我目前正在使用fingerpaint
处理画布绘图模块假设绘图笔的默认颜色为黑色。当通过HSVColor对话框选择颜色然后触摸屏幕时，所有先前绘制的颜色将更改为当前颜色而不是之前的路径黑色，最新的storke是已选择任何颜色。您能否告诉我修改onDraw Canvas或ACTION_DOWN的指导原则，以查看之前的笔触颜色是否未被覆盖
以下是我的代码
import java.io.File;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Calendar;
import com.galden.drawsth.asynctask.UploadImage;
import com.galden.drawsth.util.HSVColorPickerDialog;
import com.galden.drawsth.util.HSVColorPickerDialog.OnColorSelectedListener;
import com.galden.drawsth.util.SystemUtils;
import android.app.Activity;
import android.content.Context;
import android.content.ContextWrapper;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.RectF;
import android.os.Bundle;
import android.os.Environment;
import android.util.AttributeSet;
import android.util.Log;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.Toast;
public class MainActivity extends Activity {
private String sign;
LinearLayout mContent;
signature mSignature;
Button mClear, mGetSign, mCancel;
public static String tempDir;
public int count = 1;
public String current = null;
private Bitmap mBitmap;
View mView;
File mypath;
LinearLayout signlayout;
public static final int BUFFER_SIZE = 1024 * 8;
private ArrayList<Path> undonePaths = new ArrayList<Path>();
private ArrayList<Path> paths = new ArrayList<Path>();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
signlayout = (LinearLayout) findViewById(R.id.linearLayout1);
mContent = (LinearLayout) findViewById(R.id.linearLayout);
mSignature = new signature(getApplicationContext(), null);
mSignature.setBackgroundColor(Color.WHITE);
mContent.addView(mSignature, LayoutParams.FILL_PARENT,
LayoutParams.FILL_PARENT);
mView = mContent;
}
@Override
public void onDestroy() {
super.onDestroy();
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if( keyCode==KeyEvent.KEYCODE_BACK)
{
System.out.println("BACK");
return false;
}
else{
return super.onKeyDown(keyCode, event);
}
}
public class signature extends View {
private static final float STROKE_WIDTH = 10f;
private static final float HALF_STROKE_WIDTH = STROKE_WIDTH / 2;
private Canvas mCanvas;
private float mX;
private float mY;
private Bitmap bitmap; // drawing area for display or saving
private Path mPath;
private ArrayList<Path> paths = new ArrayList<Path>();
private ArrayList<Path> undonePaths = new ArrayList<Path>();
private static final float TOUCH_TOLERANCE = 4;
private Paint paint;
private final RectF dirtyRect = new RectF();
public signature(Context context, AttributeSet attrs) {
super(context, attrs);
initialisePen(Color.BLACK);
}
private void initialisePen(int color) {
// TODO Auto-generated method stub
paint = new Paint();
paint.setDither(true);
paint.setAntiAlias(true);
paint.setColor(color);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeWidth(STROKE_WIDTH);
paint.setStrokeCap(Paint.Cap.ROUND);
mCanvas = new Canvas();
mPath = new Path();
}
public void save(View v) {
if (mBitmap == null) {
mBitmap = Bitmap.createBitmap(mContent.getWidth(), mContent.getHeight(), Bitmap.Config.RGB_565);
}
Canvas canvas = new Canvas(mBitmap);
try {
v.draw(canvas);
String path = Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator + "CanvasTest";
File dir = new File(path);
if(!dir.exists()){
dir.mkdir();
}
Calendar c = Calendar.getInstance();
String date = c.get(Calendar.YEAR) + "-" + (c.get(Calendar.MONTH) + 1) + "-" + c.get(Calendar.DAY_OF_MONTH) + "-" + c.get(Calendar.HOUR_OF_DAY) + "-" + c.get(Calendar.MINUTE) + "-" + c.get(Calendar.SECOND);
String name = date + ".jpg";
File file = new File(dir.getAbsolutePath() + File.separator + name );
file.createNewFile();
FileOutputStream fos = new FileOutputStream(file);
final BufferedOutputStream bos = new BufferedOutputStream(fos, BUFFER_SIZE);
mBitmap.compress(CompressFormat.JPEG, 100, bos);
bos.flush();
bos.close();
fos.close();
Toast.makeText(getApplicationContext(), file.getName() + " is generated", Toast.LENGTH_SHORT).show();
mypath = file;
} catch (Exception e) {
e.printStackTrace();
}
}
public void clear() {
if (paths.size()>0)
{
paths.removeAll(paths);
invalidate();
}
invalidate();
}
public void colorChanged(int color) {
initialisePen(color);
}
@Override
protected void onDraw(Canvas canvas) {
for (Path p : paths) {
canvas.drawPath(p, paint);
}
canvas.drawPath(mPath, paint);
}
public boolean onTouchEvent(MotionEvent event)
{
float x = event.getX();
float y = event.getY();
switch (event.getAction())
{
case MotionEvent.ACTION_DOWN:
touch_start(x, y);
invalidate();
break;
case MotionEvent.ACTION_MOVE:
touch_move(x, y);
invalidate();
break;
case MotionEvent.ACTION_UP:
touch_up();
invalidate();
break;
}
return true;
}
private void touch_start(float x, float y)
{
undonePaths.clear();
mPath.reset();
mPath.moveTo(x, y);
mX = x;
mY = y;
}
private void touch_move(float x, float y)
{
float dx = Math.abs(x - mX);
float dy = Math.abs(y - mY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE)
{
mPath.quadTo(mX, mY, (x + mX)/2, (y + mY)/2);
mX = x;
mY = y;
}
}
private void touch_up()
{
mPath.lineTo(mX, mY);
mCanvas.drawPath(mPath, paint);// commit the path to our offscreen
paths.add(mPath);
mPath = new Path();
}
public void onClickUndo()
{
if (paths.size()>0)
{
undonePaths.add(paths.remove(paths.size()-1));
invalidate();
}
else Toast.makeText(getContext(), "nothing more to undo", Toast.LENGTH_SHORT).show();
}
}
@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
// Save the user's current game state
savedInstanceState.putString("signCanvas", sign);
// Always call the superclass so it can save the view hierarchy state
super.onSaveInstanceState(savedInstanceState);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main, menu);
return super.onCreateOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle presses on the action bar items
switch (item.getItemId()) {
case R.id.action_clear:
SystemUtils.toast(this, "Clear");
mSignature.clear();
//mGetSign.setEnabled(false);
return true;
case R.id.action_exit:
SystemUtils.toast(this, "Exit");
finish();
return true;
case R.id.action_undo:
SystemUtils.toast(this, "Undo");
mSignature.onClickUndo();
return true;
case R.id.action_save:
SystemUtils.toast(this, "Save");
mView.setDrawingCacheEnabled(true);
mSignature.save(mView);
return true;
case R.id.action_upload:
SystemUtils.toast(this, "Upload");
mView.setDrawingCacheEnabled(true);
mSignature.save(mView);
new UploadImage(MainActivity.this).execute(mypath);
return true;
case R.id.action_select:
HSVColorPickerDialog cpd = new HSVColorPickerDialog( MainActivity.this, 0xFF4488CC, new OnColorSelectedListener() {
@Override
public void colorSelected(Integer color) {
// Do something with the selected color
mSignature.colorChanged(color);
}
});
cpd.setTitle( "Pick a color" );
cpd.setNoColorButton( R.string.no_color );
cpd.show();
return true;
/*case R.id.action_setting:
SystemUtils.toast(this, "Setting");
return true;*/
default:
return super.onOptionsItemSelected(item);
}
}
}