Android特效专辑(五)——自定义圆形头像和仿MIUI卸载动画—粒子爆炸

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好的，各位亲爱的朋友，今天讲的特效还是比较炫的，首先，我们会讲一个自定义圆形的imageView，接着，我们会来实现粒子爆炸的特效，按照国际惯例，无图无真相的没这个效果也是模仿大神的，现在应用在了我的《Only》上

截图

好的，我们新建一个工程——AnimView，我们要用到的图片

一.自定义圆形头像——

直接开写了，要实现的东西都在注释上了

1.编写自定义属性attr.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <declare-styleable name="roundedimageview">

        <attr name="border_thickness" format="dimension" />

        <attr name="border_inside_color" format="color" />

        <attr name="border_outside_color" format="color"></attr>

    </declare-styleable>
</resources>

2.自定义View

紧接着我们就可以编写这个类了

package com.lgl.animview;

/**
 * 圆形头像
 * Created by LGL on 2016/1/12.
 */

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.NinePatchDrawable;
import android.util.AttributeSet;
import android.widget.ImageView;

/**
 * 圆形ImageView，可设置最多两个宽度不同且颜色不同的圆形边框。 设置颜色在xml布局文件中由自定义属性配置参数指定
 */

public class RoundImageView extends ImageView {

    private int mBorderThickness = 0;

    private Context mContext;

    private int defaultColor = 0xFFFFFFFF;

    // 如果只有其中一个有值，则只画一个圆形边框

    private int mBorderOutsideColor = 0;

    private int mBorderInsideColor = 0;

    // 控件默认长、宽

    private int defaultWidth = 0;

    private int defaultHeight = 0;

    public RoundImageView(Context context) {

        super(context);

        mContext = context;

    }

    public RoundImageView(Context context, AttributeSet attrs) {

        super(context, attrs);

        mContext = context;

        setCustomAttributes(attrs);

    }

    public RoundImageView(Context context, AttributeSet attrs, int defStyle) {

        super(context, attrs, defStyle);

        mContext = context;

        setCustomAttributes(attrs);

    }

    private void setCustomAttributes(AttributeSet attrs) {

        // 获取自定义的属性
        TypedArray a = mContext.obtainStyledAttributes(attrs,
                R.styleable.roundedimageview);

        mBorderThickness = a.getDimensionPixelSize(
                R.styleable.roundedimageview_border_thickness, 0);

        mBorderOutsideColor = a
                .getColor(R.styleable.roundedimageview_border_outside_color,
                        defaultColor);

        mBorderInsideColor = a.getColor(
                R.styleable.roundedimageview_border_inside_color, defaultColor);

    }

    @Override
    protected void onDraw(Canvas canvas) {

        Drawable drawable = getDrawable();

        if (drawable == null) {

            return;

        }

        if (getWidth() == 0 || getHeight() == 0) {

            return;

        }

        this.measure(0, 0);

        if (drawable.getClass() == NinePatchDrawable.class)

            return;

        Bitmap b = ((BitmapDrawable) drawable).getBitmap();

        Bitmap bitmap = b.copy(Bitmap.Config.ARGB_8888, true);

        if (defaultWidth == 0) {

            defaultWidth = getWidth();

        }

        if (defaultHeight == 0) {

            defaultHeight = getHeight();

        }

        int radius = 0;

        if (mBorderInsideColor != defaultColor
                && mBorderOutsideColor != defaultColor) {// 定义画两个边框，分别为外圆边框和内圆边框

            radius = (defaultWidth < defaultHeight ? defaultWidth
                    : defaultHeight) / 2 - 2 * mBorderThickness;

            // 画内圆

            drawCircleBorder(canvas, radius + mBorderThickness / 2,
                    mBorderInsideColor);

            // 画外圆

            drawCircleBorder(canvas, radius + mBorderThickness
                    + mBorderThickness / 2, mBorderOutsideColor);

        } else if (mBorderInsideColor != defaultColor
                && mBorderOutsideColor == defaultColor) {// 定义画一个边框

            radius = (defaultWidth < defaultHeight ? defaultWidth
                    : defaultHeight) / 2 - mBorderThickness;

            drawCircleBorder(canvas, radius + mBorderThickness / 2,
                    mBorderInsideColor);

        } else if (mBorderInsideColor == defaultColor
                && mBorderOutsideColor != defaultColor) {// 定义画一个边框

            radius = (defaultWidth < defaultHeight ? defaultWidth
                    : defaultHeight) / 2 - mBorderThickness;

            drawCircleBorder(canvas, radius + mBorderThickness / 2,
                    mBorderOutsideColor);

        } else {// 没有边框

            radius = (defaultWidth < defaultHeight ? defaultWidth
                    : defaultHeight) / 2;

        }

        Bitmap roundBitmap = getCroppedRoundBitmap(bitmap, radius);

        canvas.drawBitmap(roundBitmap, defaultWidth / 2 - radius, defaultHeight
                / 2 - radius, null);

    }

    /**
     * 获取裁剪后的圆形图片
     */

    public Bitmap getCroppedRoundBitmap(Bitmap bmp, int radius) {

        Bitmap scaledSrcBmp;

        int diameter = radius * 2;

        // 为了防止宽高不相等，造成圆形图片变形，因此截取长方形中处于中间位置最大的正方形图片

        int bmpWidth = bmp.getWidth();

        int bmpHeight = bmp.getHeight();

        int squareWidth = 0, squareHeight = 0;

        int x = 0, y = 0;

        Bitmap squareBitmap;

        if (bmpHeight > bmpWidth) {// 高大于宽

            squareWidth = squareHeight = bmpWidth;

            x = 0;

            y = (bmpHeight - bmpWidth) / 2;

            // 截取正方形图片

            squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth,
                    squareHeight);

        } else if (bmpHeight < bmpWidth) {// 宽大于高

            squareWidth = squareHeight = bmpHeight;

            x = (bmpWidth - bmpHeight) / 2;

            y = 0;

            squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth,
                    squareHeight);

        } else {

            squareBitmap = bmp;

        }

        if (squareBitmap.getWidth() != diameter
                || squareBitmap.getHeight() != diameter) {

            scaledSrcBmp = Bitmap.createScaledBitmap(squareBitmap, diameter,
                    diameter, true);

        } else {

            scaledSrcBmp = squareBitmap;

        }

        Bitmap output = Bitmap.createBitmap(scaledSrcBmp.getWidth(),

        scaledSrcBmp.getHeight(),

        Bitmap.Config.ARGB_8888);

        Canvas canvas = new Canvas(output);

        Paint paint = new Paint();

        Rect rect = new Rect(0, 0, scaledSrcBmp.getWidth(),
                scaledSrcBmp.getHeight());

        paint.setAntiAlias(true);

        paint.setFilterBitmap(true);

        paint.setDither(true);

        canvas.drawARGB(0, 0, 0, 0);

        canvas.drawCircle(scaledSrcBmp.getWidth() / 2,

        scaledSrcBmp.getHeight() / 2,

        scaledSrcBmp.getWidth() / 2,

        paint);

        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));

        canvas.drawBitmap(scaledSrcBmp, rect, rect, paint);

        bmp = null;

        squareBitmap = null;

        scaledSrcBmp = null;

        return output;

    }

    /**
     * 边缘画圆
     */

    private void drawCircleBorder(Canvas canvas, int radius, int color) {

        Paint paint = new Paint();

        /* 去锯齿 */

        paint.setAntiAlias(true);

        paint.setFilterBitmap(true);

        paint.setDither(true);

        paint.setColor(color);

        /* 设置paint的　style　为STROKE：空心 */

        paint.setStyle(Paint.Style.STROKE);

        /* 设置paint的外框宽度 */

        paint.setStrokeWidth(mBorderThickness);

        canvas.drawCircle(defaultWidth / 2, defaultHeight / 2, radius, paint);

    }

}

3.引用

引用起来就比较简单了，我们首先来引入他的命名空间

 xmlns:imagecontrol="http://schemas.android.com/apk/res-auto"

然后我们直接写xml

  <com.lgl.animview.RoundImageView
        android:id="@+id/iv_round"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/photo"
        imagecontrol:border_inside_color="#bc0978"
        imagecontrol:border_outside_color="#ba3456"
        imagecontrol:border_thickness="1dp" />

好的，让我们运行下吧

二.MUI卸载动画——粒子爆炸

关于这个粒子特效，在开篇的时候已经展示了效果，那么我们接下来，要怎么做尼？

1.ParticleUtils

用于粒子动画的单位转换

package com.lgl.animview;

import android.content.res.Resources;

/**
 * 粒子动画
 */
public class ParticleUtils {
    /**
     * 密度
     */
    public static final float DENSITY = Resources.getSystem().getDisplayMetrics().density;

    public static int dp2px(int dp) {
        return Math.round(dp * DENSITY);
    }
}

2.Particle

用于爆破效果的分子计算

package com.lgl.animview;

import java.util.Random;

import android.graphics.Point;
import android.graphics.Rect;

/**
 * Created by lgl on 16/01/14. 爆破粒子
 */
public class Particle {

    public static final int PART_WH = 8; // 默认小球宽高

    // 原本的值（不可变）
    // float originCX;
    // float originCY;
    // float originRadius;

    // 实际的值（可变）
    float cx; // center x of circle
    float cy; // center y of circle
    float radius;

    int color;
    float alpha;

    static Random random = new Random();

    Rect mBound;

    public static Particle generateParticle(int color, Rect bound, Point point) {
        int row = point.y; // 行是高
        int column = point.x; // 列是宽

        Particle particle = new Particle();
        particle.mBound = bound;
        particle.color = color;
        particle.alpha = 1f;

        particle.radius = PART_WH;
        particle.cx = bound.left + PART_WH * column;
        particle.cy = bound.top + PART_WH * row;

        return particle;
    }

    public void advance(float factor) {
        cx = cx + factor * random.nextInt(mBound.width())
                * (random.nextFloat() - 0.5f);
        cy = cy + factor * random.nextInt(mBound.height() / 2);

        radius = radius - factor * random.nextInt(2);

        alpha = (1f - factor) * (1 + random.nextFloat());
    }
}

3.ExplosionAnimator

属性动画，用于动画展示

package com.lgl.animview;

import android.animation.ValueAnimator;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Point;
import android.graphics.Rect;
import android.view.View;

/**
 * Created by lgl on 16/01/14.
 */
public class ExplosionAnimator extends ValueAnimator {
    public static final int DEFAULT_DURATION = 1500;
    private Particle[][] mParticles;
    private Paint mPaint;
    private View mContainer;

    public ExplosionAnimator(View view, Bitmap bitmap, Rect bound) {

        mPaint = new Paint();
        mContainer = view;

        setFloatValues(0.0f, 1.0f);
        setDuration(DEFAULT_DURATION);

        mParticles = generateParticles(bitmap, bound);
    }

    private Particle[][] generateParticles(Bitmap bitmap, Rect bound) {
        int w = bound.width();
        int h = bound.height();

        int partW_Count = w / Particle.PART_WH; // 横向个数
        int partH_Count = h / Particle.PART_WH; // 竖向个数

        int bitmap_part_w = bitmap.getWidth() / partW_Count;
        int bitmap_part_h = bitmap.getHeight() / partH_Count;

        Particle[][] particles = new Particle[partH_Count][partW_Count];
        Point point = null;
        for (int row = 0; row < partH_Count; row++) { // 行
            for (int column = 0; column < partW_Count; column++) { // 列
                // 取得当前粒子所在位置的颜色
                int color = bitmap.getPixel(column * bitmap_part_w, row
                        * bitmap_part_h);

                point = new Point(column, row); // x是列，y是行

                particles[row][column] = Particle.generateParticle(color,
                        bound, point);
            }
        }

        return particles;
    }

    public void draw(Canvas canvas) {
        if (!isStarted()) { // 动画结束时停止
            return;
        }
        for (Particle[] particle : mParticles) {
            for (Particle p : particle) {
                p.advance((Float) getAnimatedValue());
                mPaint.setColor(p.color);
                // mPaint.setAlpha((int) (255 * p.alpha)); //只是这样设置，透明色会显示为黑色
                mPaint.setAlpha((int) (Color.alpha(p.color) * p.alpha)); // 这样透明颜色就不是黑色了
                canvas.drawCircle(p.cx, p.cy, p.radius, mPaint);
            }
        }

        mContainer.invalidate();
    }

    @Override
    public void start() {
        super.start();
        mContainer.invalidate();
    }
}

4.ExplosionField

开始执行这个实例的动画了

package com.lgl.animview;

import java.util.ArrayList;

import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;

/**
 * Created by lgl on 16/01/14.
 */
public class ExplosionField extends View {
    private static final String TAG = "ExplosionField";
    private static final Canvas mCanvas = new Canvas();
    private ArrayList<ExplosionAnimator> explosionAnimators;
    private OnClickListener onClickListener;

    public ExplosionField(Context context) {
        super(context);
        init();
    }

    public ExplosionField(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    private void init() {
        explosionAnimators = new ArrayList<ExplosionAnimator>();

        attach2Activity((Activity) getContext());
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        for (ExplosionAnimator animator : explosionAnimators) {
            animator.draw(canvas);
        }
    }

    /**
     * 爆破
     *
     * @param view
     *            使得该view爆破
     */
    public void explode(final View view) {
        Rect rect = new Rect();
        view.getGlobalVisibleRect(rect); // 得到view相对于整个屏幕的坐标
        rect.offset(0, -ParticleUtils.dp2px(25)); // 去掉状态栏高度

        final ExplosionAnimator animator = new ExplosionAnimator(this,
                createBitmapFromView(view), rect);
        explosionAnimators.add(animator);

        animator.addListener(new AnimatorListenerAdapter() {
            @Override
            public void onAnimationStart(Animator animation) {
                view.animate().alpha(0f).setDuration(150).start();
            }

            @Override
            public void onAnimationEnd(Animator animation) {
                view.animate().alpha(1f).setDuration(150).start();

                // 动画结束时从动画集中移除
                explosionAnimators.remove(animation);
                animation = null;
            }
        });
        animator.start();
    }

    private Bitmap createBitmapFromView(View view) {
        /*
         * 为什么屏蔽以下代码段？ 如果ImageView直接得到位图，那么当它设置背景（backgroud)时，不会读取到背景颜色
         */
        // if (view instanceof ImageView) {
        // Drawable drawable = ((ImageView)view).getDrawable();
        // if (drawable != null && drawable instanceof BitmapDrawable) {
        // return ((BitmapDrawable) drawable).getBitmap();
        // }
        // }

        // view.clearFocus(); //不同焦点状态显示的可能不同——（azz:不同就不同有什么关系？）

        Bitmap bitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(),
                Bitmap.Config.ARGB_8888);

        if (bitmap != null) {
            synchronized (mCanvas) {
                mCanvas.setBitmap(bitmap);
                view.draw(mCanvas);
                mCanvas.setBitmap(null); // 清除引用
            }
        }
        return bitmap;
    }

    /**
     * 给Activity加上全屏覆盖的ExplosionField
     */
    private void attach2Activity(Activity activity) {
        ViewGroup rootView = (ViewGroup) activity
                .findViewById(Window.ID_ANDROID_CONTENT);

        ViewGroup.LayoutParams lp = new ViewGroup.LayoutParams(
                ViewGroup.LayoutParams.MATCH_PARENT,
                ViewGroup.LayoutParams.MATCH_PARENT);
        rootView.addView(this, lp);
    }

    /**
     * 希望谁有破碎效果，就给谁加Listener
     *
     * @param view
     *            可以是ViewGroup
     */
    public void addListener(View view) {
        if (view instanceof ViewGroup) {
            ViewGroup viewGroup = (ViewGroup) view;
            int count = viewGroup.getChildCount();
            for (int i = 0; i < count; i++) {
                addListener(viewGroup.getChildAt(i));
            }
        } else {
            view.setClickable(true);
            view.setOnClickListener(getOnClickListener());
        }
    }

    private OnClickListener getOnClickListener() {
        if (null == onClickListener) {

            onClickListener = new OnClickListener() {
                @Override
                public void onClick(View v) {
                    ExplosionField.this.explode(v);

                    // view.setOnClickListener(null); // 用过一次就不需要了
                }
            };
        }

        return onClickListener;
    }
}

5.MainActivity

好的，一切准备好了之后我们就可以使用了

package com.lgl.animview;

import android.app.Activity;
import android.os.Bundle;

public class MainActivity extends Activity {

    // 实例化粒子动画
    private ExplosionField explosionField;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        explosionField = new ExplosionField(this);
        // 绑定哪个控件哪个控件就有效果，如果需要整个layout，只要绑定根布局的id即可
        explosionField.addListener(findViewById(R.id.iv_round));
    }
}

在xml中我们什么也不用做，好的，让我们来运行一下

好的，本篇博客也到此结束了，喜欢的点个赞

Demo下载：http://download.csdn.net/detail/qq_26787115/9409139