum value for the slider's range of values
* @throws IllegalArgumentException If {@code valueTo} is lesser or equal to {@code valueFrom}
* @see #getValueTo()
* @attr ref com.google.android.material.R.styleable#Slider_android_valueTo
*/
public void setValueTo(float valueTo) {
this.valueTo = valueTo;
validateValueTo();
}
/**
* Returns the value of the slider.
*
* @see #setValue(float)
* @attr ref com.google.android.material.R.styleable#Slider_android_value
*/
public float getValue() {
return thumbPosition * (valueTo - valueFrom) + valueFrom;
}
/**
* Sets the value of the slider.
*
* The thumb value must be greater or equal to {@code valueFrom}, and lesser or equal to {@code
* valueTo}. If that is not the case, an {@link IllegalArgumentException} will be thrown.
*
* If the slider is in discrete mode (i.e. the tick increment value is greater than 0), the
* thumb's value must be set to a value falls on a tick (i.e.: {@code value == valueFrom + x *
* stepSize}, where {@code x} is an integer equal to or greater than 0). If that is not the case,
* an {@link IllegalArgumentException} will be thrown.
*
* @param value The value to which to set the slider
* @throws IllegalArgumentException If the value is not within {@code valueFrom} and {@code
* valueTo}. If stepSize is greater than 0 and value does not fall on a tick
* @see #getValue()
* @attr ref com.google.android.material.R.styleable#Slider_android_value
*/
public void setValue(float value) {
if (isValueValid(value)) {
thumbPosition = (value - valueFrom) / (valueTo - valueFrom);
dispatchOnChanged(false);
invalidate();
}
}
private boolean isValueValid(float value) {
if (value < valueFrom || value > valueTo) {
Log.e(TAG, EXCEPTION_ILLEGAL_VALUE);
return false;
}
if (stepSize > 0.0f && ((valueFrom - value) / stepSize) % 1 > THRESHOLD) {
Log.e(TAG, EXCEPTION_ILLEGAL_DISCRETE_VALUE);
return false;
}
return true;
}
/**
* Returns the step size used to mark the ticks.
*
* A step size of 0 means that the slider is operating in continuous mode. A step size greater
* than 0 means that the slider is operating in discrete mode.
*
* @see #setStepSize(float)
* @attr ref com.google.android.material.R.styleable#Slider_android_stepSize
*/
public float getStepSize() {
return stepSize;
}
/**
* Sets the step size to use to mark the ticks.
*
* Setting this value to 0 will make the slider operate in continuous mode. Setting this value
* to a number greater than 0 will make the slider operate in discrete mode.
*
* The step size must evenly divide the range described by the {@code valueFrom} and {@code
* valueTo}, it must be a factor of the range. If the step size is not a factor of the range, an
* {@link IllegalArgumentException} will be thrown.
*
* Setting this value to a negative value will result in an {@link IllegalArgumentException}.
*
* @param stepSize The interval value at which ticks must be drawn. Set to 0 to operate the slider
* in continuous mode and not have any ticks.
* @throws IllegalArgumentException If the step size is not a factor of the {@code
* valueFrom}-{@code valueTo} range. If the step size is less than 0
* @see #getStepSize()
* @attr ref com.google.android.material.R.styleable#Slider_android_stepSize
*/
public void setStepSize(float stepSize) {
this.stepSize = stepSize;
validateStepSize();
maybeUpdateTrackWidthAndTicksCoordinates();
postInvalidate();
}
/**
* Registers a callback to be invoked when the slider changes.
*
* @param listener The callback to run when the slider changes
*/
public void addOnChangeListener(@Nullable OnChangeListener listener) {
changeListeners.add(listener);
}
/**
* Removes a callback for value changes from this {@link Slider}
*
* @param listener The callback that'll stop receive slider changes
*/
public void removeOnChangeListener(@NonNull OnChangeListener listener) {
changeListeners.remove(listener);
}
/** Removes all instances of {@link Slider.OnChangeListener} attached to this slider */
public void clearOnChangeListeners() {
changeListeners.clear();
}
/**
* Registers a callback to be invoked when the slider touch event is being started or stopped
*
* @param listener The callback to run when the slider starts or stops being touched
*/
public void addOnSliderTouchListener(@NonNull OnSliderTouchListener listener) {
touchListeners.add(listener);
}
/**
* Removes a callback to be invoked when the slider touch event is being started or stopped
*
* @param listener The callback that'll stop be notified when the slider is being touched
*/
public void removeOnSliderTouchListener(@NonNull OnSliderTouchListener listener) {
touchListeners.remove(listener);
}
/** Removes all instances of {@link Slider.OnSliderTouchListener} attached to this slider */
public void clearOnSliderTouchListeners() {
touchListeners.clear();
}
/**
* Returns {@code true} if the slider has a {@link LabelFormatter} attached, {@code false}
* otherwise.
*/
public boolean hasLabelFormatter() {
return formatter != null;
}
/**
* Registers a {@link LabelFormatter} to be used to format the value displayed in the bubble shown
* when the slider operates in discrete mode.
*
* @param formatter The {@link LabelFormatter} to use to format the bubble's text
*/
public void setLabelFormatter(@Nullable LabelFormatter formatter) {
this.formatter = formatter;
}
/**
* Returns the elevation of the thumb.
*
* @see #setThumbElevation(float)
* @see #setThumbElevationResource(int)
* @attr ref com.google.android.material.R.styleable#Slider_thumbElevation
*/
public float getThumbElevation() {
return thumbDrawable.getElevation();
}
/**
* Sets the elevation of the thumb.
*
* @see #getThumbElevation()
* @attr ref com.google.android.material.R.styleable#Slider_thumbElevation
*/
public void setThumbElevation(float elevation) {
thumbDrawable.setElevation(elevation);
}
/**
* Sets the elevation of the thumb from a dimension resource.
*
* @see #getThumbElevation()
* @attr ref com.google.android.material.R.styleable#Slider_thumbElevation
*/
public void setThumbElevationResource(@DimenRes int elevation) {
setThumbElevation(getResources().getDimension(elevation));
}
/**
* Returns the radius of the thumb.
*
* @see #setThumbRadius(int)
* @see #setThumbRadiusResource(int)
* @attr ref com.google.android.material.R.styleable#Slider_thumbRadius
*/
@Dimension
public int getThumbRadius() {
return thumbRadius;
}
/**
* Sets the radius of the thumb in pixels.
*
* @see #getThumbRadius()
* @attr ref com.google.android.material.R.styleable#Slider_thumbRadius
*/
public void setThumbRadius(@IntRange(from = 0) @Dimension int radius) {
if (radius == thumbRadius) {
return;
}
thumbRadius = radius;
thumbDrawable.setShapeAppearanceModel(
ShapeAppearanceModel.builder().setAllCorners(CornerFamily.ROUNDED, thumbRadius).build());
thumbDrawable.setBounds(0, 0, thumbRadius * 2, thumbRadius * 2);
postInvalidate();
}
/**
* Sets the radius of the thumb from a dimension resource.
*
* @see #getThumbRadius()
* @attr ref com.google.android.material.R.styleable#Slider_thumbRadius
*/
public void setThumbRadiusResource(@DimenRes int radius) {
setThumbRadius(getResources().getDimensionPixelSize(radius));
}
/**
* Returns the radius of the halo.
*
* @see #setHaloRadius(int)
* @see #setHaloRadiusResource(int)
* @attr ref com.google.android.material.R.styleable#Slider_haloRadius
*/
@Dimension()
public int getHaloRadius() {
return haloRadius;
}
/**
* Sets the radius of the halo in pixels.
*
* @see #getHaloRadius()
* @attr ref com.google.android.material.R.styleable#Slider_haloRadius
*/
public void setHaloRadius(@IntRange(from = 0) @Dimension int radius) {
if (radius == haloRadius) {
return;
}
haloRadius = radius;
if (!shouldDrawCompatHalo()) {
Drawable background = getBackground();
if (background instanceof RippleDrawable) {
DrawableUtils.setRippleDrawableRadius((RippleDrawable) background, haloRadius);
}
} else {
postInvalidate();
}
}
/**
* Sets the radius of the halo from a dimension resource.
*
* @see #getHaloRadius()
* @attr ref com.google.android.material.R.styleable#Slider_haloRadius
*/
public void setHaloRadiusResource(@DimenRes int radius) {
setHaloRadius(getResources().getDimensionPixelSize(radius));
}
/**
* Returns the {@link LabelBehavior} used.
*
* @see #setLabelBehavior(int)
* @attr ref com.google.android.material.R.styleable#Slider_labelBehavior
*/
@LabelBehavior
public int getLabelBehavior() {
return labelBehavior;
}
/**
* Determines the {@link LabelBehavior} used.
*
* @see LabelBehavior
* @see #getLabelBehavior()
* @attr ref com.google.android.material.R.styleable#Slider_labelBehavior
*/
public void setLabelBehavior(@LabelBehavior int labelBehavior) {
if (this.labelBehavior != labelBehavior) {
this.labelBehavior = labelBehavior;
requestLayout();
}
}
/**
* Returns the height of the track in pixels.
*
* @see #setTrackHeight(int)
* @attr ref com.google.android.material.R.styleable#Slider_trackHeight
*/
@Dimension()
public int getTrackHeight() {
return trackHeight;
}
/**
* Set the height of the track in pixels.
*
* @see #getTrackHeight()
* @attr ref com.google.android.material.R.styleable#Slider_trackHeight
*/
public void setTrackHeight(@IntRange(from = 0) @Dimension int trackHeight) {
if (this.trackHeight != trackHeight) {
this.trackHeight = trackHeight;
invalidateTrack();
maybeUpdateTrackWidthAndTicksCoordinates();
postInvalidate();
}
}
/**
* Returns the color of the halo.
*
* @see #setHaloColor(ColorStateList)
* @attr ref com.google.android.material.R.styleable#Slider_haloColor
*/
@NonNull
public ColorStateList getHaloColor() {
return haloColor;
}
/**
* Sets the color of the halo.
*
* @see #getHaloColor()
* @attr ref com.google.android.material.R.styleable#Slider_haloColor
*/
public void setHaloColor(@NonNull ColorStateList haloColor) {
if (haloColor.equals(this.haloColor)) {
return;
}
this.haloColor = haloColor;
if (!shouldDrawCompatHalo()) {
Drawable background = getBackground();
if (background instanceof RippleDrawable) {
((RippleDrawable) background).setColor(haloColor);
}
} else {
haloPaint.setColor(getColorForState(haloColor));
haloPaint.setAlpha(HALO_ALPHA);
invalidate();
}
}
/**
* Returns the color of the thumb.
*
* @see #setThumbColor(ColorStateList)
* @attr ref com.google.android.material.R.styleable#Slider_thumbColor
*/
@NonNull
public ColorStateList getThumbColor() {
return thumbDrawable.getFillColor();
}
/**
* Sets the color of the thumb.
*
* @see #getThumbColor()
* @attr ref com.google.android.material.R.styleable#Slider_thumbColor
*/
public void setThumbColor(@NonNull ColorStateList thumbColor) {
thumbDrawable.setFillColor(thumbColor);
}
/**
* Returns the color of the tick if the active and inactive parts aren't different.
*
* @throws IllegalStateException If {@code tickColorActive} and {@code tickColorInactive} have
* been set to different values.
* @see #setTickColor(ColorStateList)
* @see #setTickColorInactive(ColorStateList)
* @see #setTickColorActive(ColorStateList)
* @see #getTickColorInactive()
* @see #getTickColorActive()
* @attr ref com.google.android.material.R.styleable#Slider_tickColor
*/
@NonNull
public ColorStateList getTickColor() {
if (!tickColorInactive.equals(tickColorActive)) {
throw new IllegalStateException(
"The inactive and active ticks are different colors. Use the getTickColorInactive() and"
+ " getTickColorActive() methods instead.");
}
return tickColorActive;
}
/**
* Sets the color of the tick marks.
*
* @see #setTickColorInactive(ColorStateList)
* @see #setTickColorActive(ColorStateList)
* @see #getTickColor()
* @attr ref com.google.android.material.R.styleable#Slider_tickColor
*/
public void setTickColor(@NonNull ColorStateList tickColor) {
setTickColorInactive(tickColor);
setTickColorActive(tickColor);
}
/**
* Returns the color of the ticks on the active portion of the track.
*
* @see #setTickColorActive(ColorStateList)
* @see #setTickColor(ColorStateList)
* @see #getTickColor()
* @attr ref com.google.android.material.R.styleable#Slider_tickColorActive
*/
@NonNull
public ColorStateList getTickColorActive() {
return tickColorActive;
}
/**
* Sets the color of the ticks on the active portion of the track.
*
* @see #getTickColorActive()
* @see #setTickColor(ColorStateList)
* @attr ref com.google.android.material.R.styleable#Slider_tickColorActive
*/
public void setTickColorActive(@NonNull ColorStateList tickColor) {
if (tickColor.equals(tickColorActive)) {
return;
}
tickColorActive = tickColor;
activeTicksPaint.setColor(getColorForState(tickColorActive));
invalidate();
}
/**
* Returns the color of the ticks on the inactive portion of the track.
*
* @see #setTickColorInactive(ColorStateList)
* @see #setTickColor(ColorStateList)
* @see #getTickColor()
* @attr ref com.google.android.material.R.styleable#Slider_tickColorInactive
*/
@NonNull
public ColorStateList getTickColorInactive() {
return tickColorInactive;
}
/**
* Sets the color of the ticks on the inactive portion of the track.
*
* @see #getTickColorInactive()
* @see #setTickColor(ColorStateList)
* @attr ref com.google.android.material.R.styleable#Slider_tickColorInactive
*/
public void setTickColorInactive(@NonNull ColorStateList tickColor) {
if (tickColor.equals(tickColorInactive)) {
return;
}
tickColorInactive = tickColor;
inactiveTicksPaint.setColor(getColorForState(tickColorInactive));
invalidate();
}
/**
* Returns the color of the track if the active and inactive parts aren't different.
*
* @throws IllegalStateException If {@code trackColorActive} and {@code trackColorInactive} have
* been set to different values.
* @see #setTrackColor(ColorStateList)
* @see #setTrackColorInactive(ColorStateList)
* @see #setTrackColorActive(ColorStateList)
* @see #getTrackColorInactive()
* @see #getTrackColorActive()
* @attr ref com.google.android.material.R.styleable#Slider_trackColor
*/
@NonNull
public ColorStateList getTrackColor() {
if (!trackColorInactive.equals(trackColorActive)) {
throw new IllegalStateException(
"The inactive and active parts of the track are different colors. Use the"
+ " getInactiveTrackColor() and getActiveTrackColor() methods instead.");
}
return trackColorActive;
}
/**
* Sets the color of the track.
*
* @see #setTrackColorInactive(ColorStateList)
* @see #setTrackColorActive(ColorStateList)
* @see #getTrackColor()
* @attr ref com.google.android.material.R.styleable#Slider_trackColor
*/
public void setTrackColor(@NonNull ColorStateList trackColor) {
setTrackColorInactive(trackColor);
setTrackColorActive(trackColor);
}
/**
* Returns the color of the active portion of the track.
*
* @see #setTrackColorActive(ColorStateList)
* @see #setTrackColor(ColorStateList)
* @see #getTrackColor()
* @attr ref com.google.android.material.R.styleable#Slider_trackColorActive
*/
@NonNull
public ColorStateList getTrackColorActive() {
return trackColorActive;
}
/**
* Sets the color of the active portion of the track.
*
* @see #getTrackColorActive()
* @see #setTrackColor(ColorStateList)
* @attr ref com.google.android.material.R.styleable#Slider_trackColorActive
*/
public void setTrackColorActive(@NonNull ColorStateList trackColor) {
if (trackColor.equals(trackColorActive)) {
return;
}
trackColorActive = trackColor;
activeTrackPaint.setColor(getColorForState(trackColorActive));
invalidate();
}
/**
* Returns the color of the inactive portion of the track.
*
* @see #setTrackColorInactive(ColorStateList)
* @see #setTrackColor(ColorStateList)
* @see #getTrackColor()
* @attr ref com.google.android.material.R.styleable#Slider_trackColorInactive
*/
@NonNull
public ColorStateList getTrackColorInactive() {
return trackColorInactive;
}
/**
* Sets the color of the inactive portion of the track.
*
* @see #getTrackColorInactive()
* @see #setTrackColor(ColorStateList)
* @attr ref com.google.android.material.R.styleable#Slider_trackColorInactive
*/
public void setTrackColorInactive(@NonNull ColorStateList trackColor) {
if (trackColor.equals(trackColorInactive)) {
return;
}
trackColorInactive = trackColor;
inactiveTrackPaint.setColor(getColorForState(trackColorInactive));
invalidate();
}
@Override
public void setEnabled(boolean enabled) {
super.setEnabled(enabled);
// When we're disabled, set the layer type to hardware so we can clear the track out from behind
// the thumb.
setLayerType(enabled ? LAYER_TYPE_NONE : LAYER_TYPE_HARDWARE, null);
}
@Override
public void setOnFocusChangeListener(View.OnFocusChangeListener listener) {}
@Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
// The label is attached on the Overlay relative to the content.
label.setRelativeToView(ViewUtils.getContentView(this));
}
@Override
protected void onDetachedFromWindow() {
super.onDetachedFromWindow();
ViewUtils.getContentViewOverlay(this).remove(label);
label.detachView(ViewUtils.getContentView(this));
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(
widthMeasureSpec,
MeasureSpec.makeMeasureSpec(
widgetHeight + (labelBehavior == LABEL_WITHIN_BOUNDS ? label.getIntrinsicHeight() : 0),
MeasureSpec.EXACTLY));
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
updateTrackWidthAndTicksCoordinates(w);
updateHaloHotspot();
}
private void maybeUpdateTrackWidthAndTicksCoordinates() {
if (ViewCompat.isLaidOut(this)) {
// If we're already laid out we need to update the ticks.
updateTrackWidthAndTicksCoordinates(getWidth());
}
}
private void updateTrackWidthAndTicksCoordinates(int viewWidth) {
trackWidth = viewWidth - trackSidePadding * 2;
if (stepSize > 0.0f) {
int tickCount = (int) ((valueTo - valueFrom) / stepSize + 1);
if (ticksCoordinates == null || ticksCoordinates.length != tickCount * 2) {
ticksCoordinates = new float[tickCount * 2];
}
setTicksCoordinates(ticksCoordinates);
// Limit the tickCount if they will be too dense.
tickCount = Math.min(tickCount, trackWidth / (trackHeight * 2) + 1);
if (visibleTicksCoordinates == null || visibleTicksCoordinates.length != tickCount * 2) {
visibleTicksCoordinates = new float[tickCount * 2];
}
setTicksCoordinates(visibleTicksCoordinates);
}
}
private void setTicksCoordinates(float[] coordinates) {
int tickCount = coordinates.length / 2;
float interval = trackWidth / (float) (tickCount - 1);
for (int i = 0; i < tickCount * 2; i += 2) {
coordinates[i] = trackSidePadding + i / 2 * interval;
coordinates[i + 1] = calculateTop();
}
}
private void updateHaloHotspot() {
// Set the hotspot as the halo if RippleDrawable is being used.
if (!shouldDrawCompatHalo() && getMeasuredWidth() > 0) {
final Drawable background = getBackground();
if (background instanceof RippleDrawable) {
int x = (int) (thumbPosition * trackWidth + trackSidePadding);
int y = calculateTop();
DrawableCompat.setHotspotBounds(
background, x - haloRadius, y - haloRadius, x + haloRadius, y + haloRadius);
}
}
}
private int calculateTop() {
return trackTop + (labelBehavior == LABEL_WITHIN_BOUNDS ? label.getIntrinsicHeight() : 0);
}
@Override
protected void onDraw(@NonNull Canvas canvas) {
super.onDraw(canvas);
int top = calculateTop();
drawInactiveTrack(canvas, trackWidth, top);
if (thumbPosition > 0.0f) {
drawActiveTrack(canvas, trackWidth, top);
}
if (stepSize > 0.0f) {
drawTicks(canvas);
}
if ((thumbIsPressed || isFocused()) && isEnabled()) {
maybeDrawHalo(canvas, trackWidth, top);
}
drawThumb(canvas, trackWidth, top);
}
private void drawInactiveTrack(@NonNull Canvas canvas, int width, int top) {
float right = trackSidePadding + thumbPosition * width;
if (right < trackSidePadding + width) {
canvas.drawLine(right, top, trackSidePadding + width, top, inactiveTrackPaint);
}
}
private void drawActiveTrack(@NonNull Canvas canvas, int width, int top) {
float left = trackSidePadding + thumbPosition * width;
canvas.drawLine(trackSidePadding, top, left, top, activeTrackPaint);
}
private void drawTicks(@NonNull Canvas canvas) {
int pivotIndex = pivotIndex(visibleTicksCoordinates);
canvas.drawPoints(visibleTicksCoordinates, 0, pivotIndex * 2, activeTicksPaint);
canvas.drawPoints(
visibleTicksCoordinates,
pivotIndex * 2,
visibleTicksCoordinates.length - pivotIndex * 2,
inactiveTicksPaint);
}
private void drawThumb(@NonNull Canvas canvas, int width, int top) {
// Clear out the track behind the thumb if we're in a disable state since the thumb is
// transparent.
if (!isEnabled()) {
canvas.drawCircle(trackSidePadding + thumbPosition * width, top, thumbRadius, thumbPaint);
}
canvas.save();
canvas.translate(
trackSidePadding + (int) (thumbPosition * width) - thumbRadius, top - thumbRadius);
thumbDrawable.draw(canvas);
canvas.restore();
}
private void maybeDrawHalo(@NonNull Canvas canvas, int width, int top) {
// Only draw the halo for devices that aren't using the ripple.
if (shouldDrawCompatHalo()) {
int centerX = (int) (trackSidePadding + thumbPosition * width);
if (VERSION.SDK_INT < VERSION_CODES.P) {
// In this case we can clip the rect to allow drawing outside the bounds.
canvas.clipRect(
centerX - haloRadius,
top - haloRadius,
centerX + haloRadius,
top + haloRadius,
Op.UNION);
}
canvas.drawCircle(centerX, top, haloRadius, haloPaint);
}
}
private boolean shouldDrawCompatHalo() {
return forceDrawCompatHalo
|| VERSION.SDK_INT < VERSION_CODES.LOLLIPOP
|| !(getBackground() instanceof RippleDrawable);
}
@Override
public boolean onTouchEvent(@NonNull MotionEvent event) {
if (!isEnabled()) {
return false;
}
float x = event.getX();
float position = (x - trackSidePadding) / trackWidth;
position = Math.max(0, position);
position = Math.min(1, position);
switch (event.getActionMasked()) {
case MotionEvent.ACTION_DOWN:
// If we're inside a scrolling container,
// we should start dragging in ACTION_MOVE
if (isInScrollingContainer()) {
touchDownX = event.getX();
break;
}
getParent().requestDisallowInterceptTouchEvent(true);
requestFocus();
thumbIsPressed = true;
thumbPosition = position;
snapThumbPosition();
updateHaloHotspot();
ensureLabel();
updateLabelPosition();
invalidate();
onStartTrackingTouch();
dispatchOnChanged(true);
break;
case MotionEvent.ACTION_MOVE:
if (!thumbIsPressed) {
// Check if we're trying to scroll instead of dragging this Slider
if (Math.abs(x - touchDownX) < scaledTouchSlop) {
return false;
}
getParent().requestDisallowInterceptTouchEvent(true);
onStartTrackingTouch();
}
thumbIsPressed = true;
thumbPosition = position;
snapThumbPosition();
updateHaloHotspot();
ensureLabel();
updateLabelPosition();
invalidate();
dispatchOnChanged(true);
break;
case MotionEvent.ACTION_UP:
thumbIsPressed = false;
thumbPosition = position;
snapThumbPosition();
ViewUtils.getContentViewOverlay(this).remove(label);
onStopTrackingTouch();
invalidate();
break;
default:
// Nothing to do in this case.
}
// Set if the thumb is pressed. This will cause the ripple to be drawn.
setPressed(thumbIsPressed);
return true;
}
private void ensureLabel() {
float value = getValue();
if (hasLabelFormatter()) {
label.setText(formatter.getFormattedValue(value));
} else {
label.setText(String.format((int) value == value ? "%.0f" : "%.2f", value));
}
}
/** Calculates the index of the thumb for the given tick coordinates */
private int pivotIndex(float[] coordinates) {
return Math.round(thumbPosition * (coordinates.length / 2 - 1));
}
private void snapThumbPosition() {
if (stepSize > 0.0f) {
int intervalsCovered = pivotIndex(ticksCoordinates);
thumbPosition = (float) intervalsCovered / (ticksCoordinates.length / 2 - 1);
}
}
private void updateLabelPosition() {
if (labelBehavior == LABEL_GONE) {
// If the label shouldn't be drawn we can skip this.
return;
}
int left =
trackSidePadding + (int) (thumbPosition * trackWidth) - label.getIntrinsicWidth() / 2;
int top = calculateTop() - (labelPadding + thumbRadius);
label.setBounds(left, top - label.getIntrinsicHeight(), left + label.getIntrinsicWidth(), top);
// Calculate the difference between the bounds of this view and the bounds of the root view to
// correctly position this view in the overlay layer.
Rect rect = new Rect(label.getBounds());
DescendantOffsetUtils.offsetDescendantRect(ViewUtils.getContentView(this), this, rect);
label.setBounds(rect);
ViewUtils.getContentViewOverlay(this).add(label);
}
private void invalidateTrack() {
inactiveTrackPaint.setStrokeWidth(trackHeight);
activeTrackPaint.setStrokeWidth(trackHeight);
inactiveTicksPaint.setStrokeWidth(trackHeight / 2.0f);
activeTicksPaint.setStrokeWidth(trackHeight / 2.0f);
}
/**
* If this returns true, we can't start dragging the Slider immediately when we receive a {@link
* MotionEvent#ACTION_DOWN}. Instead, we must wait for a {@link MotionEvent#ACTION_MOVE}. Copied
* from hidden method of {@link View} isInScrollingContainer.
*
* @return true if any of this View's parents is a scrolling View.
*/
private boolean isInScrollingContainer() {
ViewParent p = getParent();
while (p instanceof ViewGroup) {
if (((ViewGroup) p).shouldDelayChildPressedState()) {
return true;
}
p = p.getParent();
}
return false;
}
private void dispatchOnChanged(boolean fromUser) {
final float value = getValue();
for (OnChangeListener listener : changeListeners) {
listener.onValueChange(this, value, fromUser);
}
}
private void onStartTrackingTouch() {
for (OnSliderTouchListener listener : touchListeners) {
listener.onStartTrackingTouch(this);
}
}
private void onStopTrackingTouch() {
for (OnSliderTouchListener listener : touchListeners) {
listener.onStopTrackingTouch(this);
}
}
@Override
protected void drawableStateChanged() {
super.drawableStateChanged();
inactiveTrackPaint.setColor(getColorForState(trackColorInactive));
activeTrackPaint.setColor(getColorForState(trackColorActive));
inactiveTicksPaint.setColor(getColorForState(tickColorInactive));
activeTicksPaint.setColor(getColorForState(tickColorActive));
if (label.isStateful()) {
label.setState(getDrawableState());
}
if (thumbDrawable.isStateful()) {
thumbDrawable.setState(getDrawableState());
}
haloPaint.setColor(getColorForState(haloColor));
haloPaint.setAlpha(HALO_ALPHA);
}
@ColorInt
private int getColorForState(@NonNull ColorStateList colorStateList) {
return colorStateList.getColorForState(getDrawableState(), colorStateList.getDefaultColor());
}
@VisibleForTesting
void forceDrawCompatHalo(boolean force) {
forceDrawCompatHalo = force;
}
@Override
protected Parcelable onSaveInstanceState() {
Parcelable superState = super.onSaveInstanceState();
SliderState sliderState = new SliderState(superState);
sliderState.valueFrom = valueFrom;
sliderState.valueTo = valueTo;
sliderState.thumbPosition = thumbPosition;
sliderState.stepSize = stepSize;
sliderState.hasFocus = hasFocus();
return sliderState;
}
@Override
protected void onRestoreInstanceState(Parcelable state) {
SliderState sliderState = (SliderState) state;
super.onRestoreInstanceState(sliderState.getSuperState());
valueFrom = sliderState.valueFrom;
valueTo = sliderState.valueTo;
thumbPosition = sliderState.thumbPosition;
stepSize = sliderState.stepSize;
if (sliderState.hasFocus) {
requestFocus();
}
dispatchOnChanged(false);
}
static class SliderState extends BaseSavedState {
float valueFrom;
float valueTo;
float thumbPosition;
float stepSize;
boolean hasFocus;
public static final Parcelable.Creator
*
*/
@IntDef({LABEL_FLOATING, LABEL_WITHIN_BOUNDS, LABEL_GONE})
@Retention(RetentionPolicy.SOURCE)
public @interface LabelBehavior {}
/** Interface definition for a callback invoked when a slider's value is changed. */
public interface OnChangeListener {
void onValueChange(@NonNull Slider slider, float value, boolean fromUser);
}
/**
* Interface definition for callbacks invoked when a slider's touch event is being
* started/stopped.
*/
public interface OnSliderTouchListener {
void onStartTrackingTouch(@NonNull Slider slider);
void onStopTrackingTouch(@NonNull Slider slider);
}
/**
* Interface definition for applying custom formatting to the text displayed inside the bubble
* shown when a slider is used in discrete mode.
*/
public interface LabelFormatter {
@NonNull
String getFormattedValue(float value);
}
/**
* A simple implementation of the {@link LabelFormatter} interface, that limits the number
* displayed inside a discrete slider's bubble to three digits, and a single-character suffix that
* denotes magnitude (e.g.: 1.5K, 2.2M, 1.3B, 2T).
*/
public static final class BasicLabelFormatter implements LabelFormatter {
private static final long TRILLION = 1000000000000L;
private static final int BILLION = 1000000000;
private static final int MILLION = 1000000;
private static final int THOUSAND = 1000;
@NonNull
@Override
public String getFormattedValue(float value) {
if (value >= TRILLION) {
return String.format(Locale.US, "%.1fT", value / TRILLION);
} else if (value >= BILLION) {
return String.format(Locale.US, "%.1fB", value / BILLION);
} else if (value >= MILLION) {
return String.format(Locale.US, "%.1fM", value / MILLION);
} else if (value >= THOUSAND) {
return String.format(Locale.US, "%.1fK", value / THOUSAND);
} else {
return String.format(Locale.US, "%.0f", value);
}
}
}
public Slider(@NonNull Context context) {
this(context, null);
}
public Slider(@NonNull Context context, @Nullable AttributeSet attrs) {
this(context, attrs, R.attr.sliderStyle);
}
public Slider(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
super(wrap(context, attrs, defStyleAttr, DEF_STYLE_RES), attrs, defStyleAttr);
// Ensure we are using the correctly themed context rather than the context that was passed in.
context = getContext();
inactiveTrackPaint = new Paint();
inactiveTrackPaint.setStyle(Style.STROKE);
inactiveTrackPaint.setStrokeCap(Cap.ROUND);
activeTrackPaint = new Paint();
activeTrackPaint.setStyle(Style.STROKE);
activeTrackPaint.setStrokeCap(Cap.ROUND);
thumbPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
thumbPaint.setStyle(Style.FILL);
thumbPaint.setXfermode(new PorterDuffXfermode(Mode.CLEAR));
haloPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
haloPaint.setStyle(Style.FILL);
inactiveTicksPaint = new Paint();
inactiveTicksPaint.setStyle(Style.STROKE);
inactiveTicksPaint.setStrokeCap(Cap.ROUND);
activeTicksPaint = new Paint();
activeTicksPaint.setStyle(Style.STROKE);
activeTicksPaint.setStrokeCap(Cap.ROUND);
loadResources(context.getResources());
processAttributes(context, attrs, defStyleAttr);
super.setOnFocusChangeListener(
new OnFocusChangeListener() {
@Override
public void onFocusChange(View v, boolean hasFocus) {
invalidate();
}
});
setFocusable(true);
// Set up the thumb drawable to always show the compat shadow.
thumbDrawable.setShadowCompatibilityMode(MaterialShapeDrawable.SHADOW_COMPAT_MODE_ALWAYS);
scaledTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop();
}
private void loadResources(@NonNull Resources resources) {
widgetHeight = resources.getDimensionPixelSize(R.dimen.mtrl_slider_widget_height);
trackSidePadding = resources.getDimensionPixelOffset(R.dimen.mtrl_slider_track_side_padding);
trackTop = resources.getDimensionPixelOffset(R.dimen.mtrl_slider_track_top);
labelPadding = resources.getDimensionPixelSize(R.dimen.mtrl_slider_label_padding);
}
private void processAttributes(Context context, AttributeSet attrs, int defStyleAttr) {
TypedArray a =
ThemeEnforcement.obtainStyledAttributes(
context, attrs, R.styleable.Slider, defStyleAttr, DEF_STYLE_RES);
valueFrom = a.getFloat(R.styleable.Slider_android_valueFrom, 0.0f);
valueTo = a.getFloat(R.styleable.Slider_android_valueTo, 1.0f);
setValue(a.getFloat(R.styleable.Slider_android_value, valueFrom));
stepSize = a.getFloat(R.styleable.Slider_android_stepSize, 0.0f);
boolean hasTrackColor = a.hasValue(R.styleable.Slider_trackColor);
int trackColorInactiveRes =
hasTrackColor ? R.styleable.Slider_trackColor : R.styleable.Slider_trackColorInactive;
int trackColorActiveRes =
hasTrackColor ? R.styleable.Slider_trackColor : R.styleable.Slider_trackColorActive;
ColorStateList trackColorInactive =
MaterialResources.getColorStateList(context, a, trackColorInactiveRes);
setTrackColorInactive(
trackColorInactive != null
? trackColorInactive
: AppCompatResources.getColorStateList(
context, R.color.material_slider_inactive_track_color));
ColorStateList trackColorActive =
MaterialResources.getColorStateList(context, a, trackColorActiveRes);
setTrackColorActive(
trackColorActive != null
? trackColorActive
: AppCompatResources.getColorStateList(
context, R.color.material_slider_active_track_color));
ColorStateList thumbColor =
MaterialResources.getColorStateList(context, a, R.styleable.Slider_thumbColor);
thumbDrawable.setFillColor(thumbColor);
ColorStateList haloColor =
MaterialResources.getColorStateList(context, a, R.styleable.Slider_haloColor);
setHaloColor(
haloColor != null
? haloColor
: AppCompatResources.getColorStateList(context, R.color.material_slider_halo_color));
boolean hasTickColor = a.hasValue(R.styleable.Slider_tickColor);
int tickColorInactiveRes =
hasTickColor ? R.styleable.Slider_tickColor : R.styleable.Slider_tickColorInactive;
int tickColorActiveRes =
hasTickColor ? R.styleable.Slider_tickColor : R.styleable.Slider_tickColorActive;
ColorStateList tickColorInactive =
MaterialResources.getColorStateList(context, a, tickColorInactiveRes);
setTickColorInactive(
tickColorInactive != null
? tickColorInactive
: AppCompatResources.getColorStateList(
context, R.color.material_slider_inactive_tick_marks_color));
ColorStateList tickColorActive =
MaterialResources.getColorStateList(context, a, tickColorActiveRes);
setTickColorActive(
tickColorActive != null
? tickColorActive
: AppCompatResources.getColorStateList(
context, R.color.material_slider_active_tick_marks_color));
label = parseLabelDrawable(context, a);
setThumbRadius(a.getDimensionPixelSize(R.styleable.Slider_thumbRadius, 0));
setHaloRadius(a.getDimensionPixelSize(R.styleable.Slider_haloRadius, 0));
setThumbElevation(a.getDimension(R.styleable.Slider_thumbElevation, 0));
setTrackHeight(a.getDimensionPixelSize(R.styleable.Slider_trackHeight, 0));
labelBehavior = a.getInt(R.styleable.Slider_labelBehavior, LABEL_FLOATING);
a.recycle();
validateValueFrom();
validateValueTo();
validateStepSize();
}
@NonNull
private TooltipDrawable parseLabelDrawable(@NonNull Context context, @NonNull TypedArray a) {
return TooltipDrawable.createFromAttributes(
context,
null,
0,
a.getResourceId(R.styleable.Slider_labelStyle, R.style.Widget_MaterialComponents_Tooltip));
}
private void validateValueFrom() {
if (valueFrom >= valueTo) {
Log.e(TAG, EXCEPTION_ILLEGAL_VALUE_FROM);
throw new IllegalArgumentException(EXCEPTION_ILLEGAL_VALUE_FROM);
}
}
private void validateValueTo() {
if (valueTo <= valueFrom) {
Log.e(TAG, EXCEPTION_ILLEGAL_VALUE_TO);
throw new IllegalArgumentException(EXCEPTION_ILLEGAL_VALUE_TO);
}
}
private void validateStepSize() {
if (stepSize < 0.0f) {
Log.e(TAG, EXCEPTION_ILLEGAL_STEP_SIZE);
throw new IllegalArgumentException(EXCEPTION_ILLEGAL_STEP_SIZE);
} else if (stepSize > 0.0f && ((valueTo - valueFrom) / stepSize) % 1 > THRESHOLD) {
Log.e(TAG, EXCEPTION_ILLEGAL_STEP_SIZE);
throw new IllegalArgumentException(EXCEPTION_ILLEGAL_STEP_SIZE);
}
}
/**
* Returns the slider's {@code valueFrom} value.
*
* @see #setValueFrom(float)
* @attr ref com.google.android.material.R.styleable#Slider_android_valueFrom
*/
public float getValueFrom() {
return valueFrom;
}
/**
* Sets the slider's {@code valueFrom} value.
*
*