[移动开发]【安卓开发】调用手机的相机进行拍照并且保存在本地的APP

官网文档

拍照功能

点击拍照后可以进行拍照，并且将得到的照片展现在屏幕上

添加相机权限

<uses-feature android:name="android.hardware.camera"
        android:required="true" />

JAVA代码

package Picture;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.graphics.Bitmap;
import android.media.Image;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.widget.ImageView;

import com.example.myapp_b.R;

public class MainActivity extends AppCompatActivity {
    ImageView imageView;
    static final int REQUEST_IMAGE_CAPTURE=1;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        imageView=findViewById(R.id.iv);
    }

    public void takePic(View view) {
        Intent intent=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        if(intent.resolveActivity(getPackageManager())!=null){
            startActivityForResult(intent,REQUEST_IMAGE_CAPTURE);
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
            Bundle extras = data.getExtras();
            Bitmap imageBitmap = (Bitmap) extras.get("data");
            imageView.setImageBitmap(imageBitmap);
        }
    }

}

XML代码

<?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"
    tools:context="Picture.MainActivity"
    android:orientation="vertical">
    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="拍照"
        android:onClick="takePic"
        ></Button>
    <ImageView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/iv"></ImageView>
</LinearLayout>

保存到本地

package Picture;

import androidx.appcompat.app.AppCompatActivity;
import androidx.core.content.FileProvider;

import android.content.Intent;
import android.graphics.Bitmap;
import android.media.Image;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.view.View;
import android.widget.ImageView;

import com.example.myapp_b.R;

import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;

public class MainActivity extends AppCompatActivity {
    ImageView imageView;
    static final int REQUEST_IMAGE_CAPTURE=1;
    static final int RESULT_OK=-1;
    String path="";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        imageView=findViewById(R.id.iv);
    }

    public void takePic(View view) throws IOException {
        Intent intent=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);//开启系统相机的意图对象
        String imagePath= Environment.getExternalStorageDirectory()+"/DCIM";//设置照片保存路径
        File file=new File(imagePath, "default_image.jpg");
        //File file=createImageFile();
        path=file.getAbsolutePath();
        //使用文件提供者获取路径URL
        Uri contentUri= FileProvider.getUriForFile(this,"com.example.android.fileprovider",file);
        //设置传递参数 让相机拍照后保存照片
        intent.putExtra(MediaStore.EXTRA_OUTPUT,contentUri);
        startActivityForResult(intent,1);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
            //1.设置扫描意图
            Intent mediaScanIntent=new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
            //2.设置路径
            File f=new File(path);
            //3.获取路径
            Uri contenturi=Uri.fromFile(f);//file:///storage/emulated/0/DCIM/default_image.jpg
            mediaScanIntent.setData(contenturi);
            System.out.println(contenturi.toString());
            //4.发送广播
            this.sendBroadcast(mediaScanIntent);
//            Bundle extras = data.getExtras();
//            Bitmap imageBitmap = (Bitmap) extras.get("data");
//            imageView.setImageBitmap(imageBitmap);
        }
    }
    private File createImageFile() throws IOException {
        // 创建独一无二的文件名
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
        String imageFileName = "JPEG_" + timeStamp + "_";
        File storageDir = getExternalFilesDir(Environment.DIRECTORY_PICTURES);
        File image = File.createTempFile(
                imageFileName,  /* prefix */
                ".jpg",         /* suffix */
                storageDir      /* directory */
        );

        // Save a file: path for use with ACTION_VIEW intents
        path = image.getAbsolutePath();
        return image;
    }

}

配置文件

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="com.example.myapp_b">
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-feature android:name="android.hardware.camera" android:required="false" />
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.Myapp_b">
        <activity
            android:name="Picture.MainActivity"
            android:exported="true" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>

        </activity>
        <activity
            android:name=".MainActivity"
            android:exported="true">

        </activity>
        <provider
            android:name="androidx.core.content.FileProvider"
            android:authorities="com.example.android.fileprovider"
            android:exported="false"
            android:grantUriPermissions="true"
            tools:ignore="WrongManifestParent">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/file_path"></meta-data>
        </provider>
    </application>
</manifest>

file_path.xml

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="my_images" path="DCIM" />
</paths>

不重复文件名

上述方法得到的文件名是重复的，参考官网文档可以将其的名字加上时间

String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
File file=new File(imagePath, "JPEG_" + timeStamp + ".jpg");