【安卓笔记】仿乐安全首页动态效果

先看效果：

布局：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center"
    tools:context=".MainActivity" >
    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent" >
        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:src="@drawable/homepage_disk_button_orange_normal" />
        <ImageView
            android:id="@+id/iv_rotate"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:src="@drawable/homepage_disk_orange_normal" />
        <com.example.view.RadiationView
            android:id="@+id/rv"
            android:layout_width="250dp"
            android:layout_height="250dp"
            android:layout_gravity="center" />
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:text="SB"
            android:textColor="#ffffff"
            android:textSize="30sp" />
    </FrameLayout>
</LinearLayout>

旋转动画：

<?xml version="1.0" encoding="utf-8"?>
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
    android:duration="12000"
    android:fromDegrees="0"
    android:pivotX="50%"
    android:pivotY="50%"
    android:startOffset="0"
    android:interpolator="@android:anim/linear_interpolator"
    android:repeatCount="infinite"
    android:repeatMode="restart"
    android:toDegrees="360" />

带辐射效果的view：

package com.example.view;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.os.Handler;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
/**
 * @author Rowandjj
 *
 *带辐射效果的view
 */
public class RadiationView extends View
{
	/**
	 *画笔
	 */
	private Paint mPaint = new Paint();

	/**
	 *颜色
	 */
	private int mColor = 0x3f990e;

	/**
	 * 透明度
	 */
	private int mAlpha = 60;

	private Handler mHandler = null;

	private static final int MESSAGE_DRAW = 0;
	private static final String TAG = "RadiationView";

	private int width;
	private int height;

	/**
	 * 扩散速度
	 */
	private int speed = 30;
	/**
	 *最大辐射半径
	 */
	private int maxRadius = 100;

	private int centerX;
	private int centerY;

	/**
	 * 最小半径
	 */
	private int minRadius = 70;
	/**
	 * 当前半径
	 */
	private int radius = minRadius;

	private boolean isStarted = false;

	public RadiationView(Context context)
	{
		super(context);
		init();
	}
	public RadiationView(Context context, AttributeSet attrs)
	{
		super(context, attrs, 0);
		init();
	}
	public void startRadiate()
	{
		isStarted = true;
		mHandler.sendEmptyMessage(MESSAGE_DRAW);
	}

	private void init()
	{
		mPaint = new Paint();
		mPaint.setStrokeWidth(1);
		//必须先设置color，再设置alpha
		mPaint.setColor(mColor);
		mPaint.setAlpha(mAlpha);

		mHandler = new Handler()
		{
			public void handleMessage(android.os.Message msg)
			{
				if(msg.what == MESSAGE_DRAW)
				{
					invalidate();
					if(isStarted)
					{
						sendEmptyMessageDelayed(MESSAGE_DRAW,speed);
					}
				}
			}
		};
	}

	@Override
	protected void onLayout(boolean changed, int left, int top, int right,
			int bottom)
	{
		super.onLayout(changed, left, top, right, bottom);
		width = this.getWidth();
		height = this.getHeight();
		if(width <= 0 || height<=0)
		{
			throw new RuntimeException("size illegal");
		}
		//中心点
		centerX = width/2;
	    centerY = height/2;
		//最大辐射半径
		maxRadius = (width > height) ? height/2 : width/2;
		Log.i(TAG,"MAX"+maxRadius);
		if(maxRadius < 70)
		{
			throw new RuntimeException("size too small");
		}
	}
	@Override
	protected void onDraw(Canvas canvas)
	{
		mPaint.setColor(mColor);
		mPaint.setAlpha(mAlpha);
		if(radius <= 0)
		{
			return;
		}
		if(radius > maxRadius)
		{
			radius = minRadius;
		}
		canvas.save();
		canvas.drawCircle(centerX, centerY, radius, mPaint);
		canvas.restore();
		radius += 1;
	}
	@Override
	protected void onAttachedToWindow()
	{
		super.onAttachedToWindow();
		this.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
	}

	public void setColor(int color)
	{
		this.mColor = color;
	}

	public void setSpeed(int speed)
	{
		this.speed = speed;
	}

	public void setMinRadius(int radius)
	{
		this.minRadius = radius;
	}
}

调用的代码：

package com.example.animdemo1;
import android.app.Activity;
import android.os.Bundle;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.ImageView;
import com.example.view.RadiationView;
public class MainActivity extends Activity
{
	private ImageView iv = null;
	private RadiationView rv = null;
	@Override
	protected void onCreate(Bundle savedInstanceState)
	{
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		iv = (ImageView) findViewById(R.id.iv_rotate);
		rv = (RadiationView) findViewById(R.id.rv);
		rv.setMinRadius(70);//辐射半径
		rv.startRadiate();//开始辐射
		Animation anim = AnimationUtils.loadAnimation(this, R.anim.rotate_circle_anim);
		iv.startAnimation(anim);//开始动画
	}
}