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Hi I am a PHP developer I want to do a simple thing - I want to draw something drawn on a blank page on an Android Phone (with a finger with a largeish "emulated pen nib") and store the bitmap as a jpeg on a server by http post.
Here is what I have so far but this is taken from a tutorial that is involved with writing sprites for a game.. And I cant' adapt it
package com.my.example;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnTouchListener;
public class DrawCapture extends Activity implements OnTouchListener{
OurView v;
Bitmap ball;
float x,y;
@Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.draw_capture);
v = new OurView(this);
v.setOnTouchListener(this);
ball = BitmapFactory.decodeResource(getResources(), R.drawable.blueball);
x = y = 0;
setContentView(v);
}
@Override
protected void onPause(){
super.onPause();
v.pause();
}
protected void onResume(){
super.onResume();
v.resume();
}
public class OurView extends SurfaceView implements Runnable{
Thread t = null;
SurfaceHolder holder;
boolean isItOK = false;
public OurView(Context context) {
super(context);
holder = getHolder();
}
public void run() {
while (isItOK == true){
try {
Thread.sleep(50);
} catch (InterruptedException e) {
e.printStackTrace();
}
//perform canvas drawing
if (!holder.getSurface().isValid()){
continue;
}
Canvas c = holder.lockCanvas();
onDraw(c);
holder.unlockCanvasAndPost(c);
}
}
public void onDraw(Canvas c){
c.drawARGB(255, 210, 210, 210);
c.drawBitmap(ball, x - (ball.getWidth()/2), y - (ball.getHeight()/2), null);
}
public void pause(){
isItOK = false;
while(true){
try{
t.join();
} catch(InterruptedException e){
e.printStackTrace();
}
break;
}
t = null;
}
public void resume(){
isItOK = true;
t = new Thread(this);
t.start();
}
}
public boolean onTouch(View v, MotionEvent me){
switch (me.getAction()){
case MotionEvent.ACTION_DOWN :
x = me.getX();
y = me.getY();
break;
case MotionEvent.ACTION_UP :
x = me.getX();
y = me.getY();
break;
case MotionEvent.ACTION_MOVE :
x = me.getX();
y = me.getY();
break;
}
return true;
}
}
and here is the XML
<?xml version="1.0" encoding="utf-8"?>
<SurfaceView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
</SurfaceView>
Can someone please help me? I feel I am close - I use the blueball as a pen nib I just want to "save" this and possibly I'll need to have a button (or menu) on the XML page to do this ? I know it's a bit of a beg but there are a lot of people online asking how to draw with your finger and save something to the "cloud" if people could respond with examples of the code (not references) I promise I will compile this into a proper tutorial piece of code for the eventual benefit of all. Including the PHP server side code that I already am really happy with.
You can try to use the Gesture Object proposed by Google, try to execute my following code :
Activity1 xml :
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#FFFFFF" >
<android.gesture.GestureOverlayView
android:id="@+id/gestures"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:fadeEnabled="false"
android:fadeOffset="5000000000"
android:gestureColor="#000000"
android:gestureStrokeType="multiple"
android:gestureStrokeWidth="1"
android:uncertainGestureColor="#000000"
android:layout_above="@+id/save_button" />
<Button
android:id="@id/save_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="20sp"
android:paddingLeft="20sp"
android:paddingRight="20sp"
android:text="Save"
android:textSize="22sp" />
</RelativeLayout>
Activity1 java :
package com.testandroidproject;
import java.io.ByteArrayOutputStream;
import android.app.Activity;
import android.content.Intent;
import android.gesture.GestureOverlayView;
import android.graphics.Bitmap;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;
public class Activity1 extends Activity {
private Button button_save;
private GestureOverlayView gesture;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
gesture = (GestureOverlayView) findViewById(R.id.gestures);
button_save = (Button) findViewById(R.id.save_button);
button_save.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
try {
Bitmap gestureImg = gesture.getGesture().toBitmap(100, 100,
8, Color.BLACK);
ByteArrayOutputStream bos = new ByteArrayOutputStream();
gestureImg.compress(Bitmap.CompressFormat.PNG, 100, bos);
byte[] bArray = bos.toByteArray();
Intent intent = new Intent(Activity1.this, Activity2.class);
intent.putExtra("draw", bArray);
startActivity(intent);
} catch (Exception e) {
e.printStackTrace();
Toast.makeText(Activity1.this, "No draw on the string",
3000).show();
}
}
});
}
}
Activity2 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:background="#FFFFFF"
android:orientation="vertical" >
<ImageView
android:id="@+id/image_saved"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal" />
</LinearLayout>
Activity2 java :
package com.testandroidproject;
import java.io.ByteArrayInputStream;
import android.app.Activity;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.widget.ImageView;
public class Activity2 extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.display_image);
ImageView image = (ImageView) findViewById(R.id.image_saved);
ByteArrayInputStream imageStreamClient = new ByteArrayInputStream(
getIntent().getExtras().getByteArray("draw"));
image.setImageBitmap(BitmapFactory.decodeStream(imageStreamClient));
}
}
Hope you will find this helpful.
I'm not sure what part of the "save" you are trying to accomplish, but I'll assume you're asking how to store what you've drawn on the canvas to a bitmap.
First, make yourself a bitmap to draw into. Say, canvasBitmap. Then:
c.setBitmap(canvasBitmap);
This will store everything that has been drawn into 'canvasBitmap.' Then, when the user presses a button to save:
savedBitmap = Bitmap.copy(canvasBitmap.getConfig(), true);
Now, take savedBitmap and fire it off into the cloud. Hope that helps.
来源：https://stackoverflow.com/questions/11631700/how-to-draw-something-with-your-finger-in-an-android-app-and-save-it-to-the