Android调用手机摄像头的方法
本文实例为大家分享了Android调用手机摄像头的具体代码，供大家参考，具体内容如下
根据<第一行代码>进行改写：
布局文件，只有一个按钮，和一个Imageview,imageview用于显示拍下后的图片
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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=".MainActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/take_photo"
android:text="Take Photo"/>
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:id="@+id/picture"/>
</LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
MainActivity.java
package com.example.choosepictest;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.content.ContextCompat;
import androidx.core.content.FileProvider;
import android.Manifest;
import android.app.Activity;
import android.content.ContentValues;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Camera;
import android.graphics.Matrix;
import android.media.ExifInterface;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.view.View;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
public class MainActivity extends AppCompatActivity {
public static final int TAKE_PHOTO=1;
private Button takePhoto;
private ImageView picture;
private Uri imageUri;
public static File tempFile;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
takePhoto = (Button) findViewById(R.id.take_photo);
picture = (ImageView) findViewById(R.id.picture);
takePhoto.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
tempFile=new File(getExternalCacheDir(),"output_image.jpg");
if(tempFile.exists())
{
tempFile.delete();
}
try {
tempFile.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
if(Build.VERSION.SDK_INT>=Build.VERSION_CODES.N)
{
imageUri= FileProvider.getUriForFile(MainActivity.this,
"com.example.choosepictest.fileprovider",tempFile);
}else{
Uri.fromFile(tempFile);
}
Intent intent=new Intent("android.media.action.IMAGE_CAPTURE");
intent.putExtra(MediaStore.EXTRA_OUTPUT,imageUri);
startActivityForResult(intent,TAKE_PHOTO);
}
});
}
protected void onActivityResult(int requestCode,int resultCode,Intent data)
{
super.onActivityResult(requestCode,requestCode,data);
switch (requestCode)
{
case TAKE_PHOTO:
if(resultCode==Activity.RESULT_OK)
{
Bitmap bitmap= null;
try {
bitmap = BitmapFactory.decodeStream(getContentResolver()
.openInputStream(imageUri));
} catch (FileNotFoundException e) {
e.printStackTrace();
}
picture.setImageBitmap(rotateIfRequired(bitmap));
}
break;
default:
break;
}
}
private Bitmap rotateIfRequired(Bitmap bitmap)
{
String path=tempFile.getPath();
ExifInterface exif = null;
try {
exif=new ExifInterface(path);
} catch (IOException e) {
e.printStackTrace();
}
int orientation= exif.getAttributeInt(ExifInterface.TAG_EXIF_VERSION,
ExifInterface.ORIENTATION_NORMAL);
switch (orientation)
{
case ExifInterface.ORIENTATION_ROTATE_90:
bitmap=rotateBitmap(bitmap,90);
break;
case ExifInterface.ORIENTATION_ROTATE_180:
bitmap=rotateBitmap(bitmap,180);
break;
case ExifInterface.ORIENTATION_ROTATE_270:
bitmap=rotateBitmap(bitmap,270);
break;
default:
break;
}
return bitmap;
}
private Bitmap rotateBitmap(Bitmap bitmap,int degree)
{
Matrix matrix=new Matrix();
matrix.postRotate((float)degree);
Bitmap rotateBitmap=Bitmap.createBitmap(bitmap,0,0,
bitmap.getWidth(),bitmap.getHeight(),matrix,true);
bitmap.recycle();
return bitmap;
}
}
活动管理(mainfest)：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.choosepictest">
<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.ChoosePicTest">
<activity
android:name=".MainActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<provider
android:authorities="com.example.choosepictest.fileprovider"
android:name="androidx.core.content.FileProvider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/file_paths"/>
</provider>
</application>
</manifest>
用于指定路径file_paths.xml：
<?xml version="1.0" encoding="utf-8" ?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
<external-path
name="my_images"
path="/"/>
</paths>
效果图：
这是虚拟机，所以啥也看不到，真机就可以看到了。
