从拍照，相册中获取图片
直接上代码吧
示例代码
申请权限
AndroidManifest.xml
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
activity_camera.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"
tools:context=".chapter08.CameraActivity"
android:orientation="vertical">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<Button
android:id="@+id/btn_c_use_camera"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="使用相机拍照" />
<Button
android:id="@+id/btn_c_use_lib"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="从相册选取" />
<ImageView
android:id="@+id/iv_c_image"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
</ScrollView>
</LinearLayout>
CameraActivity.java
public class CameraActivity extends AppCompatActivity {
private static final int TAKE_PHOTO = 1;
private static final int CHOOSE_PHOTO = 2;
private ImageView iv_c_image;
private Uri imageUri;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_camera);
iv_c_image = findViewById(R.id.iv_c_image);
// 使用相机拍照
Button btn_c_use_camera = findViewById(R.id.btn_c_use_camera);
btn_c_use_camera.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// 创建一个文件去接收图片
File outputImage = new File(getExternalCacheDir(), "output_image.jpg");
try {
// 存在该文件删除
if (outputImage.exists()) {
outputImage.delete();
}
outputImage.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
// 获取该文件的uri
if (Build.VERSION.SDK_INT >= 24) {
imageUri = FileProvider.getUriForFile(CameraActivity.this,
"com.bl.blandroidpro.fileprovider", outputImage);
} else {
imageUri = Uri.fromFile(outputImage);
}
// 创建打开相机意图
Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
// 用此文件接收拍照后的图片
intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
// 打开相机
startActivityForResult(intent, TAKE_PHOTO);
}
});
// 从相册选取
Button btn_c_use_lib = findViewById(R.id.btn_c_use_lib);
btn_c_use_lib.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// 请求权限
if (ContextCompat.checkSelfPermission(CameraActivity.this,
Manifest.permission.WRITE_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(CameraActivity.this,
new String[] {Manifest.permission.WRITE_EXTERNAL_STORAGE}
, 1);
} else {
openAlbum();
}
}
});
}
public void openAlbum() {
// 创建打开相册意图
Intent intent = new Intent("android.intent.action.GET_CONTENT");
// 设置获取类型
intent.setType("image/*");
// 打开相册
startActivityForResult(intent, CHOOSE_PHOTO);
}
/**
* 请求权限回调
* @param requestCode
* @param permissions
* @param grantResults
*/
@Override
public void onRequestPermissionsResult(
int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
switch (requestCode) {
case 1:
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
openAlbum();
} else {
Toast.makeText(this,
"You denied the permission", Toast.LENGTH_LONG).show();
}
break;
default:
break;
}
}
/**
* 关闭相机或相册回调
* @param requestCode
* @param resultCode
* @param data
*/
@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
switch (requestCode) {
case TAKE_PHOTO:
if (resultCode == RESULT_OK) {
try {
// 获取刚拍好图片
Bitmap bitmap = BitmapFactory.decodeStream(
getContentResolver().openInputStream(imageUri));
iv_c_image.setImageBitmap(bitmap);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
break;
case CHOOSE_PHOTO:
if (resultCode == RESULT_OK) {
// Android 4.4以上 使用这个方法处理图片
if (Build.VERSION.SDK_INT >= 19) {
handleImageOnKitKat(data);
// Android 4.4以下 使用这个方法处理图片
} else {
handleImageBeforeKitKat(data);
}
}
break;
default:
break;
}
}
/**
* Android 4.4+
* @param data
*/
@TargetApi(19)
private void handleImageOnKitKat(Intent data) {
String imagePath = null;
Uri uri = data.getData();
// 如果是 document 类型的 Uri，则通过 document id 处理
if (DocumentsContract.isDocumentUri(this, uri)) {
String docId = DocumentsContract.getDocumentId(uri);
if ("com.android.providers.media.documents".equals(uri.getAuthority())) {
// 解析出数字格式的id
String id = docId.split(":")[1];
String selection = MediaStore.Images.Media._ID + "=" + id;
imagePath = getImagePath(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, selection);
} else if ("com.android.providers.downloads.documents".equals(uri.getAuthority())) {
Uri contetnUri = ContentUris.withAppendedId(
Uri.parse("content://downloads/public_downloads"), Long.valueOf(docId));
imagePath = getImagePath(contetnUri, null);
}
// 如果是 content 类型的Uri，则使用普通方式处理
} else if ("content".equalsIgnoreCase(uri.getScheme())) {
imagePath = getImagePath(uri, null);
// 如果是 file 类型的 Uri，直接截取图片路径
} else if ("file".equalsIgnoreCase(uri.getScheme())) {
imagePath = uri.getPath();
}
// 根据图片路径显示
displayImage(imagePath);
}
/**
* Android 4.4-
* @param data
*/
private void handleImageBeforeKitKat(Intent data) {
Uri uri = data.getData();
String imagePath = getImagePath(uri,null);
displayImage(imagePath);
}
private String getImagePath(Uri uri, String selection) {
String path = null;
// 通过 Uri 和 Selection 来获取真是的图片路径
Cursor cursor = getContentResolver().query(uri,
null, selection, null, null);
if (cursor != null) {
if (cursor.moveToNext()) {
path = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA));
}
cursor.close();
}
return path;
}
private void displayImage(String imagePath) {
if (imagePath != null) {
Bitmap bitmap = BitmapFactory.decodeFile(imagePath);
iv_c_image.setImageBitmap(bitmap);
} else {
Toast.makeText(this,
"failed to get image", Toast.LENGTH_LONG).show();
}
}
}
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