Android自定义竖直方向SeekBar多色进度条

2019-12-12 04:58:59

字体：大中小

来源：转载

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写在前面

因为有这样的一个场景，需要实现竖直方向的多色进度条，然后在网上也找了下，没看到符合需要的，于是自定义了一个，效果如下：

具体实现

本来想定义水平的，然后旋转一下，后来发现还不如直接定义竖直方向来的直接，就直接在竖直方向画了下。

首先讲一下思路，就是通过继承View，然后通过onDraw()方法进行绘制。具体绘制的时候，需要处理一些小细节。

比如，我们需要画一个圆形的滑动块，那么我们的背景色带就不能把整个宽度占满，要不然，小圆块只能和色带一样宽了，效果不是很好看，所以在绘制的时候应该把背景画的宽度小于View的实际宽度。

接下来我要贴代码了：

 @Override protected void onDraw(Canvas canvas) {  super.onDraw(canvas);  int h = getMeasuredHeight();  int w = getMeasuredWidth();  mRadius = (float) w/2;  sLeft = w * 0.25f; // 背景左边缘坐标  sRight = w * 0.75f;// 背景右边缘坐标  sTop = 0;  sBottom = h;   sWidth = sRight - sLeft; // 背景宽度  sHeight = sBottom - sTop; // 背景高度  x = (float) w/2;//圆心的x坐标  y = (float) (1-0.01*progress)*sHeight;//圆心y坐标  drawBackground(canvas);  drawCircle(canvas);  paint.reset(); }

再看下画背景：

private void drawBackground(Canvas canvas){  RectF rectBlackBg = new RectF(sLeft, sTop, sRight, sBottom);  linearGradient=new LinearGradient(sLeft,sTop,sWidth,sHeight,colorArray,null, Shader.TileMode.MIRROR);  paint.setAntiAlias(true);  paint.setStyle(Paint.Style.FILL);  //设置渲染器  paint.setShader(linearGradient);  canvas.drawRoundRect(rectBlackBg, sWidth/2, sWidth/2, paint);}

这里使用LinearGradient实现多种颜色渐变，默认初始化定义如下:

 private int endColor=Color.WHITE; private int thumbColor=Color.BLACK; private int thumbBorderColor=Color.WHITE; private int colorArray[]={startColor, middleColor, endColor};

然后看下画圆的操作：

 private void drawCircle(Canvas canvas){  Paint thumbPaint = new Paint();  y = y < mRadius ? mRadius : y;//判断thumb边界  y = y > sHeight-mRadius ? sHeight-mRadius : y;  thumbPaint.setAntiAlias(true);  thumbPaint.setStyle(Paint.Style.FILL);  thumbPaint.setColor(thumbColor);  canvas.drawCircle(x, y, mRadius, thumbPaint);  thumbPaint.setStyle(Paint.Style.STROKE);  thumbPaint.setColor(thumbBorderColor);  thumbPaint.setStrokeWidth(2);  canvas.drawCircle(x, y, mRadius, thumbPaint); }

这里通过画布画了一个圆形，内部填充和外边沿。
上面的过程已经可以使效果展示出来了，但是无法操作，我们还需要给它加上事件才行：

 @Override public boolean onTouchEvent(MotionEvent event) {  this.y = event.getY();  progress= (sHeight-y)/sHeight*100;  switch(event.getAction()) {   case MotionEvent.ACTION_DOWN:    break;   case MotionEvent.ACTION_UP:    if (onStateChangeListener!=null){     onStateChangeListener.onStopTrackingTouch(this, progress);    }    break;   case MotionEvent.ACTION_MOVE:    if (onStateChangeListener!=null){     onStateChangeListener.OnStateChangeListener(this, progress);    }    setProgress(progress);    this.invalidate();    break;  }  return true; } public interface OnStateChangeListener{  void OnStateChangeListener(View view, float progress);  void onStopTrackingTouch(View view, float progress); } public void setOnStateChangeListener(OnStateChangeListener onStateChangeListener){  this.onStateChangeListener=onStateChangeListener; }

这里写了个回调接口，然后我们在Activity中就可以接收到相应的滑动进度，进而进行操作，当然，这里我们还得再加一个方法，以便改变seekbar的状态：

 public void setProgress(float progress) {  this.progress = progress;  invalidate(); }

到这里，功能基本就OK了，然后我们可以在Activity中去使用它了,下面是布局中的引用：

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:orientation="vertical"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:background="@color/bgColor" > <include layout="@layout/bar_simple_title" /> <LinearLayout  android:layout_width="match_parent"  android:layout_height="match_parent"  android:orientation="horizontal"  android:gravity="center"  >  <RelativeLayout   android:layout_marginTop="20dp"   android:layout_width="wrap_content"   android:layout_height="match_parent"   android:layout_marginRight="35dp"   >   <TextView    android:id="@+id/tv_inner_temper"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:text="@string/inner_temperature"    android:layout_centerHorizontal="true"    />   <com.tfxiaozi.widget.VerticalColorSeekBar    android:id="@+id/vpb_inner_temper"    android:layout_width="20dp"    android:layout_height="300dp"    android:layout_centerHorizontal="true"    android:layout_marginTop="30dp"/>   <TextView    android:id="@+id/tv_current_temper"    android:layout_below="@id/vpb_inner_temper"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:text="@string/current_temperature"    />  </RelativeLayout>  <RelativeLayout   android:layout_marginLeft="35dp"   android:layout_marginTop="20dp"   android:layout_width="wrap_content"   android:layout_height="match_parent"   >   <TextView    android:id="@+id/tv_brightness"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:text="@string/brightness"    android:layout_centerHorizontal="true"    />   <com.tfxiaozi.widget.VerticalColorSeekBar    android:id="@+id/vpb_brightness"    android:layout_width="20dp"    android:layout_height="300dp"    android:layout_centerHorizontal="true"    android:layout_marginTop="30dp"/>   <TextView    android:id="@+id/tv_current_brightness"    android:layout_below="@id/vpb_brightness"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_centerHorizontal="true"    android:text="0"    />  </RelativeLayout> </LinearLayout></LinearLayout>

怎么使用就很简单了：

package com.tfxiaozi.activity.setting;import android.graphics.Color;import android.os.Bundle;import android.view.View;import android.widget.ImageView;import android.widget.TextView;import com.tfxiaozi.R;import com.tfxiaozi.activity.BaseActivity;import com.tfxiaozi.utils.ToastUtils;import com.tfxiaozi.widget.VerticalColorSeekBar;/** * Created by dongqiang on 2016/10/16. */public class ManualSettingActivity extends BaseActivity implements View.OnClickListener, VerticalColorSeekBar.OnStateChangeListener { private TextView tvCurrentTemper, tvCurrentBrightness, tvMainTitle; private ImageView ivBack; private VerticalColorSeekBar vpbInnerTemper; private VerticalColorSeekBar vpbBrightness; @Override protected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.activity_manual_setting);  initViews();  initEvents();  initData(); } private void initViews() {  tvMainTitle = (TextView) findViewById(R.id.title_main_text);  tvMainTitle.setText(getString(R.string.manual_setting));  tvMainTitle.setVisibility(View.VISIBLE);  ivBack = (ImageView) findViewById(R.id.title_back);  ivBack.setVisibility(View.VISIBLE);  tvCurrentTemper = (TextView) findViewById(R.id.tv_current_temper);  tvCurrentBrightness = (TextView) findViewById(R.id.tv_current_brightness);  vpbInnerTemper = (VerticalColorSeekBar)findViewById(R.id.vpb_inner_temper);  vpbBrightness = (VerticalColorSeekBar) findViewById(R.id.vpb_brightness);  vpbInnerTemper.setColor(Color.RED, Color.YELLOW, Color.GREEN, Color.BLUE, Color.TRANSPARENT);  vpbBrightness.setColor(Color.BLUE, Color.WHITE, Color.YELLOW, Color.BLUE, Color.TRANSPARENT); } private void initEvents() {  ivBack.setOnClickListener(this);  vpbInnerTemper.setOnStateChangeListener(this);  vpbBrightness.setOnStateChangeListener(this); } private void initData() {  vpbInnerTemper.setProgress(50);  vpbBrightness.setProgress(70); } @Override public void onClick(View v) {  switch (v.getId()) {   case R.id.title_back:    finish();    break;  } } @Override public void OnStateChangeListener(View view, float progress) { } @Override public void onStopTrackingTouch(View view, float progress) {  int viewId = view.getId();  switch (viewId) {   case R.id.vpb_inner_temper:    if (progress < 0) {     progress = 0;    }    if(progress > 100) {     progress = 100;    }    ToastUtils.showShort(this, "progress= " + progress);    break;   case R.id.vpb_brightness:    if (progress < 0) {     progress = 0;    }    if(progress > 100) {     progress = 100;    }    ToastUtils.showShort(this, "progress1= " + progress);    break;  } }}

到这里就结束了，最后还是附上自定义View的整个代码吧：

package com.tfxiaozi.widget;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.LinearGradient;import android.graphics.Paint;import android.graphics.RectF;import android.graphics.Shader;import android.util.AttributeSet;import android.util.Log;import android.view.MotionEvent;import android.view.View;/** * Created by dongqiang on 2016/10/21. */public class VerticalColorSeekBar extends View{ private static final String TAG = VerticalColorSeekBar.class.getSimpleName(); private int startColor= Color.BLACK; private int middleColor = Color.GRAY; private int endColor=Color.WHITE; private int thumbColor=Color.BLACK; private int thumbBorderColor=Color.WHITE; private int colorArray[]={startColor, middleColor, endColor}; private float x,y; private float mRadius; private float progress; private float maxCount = 100f; private float sLeft, sTop, sRight, sBottom; private float sWidth,sHeight; private LinearGradient linearGradient; private Paint paint = new Paint(); protected OnStateChangeListener onStateChangeListener; public VerticalColorSeekBar(Context context) {  this(context, null); } public VerticalColorSeekBar(Context context, AttributeSet attrs) {  super(context, attrs); } @Override protected synchronized void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {  super.onMeasure(widthMeasureSpec, heightMeasureSpec);  setMeasuredDimension(getMeasuredWidth(), getMeasuredHeight()); } public void setColor(int startColor,int middleColor, int endColor,int thumbColor,int thumbBorderColor){  this.startColor= startColor;  this.middleColor = middleColor;  this.endColor= endColor;  this.thumbColor= thumbColor;  this.thumbBorderColor= thumbBorderColor;  colorArray[0] = startColor;  colorArray[1] = middleColor;  colorArray[2] = endColor; } @Override protected void onDraw(Canvas canvas) {  super.onDraw(canvas);  int h = getMeasuredHeight();  int w = getMeasuredWidth();  mRadius = (float) w/2;  sLeft = w * 0.25f; // 背景左边缘坐标  sRight = w * 0.75f;// 背景右边缘坐标  sTop = 0;   sBottom = h;   sWidth = sRight - sLeft; // 背景宽度  sHeight = sBottom - sTop; // 背景高度  x = (float) w/2;//圆心的x坐标  y = (float) (1-0.01*progress)*sHeight;//圆心y坐标  drawBackground(canvas);  drawCircle(canvas);  paint.reset(); } private void drawBackground(Canvas canvas){  RectF rectBlackBg = new RectF(sLeft, sTop, sRight, sBottom);  linearGradient=new LinearGradient(sLeft,sTop,sWidth,sHeight,colorArray,null, Shader.TileMode.MIRROR);  paint.setAntiAlias(true);  paint.setStyle(Paint.Style.FILL);  //设置渲染器  paint.setShader(linearGradient);  canvas.drawRoundRect(rectBlackBg, sWidth/2, sWidth/2, paint); } private void drawCircle(Canvas canvas){  Paint thumbPaint = new Paint();  y = y < mRadius ? mRadius : y;//判断thumb边界  y = y > sHeight-mRadius ? sHeight-mRadius : y;  thumbPaint.setAntiAlias(true);  thumbPaint.setStyle(Paint.Style.FILL);  thumbPaint.setColor(thumbColor);  canvas.drawCircle(x, y, mRadius, thumbPaint);  thumbPaint.setStyle(Paint.Style.STROKE);  thumbPaint.setColor(thumbBorderColor);  thumbPaint.setStrokeWidth(2);  canvas.drawCircle(x, y, mRadius, thumbPaint); } @Override public boolean onTouchEvent(MotionEvent event) {  this.y = event.getY();  progress= (sHeight-y)/sHeight*100;  switch(event.getAction()) {   case MotionEvent.ACTION_DOWN:    break;   case MotionEvent.ACTION_UP:    if (onStateChangeListener!=null){     onStateChangeListener.onStopTrackingTouch(this, progress);    }    break;   case MotionEvent.ACTION_MOVE:    if (onStateChangeListener!=null){     onStateChangeListener.OnStateChangeListener(this, progress);    }    setProgress(progress);    this.invalidate();    break;  }  return true; } public interface OnStateChangeListener{  void OnStateChangeListener(View view, float progress);  void onStopTrackingTouch(View view, float progress); } public void setOnStateChangeListener(OnStateChangeListener onStateChangeListener){  this.onStateChangeListener=onStateChangeListener; } public void setProgress(float progress) {  this.progress = progress;  invalidate(); }}

结束

到这里就真的结束啦，就当记录一下吧，然后也希望帮到有需要的人。有更好的实现也可以告诉我哈~

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持武林网。

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