自定義surfaceview畫圖並儲存Canvas到DCIM
自定義surfaceview
package com.app.fantasticbaby;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.text.SimpleDateFormat;
import java.util.Date;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.media.MediaScannerConnection;
import android.net.Uri;
import android.os.Environment;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.Toast;
/**
* @author 作者 E-mail:
* @version 建立時間：2016-5-30 下午2:30:59
* 類說明
*/
public class MyView extends SurfaceView implements SurfaceHolder.Callback, OnTouchListener{
private Paint p = new Paint();
private Path path = new Path();
private Bitmap bi = Bitmap.createBitmap(400, 800, Config.ARGB_8888);
private SurfaceHolder holder = null;
private Canvas canvas = null;
private Canvas canvasTemp = null;
public MyView(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
holder = getHolder();
holder.addCallback(this);
p.setColor(Color.RED);
p.setTextSize(40);
p.setStrokeWidth(5);
p.setAntiAlias(true);
p.setFlags(Paint.ANTI_ALIAS_FLAG);
p.setStyle(Paint.Style.STROKE);
setOnTouchListener(this);
}
@Override
public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
// TODO Auto-generated method stub
}
@Override
public void surfaceCreated(SurfaceHolder arg0) {
// TODO Auto-generated method stub
bi = Bitmap.createBitmap(getWidth(), getHeight(),
Bitmap.Config.ARGB_8888);
canvasTemp = new Canvas(bi);
draw();
}
@Override
public void surfaceDestroyed(SurfaceHolder arg0) {
// TODO Auto-generated method stub
}
@Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
switch(event.getAction()){
case MotionEvent.ACTION_DOWN:
path.moveTo(event.getX(), event.getY());
draw();
break;
//不能將ACTION_DOWN裡的寫在ACTION_MOVE裡，不然會看不到畫出的軌跡
case MotionEvent.ACTION_MOVE: // 畫出每次移動的軌跡
case MotionEvent.ACTION_UP:
path.lineTo(event.getX(), event.getY());
draw();
break;
}
return true;
}
private void draw() {
try {
canvas = holder.lockCanvas();
if (holder != null) {
canvasTemp.drawColor(Color.WHITE);
canvasTemp.drawPath(path, p);
canvas.drawBitmap(bi, 0, 0, null);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (holder != null) {
holder.unlockCanvasAndPost(canvas);
}
}
}
private String getTime(){
return new SimpleDateFormat("HHmmssSSS").format(new Date(System.currentTimeMillis()));
}
//SurfaceView是不能截圖的，不過看了你程式碼發現不是這個原因造成的儲存不了圖片
//是canvas.setBitmap()的位置不對，畫完才設定Bitmap上去，肯定畫不出來
public void saveCanvas(View v){
//這樣雖然能夠儲存畫出的圖片，但是看不到SurfaceView了
//Canvas c = new Canvas(bi);
//c.drawColor(Color.WHITE);
//this.draw(c);
FileOutputStream fos = null;
String fileName = getTime();
String filePath = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM)+fileName+".png";
try {
fos = new FileOutputStream(new File(filePath));
bi.compress(Bitmap.CompressFormat.PNG, 100, fos);
MediaScannerConnection.scanFile(getContext(), new String[]{filePath}, null, new MediaScannerConnection.OnScanCompletedListener() {
@Override
public void onScanCompleted(String arg0, Uri arg1) {
// TODO Auto-generated method stub
Log.v("MediaScanWork", "file " + arg0
+ " was scanned seccessfully: " + arg1);
}
});
Toast.makeText(getContext(), "儲存成功,檔名:" + filePath + ".png", Toast.LENGTH_LONG).show();
clear();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void clear() {
// TODO Auto-generated method stub
path.reset();
draw();
}
}
實用activity
package com.app.fantasticbaby;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
/**
* @author 作者 E-mail:
* @version 建立時間：2016-5-30 下午3:01:23
* 類說明
*/
public class SurfaceActivity extends Activity {
private MyView myview;
private Button btn,save;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.surface_view);
myview = (MyView)findViewById(R.id.draw);
btn = (Button)findViewById(R.id.btn);
save = (Button)findViewById(R.id.save);
btn.setOnClickListener(new OnClickListener(){
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
myview.clear();
}
});
save.setOnClickListener(new OnClickListener(){
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
myview.saveCanvas(myview);
}
});
}
}
佈局：
<?xml version="1.0" encoding="UTF-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
>
<com.app.fantasticbaby.MyView
android:id="@+id/draw"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="1"
/>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
>
<Button
android:id="@+id/btn"
android:layout_weight="1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="清理"
/>
<Button
android:id="@+id/save"
android:layout_weight="1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="儲存"
/>
</LinearLayout>
</LinearLayout>
截圖：