图片旋转

来源：互联网发布：汇川plc软件编辑：程序博客网时间：2024/04/29 10:44

android图片旋转是老话题了，但如何简单迅速无BUG的解决它是需要想一想的。

首先回顾一下android 图片旋转提供的API有哪些

1.Matrix

2.Animation

说白了 Animation的核心也是Matrix。而且Animation真是扩展性不强也不好用，用过的应该都知道。

那我们开始走Matrix路线吧。下面是游戏中用到的箭头选择并动画在原地来回偏移。

核心代码如下

package com.laahaa.view.extension;import com.laahaa.R;import com.laahaa.config.ExtensionLayoutConfig;import android.content.Context;import android.graphics.Bitmap;import android.graphics.Matrix;import android.graphics.drawable.BitmapDrawable;import android.view.Gravity;import android.widget.FrameLayout;import android.widget.FrameLayout.LayoutParams;import android.widget.ImageView;/** *  * <p>class name:中间箭头</p> * <p>class instruction:</p> * @author Mercury  Create in 2012-2-7 */public class CenterArrow extends ImageView{    FrameLayout.LayoutParams lp;    private Bitmap bitmap;    private Matrix matrix = new Matrix();         public CenterArrow(Context context) {        super(context);         lp=new FrameLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT,Gravity.CENTER);    }    /**     * 线程每次间隔时间调用     * @param dir     */    public void onTick(int dir)    {        switch (dir) {        case 0:            if(lp.bottomMargin==(ExtensionLayoutConfig.CenterArrowWidth+ExtensionLayoutConfig.CenterCircleWidth))                lp.bottomMargin+=ExtensionLayoutConfig.ArrowOffset;            else                lp.bottomMargin-=ExtensionLayoutConfig.ArrowOffset;            break;        case 1:                        if(lp.leftMargin==(ExtensionLayoutConfig.CenterArrowWidth+ExtensionLayoutConfig.CenterCircleWidth))                lp.leftMargin+=ExtensionLayoutConfig.ArrowOffset;            else                lp.leftMargin-=ExtensionLayoutConfig.ArrowOffset;            break;        case 2:                    if(lp.bottomMargin==-(ExtensionLayoutConfig.CenterArrowWidth+ExtensionLayoutConfig.CenterCircleWidth))                lp.bottomMargin-=ExtensionLayoutConfig.ArrowOffset;            else                lp.bottomMargin+=ExtensionLayoutConfig.ArrowOffset;            break;        case 3:            if(lp.leftMargin==-(ExtensionLayoutConfig.CenterArrowWidth+ExtensionLayoutConfig.CenterCircleWidth))                lp.leftMargin-=ExtensionLayoutConfig.ArrowOffset;            else                lp.leftMargin+=ExtensionLayoutConfig.ArrowOffset;            break;        }        this.setLayoutParams(lp);        this.setImageBitmap(bitmap);    }    public void setRotate(int dir)    {        int degrees=0;        switch (dir) {        case 0:            degrees=90;            lp.leftMargin=0;            lp.rightMargin=0;            lp.bottomMargin=ExtensionLayoutConfig.CenterArrowWidth+ExtensionLayoutConfig.CenterCircleWidth;            lp.topMargin=0;            break;        case 1:            degrees=0;            lp.leftMargin=ExtensionLayoutConfig.CenterArrowWidth+ExtensionLayoutConfig.CenterCircleWidth;            lp.rightMargin=0;            lp.bottomMargin=0;            lp.topMargin=0;            break;        case 2:            degrees=270;            lp.leftMargin=0;            lp.rightMargin=0;            lp.bottomMargin=-(ExtensionLayoutConfig.CenterArrowWidth+ExtensionLayoutConfig.CenterCircleWidth);            lp.topMargin=0;            break;        case 3:            degrees=180;            lp.leftMargin=-(ExtensionLayoutConfig.CenterArrowWidth+ExtensionLayoutConfig.CenterCircleWidth);            lp.rightMargin=0;            lp.bottomMargin=0;            lp.topMargin=0;            break;        }         bitmap=((BitmapDrawable) getResources().getDrawable(R.drawable.arrow)).getBitmap();            this.setLayoutParams(lp);          //设置图像的旋转角度              matrix.setRotate(degrees);          //旋转图像，并生成新的Bitmap对像            bitmap=Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);          //重新在ImageView组件中显示旋转后的图像            this.setImageBitmap(bitmap);     }}