在我的Android应用程序用户中，在我的应用程序中的表单中进行签名。签名必须编辑，更清楚，保存。我确实保存并清除。但编辑不起作用我使用下面的代码
mContent = (LinearLayout) findViewById(R.id.linearLayout);
mSignature = new signature(this, null);
mSignature.setBackgroundColor(Color.WHITE);
mContent.addView(mSignature, LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT);
mClear = (Button)findViewById(R.id.clear);
mGetSign = (Button)findViewById(R.id.getsign);
mGetSign.setEnabled(false);
mCancel = (Button)findViewById(R.id.cancel);
mView = mContent;
mClear.setOnClickListener(new OnClickListener()
{
public void onClick(View v)
{
Log.v("log_tag", "Panel Cleared");
mSignature.clear();
mGetSign.setEnabled(false);
}
});
mGetSign.setOnClickListener(new OnClickListener()
{
public void onClick(View v)
{
Log.v("log_tag", "Panel Saved");
mView.setDrawingCacheEnabled(true);
mSignature.save(mView);
Bundle b = new Bundle();
b.putString("status", "done");
b.putParcelable("data", mBitmap);
Intent intent = new Intent();
intent.putExtras(b);
setResult(RESULT_OK,intent);
finish();
}
});
mCancel.setOnClickListener(new OnClickListener()
{
public void onClick(View v)
{
Log.v("log_tag", "Panel Canceled");
Bundle b = new Bundle();
b.putString("status", "cancel");
Intent intent = new Intent();
intent.putExtras(b);
setResult(RESULT_OK,intent);
finish();
}
});
}
@Override
protected void onDestroy() {
Log.w("GetSignature", "onDestory");
super.onDestroy();
}
public class signature extends View
{
private static final float STROKE_WIDTH = 5f;
private static final float HALF_STROKE_WIDTH = STROKE_WIDTH / 2;
private Paint paint = new Paint();
private Path path = new Path();
private float lastTouchX;
private float lastTouchY;
private final RectF dirtyRect = new RectF();
public signature(Context context, AttributeSet attrs)
{
super(context, attrs);
paint.setAntiAlias(true);
paint.setColor(Color.BLACK);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeWidth(STROKE_WIDTH);
}
public void save(View v)
{
Log.v("log_tag", "Width: " + v.getWidth());
Log.v("log_tag", "Height: " + v.getHeight());
if(mBitmap == null)
{
mBitmap = Bitmap.createBitmap (mContent.getWidth(), mContent.getHeight(), Bitmap.Config.RGB_565);;
}
Canvas canvas = new Canvas(mBitmap);
try
{
FileOutputStream mFileOutStream = new FileOutputStream(mypath);
v.draw(canvas);
mBitmap.compress(Bitmap.CompressFormat.PNG, 90, mFileOutStream);
mFileOutStream.flush();
mFileOutStream.close();
// String url = Images.Media.insertImage(getContentResolver(), mBitmap, "title", null);
// Log.v("log_tag","url: " + url);
//In case you want to delete the file
//boolean deleted = mypath.delete();
//Log.v("log_tag","deleted: " + mypath.toString() + deleted);
//If you want to convert the image to string use base64 converter
}
catch(Exception e)
{
Log.v("log_tag", e.toString());
}
}
public void clear()
{
path.reset();
invalidate();
}
@Override
protected void onDraw(Canvas canvas)
{
canvas.drawPath(path, paint);
}
@Override
public boolean onTouchEvent(MotionEvent event)
{
float eventX = event.getX();
float eventY = event.getY();
mGetSign.setEnabled(true);
switch (event.getAction())
{
case MotionEvent.ACTION_DOWN:
path.moveTo(eventX, eventY);
lastTouchX = eventX;
lastTouchY = eventY;
return true;
case MotionEvent.ACTION_MOVE:
case MotionEvent.ACTION_UP:
resetDirtyRect(eventX, eventY);
int historySize = event.getHistorySize();
for (int i = 0; i < historySize; i++)
{
float historicalX = event.getHistoricalX(i);
float historicalY = event.getHistoricalY(i);
expandDirtyRect(historicalX, historicalY);
path.lineTo(historicalX, historicalY);
}
path.lineTo(eventX, eventY);
break;
default:
debug("Ignored touch event: " + event.toString());
return false;
}
invalidate((int) (dirtyRect.left - HALF_STROKE_WIDTH),
(int) (dirtyRect.top - HALF_STROKE_WIDTH),
(int) (dirtyRect.right + HALF_STROKE_WIDTH),
(int) (dirtyRect.bottom + HALF_STROKE_WIDTH));
lastTouchX = eventX;
lastTouchY = eventY;
return true;
}
private void debug(String string){
}
private void expandDirtyRect(float historicalX, float historicalY)
{
if (historicalX < dirtyRect.left)
{
dirtyRect.left = historicalX;
}
else if (historicalX > dirtyRect.right)
{
dirtyRect.right = historicalX;
}
if (historicalY < dirtyRect.top)
{
dirtyRect.top = historicalY;
}
else if (historicalY > dirtyRect.bottom)
{
dirtyRect.bottom = historicalY;
}
}
private void resetDirtyRect(float eventX, float eventY)
{
dirtyRect.left = Math.min(lastTouchX, eventX);
dirtyRect.right = Math.max(lastTouchX, eventX);
dirtyRect.top = Math.min(lastTouchY, eventY);
dirtyRect.bottom = Math.max(lastTouchY, eventY);
}
}
答案 0 :(得分：4)
这个自定义视图可能会有所帮助。在您的XML中，只需使用me.other.SignatureView
package me.other;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.os.SystemClock;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
/**
* A simple view to capture a path traced onto the screen. Initially intended to be used to captures signatures.
*
* @author Andrew Crichton
* @version 0.1
*/
public class SignatureView extends View {
@SuppressWarnings("unused")
private Path mPath;
private Paint mPaint;
private Paint bgPaint = new Paint(Color.TRANSPARENT);
private Bitmap mBitmap;
private Canvas mCanvas;
private float curX, curY;
private static final int TOUCH_TOLERANCE = 4;
private static final int STROKE_WIDTH = 4;
public SignatureView(Context context) {
super(context);
init();
}
public SignatureView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public SignatureView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private void init() {
setFocusable(true);
mPath = new Path();
mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mPaint.setColor(Color.WHITE);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeWidth(STROKE_WIDTH);
}
public void setSigColor(int color) {
mPaint.setColor(color);
}
public void setSigColor(int a, int red, int green, int blue) {
mPaint.setARGB(a, red, green, blue);
}
public boolean clearSignature() {
if (mBitmap != null)
createFakeMotionEvents();
if (mCanvas != null) {
mCanvas.drawColor(Color.BLACK);
mCanvas.drawPaint(bgPaint);
mPath.reset();
invalidate();
}
else {
return false;
}
return true;
}
public Bitmap getImage() {
return this.mBitmap;
}
public void setImage(Bitmap bitmap) {
this.mBitmap = bitmap;
this.invalidate();
}
@Override
protected void onSizeChanged(int width, int height, int oldWidth, int oldHeight) {
int bitmapWidth = mBitmap != null ? mBitmap.getWidth() : 0;
int bitmapHeight = mBitmap != null ? mBitmap.getWidth() : 0;
if (bitmapWidth >= width && bitmapHeight >= height)
return;
if (bitmapWidth < width)
bitmapWidth = width;
if (bitmapHeight < height)
bitmapHeight = height;
Bitmap newBitmap = Bitmap.createBitmap(bitmapWidth, bitmapHeight, Bitmap.Config.ARGB_8888);
Canvas newCanvas = new Canvas();
newCanvas.setBitmap(newBitmap);
if (mBitmap != null)
newCanvas.drawBitmap(mBitmap, 0, 0, null);
mBitmap = newBitmap;
mCanvas = newCanvas;
}
private void createFakeMotionEvents() {
MotionEvent downEvent = MotionEvent.obtain(SystemClock.uptimeMillis(),SystemClock.uptimeMillis()+100, MotionEvent.ACTION_DOWN, 1f, 1f ,0);
MotionEvent upEvent = MotionEvent.obtain(SystemClock.uptimeMillis(),SystemClock.uptimeMillis()+100, MotionEvent.ACTION_UP, 1f, 1f ,0);
onTouchEvent(downEvent);
onTouchEvent(upEvent);
}
@Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(Color.BLACK);
canvas.drawBitmap(mBitmap, 0, 0, mPaint);
canvas.drawPath(mPath, mPaint);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
float x = event.getX();
float y = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
touchDown(x, y);
break;
case MotionEvent.ACTION_MOVE:
touchMove(x, y);
break;
case MotionEvent.ACTION_UP:
touchUp();
break;
}
invalidate();
return true;
}
/**----------------------------------------------------------
* Private methods
**---------------------------------------------------------*/
private void touchDown(float x, float y) {
mPath.reset();
mPath.moveTo(x, y);
curX = x;
curY = y;
}
private void touchMove(float x, float y) {
float dx = Math.abs(x - curX);
float dy = Math.abs(y - curY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
mPath.quadTo(curX, curY, (x + curX)/2, (y + curY)/2);
curX = x;
curY = y;
}
}
private void touchUp() {
mPath.lineTo(curX, curY);
if (mCanvas == null) {
mCanvas = new Canvas();
mCanvas.setBitmap(mBitmap);
}
mCanvas.drawPath(mPath, mPaint);
mPath.reset();
}
}
答案 1 :(得分：1)
我使用过这个库：com.github.gcacace：signature-pad：1.2.1 有了这个，我能够清除并保存签名。如果它也支持编辑，则不会尝试。