Android 位图上的撤消功能不起作用
我正在开发一个绘图应用程序,但面临一些撤消问题。当我在图像中绘制,然后按下“撤消”按钮时,它不会撤消我的上一个操作。我被卡住了。我用的是洪水填充算法。 看看下面代码中的撤销功能,我想我做得不错,但请检查一下,告诉我实际问题出在哪里Android 位图上的撤消功能不起作用,android,android-studio,Android,Android Studio,我正在开发一个绘图应用程序,但面临一些撤消问题。当我在图像中绘制,然后按下“撤消”按钮时,它不会撤消我的上一个操作。我被卡住了。我用的是洪水填充算法。 看看下面代码中的撤销功能,我想我做得不错,但请检查一下,告诉我实际问题出在哪里 public class MainActivity extends AppCompatActivity implements View.OnTouchListener { Button red, blue, yellow, undo; Paint paint;
public class MainActivity extends AppCompatActivity implements
View.OnTouchListener {
Button red, blue, yellow, undo;
Paint paint;
private RelativeLayout drawingLayout;
private MyView myView;
private ArrayList<Path> paths = new ArrayList<>();
private ArrayList<Path> undonePaths = new ArrayList<Path>();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myView = new MyView(this);
drawingLayout = (RelativeLayout) findViewById(R.id.relative_layout);
drawingLayout.addView(myView);
red = (Button) findViewById(R.id.btn_red);
blue = (Button) findViewById(R.id.btn_blue);
yellow = (Button) findViewById(R.id.btn_yellow);
undo = (Button) findViewById(R.id.undo);
red.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
paint.setColor(Color.RED);
}
});
yellow.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
paint.setColor(Color.YELLOW);
}
});
blue.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
paint.setColor(Color.BLUE);
}
});
undo.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
myView.onClickUndo();
}
});
}
@Override
public boolean onTouch(View v, MotionEvent event) {
return false;
}
public class MyView extends View {
final Point p1 = new Point();
Bitmap mBitmap;
ProgressDialog pd;
Canvas canvas;
private Path path;
public MyView(Context context) {
super(context);
paint = new Paint();
paint.setAntiAlias(true);
pd = new ProgressDialog(context);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeWidth(5f);
mBitmap = BitmapFactory.decodeResource(getResources(),
R.drawable.gp1_1).copy(Bitmap.Config.ARGB_8888, true);
this.path = new Path();
}
public void onClickUndo() {
if (paths.size()>0) {
undonePaths.add(paths.remove(paths.size()-1));
invalidate();
} else {
Toast.makeText(getContext(), getString(R.string.nomore), Toast.LENGTH_SHORT).show();
}
}
@Override
protected void onDraw(Canvas canvas) {
this.canvas = canvas;
paint.setColor(Color.GREEN);
canvas.drawBitmap(mBitmap, 0, 0, paint);
for (Path p : paths) {
canvas.drawPath(p, paint);
}
canvas.drawPath(path,paint);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
float x = event.getX();
float y = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
p1.x = (int) x;
p1.y = (int) y;
final int sourceColor = mBitmap.getPixel((int) x, (int) y);
final int targetColor = paint.getColor();
new TheTask(mBitmap, p1, sourceColor, targetColor).execute();
paths.add(path);
invalidate();
}
return true;
}
public void clear() {
path.reset();
invalidate();
}
public int getCurrentPaintColor() {
return paint.getColor();
}
class TheTask extends AsyncTask<Void, Integer, Void> {
Bitmap bmp;
Point pt;
int replacementColor, targetColor;
public TheTask(Bitmap bm, Point p, int sc, int tc) {
this.bmp = bm;
this.pt = p;
this.replacementColor = tc;
this.targetColor = sc;
pd.setMessage(getString(R.string.wait));
pd.show();
}
@Override
protected void onPreExecute() {
pd.show();
}
@Override
protected void onProgressUpdate(Integer... values) {
}
@Override
protected Void doInBackground(Void... params) {
FloodFill f = new FloodFill();
f.floodFill(bmp, pt, targetColor, replacementColor);
return null;
}
@Override
protected void onPostExecute(Void result) {
pd.dismiss();
invalidate();
}
}
}
public class FloodFill {
public void floodFill(Bitmap image, Point node, int targetColor,
int replacementColor) {
int width = image.getWidth();
int height = image.getHeight();
int target = targetColor;
int replacement = replacementColor;
if (target != replacement) {
Queue<Point> queue = new LinkedList<Point>();
do {
int x = node.x;
int y = node.y;
while (x > 0 && image.getPixel(x - 1, y) == target) {
x--;
}
boolean spanUp = false;
boolean spanDown = false;
while (x < width && image.getPixel(x, y) == target) {
image.setPixel(x, y, replacement);
if (!spanUp && y > 0
&& image.getPixel(x, y - 1) == target) {
queue.add(new Point(x, y - 1));
spanUp = true;
} else if (spanUp && y > 0
&& image.getPixel(x, y - 1) != target) {
spanUp = false;
}
if (!spanDown && y < height - 1
&& image.getPixel(x, y + 1) == target) {
queue.add(new Point(x, y + 1));
spanDown = true;
} else if (spanDown && y < height - 1
&& image.getPixel(x, y + 1) != target) {
spanDown = false;
}
x++;
}
} while ((node = queue.poll()) != null);
}
}
}
}
public类MainActivity扩展了AppCompatActivity实现
View.OnTouchListener{
按钮红、蓝、黄、撤消;
油漆;
私人相对性图纸布局;
私有MyView-MyView;
私有ArrayList路径=新ArrayList();
private ArrayList undonePaths=new ArrayList();
@凌驾
创建时的公共void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myView=新的myView(此);
drawingLayout=(RelativeLayout)findViewById(R.id.relative_布局);
drawingLayout.addView(myView);
红色=(按钮)findViewById(R.id.btn_红色);
蓝色=(按钮)findViewById(R.id.btn_蓝色);
黄色=(按钮)findViewById(R.id.btn_黄色);
undo=(按钮)findViewById(R.id.undo);
red.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图v){
油漆。设置颜色(颜色。红色);
}
});
黄色.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图v){
油漆。设置颜色(颜色。黄色);
}
});
blue.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图v){
油漆。设置颜色(颜色。蓝色);
}
});
undo.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图v){
onClickUndo();
}
});
}
@凌驾
公共布尔onTouch(视图v,运动事件){
返回false;
}
公共类MyView扩展了视图{
终点p1=新点();
位图mBitmap;
进展性帕金森病;
帆布;
专用路径;
公共MyView(上下文){
超级(上下文);
油漆=新油漆();
paint.setAntiAlias(真);
pd=新进度对话框(上下文);
绘制.设置样式(绘制.样式.笔划);
绘制.设置行程连接(绘制.连接.圆形);
油漆。设置行程宽度(5f);
mBitmap=BitmapFactory.decodeResource(getResources(),
复制(Bitmap.Config.ARGB_8888,true);
this.path=新路径();
}
公共void onClickUndo(){
if(path.size()>0){
undonePaths.add(path.remove(path.size()-1));
使无效();
}否则{
Toast.makeText(getContext()、getString(R.string.nomore)、Toast.LENGTH_SHORT.show();
}
}
@凌驾
受保护的void onDraw(画布){
this.canvas=画布;
油漆。设置颜色(颜色。绿色);
画布.drawBitmap(mBitmap,0,0,paint);
用于(路径p:路径){
画布.绘图路径(p,油漆);
}
画布.绘制路径(路径,绘制);
}
@凌驾
公共布尔onTouchEvent(运动事件){
float x=event.getX();
float y=event.getY();
开关(event.getAction()){
case MotionEvent.ACTION\u DOWN:
p1.x=(int)x;
p1.y=(int)y;
最终int sourceColor=mBitmap.getPixel((int)x,(int)y);
final int targetColor=paint.getColor();
新建任务(mBitmap、p1、sourceColor、targetColor).execute();
路径。添加(路径);
使无效();
}
返回true;
}
公共空间清除(){
path.reset();
使无效();
}
public int getCurrentPaintColor(){
返回paint.getColor();
}
类任务扩展异步任务{
位图bmp;
点pt;
int replacementColor,targetColor;
公共任务(位图bm、点p、点sc、点tc){
this.bmp=bm;
这个p.pt=p;
this.replacementColor=tc;
this.targetColor=sc;
setMessage(getString(R.string.wait));
pd.show();
}
@凌驾
受保护的void onPreExecute(){
pd.show();
}
@凌驾
受保护的void onProgressUpdate(整型…值){
}
@凌驾
受保护的Void doInBackground(Void…参数){
溢流填料f=新溢流填料();
f、 泛光填充(bmp、pt、targetColor、replacementColor);
返回null;
}
@凌驾
受保护的void onPostExecute(void结果){
pd.解散();
使无效();
}
}
}
公共级填洪{
公共空白泛光填充(位图图像、点节点、int targetColor、,
int replacementColor){
int width=image.getWidth();
int height=image.getHeight();
int target=targetColor;
int replacement=replacementColor;
如果(目标!=更换){
Queue Queue=new LinkedList();
做{
int x=node.x;
int y=node.y;
而(x>0&&image.getPixel(x-1,y)=目标){
x--;
}
布尔spanUp=false;
布尔值=假;
而(x0
&&image.getPixel(x,y-1)=目标){
添加(新点(x,y-1));
spanUp=true;
}如果(spanUp&&y>0),则为else
&&image.getPixel(x,y-1)!=目标){
spanUp=false;
}
如果(!spanDown&&y<高度-1