调用摄像头拍照，拿到缩略图，本地图，裁剪

通过两个按钮，分别拍照获取图片，第一个拿到的是缩略图，第二个是自己保存的图，直接上代码吧：

布局，

<?xml version="1.0" encoding="utf-8"?><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"   >    <Button        android:id="@+id/start_camera_thumbnail"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:onClick="takePhotoThumbnail"        android:text="拍照缩略图" />    <Button        android:id="@+id/start_camera"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:onClick="takePhotoLocal"        android:layout_below="@id/start_camera_thumbnail"        android:text="拍照本地图" />    <ImageView        android:id="@+id/image"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_centerInParent="true"        android:src="@mipmap/ic_launcher"        /></RelativeLayout>

Java 代码：

package com.example.myapplication;import android.content.Intent;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Matrix;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.View;import android.widget.Button;import android.widget.ImageView;import java.io.File;import java.io.IOException;public class MainActivity extends AppCompatActivity {    private ImageView imageView ;    private Uri imageUri ;    private  File outputIamge = null ;    private static final int TAKE_PHOTO_THUMBNAIL = 0 ;    private static final int TAKE_PHOTO_LOCAL = 1 ;    private static final int TAKE_CROP = 2;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        imageView = (ImageView)findViewById(R.id.image);    }    //拿到缩略图    public void takePhotoThumbnail(View view)    {        Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");        startActivityForResult(intent,TAKE_PHOTO_THUMBNAIL);    }    //本地图    public void takePhotoLocal(View view)    {        outputIamge = new File(Environment.getExternalStorageDirectory(),"photo.jpg");        try        {            if(outputIamge.exists())            {                outputIamge.delete();            }            outputIamge.createNewFile();        }catch (IOException e)        {            e.printStackTrace();        }        imageUri = Uri.fromFile(outputIamge);        Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");        intent.putExtra(MediaStore.EXTRA_OUTPUT,imageUri);        startActivityForResult(intent,TAKE_PHOTO_LOCAL);    }    @Override    protected void onActivityResult(int requestCode, int resultCode, Intent data) {        super.onActivityResult(requestCode, resultCode, data);       switch (requestCode) {           case TAKE_PHOTO_THUMBNAIL:               Bundle bundle = data.getExtras();               Bitmap bitmap = (Bitmap)bundle.get("data");               imageView.setImageBitmap(bitmap);               break;           case TAKE_PHOTO_LOCAL:               startPhotoZoom(Uri.fromFile(outputIamge));               break;           case TAKE_CROP:               Bitmap decodeFile = BitmapFactory.decodeFile(outputIamge.getAbsolutePath());               imageView.setImageBitmap(decodeFile);       }    }    //裁剪    public void startPhotoZoom(Uri uri) {        Intent intent = new Intent("com.android.camera.action.CROP");        intent.setDataAndType(uri, "image/*");        intent.putExtra("crop", "true");        intent.putExtra("aspectX", 1);        intent.putExtra("aspectY", 1);        intent.putExtra("outputX", 400);        intent.putExtra("outputY", 400);        intent.putExtra("scale", true);        intent.putExtra("return-data", false);        intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);        intent.putExtra("outputFormat", Bitmap.CompressFormat.PNG.toString());        intent.putExtra("noFaceDetection", true); // no face detection        startActivityForResult(intent, TAKE_CROP);    }}

1：拿缩略图，通过Bundle bundle = data.getExtras(); Bitmap bitMap = (Bitmap)bundle.get("data");就能拿到缩略图，一般这个不能满足需求。所以还是要拿原图。

2：通过 new File(Environment.getExternalStorageDirectory(),“photo.jpg”");，创建目录。最终拿到本地图片，并且展示（上面代码有）

最后，注册权限：

拍照权限：  <uses-permission android:name="android.permission.CAMERA"/>
 写到外部存储的权限    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

，ok了。