Android:拍照功能及将图片压缩存入指定路径的方法

package com.example.administrator.testapplication;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Environment;
import android.provider.MediaStore;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.Window;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ImageView;

import java.io.File;
import java.io.IOException;
import java.math.BigDecimal;

public class MainActivity extends Activity {

private ImageView img;
private static final String TEMP_PATH = Environment.getExternalStorageDirectory().getAbsolutePath() + "/tmp/temp_" + System.currentTimeMillis() + ".jpg";
private static final int REQ_CARMER = 0x002;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.activity_main);

isFolderExists(Environment.getExternalStorageDirectory().getAbsolutePath() + "/tmp/");//判断目录是否存在
checkFile(TEMP_PATH);//检查文件是否存在
img = (ImageView) findViewById(R.id.img);
findViewById(R.id.btn).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
takePhoto();
}
});
}
//检查文件是否存在
private void checkFile(String path)
{
File file = new File(path);
if (!file.exists())
{
try
{
file.createNewFile();
} catch (IOException e)
{
e.printStackTrace();
}
}
}
//判断目录是否存在
boolean isFolderExists(String strFolder)
{
File file = new File(strFolder);
if (!file.exists())
{
if (file.mkdirs())
{
return true;
} else
{
return false;

}
}
return true;

}
private void takePhoto()
{
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
//path为保存图片的路径，执行完拍照以后能保存到指定的路径下
File file = new File(TEMP_PATH);
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(file));
intent.putExtra(MediaStore.Images.Media.ORIENTATION, 0);
startActivityForResult(intent, REQ_CARMER);
}
//图片压缩
public Bitmap setImage(String path, Intent intent)
{
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(path, options);

//        double value = new BigDecimal(options.outWidth).divide(new BigDecimal(options.outHeight), 4, BigDecimal.ROUND_HALF_UP).doubleValue();

//        intent.putExtra(Constants.ISNULL, false);
//        intent.putExtra(Constants.IMGPATH, path);
//        intent.putExtra(Constants.ASPECT_RATIO, value == 0d ? "1.0000" : format.format(value));

options.inJustDecodeBounds = false;

int be = Math.max(options.outWidth, options.outHeight) / 20;
if (be % 10 != 0)
be += 10;
be = be / 10;
if (be <= 0)
be = 1;
options.inSampleSize = be;
return BitmapFactory.decodeFile(path, options);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data)
{
if (resultCode == RESULT_OK)
{
switch (requestCode)
{

case REQ_CARMER:

img.setImageBitmap(setImage(TEMP_PATH, new Intent()));

break;

}
}
super.onActivityResult(requestCode, resultCode, data);
}

}

不要忘了添加权限：

<uses-permission android:name="android.permission.CAMERA"></uses-permission>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"></uses-permission>