我有2个表，一个用于成员，另一个用于他们的服务。这些是MySQL 5.6服务器上的InnoDB表。
会员表：
package com.example.androidsurfaceviewexample;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.NoSuchElementException;
import android.app.Activity;
import android.content.Intent;
import android.content.res.Configuration;
import android.hardware.Camera;
import android.hardware.Camera.PictureCallback;
import android.hardware.Camera.ShutterCallback;
import android.os.Bundle;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;
public class CameraActivity extends Activity implements SurfaceHolder.Callback {
TextView testView;
Camera camera;
SurfaceView surfaceView;
SurfaceHolder surfaceHolder;
PictureCallback rawCallback;
ShutterCallback shutterCallback;
PictureCallback jpegCallback;
public static boolean front = false;
Intent intent = null;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
intent = getIntent();
Bundle extras = intent.getExtras();
front = extras.getBoolean("front");
surfaceView = (SurfaceView) findViewById(R.id.surfaceView);
surfaceHolder = surfaceView.getHolder();
// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
surfaceHolder.addCallback(this);
// deprecated setting, but required on Android versions prior to 3.0
surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
jpegCallback = new PictureCallback() {
public void onPictureTaken(byte[] data, Camera camera) {
FileOutputStream outStream = null;
try {
String filePath=String.format("/sdcard/%d.jpg", System.currentTimeMillis());
outStream = new FileOutputStream(filePath);
outStream.write(data);
outStream.close();
FirstActivity.photo = true;
intent = new Intent(getBaseContext(), MainActivity.class);
Bundle extras = new Bundle();
//extras.putByteArray("path", data);
extras.putString("path", filePath);
extras.putString("front", "" + front);
intent.putExtras(extras);
startActivity(intent);
Log.d("Log", "onPictureTaken - wrote bytes: " + data.length);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
}
Toast.makeText(getApplicationContext(), "Picture Saved", 2000)
.show();
refreshCamera();
}
};
}
public void captureImage(View v) throws IOException {
// take the picture
camera.takePicture(null, null, jpegCallback);
}
public void refreshCamera() {
if (surfaceHolder.getSurface() == null) {
// preview surface does not exist
return;
}
// stop preview before making changes
try {
camera.stopPreview();
} catch (Exception e) {
// ignore: tried to stop a non-existent preview
}
// set preview size and make any resize, rotate or
// reformatting changes here
// start preview with new settings
if (this.getResources().getConfiguration().orientation != Configuration.ORIENTATION_LANDSCAPE) {
camera.setDisplayOrientation(90);
} else {
camera.setDisplayOrientation(0);
}
try {
camera.setPreviewDisplay(surfaceHolder);
camera.startPreview();
} catch (Exception e) {
}
}
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
// Now that the size is known, set up the camera parameters and begin
// the preview.
refreshCamera();
}
public void surfaceCreated(SurfaceHolder holder) {
try {
// open the camera
System.out.println("camera id"+""+getCamera());
if(front)
{
int frontExist=getCamera();
if(frontExist==1)
camera = getFrontFacingCamera();
else
camera = Camera.open();
}
else
camera = Camera.open();
} catch (RuntimeException e) {
// check for exceptions
System.err.println(e);
return;
}
// Camera.Parameters param;
// param = camera.getParameters();
// modify parameter
// param.setPreviewSize(352, 288);
// camera.setParameters(param);
try {
// The Surface has been created, now tell the camera where to draw
// the preview.
camera.setPreviewDisplay(surfaceHolder);
camera.startPreview();
} catch (Exception e) {
// check for exceptions
System.err.println(e);
return;
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// stop preview and release camera
camera.stopPreview();
camera.release();
camera = null;
}
Camera getFrontFacingCamera() throws NoSuchElementException {
Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
for (int cameraIndex = 0; cameraIndex < Camera.getNumberOfCameras(); cameraIndex++) {
Camera.getCameraInfo(cameraIndex, cameraInfo);
if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
try {
return Camera.open(cameraIndex);
} catch (RuntimeException e) {
e.printStackTrace();
}
}
}
throw new NoSuchElementException("Can't find front camera.");
}
int getCamera()
{
int f=0;
Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
for (int cameraIndex = 0; cameraIndex < Camera.getNumberOfCameras(); cameraIndex++) {
Camera.getCameraInfo(cameraIndex, cameraInfo);
if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
try {
f=1;
break;
} catch (RuntimeException e) {
e.printStackTrace();
}
}
else
f=0;
}
return f;
}
}
服务表：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.example.androidsurfaceviewexample.CameraActivity" >
<SurfaceView
android:id="@+id/surfaceView"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="0.66" />
<LinearLayout
android:id="@+id/capture"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clickable="true"
android:gravity="center"
android:onClick="captureImage"
android:orientation="horizontal" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center"
android:padding="10dp"
android:text="Capture"
android:textAppearance="?android:attr/textAppearanceLarge" />
</LinearLayout>
</LinearLayout>
我尝试实现这个结果：
id | name | phone
----------------------------------------
1 Daniel 123456789
2 Liam 123456789
3 Lucas 123456789
结果将取决于members.id = services.MID以及基于其services.category等于'35'的真或假。
答案 0 :(得分：2)
您可以使用left join和case when
select
m.id,
m.name,
case when s.MID is not null then 'true' else 'false' end as services
from members m
left join services s on s.MID = m.id and s.category = 35 ;