【Android】Bitmap图片裁剪（91/100）

自定义裁剪类CropImageView：

package top.lc951.myandroid.views;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.support.annotation.Nullable;
import android.util.AttributeSet;
import android.view.View;

import top.lc951.myandroid.utils.BitmapUtil;

/**
 * @author lichong
 * 2022年07月26日19:48:17
 */
public class CropImageView extends View {
    private Paint mPaintShade;
    private Bitmap mOrigBitmap=null;
    private Bitmap mCropBitmap=null;

    private Rect mRect=new Rect(0,0,0,0);

    public CropImageView(Context context) {
        this(context,null);
    }

    public CropImageView(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
        mPaintShade=new Paint();
        mPaintShade.setColor(0x99000000);
    }

    public void setOriginBitmap(Bitmap origin){
        mOrigBitmap=origin;
    }

    public Bitmap getCropBitmap(){
        return mCropBitmap;
    }

    public boolean setBitmapRect(Rect rect){
        if(null==mOrigBitmap){
            return false;
        }else if(rect.leftmOrigBitmap.getWidth()){
            return false;
        }else if(rect.top  mOrigBitmap.getHeight()){
            return false;
        }else if (rect.right  mOrigBitmap.getWidth()) { // 右侧边界非法
            return false;
        } else if (rect.bottom  mOrigBitmap.getHeight()) { // 下方边界非法
            return false;
        }

        mRect = rect;
        // 根据指定的四周边界，裁剪相应尺寸的位图对象
        mCropBitmap = Bitmap.createBitmap(mOrigBitmap,
                mRect.left, mRect.top, mRect.right, mRect.bottom);
        postInvalidate(); // 立即刷新视图（线程安全方式）
        return true;
    }

    // 获取位图的矩形边界
    public Rect getBitmapRect() {
        return mRect;
    }
    // 左右翻转图像
    public void flip() {
        // 水平翻转图像，也就是把镜中像左右翻过来
        mCropBitmap = BitmapUtil.getFlipBitmap(mCropBitmap);
        postInvalidate(); // 立即刷新视图（线程安全方式）
    }
    // 在下级视图都绘制完成后触发
    @Override
    protected void dispatchDraw(Canvas canvas) {
        if (mOrigBitmap == null) {
            return;
        }
        // 画外圈阴影
        Rect rectShade = new Rect(0, 0, getMeasuredWidth(), getMeasuredHeight());
        canvas.drawRect(rectShade, mPaintShade);
        // 画高亮处的图像
        canvas.drawBitmap(mCropBitmap, mRect.left, mRect.top, new Paint());
    }

}

布局：

应用：

package top.lc951.myandroid.activity;

import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Rect;
import android.os.Environment;
import android.os.Handler;
import android.os.Looper;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Spinner;
import android.widget.Toast;

import top.lc951.myandroid.R;
import top.lc951.myandroid.utils.BitmapUtil;
import top.lc951.myandroid.views.CropImageView;

/**
 * 图片裁剪
 */
public class BitmapCutActivity extends AppCompatActivity {
    private CropImageView cropImageView;
    private ImageView originIv;
    private ImageView newIv;

    public static void actionActivity(Context context) {
        Intent intent = new Intent(context, BitmapCutActivity.class);
        context.startActivity(intent);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_bitmap_cut);
        bindViews();
        initSpinner();

    }

    private String[] array = {"不裁剪", "中间", "左上角", "右上角", "左下角", "右下角"};

    private void initSpinner() {
        ArrayAdapter colorAdapter = new ArrayAdapter(this,
                android.R.layout.simple_list_item_1, array);
        Spinner spinner = findViewById(R.id.spinner);
        spinner.setAdapter(colorAdapter);
        spinner.setSelection(0);
        spinner.setPrompt("请选择裁剪区域");

        spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView parent, View view, int position, long id) {
                cropImageView.setVisibility(position == 0 ? View.GONE : View.VISIBLE);
                Bitmap bitmap = originIv.getDrawingCache();
                int width = bitmap.getWidth(), height = bitmap.getHeight();
                cropImageView.setOriginBitmap(bitmap);

                switch (position) {
                    case 1:
                        cropImageView.setBitmapRect(new Rect(width/4, height/4, width/2, height/2));
                        break;
                    case 2:
                        cropImageView.setBitmapRect(new Rect(0, 0, width/2, height/2));

                        break;
                    case 3:
                        cropImageView.setBitmapRect(new Rect(width/2, 0, width/2, height/2));

                        break;
                    case 4:
                        cropImageView.setBitmapRect(new Rect(0, height/2, width/2, height/2));

                        break;
                    case 5:
                        cropImageView.setBitmapRect(new Rect(width/2, height/2, width/2, height/2));
                        break;
                }
            }

            @Override
            public void onNothingSelected(AdapterView parent) {

            }
        });
    }

    private void bindViews() {
        cropImageView = findViewById(R.id.iv_crop);
        originIv = findViewById(R.id.iv_origin);
        newIv = findViewById(R.id.iv_new);
        originIv.setDrawingCacheEnabled(true);// 开启位图视图的绘图缓存
        originIv.setImageResource(R.mipmap.ic_img06);
        new Handler(Looper.myLooper())
                .postDelayed(new Runnable() {
                    @Override
                    public void run() {
                        initSpinner();
                    }
                }, 200);

        Button saveBtn = findViewById(R.id.btn_save_image);
        saveBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                cropImageView.setVisibility(View.GONE);
                Bitmap bitmap = cropImageView.getCropBitmap();
                newIv.setImageBitmap(bitmap);

                // 生成图片文件的保存路径
//                String path = String.format("%s/%s.jpg",
//                        getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS).toString(),
//                        DateUtil.getNowDateTime());
//                BitmapUtil.saveImage(path, bitmap); // 把位图保存为图片文件
//                BitmapUtil.notifyPhotoAlbum(BitmapCutActivity.this, path); // 通知相册来了张新图片
//                Toast.makeText(BitmapCutActivity.this, "成功保存图片文件：" + path, Toast.LENGTH_SHORT).show();
            }
        });
    }
}