MainActivity.java
import android.Manifest;
import android.content.ContentUris;
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.Build;
import android.os.Bundle;
import android.provider.DocumentsContract;
import android.provider.MediaStore;
import android.support.annotation.RequiresApi;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v4.content.FileProvider;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
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 csdn.example.com.notification.R;
public class Main2Activity extends AppCompatActivity {
public static final int TAKEPHOTO = 1;
public static final int CHOOSE_PHOTO = 2;
private ImageView picture;
private Uri imageUri;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
//拍照片按钮
Button takePhoto = (Button) findViewById(R.id.take_photo);
//从相册中选照片按钮
Button ChooseFromAlbum = (Button) findViewById(R.id.choose_from_album);
picture = (ImageView) findViewById(R.id.picture);
takePhoto.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//创建File对象，用于存储拍照后的照片
File outputImage = new File(getExternalCacheDir(),
"output_image.jpg");
try {
if(outputImage.exists()){
outputImage.delete();
}
outputImage.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
if(Build.VERSION.SDK_INT >= 24){
imageUri = FileProvider.getUriForFile(Main2Activity.this,
"csdn.example.com.notification.CameraAlbumTest",outputImage);
}else {
imageUri = Uri.fromFile(outputImage);
}
//启动相机程序
Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
intent.putExtra(MediaStore.EXTRA_OUTPUT,imageUri);
startActivityForResult(intent,TAKEPHOTO);
}
});
ChooseFromAlbum.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(ContextCompat.checkSelfPermission(Main2Activity.this,
Manifest.permission.WRITE_EXTERNAL_STORAGE)!= PackageManager.PERMISSION_GRANTED){
ActivityCompat.requestPermissions(Main2Activity.this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},1);
}else {
openAlbum();
}
}
});
}
/**
* 功能：打开相册
*/
private void openAlbum() {
//动态申请write_external_storage这个危险权限
Intent intent = new Intent("android.intent.action.GET_CONTENT");
intent.setType("image/*");
startActivityForResult(intent,CHOOSE_PHOTO); //打开相机
Log.d("Picture","1");
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
switch (requestCode){
case 1:
if(grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED){
openAlbum();
}else {
Toast.makeText(this,"你否认了许可",Toast.LENGTH_SHORT).show();
}
break;
default:
}
}
/**
* 对封装过的Uri进行解析
* @param data
*/
@RequiresApi(api = Build.VERSION_CODES.KITKAT)
private void handlerImageOnKitKat(Intent data) {
Log.d("Picture","2");
String imagePath = null;
Uri uri = data.getData();
if(DocumentsContract.isDocumentUri(this,uri)){
//如果是document类型的Uri,则通过document id 处理
String docId = DocumentsContract.getDocumentId(uri);
//如果Uri的authority是media格式的话，还需要进一步解析
if("com.android.providers.media.documents".equals(uri.getAuthority())){
//通过字符串分割取出后半部分才能得到真正的数字
String id = docId.split(":")[1]; //解析出数字格式的id
//重新构建和条件语句
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 contentUri = ContentUris.withAppendedId(Uri.parse("content://download.public_downloads"),Long.valueOf(docId));
imagePath = getImagePath(contentUri,null);
}
}else if("content".equalsIgnoreCase(uri.getScheme())){
//如果是content类型的Uri ,则使用普通方式处理
imagePath = getImagePath(uri,null);
}else if("file".equalsIgnoreCase(uri.getScheme())){
//如果是file类型的Uri，直接获取图片路径即可
imagePath = uri.getPath();
}
dispalyImage(imagePath); //根据图片路径显示图片
}
private void handleImageBeforeKitkat(Intent data){
Log.d("Picture","3");
Uri uri = data.getData();
String imagePath = getImagePath(uri,null);
dispalyImage(imagePath);
}
/**
* 获得图片真实路径
* @param uri
* @param selection
* @return
*/
private String getImagePath(Uri uri, String selection) {
Log.d("Picture","得到照片");
String path = null;
//通过Uri 和 selection获得真实的图片路径
Cursor cursor = getContentResolver().query(uri,null,selection,null,null);
if(cursor != null){
if(cursor.moveToFirst()){
path = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA));
}
cursor.close();
}
return path;
}
/**
* 函数名称：dispalyImage
* 返回值类型：无参
* 传入的参数：imagePath
* 传出的参数：无
* 功能：将图片显示到街面上
* @param imagePath
*/
private void dispalyImage(String imagePath) {
Log.d("Picture","拿到照片了吗？"+imagePath);
if(imagePath != null){
Log.d("Picture","拿到照片了吗？");
Toast.makeText(this,"你成功的打开了图片",Toast.LENGTH_SHORT).show();
Bitmap bitmap = BitmapFactory.decodeFile(imagePath);
picture.setImageBitmap(bitmap);
Log.d("Picture","拿到照片了ba？");
}else {
Toast.makeText(this,"failed to get image",Toast.LENGTH_SHORT).show();
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode){
case TAKEPHOTO:
if(resultCode == RESULT_OK){
Log.d("Picture","到这里了没有1111？");
try {
//将拍摄照片显示出来
Bitmap bitmap = BitmapFactory.decodeStream(getContentResolver().openInputStream(imageUri));
picture.setImageBitmap(bitmap);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
break;
case CHOOSE_PHOTO:
Log.d("Picture","到这里了没有？");
if(resultCode == RESULT_OK){
Log.d("Picture","？？？2222");
//判断手机系统版本
if(Build.VERSION.SDK_INT >= 19){
//4.4及以上系统使用这个方法处理图片
handlerImageOnKitKat(data);
}else {
//4.4以下系统使用这个方法处理图片
handleImageBeforeKitkat(data);
}
}
break;
default:
break;
}
super.onActivityResult(requestCode, resultCode, data);
}
}
activity_main.xml
-----------------
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<Button
android:id="@+id/take_photo"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="拍照片" />
<ImageView
android:id="@+id/picture"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal" />
<Button
android:id="@+id/choose_from_album"
android:text="从相册里打开照片"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>运行图片如下
拍照
从相册选择照片
清单文件
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="csdn.example.com.notification">
<uses-permission android:name="android.permission.VIBRATE" />
<uses-permission android:name="android.permission.BIND_NOTIFICATION_LISTENER_SERVICE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<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">
<provider
android:authorities="csdn.example.com.notification.CameraAlbumTest"
android:name="android.support.v4.content.FileProvider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/file_paths"/>
</provider>
<activity android:name=".CameraAlbumTest.Main2Activity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>