Android 菜单箭头切换控件

  1 package com.example.drawablearrow;
  2 
  3 
  4 import android.content.Context;
  5 import android.graphics.Canvas;
  6 import android.graphics.ColorFilter;
  7 import android.graphics.Paint;
  8 import android.graphics.Path;
  9 import android.graphics.PixelFormat;
 10 import android.graphics.Rect;
 11 import android.graphics.drawable.Drawable;
 12 
 13 
 14 //这个类就是用来实现 菜单编程箭头效果的类
 15 public abstract class DrawerArrowDrawable extends Drawable {
 16     private static final float ARROW_HEAD_ANGLE = (float) Math.toRadians(45.0D); //箭头的角度
 17     protected float mBarGap;  //菜单 按钮两条线之间的间隔
 18     protected float mBarSize; //菜单 按钮线的长度
 19     protected float mBarThickness; //菜单按钮 线的宽度
 20     protected float mMiddleArrowSize; //箭头按钮 中间那条线的长度
 21     protected final Paint mPaint = new Paint();
 22     protected final Path mPath = new Path();
 23     protected float mProgress;
 24     protected int mSize;
 25     protected float mVerticalMirror = 1f;
 26     protected float mTopBottomArrowSize;//箭头 按钮的上下部分的长度
 27     protected Context context;
 28 
 29     public DrawerArrowDrawable(Context context) {
 30         this.context = context;
 31         this.mPaint.setAntiAlias(true);//设置抗锯齿
 32         this.mPaint.setColor(context.getResources().getColor(R.color.ldrawer_color)); //设置画笔的颜色为白色
 33         this.mSize = context.getResources().getDimensionPixelSize(R.dimen.ldrawer_drawableSize);
 34         this.mBarSize = context.getResources().getDimensionPixelSize(R.dimen.ldrawer_barSize);
 35         this.mTopBottomArrowSize = context.getResources().getDimensionPixelSize(R.dimen.ldrawer_topBottomBarArrowSize);
 36         this.mBarThickness = context.getResources().getDimensionPixelSize(R.dimen.ldrawer_thickness);
 37         this.mBarGap = context.getResources().getDimensionPixelSize(R.dimen.ldrawer_gapBetweenBars);
 38         this.mMiddleArrowSize = context.getResources().getDimensionPixelSize(R.dimen.ldrawer_middleBarArrowSize);
 39         this.mPaint.setStyle(Paint.Style.STROKE);
 40         //设置两条线相交时候 相交部分的处理
 41         this.mPaint.setStrokeJoin(Paint.Join.ROUND);
 42         this.mPaint.setStrokeCap(Paint.Cap.SQUARE);
 43         //设置画笔线的宽度
 44         this.mPaint.setStrokeWidth(this.mBarThickness);
 45     }
 46     //此方法是用来进行动画转换的时候差值的 第三个参数是进度
 47     protected float lerp(float paramFloat1, float paramFloat2, float paramFloat3) {
 48         return paramFloat1 + paramFloat3 * (paramFloat2 - paramFloat1);
 49     }
 50 
 51     public void draw(Canvas canvas) {
 52         Rect localRect = getBounds();
 53         float f1 = lerp(this.mBarSize, this.mTopBottomArrowSize, this.mProgress);
 54         float f2 = lerp(this.mBarSize, this.mMiddleArrowSize, this.mProgress);
 55         float f3 = lerp(0.0F, this.mBarThickness / 2.0F, this.mProgress);
 56         float f4 = lerp(0.0F, ARROW_HEAD_ANGLE, this.mProgress);
 57         float f5 = 0.0F;
 58         float f6 = 180.0F;
 59         float f7 = lerp(f5, f6, this.mProgress);
 60         float f8 = lerp(this.mBarGap + this.mBarThickness, 0.0F, this.mProgress);
 61         this.mPath.rewind();
 62         float f9 = -f2 / 2.0F;
 63         this.mPath.moveTo(f9 + f3, 0.0F);
 64         this.mPath.rLineTo(f2 - f3, 0.0F);
 65         float f10 = (float) Math.round(f1 * Math.cos(f4));
 66         float f11 = (float) Math.round(f1 * Math.sin(f4));
 67         this.mPath.moveTo(f9, f8);
 68         this.mPath.rLineTo(f10, f11);
 69         this.mPath.moveTo(f9, -f8);
 70         this.mPath.rLineTo(f10, -f11);
 71         this.mPath.moveTo(0.0F, 0.0F);
 72         this.mPath.close();
 73         canvas.save();
 74         if (!isLayoutRtl())
 75             canvas.rotate(180.0F, localRect.centerX(), localRect.centerY());
 76         canvas.rotate(f7 * mVerticalMirror, localRect.centerX(), localRect.centerY());
 77         canvas.translate(localRect.centerX(), localRect.centerY());
 78         canvas.drawPath(this.mPath, this.mPaint);
 79         canvas.restore();
 80     }
 81 
 82     public int getIntrinsicHeight() {
 83         return this.mSize;
 84     }
 85 
 86     public int getIntrinsicWidth() {
 87         return this.mSize;
 88     }
 89 
 90     public void setAlpha(int alpha) {
 91         this.mPaint.setAlpha(alpha);
 92     }
 93 
 94     @Override
 95     public int getOpacity() {
 96         return PixelFormat.TRANSLUCENT;
 97     }
 98 
 99     public abstract boolean isLayoutRtl();
100 
101     public void setColorFilter(ColorFilter colorFilter) {
102         this.mPaint.setColorFilter(colorFilter);
103     }
104 
105     public void setVerticalMirror(boolean mVerticalMirror) {
106         this.mVerticalMirror = mVerticalMirror ? 1 : -1;
107     }
108 
109     public void setProgress(float paramFloat) {
110         this.mProgress = paramFloat;
111         invalidateSelf();
112     }
113 
114     public void setColor(int resourceId) {
115         this.mPaint.setColor(context.getResources().getColor(resourceId));
116     }
117 }