1.需要寫SD許可權

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

注意：
不需要<uses-permission android:name=“android.permission.CAMERA” />許可權，如果添加了，會報錯。

2.在佈局檔案中使用一個Button呼叫照相機，並顯示在一個ImageView中

activity_quickly_photo.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="zs.camerademo.QuicklyPhoto">
    <Button
        android:id="@+id/btn"
        android:text="拍照"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
    <ImageView
        android:id="@+id/iv"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
</LinearLayout>
 

3.在Activity:QuicklyPhoto.java中呼叫系統照相機

QuicklyPhoto.java

import android.Manifest;
import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.provider.MediaStore;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;

import java.io.File;
import java.io.FileOutputStream;
import java.util.UUID;

public class QuicklyPhoto extends AppCompatActivity implements View.OnClickListener{

    private ImageView iv;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_quickly_photo);
        findViewById(R.id.btn).setOnClickListener(this);
        iv = findViewById(R.id.iv);
        //獲取寫SD卡許可權
        if (ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE)
                == PackageManager.PERMISSION_GRANTED){
            System.out.println("OK");
        }else {
            ActivityCompat.requestPermissions(this,
                    new String[] {Manifest.permission.WRITE_EXTERNAL_STORAGE},1);
        }
    }

    @Override
    public void onClick(View v) {
        //用intent呼叫照相機拍照
        Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        startActivityForResult(intent,1);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        //設定iv為拍下的照片,並儲存到SD卡中
        if (requestCode == 1) {
            if (resultCode == Activity.RESULT_OK) {
                Bitmap cameraBitmap = (Bitmap) data.getExtras().get("data");
                iv.setImageBitmap(cameraBitmap);
                //儲存到sd卡中
                String name = "/sdcard/DCIM/"+ UUID.randomUUID()+".jpg";
                File pictureFile = new File(name);
                try {
                    FileOutputStream fos = new FileOutputStream(pictureFile);
                    //將bitmap轉換為png圖片
                    cameraBitmap.compress(Bitmap.CompressFormat.PNG,100,fos);
                    fos.flush();
                    fos.close();
                }catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
    }
}
 

效果如下：

點選拍照進入拍照介面

拍照完成

在SD卡中儲存了這張照片