package com.loaderman.customviewdemo;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.Paint;
import
 
 android.os.Bundle;
import android.widget.ImageView;
import android.widget.SeekBar;
import android.widget.TextView;

public class MainActivity extends Activity {
    private SeekBar mSeekBar;
    private ImageView mImageView;
    private Bitmap mOriginBmp,mTempBmp;
    @Override
    protected
 
 void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mImageView = (ImageView) findViewById(R.id.img);
        mSeekBar = (SeekBar)findViewById(R.id.seekbar);
        mOriginBmp = BitmapFactory.decodeResource(getResources(), R.drawable.dog);
        mTempBmp 
 
= Bitmap.createBitmap(mOriginBmp.getWidth(), mOriginBmp.getHeight(),
                Bitmap.Config.ARGB_8888);
        TextView tv = (TextView)findViewById(R.id.tv);
        tv.setText("色彩旋轉(-180——180):");


        mSeekBar.setMax(360);
        mSeekBar.setProgress(180);

        mSeekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            @Override
            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {

                Bitmap bitmap = handleColorRotateBmp(progress);
                mImageView.setImageBitmap(bitmap);
            }

            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {

            }

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {

            }
        });

    }

    private Bitmap handleColorRotateBmp(int progress){

        // 建立一個相同尺寸的可變的點陣圖區,用於繪製調色後的圖片
        Canvas canvas = new Canvas(mTempBmp); // 得到畫筆物件
        Paint paint = new Paint(); // 新建paint
        paint.setAntiAlias(true); // 設定抗鋸齒,也即是邊緣做平滑處理
        ColorMatrix colorMatrix = new ColorMatrix();

        colorMatrix.setRotate(0,progress-180);

        paint.setColorFilter(new ColorMatrixColorFilter(colorMatrix));// 設定顏色變換效果
        canvas.drawBitmap(mOriginBmp, 0, 0, paint); // 將顏色變化後的圖片輸出到新建立的點陣圖區
        // 返回新的點陣圖，也即調色處理後的圖片
        return mTempBmp;
    }
}

效果: