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<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="cn.netkiller.camera">
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<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/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<provider
android:name="android.support.v4.content.FileProvider"
android:authorities="cn.netkiller.camera.provider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/provider_paths" />
</provider>
</application>
</manifest>
provider_paths.xml 文件
<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
<external-path name="external_files" path="."/>
</paths>
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.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">
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World!"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="@+id/buttonOpenCamera"
android:layout_width="160dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="8dp"
android:text="拍照立即显示"
app:layout_constraintBottom_toTopOf="@+id/buttonAlbum"
app:layout_constraintEnd_toStartOf="@+id/buttonSavePhoto"
app:layout_constraintHorizontal_bias="0.283"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/imageViewPicture"
app:layout_constraintVertical_bias="0.0" />
<Button
android:id="@+id/buttonSavePhoto"
android:layout_width="160dp"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:layout_marginEnd="20dp"
android:layout_marginBottom="8dp"
android:text="拍照存储后显示"
app:layout_constraintBottom_toTopOf="@+id/buttonAlbum"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toBottomOf="@+id/imageViewPicture"
app:layout_constraintVertical_bias="0.0" />
<ImageView
android:id="@+id/imageViewPicture"
android:layout_width="338dp"
android:layout_height="366dp"
android:layout_centerHorizontal="true"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView" />
<Button
android:id="@+id/buttonAlbum"
android:layout_width="352dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="8dp"
android:text="Album"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent" />
</android.support.constraint.ConstraintLayout>
package cn.netkiller.camera;
import android.Manifest;
import android.content.ContentResolver;
import android.content.ContentValues;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Environment;
import android.os.StrictMode;
import android.provider.MediaStore;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.FileProvider;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private ImageView imageViewPicture;
private Button buttonOpenCamera;
private Button buttonSavePhoto;
private Button buttonAlbum;
private static int REQUEST_CAMERA = 1;
private static int REQUEST_PHOTO = 2;
private static int REQUEST_ALBUM = 3;
private File imageFile;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imageViewPicture = (ImageView) findViewById(R.id.imageViewPicture);
buttonOpenCamera = (Button) findViewById(R.id.buttonOpenCamera);
buttonSavePhoto = (Button) findViewById(R.id.buttonSavePhoto);
buttonAlbum = (Button) findViewById(R.id.buttonAlbum);
buttonOpenCamera.setOnClickListener(this);
buttonSavePhoto.setOnClickListener(this);
buttonAlbum.setOnClickListener(this);
StrictMode.VmPolicy.Builder newbuilder = new StrictMode.VmPolicy.Builder();
StrictMode.setVmPolicy(newbuilder.build());
}
@Override
public void onClick(View view) {
Intent intent;
switch (view.getId()) {
case R.id.buttonOpenCamera:
// 拍照并显示图片
intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);// 启动系统相机
startActivityForResult(intent, REQUEST_CAMERA);
break;
case R.id.buttonSavePhoto:
if (!Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
TextView textView = (TextView) findViewById(R.id.textView);
textView.setText("SD 卡不存在，请插入 SD 卡！");
}
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
return;
} else {
String dir = Environment.getExternalStorageDirectory().getPath();
new File(dir).mkdirs();
imageFile = new File(dir, "tmp.png");
Uri imageUri = FileProvider.getUriForFile(MainActivity.this, "cn.netkiller.camera.provider", imageFile);
Log.d("album", imageFile.getPath());
intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);// 启动系统相机
intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
startActivityForResult(intent, REQUEST_PHOTO);
}
break;
case R.id.buttonAlbum:
intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(Intent.createChooser(intent, "Select Picture"), 3);
break;
default:
break;
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) { // 如果返回数据
if (requestCode == REQUEST_CAMERA) { // 判断请求码是否为REQUEST_CAMERA,如果是代表是这个页面传过去的，需要进行获取
Bundle bundle = data.getExtras(); // 从data中取出传递回来缩略图的信息，图片质量差，适合传递小图片
Bitmap bitmap = (Bitmap) bundle.get("data"); // 将data中的信息流解析为Bitmap类型
imageViewPicture.setImageBitmap(bitmap);// 显示图片
} else if (requestCode == REQUEST_PHOTO) {
Log.i("photo", imageFile.getPath());
try {
// InputStream inputStream = getContentResolver().openInputStream(imageUri);
String dir = Environment.getExternalStorageDirectory().getPath();
FileInputStream fileInputStream = new FileInputStream(imageFile);
Bitmap bitmap = BitmapFactory.decodeStream(fileInputStream);
fileInputStream.close();
imageViewPicture.setImageBitmap(bitmap);// 显示图片
} catch (Exception e) {
e.printStackTrace();
}
} else if (requestCode == REQUEST_ALBUM) {
Bitmap bitmap = null;
//外界的程序访问ContentProvider所提供数据 可以通过ContentResolver接口
ContentResolver resolver = getContentResolver();
Uri originalUri = data.getData(); //获得图片的uri
try {
bitmap = MediaStore.Images.Media.getBitmap(resolver, originalUri); //显得到bitmap图片
} catch (IOException e) {
e.printStackTrace();
}
//获取图片的路径：
Log.i("album", String.valueOf(originalUri));
imageViewPicture.setImageBitmap(bitmap);
}
}
}
}