Android中TextView和ImageView实现倾斜效果

TextView倾斜：

想做一个倾斜的TextView,想海报上显示的那样 ,在网上找例子一直不能实现,看了看TextView源码,发现很简单,为方便像我一样糊涂的孩纸,贴出来了.

首先需要先自定义一个TextView

public class MyTextView extends TextView{ 

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

  @Override
  protected void onDraw(Canvas canvas) {
    //倾斜度45,上下左右居中
    canvas.rotate(-45, getMeasuredWidth()/2, getMeasuredHeight()/2);
    super.onDraw(canvas);
  } 

}

xml文件中添加上这个MyTextView

<com.peace.test.incline_textview.MyTextView
    android:layout_width="100dip"
    android:layout_height="100dip"
    android:gravity="center"
    android:text="@string/hello_world"/>

ImageView倾斜：

MainActivity如下:

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:
 * 利用mImageView.setImageMatrix(matrix)实现
 * 图片的平移,缩放,旋转,倾斜以及对称
 *
 * 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> 

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持我们。