Android自定义View实现炫酷进度条

本文实例为大家分享了Android实现炫酷进度条的具体代码，供大家参考，具体内容如下

下面我们来实现如下效果：

第一步：创建attrs文件夹，自定义属性：

<?xml version="1.0" encoding="utf-8"?>
<resources>
  <declare-styleable name="MyProgress">
    <attr name="out_color" format="color"/>
    <attr name="inner_color" format="color"/>
    <attr name="border_width" format="dimension"/>
    <attr name="text_color" format="color"/>
    <attr name="text_size" format="dimension"/>
  </declare-styleable>
</resources>

第二步：自定义View：

/**
 * Created by Michael on 2019/11/1.
 */

public class MyProgress extends View {

  private int outColor;
  private int innerColor;
  private int textColor;
  private float borderWidth;
  private int textSize;
  private Paint mOutPaint;
  private Paint mInnerPaint;
  private Paint mTextPaint;
  private float percent;
  private int p;

  public MyProgress(Context context) {
    this(context,null);
  }

  public MyProgress(Context context, @Nullable AttributeSet attrs) {
    this(context, attrs,0);
  }

  public MyProgress(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
    TypedArray array = context.obtainStyledAttributes(attrs,R.styleable.MyProgress);
    outColor = array.getColor(R.styleable.MyProgress_out_color, Color.GREEN);
    innerColor = array.getColor(R.styleable.MyProgress_inner_color, Color.BLUE);
    textColor = array.getColor(R.styleable.MyProgress_text_color, Color.BLACK);
    borderWidth = array.getDimension(R.styleable.MyProgress_border_width,10);
    textSize = array.getDimensionPixelSize(R.styleable.MyProgress_text_size,20);
    array.recycle();
    init();

  }

  private void init() {
    mOutPaint = new Paint();
    mOutPaint.setAntiAlias(true);
    mOutPaint.setDither(true);
    mOutPaint.setStyle(Paint.Style.STROKE);
    mOutPaint.setStrokeWidth(borderWidth);
    mOutPaint.setColor(outColor);

    mInnerPaint = new Paint();
    mInnerPaint.setAntiAlias(true);
    mInnerPaint.setDither(true);
    mInnerPaint.setStyle(Paint.Style.STROKE);
    mInnerPaint.setStrokeWidth(borderWidth);
    mInnerPaint.setColor(innerColor);

    mTextPaint = new Paint();
    mTextPaint.setAntiAlias(true);
    mTextPaint.setDither(true);
    mTextPaint.setStyle(Paint.Style.FILL);
    mTextPaint.setTextSize(textSize);
    mTextPaint.setColor(textColor);

    percent = 0;
    p = 100;
  }

  @Override
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    int widthMode = MeasureSpec.getMode(widthMeasureSpec);
    int heightMode = MeasureSpec.getMode(heightMeasureSpec);
    int width = 0,height =0;
    if (widthMode == MeasureSpec.AT_MOST){

    }else{
      width = MeasureSpec.getSize(widthMeasureSpec);
    }
    if (heightMode == MeasureSpec.AT_MOST){

    }else{
      height = MeasureSpec.getSize(heightMeasureSpec);
    }
    setMeasuredDimension(width>height?height:width,width>height?height:width);
  }

  @Override
  protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    int rWidth = getWidth()>getHeight()?getHeight():getWidth();
    int rHeight = getWidth()>getHeight()?getHeight():getWidth();
    //int rWidth = getWidth();
    //int rHeight = getHeight();

    float radius = rWidth/2 - borderWidth/2;
    canvas.drawCircle(rWidth/2,rHeight/2,radius,mOutPaint);

    RectF r = new RectF(borderWidth/2,borderWidth/2,
        rWidth-borderWidth/2,rHeight-borderWidth/2);
    canvas.drawArc(r,0,360*percent,false,mInnerPaint);

    String s1 = (int)(percent*100) + "%";
    Rect r2 = new Rect();
    mTextPaint.getTextBounds(s1,0,s1.length(),r2);
    int tWidth = r2.width();
    int tHeight = r2.height();
    Paint.FontMetricsInt fontMetricsInt = new Paint.FontMetricsInt();
    int dy = (fontMetricsInt.bottom-fontMetricsInt.top)/2-fontMetricsInt.bottom;
    int baseLine = tHeight/2+dy+rHeight/2-tHeight/2;
    int x0 = rWidth/2-tWidth/2;
    canvas.drawText(s1,x0,baseLine,mTextPaint);
  }

  public void setProgress(float percent,int value){
    this.percent = percent;
    invalidate();
  }

}

然后在布局中使用：

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:app="http://schemas.android.com/apk/res-auto"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  tools:context="com.example.michael.view_02.MainActivity">

  <com.example.michael.view_02.MyProgress
    android:id="@+id/progress"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:out_color="@color/colorPrimary"
    app:inner_color="@color/colorAccent"
    app:text_color="@color/colorPrimaryDark"
    app:border_width="10dp"
    app:text_size="20sp"
    />

</android.support.constraint.ConstraintLayout>

在activity中使用属性动画完成效果：

public class MainActivity extends AppCompatActivity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    final MyProgress progress = findViewById(R.id.progress);
    ValueAnimator animator = ValueAnimator.ofInt(0,5000);
    animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
      @Override
      public void onAnimationUpdate(ValueAnimator animation) {
        float p = animation.getAnimatedFraction();
        int value = (int)animation.getAnimatedValue();
        progress.setProgress(p,value);
      }
    });
    animator.setDuration(10000);
    animator.start();
  }

}

如果我们改动一下代码：

//int rWidth = getWidth();
//int rHeight = getHeight();

我们使用onDraw()方法的时候如果使用上面的方法确定宽高，将会绘制成下图所示：

很奇怪！欢迎大家解决此问题。

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我们。