由于业务需要写了一个Android手机拍照的功能Demo,同时实现了图片剪裁和图片压缩。以下是源码
package com.klp.demo_025;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
public class MainActivity extends Activity {
private ImageView iv;
private Button button;
private File file;
private Uri uri;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
iv = (ImageView) findViewById(R.id.imageView1);
button = (Button) findViewById(R.id.button1);
file = new File(this.getExternalFilesDir(null), "image.jpg");
uri = Uri.fromFile(file);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
intent.putExtra(MediaStore.Images.Media.ORIENTATION, 0);
intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
startActivityForResult(intent, 2);
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) {
if (requestCode == 2) {
startPhotoZoom(uri);
} else {
try {
BitmapFactory.Options options = new BitmapFactory.Options();
options.inSampleSize = 2;
Bitmap bitmap = BitmapFactory.decodeFile(file.getPath(),
options);
// 压缩图片
// bitmap = compressImage(bitmap,500);
if (bitmap != null) {
// 显示图片
iv.setImageBitmap(bitmap);
// 保存图片
FileOutputStream fos = null;
fos = new FileOutputStream(file);
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, fos);
fos.flush();
fos.close();
}
} catch (Exception e) {
// TODO: handle exception
}
}
}
}
/**
* 裁剪图片
*
* @param uri
*/
public void startPhotoZoom(Uri uri) {
Intent intent = new Intent("com.android.camera.action.CROP");
intent.setDataAndType(uri, "image/*");
intent.putExtra("crop", "true");// crop=true 有这句才能出来最后的裁剪页面.
intent.putExtra("aspectX", 1);// 这两项为裁剪框的比例.
intent.putExtra("aspectY", 1);// x:y=1:1
intent.putExtra("outputX", 200);//图片输出大小
intent.putExtra("outputY", 200);
intent.putExtra("output", uri);
intent.putExtra("outputFormat", "JPEG");// 返回格式
startActivityForResult(intent, 3);
}
/**
* 将图片image压缩成大小为 size的图片(size表示图片大小,单位是KB)
*
* @param image
* 图片资源
* @param size
* 图片大小
* @return Bitmap
*/
private Bitmap compressImage(Bitmap image, int size) {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
// 质量压缩方法,这里100表示不压缩,把压缩后的数据存放到baos中
image.compress(Bitmap.CompressFormat.JPEG, 100, baos);
int options = 100;
// 循环判断如果压缩后图片是否大于100kb,大于继续压缩
while (baos.toByteArray().length / 1024 > size) {
// 重置baos即清空baos
baos.reset();
// 每次都减少10
options -= 10;
// 这里压缩options%,把压缩后的数据存放到baos中
image.compress(Bitmap.CompressFormat.JPEG, options, baos);
}
// 把压缩后的数据baos存放到ByteArrayInputStream中
ByteArrayInputStream isBm = new ByteArrayInputStream(baos.toByteArray());
// 把ByteArrayInputStream数据生成图片
Bitmap bitmap = BitmapFactory.decodeStream(isBm, null, null);
return bitmap;
}
}
下面是布局,很简单