我的Android笔记(五)——调用相机并将照片存储到sd卡上
Android中实现拍照有两种方法,一种是调用系统自带的相机,然后使用其返回的照片数据。 还有一种是自己用Camera类和其他相关类实现相机功能,这种方法定制度比较高,洗染也比较复杂,一般平常的应用只需使用第一种即可。
用Intent启动相机的代码:
[java]
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(intent, 1);
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(intent, 1);
拍完照后就可以在onActivityResult(int requestCode, int resultCode, Intent data)中获取到Bitmap对象了。
[java]
Bitmap bitmap = (Bitmap) data.getExtras().get("data");
Bitmap bitmap = (Bitmap) data.getExtras().get("data");
要将图像存储到sd卡之前最好先检查一下sd卡是否可用
[java]
String sdStatus = Environment.getExternalStorageState();
if (!sdStatus.equals(Environment.MEDIA_MOUNTED)) { // 检测sd是否可用
Log.v("TestFile",
"SD card is not avaiable/writeable right now.");
return;
}
String sdStatus = Environment.getExternalStorageState();
if (!sdStatus.equals(Environment.MEDIA_MOUNTED)) { // 检测sd是否可用
Log.v("TestFile",
"SD card is not avaiable/writeable right now.");
return;
}
以下代码可以实现将图像文件存到“sdcard/myImage/”文件夹下,名称为“111.jpg”
[java]
File file = new File("/sdcard/myImage/");
file.mkdirs();// 创建文件夹
String fileName = "/sdcard/myImage/111.jpg";
try {
b = new FileOutputStream(fileName);
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, b);// 把数据写入文件
} catch (FileNotFoundException e) {
e.printStackTrace();
} finally {
try {
b.flush();
b.close();
} catch (IOException e) {
e.printStackTrace();
}
}
File file = new File("/sdcard/myImage/");
file.mkdirs();// 创建文件夹
String fileName = "/sdcard/myImage/111.jpg";
try {
b = new FileOutputStream(fileName);
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, b);// 把数据写入文件
} catch (FileNotFoundException e) {
e.printStackTrace();
} finally {
try {
b.flush();
b.close();
} catch (IOException e) {
e.printStackTrace();
}
}另外要注意的是读写sd卡文件必须首先要在Mainifest.xml文件中配置权限:
[html]
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
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一个demo,实现调用系统相机拍照,将其显示在屏幕上,并且存到sd卡。
完整代码如下:
MyCaremaActivity.java
[java]
package barry.android.c;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
public class MyCaremaActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(intent, 1);
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == Activity.RESULT_OK) {
String sdStatus = Environment.getExternalStorageState();
if (!sdStatus.equals(Environment.MEDIA_MOUNTED)) { // 检测sd是否可用
Log.v("TestFile",
"SD card is not avaiable/writeable right now.");
return;
}
Bundle bundle = data.getExtras();
Bitmap bitma
补充:移动开发 , Android ,