android - 如何在 Android 应用程序中用手指画画……并将其保存到网络

Question

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您好，我是一名 PHP 开发人员，我想做一件简单的事情 - 我想在 Android 手机的空白页上绘制一些东西(用带有较大“模拟 Nib ”的手指)并将位图存储为通过 http post 在服务器上生成 jpeg。

这是我目前所拥有的，但这是取自 a tutorial这与为游戏编写 Sprite 有关。我无法适应它

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;
    }
}

这是 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>

有人可以帮帮我吗？我觉得我很接近 - 我使用 blueball 作为 Nib 我只是想“保存”这个并且可能我需要在 XML 页面上有一个按钮(或菜单)来执行此操作？我知道这有点勉强，但是网上有很多的人询问如何用手指画画并将某些东西保存到“云”中，如果人们可以用代码示例(不是引用)来回应的话) 我保证我会把它编译成一段适当的教程代码，以造福于所有人。包括我已经非常满意的 PHP 服务器端代码。

Answer 1

你可以尝试使用Google提出的Gesture Object，尝试执行我下面的代码:

Activity 1 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));
    }

}

希望这对您有所帮助。