Android 自定义SeekBar显示进度百分比
效果图： 
代码实现：
package com.tchip.autosetting.view;
import com.nineoldandroids.view.ViewHelper;
import com.tchip.autosetting.R;
import android.app.Dialog;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.drawable.GradientDrawable;
import android.graphics.drawable.LayerDrawable;
import android.os.Bundle;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.MotionEvent;
import android.view.View;
import android.view.Window;
import android.widget.RelativeLayout;
import android.widget.TextView;
public class Slider extends CustomView {
// Event when slider change value
public interface OnValueChangedListener {
public void onValueChanged(int value);
}
int backgroundColor = Color.parseColor("#4CAF50");
Ball ball;
NumberIndicator numberIndicator;
boolean showNumberIndicator = false;
boolean press = false;
int value = 0;
int max = 100;
int min = 0;
OnValueChangedListener onValueChangedListener;
public Slider(Context context, AttributeSet attrs) {
super(context, attrs);
setAttributes(attrs);
}
// Set atributtes of XML to View
protected void setAttributes(AttributeSet attrs) {
setBackgroundResource(R.drawable.background_transparent);
// Set size of view
setMinimumHeight(Utils.dpToPx(48, getResources()));
setMinimumWidth(Utils.dpToPx(80, getResources()));
// Set background Color
// Color by resource
int bacgroundColor = attrs.getAttributeResourceValue(ANDROIDXML,
"background", -1);
if (bacgroundColor != -1) {
setBackgroundColor(getResources().getColor(bacgroundColor));
} else {
// Color by hexadecimal
int background = attrs.getAttributeIntValue(ANDROIDXML,
"background", -1);
if (background != -1)
setBackgroundColor(background);
}
showNumberIndicator = attrs.getAttributeBooleanValue(MATERIALDESIGNXML,
"showNumberIndicator", false);
min = attrs.getAttributeIntValue(MATERIALDESIGNXML, "min", 0);
max = attrs.getAttributeIntValue(MATERIALDESIGNXML, "max", 0);
value = attrs.getAttributeIntValue(MATERIALDESIGNXML, "value", min);
ball = new Ball(getContext());
RelativeLayout.LayoutParams params = new LayoutParams(Utils.dpToPx(20,
getResources()), Utils.dpToPx(20, getResources()));
params.addRule(RelativeLayout.CENTER_VERTICAL, RelativeLayout.TRUE);
ball.setLayoutParams(params);
addView(ball);
// Set if slider content number indicator
// TODO
if (showNumberIndicator) {
numberIndicator = new NumberIndicator(getContext());
}
}
@Override
public void invalidate() {
ball.invalidate();
super.invalidate();
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (!placedBall)
placeBall();
if (value == min) {
// Crop line to transparent effect
Bitmap bitmap = Bitmap.createBitmap(canvas.getWidth(),
canvas.getHeight(), Bitmap.Config.ARGB_8888);
Canvas temp = new Canvas(bitmap);
Paint paint = new Paint();
paint.setColor(Color.parseColor("#B0B0B0"));
paint.setStrokeWidth(Utils.dpToPx(2, getResources()));
temp.drawLine(getHeight() / 2, getHeight() / 2, getWidth()
- getHeight() / 2, getHeight() / 2, paint);
Paint transparentPaint = new Paint();
transparentPaint.setColor(getResources().getColor(
android.R.color.transparent));
transparentPaint.setXfermode(new PorterDuffXfermode(
PorterDuff.Mode.CLEAR));
temp.drawCircle(ViewHelper.getX(ball) + ball.getWidth() / 2,
ViewHelper.getY(ball) + ball.getHeight() / 2,
ball.getWidth() / 2, transparentPaint);
canvas.drawBitmap(bitmap, 0, 0, new Paint());
} else {
Paint paint = new Paint();
paint.setColor(Color.parseColor("#B0B0B0"));
paint.setStrokeWidth(Utils.dpToPx(2, getResources()));
canvas.drawLine(getHeight() / 2, getHeight() / 2, getWidth()
- getHeight() / 2, getHeight() / 2, paint);
paint.setColor(backgroundColor);
float division = (ball.xFin - ball.xIni) / (max - min);
int value = this.value - min;
canvas.drawLine(getHeight() / 2, getHeight() / 2, value * division
+ getHeight() / 2, getHeight() / 2, paint);
}
if (press && !showNumberIndicator) {
Paint paint = new Paint();
paint.setColor(backgroundColor);
paint.setAntiAlias(true);
canvas.drawCircle(ViewHelper.getX(ball) + ball.getWidth() / 2,
getHeight() / 2, getHeight() / 3, paint);
}
invalidate();
}
@Override
public boolean onTouchEvent(MotionEvent event) {
isLastTouch = true;
if (isEnabled()) {
if (event.getAction() == MotionEvent.ACTION_DOWN
|| event.getAction() == MotionEvent.ACTION_MOVE) {
if (numberIndicator != null
&& numberIndicator.isShowing() == false)
numberIndicator.show();
if ((event.getX() <= getWidth() && event.getX() >= 0)) {
press = true;
// calculate value
int newValue = 0;
float division = (ball.xFin - ball.xIni) / (max - min);
if (event.getX() > ball.xFin) {
newValue = max;
} else if (event.getX() < ball.xIni) {
newValue = min;
} else {
newValue = min
+ (int) ((event.getX() - ball.xIni) / division);
}
if (value != newValue) {
value = newValue;
if (onValueChangedListener != null)
onValueChangedListener.onValueChanged(newValue);
}
// move ball indicator
float x = event.getX();
x = (x < ball.xIni) ? ball.xIni : x;
x = (x > ball.xFin) ? ball.xFin : x;
ViewHelper.setX(ball, x);
ball.changeBackground();
// If slider has number indicator
if (numberIndicator != null) {
// move number indicator
numberIndicator.indicator.x = x;
numberIndicator.indicator.finalY = Utils
.getRelativeTop(this) - getHeight() / 2;
numberIndicator.indicator.finalSize = getHeight() / 2;
numberIndicator.numberIndicator.setText("");
}
} else {
press = false;
isLastTouch = false;
if (numberIndicator != null)
numberIndicator.dismiss();
}
} else if (event.getAction() == MotionEvent.ACTION_UP
|| event.getAction() == MotionEvent.ACTION_CANCEL) {
if (numberIndicator != null)
numberIndicator.dismiss();
isLastTouch = false;
press = false;
}
}
return true;
}
/**
* Make a dark color to press effect
*
* @return
*/
protected int makePressColor() {
int r = (this.backgroundColor >> 16) & 0xFF;
int g = (this.backgroundColor >> 8) & 0xFF;
int b = (this.backgroundColor >> 0) & 0xFF;
r = (r - 30 < 0) ? 0 : r - 30;
g = (g - 30 < 0) ? 0 : g - 30;
b = (b - 30 < 0) ? 0 : b - 30;
return Color.argb(70, r, g, b);
}
private void placeBall() {
ViewHelper.setX(ball, getHeight() / 2 - ball.getWidth() / 2);
ball.xIni = ViewHelper.getX(ball);
ball.xFin = getWidth() - getHeight() / 2 - ball.getWidth() / 2;
ball.xCen = getWidth() / 2 - ball.getWidth() / 2;
placedBall = true;
}
// GETERS & SETTERS
public OnValueChangedListener getOnValueChangedListener() {
return onValueChangedListener;
}
public void setOnValueChangedListener(
OnValueChangedListener onValueChangedListener) {
this.onValueChangedListener = onValueChangedListener;
}
public int getValue() {
return value;
}
public void setValue(final int value) {
if (placedBall == false)
post(new Runnable() {
@Override
public void run() {
setValue(value);
}
});
else {
this.value = value;
float division = (ball.xFin - ball.xIni) / max;
ViewHelper.setX(ball,
value * division + getHeight() / 2 - ball.getWidth() / 2);
ball.changeBackground();
}
}
public int getMax() {
return max;
}
public void setMax(int max) {
this.max = max;
}
public int getMin() {
return min;
}
public void setMin(int min) {
this.min = min;
}
public boolean isShowNumberIndicator() {
return showNumberIndicator;
}
public void setShowNumberIndicator(boolean showNumberIndicator) {
this.showNumberIndicator = showNumberIndicator;
numberIndicator = (showNumberIndicator) ? new NumberIndicator(
getContext()) : null;
}
@Override
public void setBackgroundColor(int color) {
backgroundColor = color;
if (isEnabled())
beforeBackground = backgroundColor;
}
boolean placedBall = false;
class Ball extends View {
float xIni, xFin, xCen;
public Ball(Context context) {
super(context);
setBackgroundResource(R.drawable.background_switch_ball_uncheck);
}
public void changeBackground() {
if (value != min) {
setBackgroundResource(R.drawable.background_checkbox);
LayerDrawable layer = (LayerDrawable) getBackground();
GradientDrawable shape = (GradientDrawable) layer
.findDrawableByLayerId(R.id.shape_bacground);
shape.setColor(backgroundColor);
} else {
setBackgroundResource(R.drawable.background_switch_ball_uncheck);
}
}
}
// Slider Number Indicator
class NumberIndicator extends Dialog {
Indicator indicator;
TextView numberIndicator;
public NumberIndicator(Context context) {
super(context, android.R.style.Theme_Translucent);
}
@Override
protected void onCreate(Bundle savedInstanceState) {
requestWindowFeature(Window.FEATURE_NO_TITLE);
super.onCreate(savedInstanceState);
setContentView(R.layout.number_indicator_spinner);
setCanceledOnTouchOutside(false);
RelativeLayout content = (RelativeLayout) this
.findViewById(R.id.number_indicator_spinner_content);
indicator = new Indicator(this.getContext());
content.addView(indicator);
numberIndicator = new TextView(getContext());
numberIndicator.setTextColor(Color.WHITE);
numberIndicator.setGravity(Gravity.CENTER);
content.addView(numberIndicator);
indicator.setLayoutParams(new RelativeLayout.LayoutParams(
RelativeLayout.LayoutParams.FILL_PARENT,
RelativeLayout.LayoutParams.FILL_PARENT));
}
@Override
public void dismiss() {
super.dismiss();
indicator.y = 0;
indicator.size = 0;
indicator.animate = true;
}
@Override
public void onBackPressed() {
}
}
class Indicator extends RelativeLayout {
// Position of number indicator
float x = 0;
float y = 0;
// Size of number indicator
float size = 0;
// Final y position after animation
float finalY = 0;
// Final size after animation
float finalSize = 0;
boolean animate = true;
boolean numberIndicatorResize = false;
public Indicator(Context context) {
super(context);
setBackgroundColor(getResources().getColor(
android.R.color.transparent));
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (numberIndicatorResize == false) {
LayoutParams params = (LayoutParams) numberIndicator.numberIndicator
.getLayoutParams();
params.height = (int) finalSize * 2;
params.width = (int) finalSize * 2;
numberIndicator.numberIndicator.setLayoutParams(params);
}
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setColor(backgroundColor);
if (animate) {
if (y == 0)
y = finalY + finalSize * 2;
y -= Utils.dpToPx(6, getResources());
size += Utils.dpToPx(2, getResources());
}
canvas.drawCircle(
ViewHelper.getX(ball)
+ Utils.getRelativeLeft((View) ball.getParent())
+ ball.getWidth() / 2, y, size, paint);
if (animate && size >= finalSize)
animate = false;
if (animate == false) {
ViewHelper
.setX(numberIndicator.numberIndicator,
(ViewHelper.getX(ball)
+ Utils.getRelativeLeft((View) ball
.getParent()) + ball.getWidth() / 2)
- size);
ViewHelper.setY(numberIndicator.numberIndicator, y - size);
numberIndicator.numberIndicator
.setText((int) (value * 100 / max) + "%");
}
invalidate();
}
}
}