Android图片处理Matrix详细示例

MainActivity如下:

package cn.testmatrix;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.ImageView;
import android.app.Activity;
import android.graphics.Matrix;
/**
 * Demo描述:
 * Matrix类的使用
 * 平移 缩放 旋转 倾斜
 * 
 * 参考资料:
 * 0 http://blog.csdn.net/pathuang68/article/details/6991988
 * 1 http://blog.csdn.net/mingli198611/article/details/7830633
 * 
 * Thank you very much
 */
public class MainActivity extends Activity {
    private TestMatrixImageView mTestMatrixImageView;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		mTestMatrixImageView=new TestMatrixImageView(MainActivity.this);
		mTestMatrixImageView.setScaleType(ImageView.ScaleType.MATRIX);//??
		mTestMatrixImageView.setOnTouchListener(new TouchListenerImpl());
		setContentView(mTestMatrixImageView);
	}
	
	private class TouchListenerImpl implements OnTouchListener{
		@Override
		public boolean onTouch(View v, MotionEvent event) {
			if (event.getAction()==MotionEvent.ACTION_UP) {
				//1 测试平移
				testTranslate();
				//2 测试围绕图片中心点旋转
				//testRotate();
				//3 测试围绕原点旋转后平移
				//testRotateAndTranslate();
				//4 缩放
				//testScale();
				//5 水平倾斜
				//testSkewX();
				//6 垂直倾斜
				//testSkewY();
				//7 水平且垂直倾斜
				//testSkewXY();
				//8 水平对称
				//testSymmetryX();
				//9 垂直对称
				//testSymmetryY();
				//10 关于X=Y对称
				//testSymmetryXY();
			}
			return true;
		}
		
	}
	
	//平移
	private void testTranslate(){
		Matrix matrix=new Matrix();
		int width=mTestMatrixImageView.getBitmap().getWidth();
		int height=mTestMatrixImageView.getBitmap().getHeight();
		matrix.postTranslate(width, height);
		mTestMatrixImageView.setImageMatrix(matrix);
		showMatrixEveryValue(matrix);
	}
	//围绕图片中心点旋转
	private void testRotate(){
		Matrix matrix=new Matrix();
		int width=mTestMatrixImageView.getBitmap().getWidth();
		int height=mTestMatrixImageView.getBitmap().getHeight();
		matrix.postRotate(45f, width/2, height/2);
		matrix.postTranslate(width, height);
		mTestMatrixImageView.setImageMatrix(matrix);
		showMatrixEveryValue(matrix);
	}
	
	//围绕原点旋转后平移
	//注意以下三行代码的执行顺序:
	//matrix.setRotate(45f);
	//matrix.preTranslate(-width, -height);
	//matrix.postTranslate(width, height);
	//先执行matrix.preTranslate(-width, -height);
	//后执行matrix.setRotate(45f);
	//再执行matrix.postTranslate(width, height);
	private void testRotateAndTranslate() {
		Matrix matrix = new Matrix();
		int width = mTestMatrixImageView.getBitmap().getWidth();
		int height = mTestMatrixImageView.getBitmap().getHeight();
		matrix.setRotate(45f);
		matrix.preTranslate(-width, -height);
		matrix.postTranslate(width, height);
		mTestMatrixImageView.setImageMatrix(matrix);
		showMatrixEveryValue(matrix);
	}
	
	//缩放
	private void testScale() {
		Matrix matrix = new Matrix();
		matrix.setScale(0.5f, 0.5f);
		mTestMatrixImageView.setImageMatrix(matrix);
		showMatrixEveryValue(matrix);
	}
	
	//水平倾斜
	private void testSkewX() {
		Matrix matrix = new Matrix();
		matrix.setSkew(0.5f, 0);
		mTestMatrixImageView.setImageMatrix(matrix);
		showMatrixEveryValue(matrix);
	}

	// 垂直倾斜
	private void testSkewY() {
		Matrix matrix = new Matrix();
		matrix.setSkew(0, 0.5f);
		mTestMatrixImageView.setImageMatrix(matrix);
		showMatrixEveryValue(matrix);
	}
	
	// 水平且垂直倾斜
	private void testSkewXY() {
		Matrix matrix = new Matrix();
		matrix.setSkew(0.5f, 0.5f);
		mTestMatrixImageView.setImageMatrix(matrix);
		showMatrixEveryValue(matrix);
	}
	
	// 水平对称--图片关于X轴对称
	private void testSymmetryX() {
		Matrix matrix = new Matrix();
		int height = mTestMatrixImageView.getBitmap().getHeight();
		float matrixValues[] = { 1f, 0f, 0f, 0f, -1f, 0f, 0f, 0f, 1f };
		matrix.setValues(matrixValues);
		//若是matrix.postTranslate(0, height);
		//表示将图片上下倒置
		matrix.postTranslate(0, height*2);
		mTestMatrixImageView.setImageMatrix(matrix);
		showMatrixEveryValue(matrix);
	}
	
	// 垂直对称--图片关于Y轴对称
	private void testSymmetryY() {
		Matrix matrix = new Matrix();
		int width=mTestMatrixImageView.getBitmap().getWidth();
		float matrixValues[] = {-1f, 0f, 0f, 0f, 1f, 0f, 0f, 0f, 1f};
		matrix.setValues(matrixValues);
		//若是matrix.postTranslate(width,0);
		//表示将图片左右倒置
		matrix.postTranslate(width*2, 0);
		mTestMatrixImageView.setImageMatrix(matrix);
		showMatrixEveryValue(matrix);

	}

	// 关于X=Y对称--图片关于X=Y轴对称
	private void testSymmetryXY() {
		Matrix matrix = new Matrix();
		int width = mTestMatrixImageView.getBitmap().getWidth();
		int height = mTestMatrixImageView.getBitmap().getHeight();
		float matrixValues[] = { 0f, -1f, 0f, -1f, 0f, 0f, 0f, 0f, 1f };
		matrix.setValues(matrixValues);
		matrix.postTranslate(width+height, width+height);
		mTestMatrixImageView.setImageMatrix(matrix);
		showMatrixEveryValue(matrix);
	}
	
	//获取变换矩阵Matrix中的每个值
	private void showMatrixEveryValue(Matrix matrix){
		float matrixValues []=new float[9];
		matrix.getValues(matrixValues);
		for (int i = 0; i <3; i++) {
			String valueString="";
			for (int j = 0; j < 3; j++) {
				valueString=matrixValues[3*i+j]+"";
				System.out.println("第"+(i+1)+"行的第"+(j+1)+"列的值为"+valueString);
			}
		}
	}

}

TestMatrixImageView如下:

package cn.testmatrix;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.widget.ImageView;
/**
 * 总结:
 * 在MainActivity中执行:
 * mTestMatrixImageView.setImageMatrix(matrix);
 * 时此自定义View会先调用setImageMatrix(Matrix matrix)
 * 然后调用onDraw(Canvas canvas)
 */
public class TestMatrixImageView extends ImageView{
	private Matrix mMatrix;
    private Bitmap mBitmap;
	public TestMatrixImageView(Context context) {
		super(context);
		mMatrix=new Matrix();
		mBitmap=BitmapFactory.decodeResource(getResources(), R.drawable.icon);
	}
	@Override
	protected void onDraw(Canvas canvas) {
		System.out.println("---> onDraw");
		//画原图
		canvas.drawBitmap(mBitmap, 0, 0, null);
		//画经过Matrix变化后的图
		canvas.drawBitmap(mBitmap, mMatrix, null);
		super.onDraw(canvas);
	}
	@Override
	public void setImageMatrix(Matrix matrix) {
		System.out.println("---> setImageMatrix");
		this.mMatrix.set(matrix);
		super.setImageMatrix(matrix);
	}
	
	public Bitmap getBitmap(){
		System.out.println("---> getBitmap");
		return mBitmap;
	}

}

main.xml如下:

<RelativeLayout 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"
    >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />

</RelativeLayout>