图片处理（旋转，平移，缩放）View---Canvas;Paint;Bitmap

【1.最终效果】

（1）（2）

（3）（4）

【2.xml文件】

<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"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context=".MainActivity" >    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="@string/hello_world" /></RelativeLayout>

【3.view文件】

package com.example.tupian2;import android.content.Context;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Matrix;import android.graphics.Paint;import android.util.AttributeSet;import android.view.View;public class MyView extends View {Paint paint;Bitmap bitmap;public MyView(Context context, AttributeSet attrs) {super(context, attrs);this.initBitmap();}public void initBitmap() {paint = new Paint();bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.img);}/* * 调用setConcat方法，将对应的两个Matrix对象连接起来并绘制，最后恢复画布状态 * */protected void onDraw(Canvas canvas) {super.onDraw(canvas);paint.setAntiAlias(true);paint.setColor(Color.BLUE);paint.setTextSize(15);canvas.drawBitmap(bitmap, 10, 10, paint); // 第1个图canvas.save();/* * 调用setTranslate方法平移矩阵，setScale方法缩放矩阵，setCRotate方法旋转 * */Matrix m1 = new Matrix();m1.setTranslate(1000, 100);Matrix m2 = new Matrix();m2.setRotate(30);Matrix m3 = new Matrix();m3.setConcat(m1, m2);m1.setScale(0.8f, 0.8f);m2.setConcat(m3, m1);canvas.drawBitmap(bitmap, m2, paint); // 第2个图canvas.restore();canvas.save();paint.setAlpha(180);m1.setTranslate(200, 300);m2.setScale(1.3f, 1.3f);m3.setConcat(m1, m2);canvas.drawBitmap(bitmap, m3, paint);// 第3个图paint.reset(); // 恢复画笔设置canvas.restore();// 恢复画布paint.setTextSize(40);paint.setColor(Color.RED);canvas.drawText("图片高度:" + bitmap.getHeight(), 100, 800, paint);canvas.drawText("图片宽度:" + bitmap.getWidth(), 100, 900, paint);paint.reset();}}

【4.Activity文件】

package com.example.tupian2;import android.os.Bundle;import android.app.Activity;import android.content.pm.ActivityInfo;import android.view.Menu;import android.view.Window;import android.view.WindowManager;

public class MainActivity extends Activity {

    public void onCreate(Bundle savedInstanceState){     super.onCreate(savedInstanceState);/*     去掉名称 。没有这一行的效果如图：（2）*/   requestWindowFeature(Window.FEATURE_NO_TITLE); /*   去掉电量显示这些。没有这一行，效果如图：（3）*/   getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,            WindowManager.LayoutParams.FLAG_FULLSCREEN);/*     设置横屏。没有这一行，效果如图：（4）*/  /* setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);*/      setContentView(R.layout.activity_main);    }  }

【4.过程错误：】

03-25 20:19:20.348: E/AndroidRuntime(4235): FATAL EXCEPTION: main
03-25 20:19:20.348: E/AndroidRuntime(4235): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.tupian2/com.example.tupian2.MainActivity}: android.view.InflateException: Binary XML file line #10: Error inflating class com.example.MyView
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2319)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2383)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.app.ActivityThread.access$600(ActivityThread.java:156)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1340)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.os.Handler.dispatchMessage(Handler.java:99)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.os.Looper.loop(Looper.java:153)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.app.ActivityThread.main(ActivityThread.java:5331)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at java.lang.reflect.Method.invokeNative(Native Method)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at java.lang.reflect.Method.invoke(Method.java:511)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:842)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at dalvik.system.NativeStart.main(Native Method)
03-25 20:19:20.348: E/AndroidRuntime(4235): Caused by: android.view.InflateException: Binary XML file line #10: Error inflating class com.example.MyView
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:698)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.view.LayoutInflater.rInflate(LayoutInflater.java:746)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.view.LayoutInflater.inflate(LayoutInflater.java:352)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:274)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.app.Activity.setContentView(Activity.java:1943)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at com.example.tupian2.MainActivity.onCreate(MainActivity.java:17)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.app.Activity.performCreate(Activity.java:5191)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1091)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2283)
03-25 20:19:20.348: E/AndroidRuntime(4235):  ... 11 more
03-25 20:19:20.348: E/AndroidRuntime(4235): Caused by: java.lang.ClassNotFoundException: Didn't 03-25 20:19:20.348: E/AndroidRuntime(4235): FATAL EXCEPTION: main
03-25 20:19:20.348: E/AndroidRuntime(4235): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.tupian2/com.example.tupian2.MainActivity}: android.view.InflateException: Binary XML file line #10: Error inflating class com.example.MyView
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2319)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2383)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.app.ActivityThread.access$600(ActivityThread.java:156)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1340)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.os.Handler.dispatchMessage(Handler.java:99)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.os.Looper.loop(Looper.java:153)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.app.ActivityThread.main(ActivityThread.java:5331)
03-25 20:19:20.348: E/AndroidRuntime(4235): at java.lang.reflect.Method.invokeNative(Native Method)
03-25 20:19:20.348: E/AndroidRuntime(4235): at java.lang.reflect.Method.invoke(Method.java:511)
03-25 20:19:20.348: E/AndroidRuntime(4235): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:842)
03-25 20:19:20.348: E/AndroidRuntime(4235): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609)
03-25 20:19:20.348: E/AndroidRuntime(4235): at dalvik.system.NativeStart.main(Native Method)
03-25 20:19:20.348: E/AndroidRuntime(4235): Caused by: android.view.InflateException: Binary XML file line #10: Error inflating class com.example.MyView
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:698)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.view.LayoutInflater.rInflate(LayoutInflater.java:746)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.view.LayoutInflater.inflate(LayoutInflater.java:352)
03-25 20:19:20.348: E/AndroidRuntime(4235): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:274)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.app.Activity.setContentView(Activity.java:1943)
03-25 20:19:20.348: E/AndroidRuntime(4235): at com.example.tupian2.MainActivity.onCreate(MainActivity.java:17)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.app.Activity.performCreate(Activity.java:5191)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1091)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2283)
03-25 20:19:20.348: E/AndroidRuntime(4235): ... 11 more
03-25 20:19:20.348: E/AndroidRuntime(4235): Caused by: java.lang.ClassNotFoundException: Didn't find class "com.example.MyView" on path: DexPathList[dexElements=[zip file "/data/app/com.example.tupian2-2.apk"],nativeLibraryDirectories=[/data/app-lib/com.example.tupian2-2, /vendor/lib, /system/lib]]
03-25 20:19:20.348: E/AndroidRuntime(4235): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:53)
03-25 20:19:20.348: E/AndroidRuntime(4235): at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
03-25 20:19:20.348: E/AndroidRuntime(4235): at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.view.LayoutInflater.createView(LayoutInflater.java:552)
03-25 20:19:20.348: E/AndroidRuntime(4235): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:687)
03-25 20:19:20.348: E/AndroidRuntime(4235): ... 21 more
find class "com.example.MyView" on path: DexPathList[dexElements=[zip file "/data/app/com.example.tupian2-2.apk"],nativeLibraryDirectories=[/data/app-lib/com.example.tupian2-2, /vendor/lib, /system/lib]]
03-25 20:19:20.348: E/AndroidRuntime(4235):  at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:53)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.view.LayoutInflater.createView(LayoutInflater.java:552)
03-25 20:19:20.348: E/AndroidRuntime(4235):  at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:687)
03-25 20:19:20.348: E/AndroidRuntime(4235):  ... 21 more

找不到com.example.MyView类，改成com.example.tupian.MyView后，，程序没有错误了